# Ford 850 Project



## ErnieChilton (Jul 25, 2014)

I have been posting to the Repair & Technical Forum, but "HarveyW" suggested that I could probably get more help from the Ford/New Holland Forum. My nephew gave me his dad's old Ford 850 SN 21021 with a 5-speed xmission, !0"- 15 Spline clutch. He thought it had been running when it was parked outside about 10 years ago. To bring you up to this point:

1. Engine Frozen. Tried pouring ATF, PBlaster, Kerosene, Marvel Mystery Oil, etc in cylinders. After 6 months nothing. Removed head, found 1 pushrod loose and 2 valve/seats badly rusted. Installed new valves, springs & reground seats. Pounded on stuck cylinder (#2) with wood block and BFH. It did not budge.

2. Removed rod caps and dropped crank. #4 rod journal had spun, could not be cleaned up to .040 under so found used crank on eBay that cleaned up to .010 on rod and mains. Oil looked like it hadn't been changes since 1955!

3. Forced #2 piston out with hydraulic jack. Decided to install new sleeves/pistons. Old sleeves can out kicking & screaming. New sleeves went in same way. Checked clearances and found sleeves had distorted slightly. Had sleeves honed to give proper clearance.

4. Reassembled and, after locating a 15 spline clutch alignment tool am ready to bolt to tractor.

While waiting for some warmer weather have been thinking about the installation. In the past, I would sling an engine in and get it aligned with the xmission shaft, then rock the car back & forth to get the splines to engage. However, with the front of the tractor being supported by an engine stand, I cannot rock it enough to get the xmission shaft splines to rotate.

Does anyone have any tips on aligning the splines?

Also, while waiting for warmer weather have tackled the cast iron carb, a TSX593. It was badly rusted so I soaked it for several months in "Evaporust". Did a decent job in removing rust but cannot get the brass fuel float valve seat, idle jet and the 8-32 brass plug from the bottom of the carb out. Would like to remove them to make sure that the passages are clean. A 1/2" carb screwdriver would probably work on the float seat, but largest I can find is 7/16" from Snapon. Could probably get it out with a small pipe wrench, but the float pedestal is in the way and it is installed with rivets. The other 2 are so small and in so tight I feel certain that I will just bugger them up.

Any suggestions on how to get them out?


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## harry16 (Dec 8, 2011)

Hello Ernie,

To align the splines, put the transmission in neutral, engage the PTO lever, and turn the PTO shaft. I use a small pipe wrench on the PTO shaft. 

When I can't get a jet out, rather than bugger it up (which I'm very good at BTW!!), I usually run a wire through it and blow it out with compressed air and let it be. 

Maybe someone else here can come up with something.


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## EdF (Sep 15, 2014)

Ernie,

My luck with extractors is virtually nil. They break and then you have to get the tip of the extractor out of the hole. 

If you feel you must get a stuck jet out, you will probably have to drill it out. Use a left handed drill bit (you might get lucky and back it out with the drill bit). Work your way up in bit size, and leave the old threads in place. Then run a tap thru the old threads to clean them out. 

It all depends how centered and straight you are when drilling the jet out. If you are not reasonably centered/straight with the drill, you may bugger the threads in the passage, and ruin carburetor.


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## ErnieChilton (Jul 25, 2014)

*Bend to Fit, Paint to Match, Use As Is*

I have completed work on the engine, rebuilt or replaced everything but the starter. Now I am ready to see if this sucker runs. I'm worried about the carb since I could not get the float valve seat and idle jet out but tried to clean the passages with carb cleaner and compressed air. Should at least work good enough to get it started. I now have to paint and mount the front axle. Don't want to start the engine with the it cantilevered off the transmission with no support.

When I disassembled the tractor there was a lot of PBlaster, descriptive terminology and busted knuckles, so I don't remember exactly how some of the parts came off. In particular, the heat shield between the tank and engine is confusing. On page 107 of the shop manual and page 6-20 of the parts catalog it is shown above the muffler, but the attachment bracket on the tank bottom puts the shield on the other side of the engine. Seems sort of stupid to not put it between the muffler and fuel tank but that's where it fits. Also the fuel line was routed between the intake and exhaust sections of the manifold. Guess that might be OK since a gravity feed system shouldn't vapor lock. But hot fuel is never good.

