Rotating crankshaft

[palomoto]

Hi all. I would like to check the valve lash of my new to me 2005 John Deere 110tlb. The manual says to rotate the crankshaft via the crankshaft pulley. Not much room to get to the pulley and I can only imagine the force that would be needed. Pulling out the injectors would remove the compression resistance, but is something like that necessary for the average shade tree mechanic to safely rotate the crankshaft to perform my checks? Any other tips? Thanks!

 

[rScotty]

Hi all. I would like to check the valve lash of my new to me 2005 John Deere 110tlb. The manual says to rotate the crankshaft via the crankshaft pulley. Not much room to get to the pulley and I can only imagine the force that would be needed. Pulling out the injectors would remove the compression resistance, but is something like that necessary for the average shade tree mechanic to safely rotate the crankshaft to perform my checks? Any other tips? Thanks!

Glad you brought the subject up. How do others usually check the valve lash? I'd like to know too.

It's time - past time - to check the valve lash on both our TLBs. On any kind of gasser I've always just pulled the spark plugs and rotated the motor via the nut (or bolt) that holds the front pulley on. But pulling the injectors is a bigger deal than spark plugs.

Then I check each cylinder, rotating the crank in the normal running direction and checking the exhaust valve just as the intake valve fully closes... and the intake valve lash for that cylinder when the exhaust valve is just beginning to open. That's the right crank position for max lash on any engine I've ever seen, easier to find than TDC of the compression stroke, and generally saves at least half the number of manual crank rotations

And frankly in the past I've always done this job when I had the motor disabled somehow and just sort of ignored it other times. But right now I'm in the lucky position of having not one but two real good diesel engines with such high hours that my conscience is telling me it's gotta be time to check the valve lash.

And the problem here is that both our TLBs are such unusually easy starting machines that I'm kinda reluctant to stick my arms in there to rotate the crank. A good starting diesel always has a little bit of fuel at the injector. OTOH, I just hate to pull injectors for no other reason but can't see a way around it.

How do other folks handle this?
rScotty

 

[4570Man]

Pulling the glow plugs is usually pretty easy. At least the ones I’ve done. Is there no bolt somewhere to put a breaker bar on?

 

[palomoto]

I am a bit more comforted knowing I am not the only one! I'm with you on it seems pulling the injectors is probably not hard, just one more item that I cold foul up on the removal and installation and also best practice on my machine is to replace the nozzle rings and heat protectors whenever the injectors are removed. While I don't have a high hour machine and the engine seems to run good, I really have no reference for what good actually is and the prior maintenance of the machine is an unknown.

 

[4570Man]

Glow plugs and injectors aren’t the same thing. Glow plugs are easier to pull.

 

[palomoto]

Glow plugs. That is a good suggestion. Only things is I'm not sure my 110tlb has them! But I sure will figure that out now...

 

[4570Man]

My quick google search says it does but I don’t know that for a fact.

 

[palomoto]

Nice of you to help figure out if I have glow or no glow. I'll update the forum once I verify.

OK, verified for the 2005 John Deere 110tlb with the Yanmar 4TNV88 engine, no glow plugs. Manifold heater for cold starting.

Best I can figure in my case anyway, is to remove the hydraulic pump coupling attached to the crankshaft pulley, find the biggest breaker bar I've got, socket on the pulley nut, and give it the 'ol heave ho. Sound about right?

 

[thepumpguysc]

A lot of x you can put a socket on the alternator & put pressure on the belt while you turn the alt..
BUT.. when you get to a "compression stroke", you have to let it bleed off, then proceed..
It works.
If the belt just spins & spins.. tighten it up..
If it impossible to get to the crank nut & the alt. trick wont work.. you can always pull the starter & use a screwdriver on the flywheel teeth..??
Personally, I have a "remote starter button".. I hook it up, DISABLE the run solenoid & BUMP the engine w/ the starter button until I'm close & then use the alternator belt..

 

[palomoto]

OK, got the crankshaft to rotate safely and valve lash adjustment accomplished. As it turns out, I was able to rotate the crankshaft by alternating 13mm and 16mm box end wrenches on the crankshaft pulley/main implement hydraulic pump coupling and watching the timing marks on the flywheel. I went slow letting the compression bleed off each wrenching until I had all the rotation I needed. Wasn't really that hard, just never done it before so did not know what to expect. Not much different really than a gasoline engine. Anyway, I adjusted 7 out of 8 valves as these were at or a little beyond maximum clearance (0.012") leaving the #3 exhaust valve alone as it was spot on. All valves now a 0.008". Know the theory that the clearances should tighten up with machine hours, but this was not so in my case. Again, don't know the prior maintenance, valves could have been set sloppy if adjusted at all before. Think they were as I could see evidence of wrenching on the rocker arm cover bolts. Don't know if the machine runs any different, but now I have a baseline established and now much less afraid to attempt again someday! Thanks all for the suggestions and hope this helps someone else out.