Lost compression 52 pan

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troll52
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Lost compression 52 pan

#1

Post by troll52 »

Started first time of year 6 kicks ran like champ 2 minutes, pushed down inritcher engine died, attempted restare after third kick lost compression, timing seems ok pushrods acctuating and if anything a little loose timing marks good compression test shows 40 lbs BOTH cans. Any suggestions? :cry:
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Re: Lost compression 52 pan

#2

Post by Cotten »

Troll52!

I would inspect the clutch first.

And then test the manifold anyway.

....Cotten
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Re: Lost compression 52 pan

#3

Post by troll52 »

did test clutch, and manifold. all good, thanks cotton, too strange to figure on my own, and don`t really want to pull down
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Re: Lost compression 52 pan

#4

Post by Cotten »

Troll52!

Lets go to your valve pushrods then; perhaps one is "hung" up and a valve stays open.

It could happen. Honest.

....Cotten
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Re: Lost compression 52 pan

#5

Post by jdpan »

"compression test shows 40 lbs BOTH cans. Any suggestions?"

"perhaps one is "hung" up and a valve stays open."

Compression being the same in both cylinders would make it something common to both rather than a single pushrod being out of whack I would think. Why would the compression suddenly drop in both cylinders is the question. Is it possible that he flooded the engine flushing the oil from the cylinder walls? Just putting it out there for consideration.
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Re: Lost compression 52 pan

#6

Post by troll52 »

I have tried the pushrods checked lifters even pulled the gearcase, all things SEEM normal total ?
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Re: Lost compression 52 pan

#7

Post by jdpan »

"I have tried the pushrods checked lifters even pulled the gearcase, all things SEEM normal total ?"

What are you deeming normal? What are you using for reference, are you using a manual as your guide?
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Re: Lost compression 52 pan

#8

Post by troll52 »

I have tried the pushrods checked lifters even pulled the gearcase, all things SEEM normal total ?
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Re: Lost compression 52 pan

#9

Post by troll52 »

Normal? Yes using book, and experiance. shot oil into cans, 1 pound change. total frustrating, obviously something something simple, both cans at same time, gonna be bald by days end
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Re: Lost compression 52 pan

#10

Post by Huck »

TDC on compression, third gear, tie it down so it can’t move,, just in case. Pull the spark plug and add some air. I use a regulator. Pull the timing plug. Listen at the carb, pipes and timing hole. That should point you to something.
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Re: Lost compression 52 pan

#11

Post by troll52 »

Thanks , tried it all a dosen times. now for no reason than a pan phantom got compression, same as it went, 1 kick. gonna rebuild the carb and hit the wind :D
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Re: Lost compression 52 pan

#12

Post by steve_wood »

When you did the compression test, was the air cleaner removed from the carb? Throttle wide open? If not, that might have caused the low reading (in both cylinders).....
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Re: Lost compression 52 pan

#13

Post by Kuda »

steve_wood wrote:When you did the compression test, was the air cleaner removed from the carb? Throttle wide open? If not, that might have caused the low reading (in both cylinders).....
That's good advice, actually. What's worse, I personally know a guy who fully pulled down a perfectly running engine after he found both cylinders only pushing 30 psi during a routine tune up/check up. After doing the readings several times, he pulled it all the way down to the cases, couldn't find anything wrong. He called me over to give him a second pair of eyes (he's a great mechanic, usually). After checking everything myself, I couldn't see anything either. So I looked at the gauge: the o-ring seal on the spark-plug insert had fallen off. That was the only thing wrong. He felt rather silly after that...

-Kuda
'49 panchop
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