# Bolens Husky 1556 question



## Country Boy

I have a Bolens Husky 1556 tractor that just came into the shop I work at and I had a quick question regarding it. The tractor runs great, its just that you can't start it. You have to either use ether or propane gas to get it to start, but once it starts, it runs perfectly fine. The carb is clean, and you can see gas pooling in the throat of the carb when you crank it with the choke closed. Were there any known issues with these tractors? Any ideas? I haven't had a chance to look at it yet, but the owner had been talking to me over a few days about what he was doing to try and get it going. Sounds like he tried just about everything.

It really looks to be a nice solid tractor. I really wish companies made tractors like those old ones again. That was back when they were built to last.


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## jhngardner367

Rich,check for a leak between the carb,and the engine. Start it ,and run it at a little above idle,and squirt some carb cleaner at the mounts for the carb,and the manifold.Any change will indicate a leak.
Also run a compression test.


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## Country Boy

I should be working on this tomorrow. I'll check the gasket, but from the looks of things it is new or recently replaced. I also wanted to check the fuel pump to be sure its filling the bowl far enough to make it start. I know one of the fittings on the pump had been leaking and he sealed it back up. Not sure how good of a job he did. Leakdown test is a standard procedure now for me. I ran into problems last summer with an engine that seemed 100% like a carb or ignition issue, only to be a bad head. Now I do them on just about anything that doesn't run correctly. Only takes a minute and really tells you the state of the engine.


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## wjjones

What engine does it have CB?


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## Country Boy

Its got a Tecumseh HH150 overhead valve engine. I gave it a squirt of starting fluid and cranked it over and it backfired out the muffler and carb. Did a leakdown test on it and found that it was leaking badly from both valves. Tomorrow I have to pull the head and see about sealing the valves. I'm hoping lapping them or perhaps grinding and then lapping will take care of it because the valves are obsolete. Even if they were available, they are over $60 a piece. I found very little leakage past the rings so I am thinking the cylinder is okay. I should find out more tomorrow.


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## jhngardner367

*Hh150*

Rich, that engine has adjustable valves. Remove the valve cover,and adjust the exhaust valve to .005/.007, and the intake to .004/.006 . That should take care of it.
Once it is started,warm it up for 5 mins,then with a spray bottle set on "mist",spray it into the carb intake,with the engine at mid throttle.
This will clean any carbon from the valves/seats.


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## Country Boy

The rocker arms were loose when I did the leakdown test, and aren't applying any pressure to the valves. The unit is from 1973, and from the looks of it, the head has never been off. I'm thinking the valves have worn and the seats are probably worn as well. I can check the clearances on the valves, but I don't think that will help. I tried starting the unit, but all it would do is backfire out the carb and muffler. For some odd reason, I have a head gasket for it at work in the parts bin. Last one was sold in 1989, so this one has been on the shelf for a very long time. We have tons of old parts just sitting there for Tecumseh, Briggs, Ariens, and Kohler. Seems that the guy I replaced and the guy before him loved to have a huge stock of parts. I have 22 oil seals for a Briggs engine. The last one was sold in 1992. I had a guy buy one recently and his engine was built in 1963. Somehow I don't think I will be able to sell the rest in my lifetime! :lmao:


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## jhngardner367

OK. Then I would pull the head,as well. It may have crud on the valves/seats, weak valve springs,or(I hope NOT),burned valves.
When I did the one in my cousin's Sears ST 16, I had to replace the valves,and the guides,because of this.
Keep us posted,Rich,and post some pics!!


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## Country Boy

I've got some pics on my phone. I just have to upload them. I had to stop working on this for a bit as I got flooded with chainsaws all of a sudden. My big air lift table was covered from end to end with saws this morning! 

I got most of the shrouds off, but the one that covers the rear of the engine and the pulleys has been a real pain. Its still held on somewhere, but I can't tell where. I'm thinking I have to reach underneath the shroud and pull out the bolts that hold on the belt guide. I'm hoping they also hold on the cover too. This tractor looks like it was well taken care of. The paint is in excellent condition and most of the decals are still legible.