Also the yahoo that worked on this tractor replaced the muffler with an aftermarket one and had pounded the bottom flat so it would fit over the manifold. Then proceeded to weld an extension over the end of the muffler elbow to get the muffler inlet to fit. Then pounded the front fender in so he (or she) could bend the flex exhaust pipe past it. That one is going to be fun to fix. Can anyone give me the dimensions of the original muffler?

Next project is to clean the rust out of the fuel tank. Any suggestions?


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## Dad2FourWI (Mar 25, 2015)

WOW.....

I really cannot offer much (sorry) -

but I wanted you to know that I am very impressed by your progress!!!!

That is quite a project!!! - You make me feel like a newbie working on an old hay rake!! 

Keep up the great work and send some pics! - everybody loves pics!!!!!!

Cheers!
-Dad2FourWI


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## sixbales (May 18, 2011)

Howdy Ernie,

Try an internet search for restoring a fuel tank - youtube. There are a number of methods to clean out a tank. Your choice.
_________________________________________________

See attached parts diagram. You can get an aftermarket muffler from Messick's for $25. Your engine should be the 172 CID. Note that the diagram shows a heat shield above the muffler. A bit expensive.....You can probably make one??


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## ErnieChilton (Jul 25, 2014)

*850 Heat Shield and Paint Scheme*

Think I have found the solution to the muffler-fuel tank heat shield in my previous post. The fuel tank is 2" narrower at one end. Being an old racer, I naturally assumed that was the front since you always mount pointy things facing the front to reduce drag. I guess the Ford tractor engineers weren't racing fans. If I mount the wider end toward the front, the heat shield is above the muffler. The front and rear tank brackets are identical so they can be mounted at either end of the engine, this puts the spring attachment at the front of the tractor. Carefully studying the photos in the shop manual seem to verify this. All the parts are shown in the Parts Catalog but the illustration does not specify which end is the front. Can anyone verify this for me. I would hate to get the tank all plumbed in only to find the engine cowling doesn't fit.

Also the sprint (PN B-8130) used to mount the tank at the wide end had disintegrated. I am trying to find a suitable replacement but having trouble finding one with the correct spring rate. It must be fairly stiff to support a full tank of fuel, but not as stiff as a valve spring. Anyone have any suggestions?

Attached are jpegs of the engine. Except for the tank and radiator I am pretty much finished with the front half. If the engine runs, then I will start on the back half. You will notice that the instrument panel is painted vermillion. After painting it, I discovered that the correct paint scheme should have it grey. Found several photo's where the instrument panel and tank cover are vermillion and am considering using that scheme rather than repainting the instrument panel. The original owner had painted the entire tractor with a million cans of black spray paint so I do not have any indication what the original color was.


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## sixbales (May 18, 2011)

Looks good Ernie!! Post more photos.

If you need parts, try http://tractorhouse.com. They have 36ea. Ford 800's listed in salvage, plus 5ea. 850's and 3ea. 860's.


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## ErnieChilton (Jul 25, 2014)

*&%(@# Ford 850 Fuel Tank*

After resolving the heat shield problem, I test mounted the tank to try a spring I found and instead of solving the problem just added confusion to it. With the spring 1/2 compressed the tank slopes to the rear 5 degrees. If I remove the spring from the front mount, the tank slopes to the back by 2 degrees. I'm assuming it should be level. The seam between the 2 tank halves reads level, but the tank halves are not symmetrical, so the top and bottom of the tank still slopes. My 0 degree reference is the engine. The fuel outlet is in the center of the tank so a 5 degree slope leaves about 3/4" of fuel that cannot be picked up when the tractor is level. One caveat is the tank bracket which does not look like the one in the parts catalog. I guess that the old one rusted away and someone fabricated a new one from 1/4" strap. My inclination is to leave the spring off and hard mount the front like the rear mounting.

Have been giving thought to cleaning the inside of the tank. The tank seems pretty solid so I do not have to worry about pin holes. All the You Tube videos show them removing the fuel level sensor which gives them a big hole to empty the tank. The only access holes in the 850 tank are the filler which protrude about an inch into the tank so you cannot drain the loose crud out of it. The other is the 5/8" outlet which is pretty small. This one is going to test my patience.


