No compression cylinder 2 and 3

500dollar744ti

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Re: No compression cylinder 2 and 3

You will also want to investigate why the head gasket blew so it doesn't happen again. Timing, fuel mixture, correct plugs, etc...
 

Golson Molson

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Re: No compression cylinder 2 and 3

The previous owner admitted the main hose to the t-stat blew and he overheated the engine. It was repaired at a marina along with several other parts relating to it and was given the O.K. Have the bills. It's an older bowrider and was bought strictly to teach the kids how to waterski but also had to be able to carry at least 5 people.
 
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Golson Molson

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Re: No compression cylinder 2 and 3

Most parts are in. .024 off the head. Ran a tap through the head bolts and applied perma-tex sealant, tightened to 100lbs ft torque patterned to the manual. Rubber boots for the exhaust have been replace and back flow is still on order. Will have to replace the t-stat housing as one of the bolt holes is badly cracked.

Now waiting for the exhaust/Intake gasket and back flow to finish. Hopefully in tomorrow.018.jpg019.jpg020.jpg021.jpg022.jpg
 

achris

More fish than mountain goat
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Re: No compression cylinder 2 and 3

What is a 'back-flow'?
 

Golson Molson

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Re: No compression cylinder 2 and 3

What is a 'back-flow'?

It is a rubber flapper in the exhaust to prevent water from back flowing into the engine when you power down. Apparently it will disintegrate if your engine has been overheated.023.jpg
 

Golson Molson

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Re: No compression cylinder 2 and 3

Well it started but ran rough. Checked compression still zero in 2 and now zero in 4. Low compression in 1 and 3 but suggest there is no break in time and the engine was still fairly cold. Will recheck valve settings tomorrow. Could the timing be off as well? Suggestions anyone.
 

achris

More fish than mountain goat
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Re: No compression cylinder 2 and 3

Even cold, cylinders should read SOME value, not 0.... It's sounding like you have multiple problems, and (you're not going to want to hear this) you might need to pull the engine out and strip it down to find the problems. The only other thing I would be checking is the valve adjustment. If they are too tight, it could be holding a valve open, and that's where the pressure's going....

Chris........
 

Bondo

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Re: No compression cylinder 2 and 3

Even cold, cylinders should read SOME value, not 0.... It's sounding like you have multiple problems, and (you're not going to want to hear this) you might need to pull the engine out and strip it down to find the problems. The only other thing I would be checking is the valve adjustment. If they are too tight, it could be holding a valve open, and that's where the pressure's going....

Chris........

Ayuh,.... That's My guess,...
 

Golson Molson

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Re: No compression cylinder 2 and 3

Took the valve cover off and adjusted the exhaust valves for #2 and #4 back 1/4 turn checked for clearances, reinstalled cover, check for compression and sure enough, equal compression in all cylinders. Fired the boat up and bingo, first crank it started. Phew.:joyous:

Noticed the Temp gauge was pegged so I shut it down. Any ideas on the temp gauge?
 

Bondo

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Re: No compression cylinder 2 and 3

Took the valve cover off and adjusted the exhaust valves for #2 and #4 back 1/4 turn checked for clearances, reinstalled cover, check for compression and sure enough, equal compression in all cylinders. Fired the boat up and bingo, first crank it started. Phew.:joyous:

Noticed the Temp gauge was pegged so I shut it down. Any ideas on the temp gauge?

Ayuh,... Ya had the muffs on it, 'n the water runnin', Right,..??

If so, change the Impeller,...
 

achris

More fish than mountain goat
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Messages
27,468
Re: No compression cylinder 2 and 3

...Noticed the Temp gauge was pegged so I shut it down. Any ideas on the temp gauge?

If there was water flowing and the engine didn't really get hot, then do the diagnostics on a temp gauge...

1. Disconnect the wire from the sender. Gauge should read dead cold.
2. Ground sender wire to engine block. Gauge should peg hot.
3. Ground wire to sender body. Gauge should peg hot.

If there all check out, then replace the sender.

Chris......
 

Golson Molson

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Messages
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Re: No compression cylinder 2 and 3

Ayuh,... Ya had the muffs on it, 'n the water runnin', Right,..??

If so, change the Impeller,...

Yes everything on and water running through. The water although hot I would estimate about 140 degrees. Steaming but you can still put your hand under it. The temp gauge is simply pegged, with or without the ignition on or the boat running. I'm now thinking the temp. sensor in the t-stat housing.
 
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