no compression

hi i have no compression on my lister d i have had the engine apart as in restoring it i have had the piston out when i put it back in a oiled bore and i put some down bore when it was in and left it to soke down like people had been saying is it one of the valves sticking open or something else please help

brooko wrote:hi i have no compression on my lister d i have had the engine apart as in restoring it i have had the piston out when i put it back in a oiled bore and i put some down bore when it was in and left it to soke down like people had been saying is it one of the valves sticking open or something else please help

were the rings loose in the piston grooves? did you check valve clearances? about 15 thousands of an inch i think. also check valves are not sticking in the guides. also valves might need cleaning and grinding in.

Ok the rings were lose when piston was out but when i put it back in all seemed good the valves could do with a clean ill try that

When you fitted the piston did you move the rings so as none of the gaps were inline?

Stu.

Did you put the spark plug back in?

When you say 'no' compression, is it like there is no plug there (spins freely) or is it just low (a bit of resistance every other turn of the crank)? If the valves are just a bit dirty but still move I'd expect a little bit...

Knowing whether there is none or little can help with diagnosis.

many thanks for the tips i removed the piston again and made sure rings were ok put it all back together and found i had compression but as soon as i refitted rocker shaft there was no compression again after further inspection i found there was no play on the exhaust rocker i set the rocker to the correct gap an dcompression returned so the problem was the exhaust valve was not shutting off. i cranked her over took a couple of cranks but it fired up sounds very knocky for my likeing is this due to were i have cleaned everything and the oil is not properly got all around the engine

When you put it together, did you dip each part in oil?

If not, you should've...

was there much play in the pistons conecting rod bearings/shells,
also when you turned its crank to top and bottom dead center was there much movment slope in the piston up and down the bore
was the oil level to overflowing the filler
was/is the engine oil grey silver or with metal bits in it like filling
oil on your finger from sump is it thick and slippy or thin and soaks into your skin quick loss of slipping betwen fingers
kev

Have another go at re-setting the tappets as there might have been a bit of dirt or something stuck in the valves. Have you greased/oiled all the points that need doing? There will be a few parts where the oil will take time to get to. Did you clean out all the oil ways with a bit of welding rod or similar?

Stu.

check for play on the big end bearing...bottom of piston conrod, mine was badly worn and had a lot of play, replaced it and the one i got from stationary engine parts was much better, i also totaly cleaned the rocker shaft and made sure grease holes were clear so when i re packet with grease i know its ok, also check timing, not sure about statics as its new to me too but on other engines i have worked on if ignition happens at tdc it can make some funny noises