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## ErnieChilton (Jul 25, 2014)

*It Runs!*

I have not worked this project for almost 9 months. It was too hot in the barn (metal building) and fall was full of racing and football. A kerosene heater works fine in the barn for winter so I have stated back on the Ford 850 project. Also, sold the winged sprint race car at the beginning of the year so now have funds to pound down another rat hole.

Rigged up a temporary gas tank using a Folgers coffee container and cranked it. Started right up and I let it run for a few seconds (no radiator yet). Found a leak around the governor control arm so had to replace the seal. Cranked again and let it run little longer. Blew oil 6 ft across the barn from around filter adapter plate. Since I had not replaced the old gasket when the engine was reassembled, I made a new gasket and started again. Still blew oil. Thinking the adapter plate might not have been seating good, bought a new adapter kit and installed. Still blew oil. I am a little slow but I do learn from experience. Wrapped a towel around the filter and this time installed an oil pressure gauge. Started again. When the gauge pegged at 100 psi I knew I had found the problem. Dropped the pan and removed the oil pump. I found out that when I reassembled the oil pump I had put the relief plunger in backwards! Put it in correctly, reassembled everything and started it again and let run for about 5 seconds. NO OIL Leak. Then installed the radiator which was in pretty rough shape but did not leak when I filled it. Started and ran for about 5 minutes. Engine ran great, no oil leaks, no water leaks.

BUT had a leak from the xmission case. I had filled the xmission with diesel intending to run it for a sort while to clean everything. Diesel was dripping from the xmission case. Not Good. Split the tractor again and replaced the xmission shaft seal. Finally got it back together and no leak.

I am now working my way back on the tractor and have now reached the hydraulic stuff. Started looking at the draft control and tried to remove the draft control rocker PN NCA535B. The pins to the rear end housing and the draft control rod are frozen in. Really, really frozen. Could not pound them out. Tried heating with a propane torch using a MAP cylinder but cannot get either to budge. I can buy a new rocker arm but am leery of pounding too hard on the pin going thru the case ear. Certainly don't wand to break that off.

Any suggestions on how I can get that pin out? I tried to turn it my inserting a steel rod into the lynch-pin hole, but that just broke the end of the pin off? Did I mention that it is really stuck?


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## sixbales (May 18, 2011)

Can you drill the pin out? Start with a small bit and work your way up. Go gently so you don't break the bit off.


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## ErnieChilton (Jul 25, 2014)

Drilling it out is an option I have considered, however I have not had any luck drilling out hard steel pins. I have a sheared Grade 3 3/4" bolt on my other tractor that I have been drilling on for over a year. I drill for about 30 min then give up. About once a month I will walk by, and give it another try. So far I have a small hole about 1/4" deep, but not enough for to extractor to grab. Don't know how hard this pin is but it certainly is not soft steel. Also the side clearance between the pin and the case is pretty close making it difficult to put pressure on the drill. This is my last option but if I do try drilling, I would cut the pin off at both ends by inserting a hack saw blade between the rocker and the case ear. This would reduce the amount of drilling down to about 1". However, if I do this, I am screwed if I cannot get it out because I have no way to mount the rocker.

My preferred option at the moment is to ignore it and leave the pins in. They certainly won't back out on their own. However this assumes the hydraulics are working, which leads to my next problem.

How do you prime the pump? Procedure from the manual seems to assume that some fluid is in the system. When the engine is split from the transmission all of the fluid drains from the system. The only way to get the pump to prime seems to be to remove the pump from the engine, fill the manifold tubes and reattach the pump. It seems that anytime you split the engine you would have this problem. Am I missing something in my assumptions?


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## sixbales (May 18, 2011)

Ernie,

I assume that you have a piston pump. See attached diagram. Pull plug #17 and fill the pump with fluid. Reinstall plug. Pull plug #3. Fill pump here and install plug loosely. Start engine and tighten plug when fluid starts coming out thru the threads of the loose plug. 

If you continue to have problems, install a hose barb in port #3 and run 1/2" clear plastic tubing back to the reservoir filler port. The advantage of this approach is you can see fluid and air bubbles in the fluid thru the clear tubing.

If your pump doesn't look like the attached, let me know.


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## ErnieChilton (Jul 25, 2014)

*850 Piston Pump*

Sixbales,

Close but not quite. My 850 pump is a ball bearing piston pump that is different from the roller bearing pump. It has a output port plug but does not have an input port plug. I don't think filling the output port alone will prime the pump.

