#1 cylnder is dead

X

xleoxchavezx

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Aug 14, 2006
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#1 cylnder is dead on my volvo penta aq125 a. this is after having the carberator rebuilt and a valve job and resurfacing done to the head. there seems to be compression in that cylnder but not sure because i am having trouble locating a compression guage long enough to reach. also the boat overheats after about ten minutes with the ear muffs on would this have anything to do with #1 being dead
 
bomar76

bomar76

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Joined
Jun 27, 2002
Messages
1,963
Re: #1 cylnder is dead

Sounds like you had the world's worst Valve Job done...drag that boat back to whoever screwed it up, could be a lot of things they FUBARed to cause this:

1. Bad head gasket (poor installation, incorrect torque, idiot reused head gasket,etc)
2. Cracked head
3. Bad mill work on head
4. Combination of 1,2, and 3

or was this a DIY job?

What was going on the precipitate the head and carb work?

Tell us the WHOLE story...
 
Don S

Don S

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62,321
Re: #1 cylnder is dead

Before you blame it on anyone or anything, find out if there is compression.
How do you know it's a problem with number one?
Who did ALL the work? I understand you had the Valve job and resurfacing done by a shop, but who put it all together?
Are you sure it's not a fault with the valve adjustment?
How about electrical? Bad cap, rotor, points, plug, wires you name it.
 
C

calwldlif

Petty Officer 1st Class
Joined
Aug 16, 2002
Messages
348
Re: #1 cylnder is dead

So what happened you
put the timing light on #1
and you don't get the
blinky light :%
 
X

xleoxchavezx

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Re: #1 cylnder is dead

i finally found a compression guage and #1 has no compression at all so this leads to the rings being completely wiped am i correct in assuming this
 
Reel Poor

Reel Poor

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Re: #1 cylnder is dead

xleoxchavezx said:
i finally found a compression guage and #1 has no compression at all so this leads to the rings being completely wiped am i correct in assuming this
Click to expand...

No,,,,Even without any rings it would build a small amount of pressure.

You need to do a cylinder leak test to find out what the problem is.

Possibly miss adjusted valves, faulty valve job, or missing lobe(s) on cam shaft.

 
Don S

Don S

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Messages
62,321
Re: #1 cylnder is dead

#1 has no compression at all so this leads to the rings being completely wiped am i correct in assuming this
Click to expand...

No, that is not a good assumption. Could be a valve stuck open, or not seated. Rings usually will give a low reading, but will come up when about a tablespoon of oil is added to the cylinder.
A stuck or unseated valve will not change with oil added.
What you need to do is a leakdown test on the cylinder. Bring it up on TDC and pressurize with are and listen for the leak. Carb or exhaust would indicate intake or exhaust valve. Valve cover oil fill cap making the most noise would be the rings or a hole in a piston.
 
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