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I love intermittent problems... chirp sound disappeared in 1700 engine

absolutely sure the noise comes from #2 and #4 cylinders.

removing/installing spark plugs in #1 and #3 doesn't change the noise.

removing/installing spark plugs in #2 and #4 makes the noise disappear/reappear.

Ok, I figure I have a leak somewhere.

It can be at 3 places:

1)exhaust valve 2)intake valve 3)between head and cylinder

for a test, I decide to put some oil into cylinder #4. Put the spark plug back in. Adjust #4 exhaust valve completely out (so exhaust valve does not get opened). This creates a situation where the #4 cylinder will a)intake b)compress c)not exhaust

I used a wrench on the alternator nut, cranked the engine until it locked up. cranked harder. completely locked up.

I was looking for a leak.. perhaps the oil was too thick to escape through whatever leak exists.

Ok, test failed to give me any good data.

rough adjust exhaust valve so it is opening again. crank the engine to let some of the oil out of cylinder. replaced spark plug....

no more noise from left side of engine!

ok, so either

1)oil still exists in "crack" that is leaking pressure 2)oil lubricated whatever spot was chirping

arghhh

Reply to
jboothbee
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Trouble is, the chirp was not the problem - just one of the symptoms or indicators! I just read your compression figures and you've got trouble, my friend, and it aint the yong'uns playin' pool! (Yes, I AM that old!) I THINK you need to re-analyze your valve adjusting sequence. I THINK you are adjusting out-of sequence. You may have something backwards in your brain as to which is when and what the rotation of the crankshaft vs rotation of the distributor rotor is. Something does not add up. Hopefully it's a stupid mistake like I'm suggesting. I've done it a couple times, but that was in the distant past. (I make much stupider mistakes now!)

Anyway, the compression readings are all too low. Figure out the reason before you run the engine much. Was the case split? (Trying to open the opportunity for cam-to-crank timing to be wrong)

BTW- compression test: All 4 plugs out for first 4 tests. Ground coil high tension lead securely or disconnect power from coil. Throttle wide open (stick something somewhere to hold it that way!) Crank until highest reading on gauge. Write 'em all down. Now put a plug in #1 and test #2 then vice/versa Now put a plug in #3 and test #4 then vice/versa Any changes? Now squirt the equivalent of a teaspoonful of oil into one cylinder. Spin it over a couple turns. Check the compression on that cylinder. It should be identical to what you got before the oil or very close since your top end is new. If it is much higher than before, I'd guess a broken ring, maybe from not end-gapping the rings properly. Try each cylinder - one at a time, with all the rest of the plugs out - with the oil test. Now you have some comparison data to ponder.

Turn engine to where TDC marks line up. Check rotor to see whether it's pointed at #1 or #3. Check valves for the coresponding cylinder - they should be loose. Hope I haven't offended and maybe have helped some. -BaH

Reply to
Busahaulic

Or sound is gone due to re-setting tappets? Just my 2 cents.

Reply to
Bart Bervoets

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