My next step will be to install the hose barb/tubing into the output port and then run the engine for several minutes to see if it will self-prime. It might be that the pump is not generating enough lift to prime it by only cranking it for a short time. If that works, I will install a pressure gauge in the output port to make sure the pump output is sufficient.


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## sixbales (May 18, 2011)

Ernie,

If it doesn't prime for you, put a small amount of air pressure (10-15 psi) on the reservoir.

Afterthought...Is your transmission level full? The hydraulic pressure and suction tubes run through the bottom of the transmission. They can corrode and develop leaks. If it sucks the transmission dry, it can get air from there.


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## ErnieChilton (Jul 25, 2014)

*Pump Primed but Carb Problems*

It primed! Finally got the hyd pump primed using the pressurized reservoir method. Worked fine once I discovered you have to make sure all the thru bolt holes are plugged. I got a little scared about the "corroded suction tube" comment. The last thing I wanted to do was split the tractor again, although I am getting pretty good at it. However, the lift arms seem to lift slower than I was expecting with no load. Might be that I am judging it against my other tractor, a 575 Mahindra. Will put a pressure gauge on it once I get my carb issue (see below) resolved.

The engine runs fine at about 1200 RPM and above. However when try to adjust the RPM below that it begins to "hunt", i.e. engine slows, governor opens throttle, picks back up, slows again, etc. Idle adjustment screw has no effect, can close it completely or back it all the way out, no change. When I rebuilt the carb, I could not get the float seat, idle jet or the small plug in the bottom out, so tried to clean out the best I could and hope for the best. Float seat works fine, but looks like the idle passage is plugged.

Since I have zero confidence that I an get the idle jet out, I am anticipating the purchase of a new carb. The one on the tractor is a TSX593. Looking on the internet I can fine a new 706 carb at a reasonable price. The description says it is a direct replacement for a 593. But I have had problems with "direct replacement" parts before. Can anyone verify that a 706 is a bolt on replacement with no modifications to linkage, etc ?


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## HarveyW (Sep 15, 2014)

Hello Ernie,

Listed below is a Zenith carburetor available from Yesterday's Tractor: ______________________________________________________ 

Carburetor, New - With reversible linkage. This Zenith carburetor outperforms the original carbs used on: 800 series, 900 series tractors 1955-1957 with 172ci gas engine. This Zenith carb replaces Marvel-Schebler TSX706 (supersedes TSX593) and Ford EAF9510G. Center to center on the 2 mounting bolts is 2 3\8 inches. Made in USA, 1 year warranty. (Part No: 13877)
______________________________________________________

Two things I see with this ad: 1) Reversible linkage, and 2) Mounting bolt spacing. 

Reversing the linkage is no big deal, but you are out of luck if the mounting bolt spacing isn't right.

According to the YT ad, the 706 supersedes the 593.


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## ErnieChilton (Jul 25, 2014)

*$&!# Carburetor*

THE TRACTOR GODS DO NOT LIKE ME. Here is where I am with my 850 carburetor. Found a new in-the-box Zenith 706 (#13877) at All States Ag Products for under $200 with shipping. It bolted directly in except it does not have a Hi Speed Adjustment because the sediment bowl obstructs the place for the adjusting screw so they use a fixed jet and plug. Seemed a reasonable modification.

So I installed it and engine would start, but "blubbered" like it was running rich. Checked carb float and it appeared OK. After a few choice but unprintable comments about the new carb, bolted the old one back on and cranked the engine. Remember this one ran fine but would not idle below 1200 rpm. Now it "blubbers" like the Zenith!!!! Completely closed the Hi Speed and Idle adjustments. Still "blubbers". Checked the plugs and they confirmed the engine was running rich. Rechecked the timing and point gap was .020 and set at 4 deg BTC. Placed finger over each plug hole and cranked the engine over. Had compression on all cylinders with a slight suction as the piston starts down. Will get a compression checker and do a good check, but am at a complete loss. Both carbs appear to be running rich but there must be something else causing it.

I would bang my head against the wall but the barn is a steel building and that hurts.


