L100 TDC

[snoopy]

Can anyone specify exactly where it is? The Yanmar manual states the flywheel, but I'm looked over and over and can't see any marks.

Otherwise, how else can I find TDC (to confirm the exhaust valve).

Cheers, Andrew

[BoxerOtto]

if you cant find any timing marks you may have to pull the head off and set a dial indicator on the piston to zero it out and make your own marks on the flywheel and crank case. did you have flywheel key issues earlier on? if you have fuel vapor coming out of your intake then either the intake valve is tight or you had a stuck valve and the piston helped push it back and is now bent. a loose or falling out valve seat from being over heated or timing gears have slipped on crank or cam. lots of carbon build up on valve stem could lead to a stuck valve ,but usually exhaust. are you running pump diesel or adding anything to it?

[snoopy]

Running pump diesel no additions. I put easy start in the air intake and she fired before dying, so my focus as of this moment is fuel delivery. Failing that the head will be coming off. Hopefully not too big a job on this little diesel?

Cheers,

Andrew

[andrewaust]

If you have the injector out I'd place something soft "plastic tube like lube spray tube" down the injector hole and keep the rocker cover off and see when the inlet and exhaust valve rock at an equal point that the piston is at TDC, that will be on the exhaust inlet cycle, if the engine is the electric start version the marks if I remember rightly are on the inner side of the flywheel "ring gear" which means the starter motor or whatever is over the hole needs to come out. Once again I'm not fully sure of this and will check when I get time.

The delivery valve should start to come up just before TDC, then we get into talking spill timing and all sorts of things. It probably wouldn't take me long if I had the engine in front of me to get it running, it's so bloody hard when it's not close to figure out what is going on. If your kicking it over by kick starting, you'll know if it has good compression, as it's just about impossible to get it to turn over if your to close to the compression stroke.

Keep us posted, I'm sure it's something simple.


Andrew

[thundercougarfalconbird]

this might help, but you also need to verify that the cam drive has not moved ,i.e. the key on the cam gear or crank gear have not shifted.
the only other thing we have seen for a no start / hard start with a 406cc clone is a bent con rod, the piston was off and had too much leakage, but if you tortured it and heated the intake air it would run poorly with limited power.

http://imageshack.us/photo/my-images/70 ... es036.jpg/

http://imageshack.us/photo/my-images/70 ... es035.jpg/

[snoopy]

I'm pretty sure compression is good - I can stand on the kickstart if I don't use the decomp and she wont turn.

[andrewaust]

Yes sounds like compression is good, like T.C.F said, it might need more investigation. They are a great little engine when they are going, but a pain in the ass when they aren't !!

Keep us posted

A