Uneven Riser Temp.

sailsmanship

Petty Officer 1st Class
Joined
Jul 26, 2000
Messages
389
I'm sorry to beat a dead horse but i am at my wits end. I have tried everything I know and what has been suggested and am still at a loss.

Here's the problem again: 1997 5.7L Mercruiser Alpha One Gen II.

Has always ran great and still does.

At the end of last year, a couple times number 8 cylinder has hydrolocked.

This is what I have done and observed:

(1) Two year old fresh water manifold and elbow have been pressure tested
and were fine

(2) Compression is fine across the board

(3) #8 cylinder spark plug is brown with no signs of water wash.

(4) Elbow to manifold gasket is a OEM replacement and shows no crossover breach.

(5) Top of elbow to waterline is within spec.

(6) * Flapper valve was weak and almost collapsed against each other
and replaced on both sides, but there was no pieces missing on either
side.

* I think this might have been the problem because it would only hydrolock
when anchored fishing in rough seas.

Just put it in the water for the season and took it out for a shakedown
to see if everything was tight and put back together right.

Runs fine as usual, but when I compare temperature, feel on top of the
elbows, the problem side is running alot higher than the other side. I have
no idea if it has always been this way, but now I am paying attention to it
because of the problem.

Temperature at the gauge has always been a little high at 175 degrees.
have replaced the gauge and it still reads 175, runs great and has never run higher.

Is this normal, or have I got something else going on ? The only thing I can think of is that possibly I have got some dead Zebra Mussels restricting something somewhere.

Any suggestions ?.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,464
Re: Uneven Riser Temp.

Runs fine as usual, but when I compare temperature, feel on top of the
elbows, the problem side is running alot higher than the other side. I have
no idea if it has always been this way,

Ayuh,.... It's normal for 1 side to be hotter...
 

sailsmanship

Petty Officer 1st Class
Joined
Jul 26, 2000
Messages
389
Re: Uneven Riser Temp.

Even when one side, you can rest your hand on it as long as you want, but the other you can only hold it to a count of five before you have to pull it off?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,464
Re: Uneven Riser Temp.

but the other you can only hold it to a count of five before you have to pull it off?

Ayuh,... At what temperature are You comfortable holding your hand on,..??

Maybe 110?,..??
 

sailsmanship

Petty Officer 1st Class
Joined
Jul 26, 2000
Messages
389
Re: Uneven Riser Temp.

I understand what you are saying, I was just trying to say there is a huge difference in my opinion side to side, and I dont' have a temp gun to tell you exactly the difference.
 
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