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## sixbales (May 18, 2011)

Ernie,

The point setting spec for your tractor is .024"-.026". Most guys set the points at 
.025". Timing at 475 rpm 5 degrees BTDC. At 2000 rpm timing 26-28 degrees BTDC. To check just about anything on your 850, go to John Smith's Old Ford tractors on the internet. 

I would return that carburetor if possible. If not, call Zenith and confirm the correct fixed jet size for the main jet. Also, the float setting.


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## sixbales (May 18, 2011)

Make sure the choke is opening all the way, or possibly obstruction in the air intake.


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## ErnieChilton (Jul 25, 2014)

*2 Bad Carbs?*

My dilemma is that I have 2 carbs with the exact same problem, the new Zenith 706 and Original TSX593 (which operated fine above 1200 rpm but now runs rich). The choke is open and nothing is attached to the carb intake when using either carb.

On the TSX the float is shutting off when the carb is inverted. I haven't checked the float to the 026 - 029 spec but was not too concerned initially since it seemed to run OK at 1200. I will set the float level as the next step but am just grasping at straws at the is point.

I do not have any specs on the Zenith but will try to find them on the web. However, the initial float check confirmed that the float does shut the fuel off.

I statically timed the engine at 4 deg BTC as a starting point, initially the engine ran fine just would not idle.. I could not time it with a light because it would not idle, now it just doesn't run long enough. I will reset the points to spec but wasn't too concerned since I was getting a good spark.

I hesitate to return the Zenith since I am pretty sure the TSX has rust in the idle circuit that I cannot clear out, so I will need a replacement eventually.

At least it is getting warmer here so the barn offers a little more comfortable place to work.


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## ErnieChilton (Jul 25, 2014)

*Putting Lipstick On A Pig*

Well, after fighting my engine problem for 1-1/2 years, the engine on my Ford 850 tractor is running good. I am now in the process of “putting lipstick on a pig”. Spent several months sand blasting and putting body lead and bondo on the fenders, and hood components.

This tractor was a real rust bucket when I got it and was covered with dust, rust and dents. I did not pay too much attention when disassembling it but now that I have tried a dry fit before the final paint, things are not going so good. I was surprised at the gap between the side panels and the top tank door. The front of the tank door is only 9-3/4 wide and the Front Emblem Housing is 10-1/2” wide, leaving a gap of 3/8” on each side of the door. The gap is about the same at the rear of the door where the side panels bolt to the side of the Rear Panel Ass’y, making a pretty sloppy fit. Since the side panels bolt directly to Rear Panel and Emblem Housing, there is no way to take up any of the gap. Is this the normal fit? If it is, I spent a lot of time trying to get these components to look good only to end up with an ugly gap the door sides. 

Haven’t mated the door to the funny looking hinge pieces yet but that looks as if it is going to be another exercise in frustration and patience.

Another problem occurred when I tried to mount the side panels. The spring for the front mount of the tank was broken in several pieces when I disassembled it. I replaced it with one I had in my spring box since I could not find a source for a new one. Unfortunately it made the tank too high and there was not enough clearance between the tank and the side panels, even when I tightened the mount screw to the point of coil bind. I found that I had to mount the front of the tank directly to the engine mount bracket with a ¼” rubber spacer before I had enough clearance to mount the side panels. Even now I am sweating out the clearance for the gas cap to fuel door.

Another item has me confused. The side panels have tabs welded to them for mounting the grill. These tabs have hex holes .825” across the flats for the grill retaining screws. What goes in these holes? The Parts catalog does not show anything.

Any suggestions or enlightenment anyone could supply would be greatly appreciated.


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## Joe850 (Feb 19, 2017)

My 850 isn't in the best shape cosmetically, but got her running good now at least. I only have one of the retaining nuts for the upper grill. Here is a picture of the one I have.


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## sixbales (May 18, 2011)

Howdy Ernie,

One possibility is that your sheet metal may be cobbled together from different era tractors. I have a Ford 3600 that the sheet metal is comprised of parts from several different tractors. I call it the "super mutt'. Who knows what happened to some of these old tractors? Mine was used as a logging tractor, and I can envision a tree falling on it? 

The spring you used may be the wrong one. See item #29 on attached diagram. Messicks may be able to help with this spring. Another possibility is that the tank has been changed out and the spring is not required. I'll send you another fuel tank diagram where there is no spring. 

