LT-155 No Start

[Red Horse]

Well I bought a very clean LT 155 lawn tractor for the wife to tow a cart with. Had a mower and I had the guy take it off. ended up with a charging problem and I replaced a couple of the magnets and that took care of that.

Lately you would hit the key and it would spin briefly then stop-but eventually spin motor and start. Now however hit the key and starter will maybe give less than a half turn and that it is. Pulled starter and it spins just fine. jumped starter solenoid and no difference. Battery okay and even with a jump pac on it, no change-spins a 1/4 or half turn and that is it. Starter switch filthy so pulled connector and shot WD in both ends-no change.

Its been suggested it could be the Pto disconnect switch or the brake interlock switch. Any opinions???
Thx

 

[Kish318420]

Pull the starter and solenoid have it tested at a starter shop. They should be able to load test the torque. Anything can be binding the starter with a load, with no load, no binding.

 

[tomplum]

You could have a tired starter. Jump direct to the terminal with a separate battery. + on the terminal and momentarily hit the the engine at a good ground point with the negative- it will spark. Obviously if it is better there are other issues. I would also see how it turns with the spark plug out and the lead grounded. You could have a bind between the stator and flywheel. And a bunch of ground magnets. . .

 

[Red Horse]

Thx guys-further thought about the PTO switch and brake interlock-thinking about those two items wouldn't it NOT turn at all? It does spin-but not a complete turn

 

[Red Horse]

Update- pulled plug and it spun like crazy. No hydro lock. Excellent mechanic buddy of mine came over thinking might have a bent pushrod. Pulled cover off and everything looks good. He now suspects it somehjow jumped time. He also mentioned that the Kohler engine has a feature that somehow opens valve on initial cranking to facilitate starting?? At least that is how I understand it.

In any case he has a call out to some Kohler "expert" for an opinion.

 

[tomplum]

These won't jump valve timing but they do shear the flywheel key. Many from the factory had flywheels that were not securely tightened. had one from 2004 the other day that had not been apart which had sheared the key and the bolt was easily spun w/ a box wrench. They will still crank over well enough though when this happens. They do have an ACR . Have you done any actual testing? I've had several tired starters on the Command singles. Should you replace it, use the OEM.

 

[Richard001]

Sounds like you need to adjust the valves. If the valve adjustment is to large, the compression release system will not open the valve to release some of the compression and thus the starter can't turn it over.

The fact that when you removed the plug, thus not causing the compression issue, the engine spins over just fine.

Richard

 

[Red Horse]

Thx all for these comments-stay tuned.

 

[tomplum]

Unfortunately, these have hydraulic lifters. A failed ACR problem rests with the cam itself with a very outside chance of a lifter issue.

 

[Red Horse]

Engine by the way is a CV-15S. The Kohler guy came back today and says it has a broken spring-the spring is the thing that provides the compression release on cranking...Make sense?

 

[Dave M7040]

Since you bought this tractor used, it likely has had a battery replacement.

All too often people buy based upon price and end up with a battery without the cranking amps required by aging motors.

I know you said you used a booster pac but success with these in getting a good connection is marginal.

John Deere has this kit to help older tractors' safety switches not hinder solenoid engagement for some models.

Invest a few dollars in these marine battery terminals. Remove the large battery from your car or truck and using the marine terminals connect to your garden tractor.

If it starts fine, go and buy a new battery with the highest CA or CCA you can find.

Dave M7040

Dave M7040

 

[tomplum]

Not a lot of these break the spring on the cam, but it does happen. You won't really know until it is pulled apart. An option though is to put a feeler gauge ~ .015- .020 " in between the exhaust valve and tappet and see if it cranks better then. If so, points to the cam. CCA on the battery should be 250 or above.

 

[Richard001]

Unfortunately, these have hydraulic lifters. A failed ACR problem rests with the cam itself with a very outside chance of a lifter issue.

That maybe true, however, it depends on which head the engine has as to weather the valve lash is adjustable.
See this:

This a page from the service manual.

But I think you are mostly correct that there is an issue with the cam compression release.

Richard

 

[tomplum]

Yeah, they mention that in the manual. They also refer to models w/o an ACR. I've never seen either one myself.

 

[Red Horse]

Again guys thx for the comments. So I pulled the engine and hauled it to my pals shop (He has been featured on American Pickers-you can imagine!)

Hopefully this picture will upload. I guess spring broke and I was not getting the benefit of the ACR-coupled with a weak battery. As to comment on jump pac, I put my Craftsman on it and it didn't do much although it was reading I had 13V. after screwing around I brought my pick up around and jumped it with that at it spun like crazy, fired up and before I could pull it off choke and throttle down it backfired with a bang and that was it.

so 145 bucks for a new one-of course you need the gear and the camshaft! we found a used one on ebay for 45-due in Tuesday. Again.."stay tuned"

 

[beenthere]

Didn't quite follow your description of what happened.. If it backfired, then pull the flywheel and look for a sheared key. Just a guess, but when fixing a B&S engine last year with a broken/bent ACR spring and backfiring, the flywheel key was sheared.

 

[Richard001]

Yes, it's not clear to me either. The photo you attached, is that your engine on the bench?

Richard

 

[Red Horse]

Yes-that is the engine. And after the backfire, flywheel was still intact

 

[beenthere]

............ And after the backfire, flywheel was still intact

"still intact" ? what does that mean?

You maybe then didn't pull it off and look at the key. Just a slight movement of the flywheel on the crank shaft will cause the timing to be off.

Only trying to help.

 

[Richard001]

"still intact" ? what does that mean?

You maybe then didn't pull it off and look at the key. Just a slight movement of the flywheel on the crank shaft will cause the timing to be off.

Only trying to help.

Double what beenthere said. You need to pull off the flywheel and inspect the key.

Richard