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## wilberj

Country Boy said:


> The rocker arms were loose when I did the leakdown test, and aren't applying any pressure to the valves. The unit is from 1973, and from the looks of it, the head has never been off. I'm thinking the valves have worn and the seats are probably worn as well. I can check the clearances on the valves, but I don't think that will help. I tried starting the unit, but all it would do is backfire out the carb and muffler. For some odd reason, I have a head gasket for it at work in the parts bin. Last one was sold in 1989, so this one has been on the shelf for a very long time. We have tons of old parts just sitting there for Tecumseh, Briggs, Ariens, and Kohler. Seems that the guy I replaced and the guy before him loved to have a huge stock of parts. I have 22 oil seals for a Briggs engine. The last one was sold in 1992. I had a guy buy one recently and his engine was built in 1963. Somehow I don't think I will be able to sell the rest in my lifetime! :lmao:


The 1556 was only made in 1972.


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## jhngardner367

The tractor might be a '72,but the engine could be later,as a replacement.


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## Country Boy

Its probably a '72 then. The guy I am fixing it for thought it was a '73 model but he wasn't sure. Well, I got it pulled apart yesterday, and found the problem. The exhaust seat had fallen out and was rattling on the valve, the exhaust valve guide had come loose and severely worn through the head and the intake valve guide was loose, though not as badly worn. You can tip the exhaust guide about 25° in its hole in the head. I have to bring the head to a machine shop tomorrow and see if they can bore it out, press in a bushing and then press in the new valve guides. I happened to have a set on the shelf that I had ordered for someone else who didn't pick them up. I think I can fix this head and re-use it, but a new head is still available. Its $260, but still available... 

Hopefully this will solve the issue. Taking that engine head off was a royal pain in the arse. You have to take the valve springs off before you can take the valve chest off so you can get the last head bolts out to get the head off. I couldn't get the exhaust pipe loose, so I had to reach between the valve spring coils with a needle nose vice grip to hold it still so I could get the keepers out. I have the tool for taking the springs off, but the manual says to reach in through the intake and exhaust ports to hold the valves steady.


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## jhngardner367

Yeah,I had the same problem with the one in the Sears,that my uncle had! 
I made a fixture for the top of the cylinder block,that bolts down,and puts pressure on the valves. It makes it a lot easier to remove/install the keepers !


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## Country Boy

Well, I got it back together and got it running. A local machine shop reamed out the holes for the valve guides and made up some bushings to fill the gap. I pressed it all back together and ground and lapped the seats and valves. The exhaust seat I was able to get seated again and I staked it in place with a center punch. Seems like it will hold. The engine didn't want to start at first, but I found that the customer had installed the gasket for the air cleaner housing upside down and it was blocking the carburetor vent. That wouldn't let the bowl fill with fuel. I had removed the air cleaner housing when I worked on it, but the gasket stayed stuck on the carb, so I left it. It runs great now, but it does burn oil. From what I found online, these engines were known to overheat and loosen the valve guides, which is exactly what happened here. Customer seemed happy with the repair, and I told him to keep an eye on the engine so it doesn't overheat.


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## jhngardner367

Rich, did you put any type of oil seal on the valves? Without one,they will burn a bit of oil. I used one from a Chevy truck(umbrella type) and that was 7 years ago,and it's working great.


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## Country Boy

Tecumseh didn't call for one in the parts diagrams and I didn't find one in there when I took it apart. I did replace the o-rings for the pushrod tubes and the missing o-rings under the valve springs. It smokes when it is first started, but then quickly tapers off to be hardly noticeable when it warms up. The engine is 40 years old, so some oil consumption is to be expected. The cylinder looked pretty shiny when I had the head off. He only plans to use it to till his garden, so it won't get much use anyway. He has a snowblower for it, but is missing the PTO shaft. He picked it up on Craigslist a few months back for a couple hundred bucks for the tractor, tiller, mower deck and snowblower. It wasn't in running condition at that time, but it did look like someone had the head off before he got it. They probably saw the damage and just sold it to get rid of it. Tractor ran great otherwise. Lots of power and the trans was smooth and quiet.


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## jhngardner367

If it only smokes on startup,I don't see a problem.


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