Also attached is a sheet metal diagram for an 850.


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## sixbales (May 18, 2011)

Ernie,

See attached parts diagram with no spring on fuel tank.


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## ErnieChilton (Jul 25, 2014)

Joe 850 – Thanx for the photo. It gives me something to reference. I think I will just tack weld a steel piece across the hex opening and then drill/tap a hole in it for the grill retaining screw. Seems like a simpler solution than trying to locate the part.

sixbales – Have not seen the parts diagram for the gas tank no spring version, but the spring version is in the Ford Parts manual, however the Messicks version does give me a part number to search on. 

The sheet metal drawing is the same one as I have from the Ford Parts Catalog, but the side panels on my 850 do not look like the drawing. Instead, they are one piece and the lower mounting hole is not a separate piece. The Dennis Carpenter catalog shows a picture of the NAA-16612-B 1955-1957 600 800 Ford Script Hood on the back cover which looks like mine except for the Nose Piece (PN NCA-16613-A). My 850 has a solid piece for the emblem mount, like the PN 311319 shown on page 106. They both look exactly the same except for the emblem mounting.

I have considered the “cobbled together” scenario if the nose piece is wider than the one I have, but even if it is, I would still have a ¾” difference where the panels bolt to the instrument housing, which would make the gap correct at the front but wider at the back. I have actually replaced the right side with one from a Ford 2000 because the original one was badly rusted and dented, and since this is to be a work tractor it does not need to be anatomically correct. Someone had tried to make repairs with a welding torch and it was unusable. I measured both carefully and there is no discernable difference except the 2000 piece is non-script. I decided to just paint a red script logo on that one and paint the script on the other side to match. I even tried using the original piece when dry fitting, but it gave me the same gap. I think I am stuck with the wider but even gap. Looks like it is going to take a lot more “lipstick” than I counted on.


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## ErnieChilton (Jul 25, 2014)

I have decided that the sloppy fit between the gas tank door and the front hood pieces is a problem to be dealt with using my old “bend to fit, paint to match, use as is” philosophy. The sheet metal components are what I have and to get new ones is $$$ out of my reach, so what I got is what I use.

However, before I paint and mount the front hood pieces I decided to clean up my gas line hookup. The original Fuel Shutoff valve was frozen in the open position and when I tried to close it with a pipe wrench, surprise, it sheared off the knob. I had been running with an in-line shutoff and fuel filter since then. But, because access to the fuel tank requires the complete removal of the hood components I decide to replace the broken valve with a new one. Ordered one from YT (Yesterday’s Tractors) and they promptly send a new one that came in a Sparco box but made in Tiawan. However, the aluminum casting was of low quality and when I tried to connect the fuel line, I stripped out the soft aluminum threads. ARGG! So I ordered another one from YT. This one was from a different manufacturer and made in India. The casting was much harder and I managed to make the connection without stripping it. Everything is finally looking up to this point. After mounting the gas tank and routing the metal fuel lines, I thought I was through. Poured in some fuel and went about my job of prepping the sheet metal for paint.

Came back about an hour later and fuel was dripping out of the carb. As reported in an earlier post, I had a leaking float valve problem which I had decided to temporarily ignore. Investigation revealed that the new shutoff valve would not completely shut off the fuel. No matter how hard I tried to tighten the shutoff knob, it would leak, dripping about one drop every few seconds. Now I have the problem of not being able to shut off the fuel to a leaking carb. After replacing the float needle and seat with new ones, lowering the float level and replacing the needle and seat with a second new set, it still leaks. I can turn the carb upside down so that the float is at its shut off position and blow into the fuel inlet and it does not let air through. Remount the carb and it leaks fuel! 

I am back to using an external inline shut off valve, but am at a loss on how to fix the leaking carb. I hesitate to purchase a new valve needle and seat because I have tried putting 2 new sets in with no luck. Any suggestions, no matter how wild, would be appreciated.


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## ErnieChilton (Jul 25, 2014)

After replacing the float needle and seat in the TSX593 carb 3 times and bending the float arms to lower the bowl level, I finally decided to prove if it was the float valve problem or not by plugging up the seat hole with epoxy and remounting the carb. Lo and behold, the carb still leaks!!! The bowl will still fill with fuel and run out of the air intake. I am now completely at a loss. What can cause the fuel to leak into the bowl even if the fuel valve is sealed off? This is a new one on me, I have never had fuel get into a carb with the valve completely sealed off. I know there are a lot of little holes drilled in the carb body, but don’t know if it is possible for fuel to get past them into the carb. Something isn’t right with this carb.

