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Discussion Starter #1
olds 468, my engine has been runnin great all summer. yesterday i pulled it out of the garage checked all the bolts linkage yada yada.. i cranked it over and started her up.. if standing behind the boat looking at the transom, at idle the left header has a small flame come out of cylinder #2 every so often. Now ive only done one valve adjustment this year and thats when i installed the cam. The motor sounds great and doesnt seem to have any issues. i do smell fuel though the exhaust makes my eyes water lol... Im gonna do a valve adjustment today just incase, gonna swap out plugs as well and check the timing other then that anyone have ideas of what it could be??

never really ran into this with any engine before...
 

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Discussion Starter #3 (Edited)
Sounds like unburned fuel igniting in the header pipe , pull the plugs , keep them in order and see what they look like Pics ? Tom
Thats what i was thinking as well, but it hasnt done this all summer.. My plugs do foul very quickly maybe 2 trips to the water and i need new plugs lol.. so im guessing they are fouled and im gonna toss some new ones in.. Hell when i take em out they are always "wet" lol!
im still gonna do the valve adjustment...

its .025" for every 1/4 turn right?? proper preload is .050???? correct me if wrong.. running harland sharp roller rockers.
 

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What the Hell is That?
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Thats what i was thinking as well, but it hasnt done this all summer.. My plugs do foul very quickly maybe 2 trips to the water and i need new plugs lol.. so im guessing they are fouled and im gonna toss some new ones in.. Hell when i take em out they are always "wet" lol!
im still gonna do the valve adjustment...

its .025" for every 1/4 turn right?? proper preload is .050???? correct me if wrong.. running harland sharp roller rockers.
I am by no means a pro, especially with olds. I would look into why your fouling plugs so quickly. Also when you say they are "wet" is it gas? oil?

If i remember your running eddies for carbs. They are notorious for clogging easily. Maybe your getting too much fuel in the combustion chamber, wet plugs and unburnt fuel is igniting in the pipe.

like I said, not a pro just throwing ides out there.
 

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steelcomp was here
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Thats what i was thinking as well, but it hasnt done this all summer.. My plugs do foul very quickly maybe 2 trips to the water and i need new plugs lol.. so im guessing they are fouled and im gonna toss some new ones in.. Hell when i take em out they are always "wet" lol!
im still gonna do the valve adjustment...

its .025" for every 1/4 turn right?? proper preload is .050???? correct me if wrong.. running harland sharp roller rockers.
.050 per turn...
Soulds like you may have fouled plugs.
 

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olds 468, my engine has been runnin great all summer. yesterday i pulled it out of the garage checked all the bolts linkage yada yada.. i cranked it over and started her up.. if standing behind the boat looking at the transom, at idle the left header has a small flame come out of cylinder #2 every so often. Now ive only done one valve adjustment this year and thats when i installed the cam. The motor sounds great and doesnt seem to have any issues. i do smell fuel though the exhaust makes my eyes water lol... Im gonna do a valve adjustment today just incase, gonna swap out plugs as well and check the timing other then that anyone have ideas of what it could be??

never really ran into this with any engine before...
Sounds like a plug not firing...sometimes starting the motor when the exhaust is cool, running it for 5 seconds shut it off and CAREFULLY check pipe temp with your hand will show what cylinder are having a problem.....but it sounds like you have other problems...weak ignition/plugs to cold heat range/carb rich......

And i see you have and olds motor like me....Shouldn't have to adjust hydraulic lifters...even with other than stock rockers...and adjusting hydraulics without the motor running can cause problems...i usually turn the idle as low as it will go and still run, back the adjuster out till it clatters. slowly turn it in until the clatter stops, and then slowly turn it in another 1/4-1/2 turn in...and it will be hard to hear with open exhaust.....
I have a couple car mufflers i stick in my exhaust...or you can back off the adjuster until the rocker arm gets a little loose...turn the nut in until the motor rpm just begins to drop. and slowly tighten no more than another qtr. turn....
And hopefully you have a roller cam...or have been very careful about using oil with zinc additives..i bought a used/low hour jet boat motor for mine and the cam is on it's way out....like 10 lifters with flat faces and
cam lobes with shiny noses...

I have a tunnel ram with 2 660 holleys...idles 750-800 rpm in gear in the water (v-drive) never have to rev it to 'clean it out' plugs come out light brown after 1/2 hour of idling or hard running...

And don't be sniffin to much of that exhaust stuff...even if ya run the good gas and it smells good...it ain't good for YOU:D

thanx
mike
 

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Some guy
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olds 468, my engine has been runnin great all summer. ...
My plugs do foul very quickly maybe 2 trips to the water and i need new plugs lol.. so im guessing they are fouled and im gonna toss some new ones in.. Hell when i take em out they are always "wet" lol!
Your two statements don't work together.

You need to sort out why you are fouling plugs that quickly, either carburetion or ignition, something is not right if it's fuel fouling.

The other possibility might be oil fouling?
 

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Discussion Starter #9
it was fouled plugs..went ahead and changed em the problem went away.. I know im runnin way to fat the plugs smell of gas and are wet lol. Ive changed metering rods a few times i think im just gonna have to drop a jet size.

ive got way to much fuel. but hey it runs really well. ;)
 
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