# LT4000 Mongrel?



## needdoe (Jan 3, 2016)

Hi there, I am trying to get to the bottom of my lawn tractor. It is a Craftsman Mod# 917.255692 Ser# 081892S 019824
It looks like the manual, a LT 4000 which is supposed to have a 14 horsepower Kohler in it. It however it has a Briggs & Stratton 
42E707 1631-01 19.5 horsepower engine.
My problem is when I put on the #130969 belt from my manual my mower deck is always engaged and the belt burned up quickly. When I tried to put on a belt that matched a tractor with that engine It was 95" at 1/2" and far too big. My old belt which is very thin, (certainly not a 1/2"), and stopped working is still whole and measures at 93" for a 1/2" belt in the belt measuring machine at Tractor Supply Company. I have been told the belt for my LT4000 should be 92.5" but a 93" my work. Could the engine have been swapped and have a little bit bigger pulley that is throwing off the original belt size from working? Or did these grey LT4000 ever get that 19.5HP engine? My local shop told me they gave me the OEM spec belt #130969 for my machine but cannot tell me it's actual length nor can searspartsdirect Thanks


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## RC Wells (Dec 26, 2008)

Obviously a replacement engine. The Kohler was a single cylinder and likely had a different bolt pattern that placed the engine at a different distance from the deck drive pulley. Sometimes the wise thing is to simply walk away.


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## FredM (Nov 18, 2015)

Most bolt patterns in the vertical shaft engines up to 19HP are interchangeable, I recently changed over a 17HP Kohler (blown) and fitted a 19HP Briggs with no bother, Briggs, Honda, Kohler and Tecumseh (12HP from experience) are interchangeable and most have the same diameter PTO shaft of 1" diameter so the drive pulley can be swapped over.

Do you have a manual clutch or electric ?, if electric, the belt is always tight, -- and you say that the new belt burned, if that is the case, look for a seized idler or spindle pulley shaft.


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## wjjones (May 28, 2010)

Route a string through all the pulleys in the drive system mark it measure, and allow for a little deflection. Sometimes they strech a bit when they are worn.


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## needdoe (Jan 3, 2016)

Thank you very much everyone,
I did check and found nothing seized or impeding and it does not have an electric clutch. I also did wonder about the bolt pattern moving the engine and thought of trying the string but wondered if that would go to deep into the pulleys. I did find out the pully on the motor is the same as the original at 5 1/2". I saw a mower while at a local junkyard and pulled the belt off. It measured 92.5" at TSC as I have been told my original should be. They unfortunately only sell 92" or 94" generic belts and those didn't work. The 92.5 seems to fit properly,(so either I'm stupid or my local shop is), Testing has been hampered by carb issues now. 
Could anyone tell me if i should have fuel gravity flowing when I pull the hose off my fuel pump on the front of the carb. I do not but do get minimal fuel if i drop the hose as far down as I can. Fuel filter replaced.
I would love to walk away if I could only find a mower deck for JD 314 somewhere closer to the Northeast that I can pick up as most that are advertised require. Thanks Again


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## RC Wells (Dec 26, 2008)

Does your deck mounting and belt routing look like this diagram?









If so, the distance of the deck to the engine drive pulley by tweaking the adjustment nuts on the suspension arms and the threaded ends of the front links. That will likely solve your belt length issue. Most NAPA auto parts stores can provide a belt in any length you specify.

As for the fuel line, most pump equipped systems have the tank located such that fuel will not free flow from the line at the pump. The pump must pulse to pull fuel from the tank. Those pumps also fail after a few years, but are inexpensive to replace.


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## needdoe (Jan 3, 2016)

RC Wells said:


> Does your deck mounting and belt routing look like this diagram?
> 
> 
> 
> ...


Thank you RC,
That looks like it has one more pulley than mine. I have just the 2 mandrels and and only 2 idler pulleys.
Can you tell me if the "pulse" is generated from the crankcase? When I pull the hose from the engine I do get results I would call pulse. It is not straight vacuum but does seem to have vacuum intermittently. This sound like it should be normal. I need to check the action at the other end of the hose today. I did replace the rectangular vacuum pump gaskets, diaphragm and springs on the front of the carb last year. The engine has been"hard cabled", both throttle and choke are totally manual. It has always run steady but needed to be fully choked always. Lately it will run but surges as almost violently to what seems to be being starved and then just in time getting gas. I would not have thought this "pulse " pump could pull fuel all the way from the back but I guess it should so I will check that vacuum line and I guess my old pump 
work. 
Thanks again for the help,
TK


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## RC Wells (Dec 26, 2008)

The pulse fuel pump usually operates from the pulse of the crankcase. Sounds like your carburetor is in need of a through cleaning and/or rebuild.

The throttle cable should be hooked to the governor which in turn would operate the carburetor butterfly. Trying to operate the throttle directly to the carburetor will cause the engine to starve for fuel and surge (or quit) every time it is loaded down by the mower.


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## Bill Kapaun (May 8, 2007)

You can get the Owners Manual here if you don't have one.
http://www.managemyhome.com/mmh/lis_pdf/OWNM/L0805065.pdf

Original Engine was a Kohler CV14S-1445. engine had a fuel pump & 15 Amp charge system.
That specific Briggs is found on a few Craftsman tractors. Maybe more than in my incomplete database-
*917.-
258572
258661
258670
258671
259570*
These have the 3 Amp charge w/AC lighting lead.
The deck belt is listed as an AYP 130969. 92.5"X1/2"


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## TecumsehBriggs (Jun 17, 2011)

Measure every belt you buy. I've been getting belts that are an inch to two inches too short, even though they have the correct part number on them. 

Go to Napa & ask for an A91 belt. It should measure 1/2"x93". If it's not, try another of the same number.

Sent from my SAMSUNG-SM-G850A using Tractor Forum mobile app


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