I have a Zenith replacement carb that I bought when I originally thought I had a carb problem (was a bad ignition coil) but didn’t use it. I had much rather use the TSX because it looks like a carb from a tractor, the Zenith looks like it came off a lawnmower. However I might be forced to use it if I cannot get the TSX to stop leaking. PLEASE, PLEASE if anyone has any suggestions, let me know. I will try anything at this point.

I have 1 question that is not related to the carb. What color is the grill on an 850 tractor. Mine came painted red with the rest of the tractor black, so I have no confidence in the red color. I have seem pictures of similar tractors with the grill painted gray. What is the correct original color?


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## TraderMark (Nov 15, 2011)

Ernie,
If you have the hole for the needle and seat filled with epoxy and sealed completely, can you take the bowl, the float and everything else off and leave the upper half of the carb mounted so you can try and actually see where the gas is coming in??

Just a thought.

Mark


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## ErnieChilton (Jul 25, 2014)

*Carb Leak Fixed!*

I took TraderMark's suggestion and mounted the carb with the plugged up seat minus the bowl. After about 3 minutes I could see fuel coming out from around the float valve seat. The valve needle was not leaking, but fuel was getting past the screw-in seat.

The seat was in as tight as I could get it and a new gasket was put in, but it still leaked. This carb was really rusted inside when I got the tractor and it took lots of rust remover and scraping to get it clean. Looking closely at the seat surface on the carb revealed tiny rust pits on the seat which prevented the gasket from making a good seal. I put some thread sealing tape on the valve seat threads and dabbed a bit Permatex #2 on the carb seat surface, reassembled and turned the fuel on. Left it overnight and this morning it had not leaked. Problem solved.

All the while I was thinking why didn't I think of mounting it without the float bowl. Seems like an obvious thing to do, but not for "Ole Ern". I tend to over analyze problems and many times fail to see the obvious, like the 1-1/2 years I spent tracking the engine running problem to a coil that failed when the duty cycle increased.

Now if anyone can tell me what color to paint the 850 grill I will be set for a while.


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## TraderMark (Nov 15, 2011)

Glad to hear you got that carb leaked fixed, Ernie. :bouncy:


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## ErnieChilton (Jul 25, 2014)

*850 Hydraulics*

I have been rebuilding a Ford 850 tractor over the past 2 years and now have turned my attention to the hydraulics while I wait for suitable weather to finish painting the sheet metal.

I do not know what level of performance to expect from the hydraulic system. Initially I had trouble getting the system primed (a ball bearing piston type) but got that resolved by putting a few pounds of pressure on the hydraulic chamber and cranking until fluid came out of the pipe plug port an the end of the pump. I first assumed this port was the output but after placing a gauge on it and getting no reading realized it was connected to the input side of the pump, my pump does not have a plug on the output side even though the repair manual shows one. It takes approx 13 sec for the lift arms to completely raise. It doesn’t seem to make any difference with the load, couldn’t discern any difference between no load and 500#. When it engine is shut down, the lift arms will slowly leak down in about 2 hours. If left sitting overnight, the pump loses prime but will reprime fairly easily by removing the pipe plug and cranking it over a few times.

Is the slowness of the response to raise the lift arms typical or do I have to look for what is causing it? Checking the output pressure is rather involved according to the manual, requiring the removal lift cover and installing an accessory plate.

The loss of prime overnight is my biggest concern. The manual suggests disassembly and examination of the pump and replacing o-rings which is a little work but reasonable. If that doesn’t work then they say to split the tractor and inspecting the suction tube for corrosion and replacing the o-rings. Something I really, really don’t want to do. I would think that the suction tube, which is located in the bottom of the transmission and is immersed in oil, should not suck air but transmission oil instead and would still retain prime.

Next I will check the pump pressure and replace the manifold o-rings to see if that helps and live with the leak down for now until I get enough courage to go into the lift cover. Splitting the tractor to check the suction tube is a non-starter. I might have to reprime the pump each morning before I use the tractor, but that beats splitting the tractor!


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