Adjusted valves according to merc manual and engine wont run

itchyfishnv

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now im only reading 60 PSI on both cyl 1 and 2... Was 110 when the compression test was done last week. Thoughts?
 

Scott Danforth

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Cylinder 1 and 2 are still too tight
 

itchyfishnv

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So, my plan tomorrow and this the last plan before it goes away until spring time... Warm up the engine, take the valve cover off... back out the valves for cyl 1 and 2, one valve at a time 1/4 turns in 10 second intervals? Is there a particular order to adjust them when the engine is running? I didn't see anything in the merc manual but figured id ask to be on the safe side... Lets say I get back to zero lash... does that mean my lifters are collapsed?
 

alldodge

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So, my plan tomorrow and this the last plan before it goes away until spring time... Warm up the engine, take the valve cover off... back out the valves for cyl 1 and 2, one valve at a time 1/4 turns in 10 second intervals? Is there a particular order to adjust them when the engine is running? I didn't see anything in the merc manual but figured id ask to be on the safe side... Lets say I get back to zero lash... does that mean my lifters are collapsed?

No order to adjust, and zero lash is where the lifters a rattling. You should have a bit of a miss going on as well. The start tightening the nuts a 1/4 turn at a time. So as you tighten it will start to make a noise, wait to stop, then turn another 1/4 turn until you get one turn. If you cannot get a full one turn then you do have a collapsed lifter and it needs replaced
 

itchyfishnv

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So I'm tightening the nuts, not loosening them? If they are too tight as Scott said, wouldn't I be loosening the nut?
 

Scott Danforth

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there are youtube videos on setting valve lash. 90% of them are small blocks, however the process is the same.

start motor, at idle, remove valve cover, put a rag over the lifters (or have oil everywhere), loosen the nuts until you hear the lifter rattle, then tighten slowly until the rattle goes away. once the noise subsides, tighen 1/2 turn.... move on to next. watch your fingers, and keep an eye on how much oil you have on your shirt.

or run motor, get warm, remove valve cover, back off nuts and go thru the non-running process
 

itchyfishnv

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Aug 10, 2016
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Still the same readings on the compression... calling it quits for the season. Pulling out the engine in the next couple weeks, I'm going to have a complete rebuild done. It's 30 years old, it's time. Thanks for all your help, everyone.
 
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