problem with fieldmarshall

[mikern]

Hi All. I've posted a couple times about our new off grid exerience, got a ? tonite.. We shut off the FM for oil check and sunday is laundry day,so we do that with the grid, we went to restart the FM and it has no, zero, compression. it shut down nomally, all fluids are good. I'm leaving for work now, and the boys are pulling off everything attached to the head so I can pull that in the morning. Before I do that, are there any suggestions about the problem or fix? I'd appreciate any ideas, thanks Mike

[potter]

Id try a sharp tap on the valves might only be a bit of carbon not letting them seat.

[billswan]

Mikern
When you crank it over you should be able to hear the leak, if it was carbon holding open a valve you should hear the leak in the intake or the exhaust.

If the rings were stuck or no oil on them you might listen to the crankcase for the sound, remove the reed valve and listen there as someone cranks it with the decompression off. Pull the injector and add a squirt of oil then reinstall injector if you think the rings are leaking.

 Are you sure the valve clearance is set correctly?

Head gasket blown? Should have water leaking out if that happened.

Billswan

[M61hops]

Hey Mike, I second what potter and billswan said!  Correct diagnosis is a talent that comes in very handy for engines, and other things too  !  For me it works well to go slow and observe (see,feel listen) what is going on as you rotate the engine.  Do the valves go up and down, injector creak, air go in and out the correct ports at the right times, etc.  I check everything I can and usually have a theory of what's wrong before I start taking something apart.  At least these engines are so simple that it is a sure bet you can get them running again no matter what went wrong!  Good luck!       Leland

[mikern]

Thanks for the tips guys,I'll get off in about 2 hours and will try them to see what happens. I probably jumped the gun when I had the boys (son in law & grandson) pull of the rad, intake and exhaust, got pushed for time, oh well, live and learn I hope. I'll keep you all posted, thanks, Mike

[apogee_man]

I would also look closely at the compression release just to make sure it's not holding the valve open when it's supposed to be in run mode.

[mikern]

We tried bout everything to get compression back, no luck, so went ahead and pulled the head off.The first surprise was the injector, it was carbon caked! the exhaust valve and piston top also had a pretty decent build up of carbon,, bore looked beautiful, not the slightest ring ridge. so were cleaning up/grinding the valves today, and hopefully back together tonight or in the morning. I did some figureing, closest guess is the the FM has about 2800 hours of pretty steady running. The only thing is has ever burned is WVO.  I;ll keep everyone posted on pregress, thanks, Mike

[Chris R]

Stuck Valves.

This is what I have done when I have a sticky valve problem and have to get my Lister VA back online ASAP. This is when just tapping on the valve does not work.

Take off the rocker arms. Tap the valves (With the caps on), while spraying with WD40, Liquid Wrench, diesel, kero, or what ever you have. Once you get some movement check for compression by cranking the crank shaft very slowly. Just check for compression, don't crank through. If still leaking air, (Still stuck), normally through the exhaust valve, I do a "In the bush" valve job. Attach an electric drill to the valve stem. Push down on the valve to open, Spay the valve stem with what ever oil you have and try to get the oil to run down between the valve stem and guide, push up and down on the drill a couple times, with the drill running, keep spraying oil, then and check for compression again. A couple goes with this method and problem solved.

"In the bush" decoke. Dribble kerosene in the intake, very carefully to avoid over speed, and be ready to use the decompression release if needed. Keep dribbling kero until you have run about half a cup of Kerosine through the engine. Kerosine helps cut through the carbon build up. I usually follow up doing the same thing with a couple cap fulls of Marvel Mystery Oil.

Good luck,

Chris R

[mike90045]

"In the bush" decoke.
 Dribble kerosene in the intake, very carefully to avoid over speed, and be ready to use the decompression release if needed. Keep dribbling kero until you have run about half a cup of Kerosine through the engine. Kerosine helps cut through the carbon build up. I usually follow up doing the same thing with a couple cap fulls of Marvel Mystery Oil.   

Isn't kerosene about the same as diesel, but no lube quality  

  I thought a fog/mist/spritz of water, and running a pint thru a hot engines intake over several minutes was a good alternative to steam cleaning the chamber.

[Tom]

I've had good luck with the MMO too.

[Chris R]

For some reason kerosine cuts through the carbon build up and is what the original Lister manuals say to use (Parafin oil). Kero cuts right through the diesel/oil scum that builds up inside the crank case.

Chris

[Doug]

Loctite gasket Chisel will remove anything that sticks to the head or piston...

[mikern]

The Fieldmarshall is up and running again as of last night. Took new valve guides and a valve job, and FOREVER at the local machine  shop. I'll start doing the water injection weekly and hopefully avoid this happening agian. Thanks to all of you for your suggestions, Mike

[Chris R]

Mike,

Glad to hear you are up and running,
Chris

[Oiler]

When my 6/1 lost compression at about 1300 hours, i had to get it started and tryed a propane torch.Got it going and gave it a small amount of propane for about five minutes.
After running for  six hours it was shut down. Next day it started at once with full or nearly full compression. Added a little propane again for five minutes and it has now done 700 huoers with no problems and still has planty of compression.