green1
Well-Known Member
Prob water, and don't listen to jrdart.
Raw Fuel Out Exhaust
- Thread starter KP
- Start date
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Possible causes:
Valve seal
Valve guide
Valve seat
Valve
Piston compression ring
Anyone else with other possibilities?
I am assuming that the spark plug is firing and the plug wire is functioning.
In reference to my previous post, I had the same indications as you have and so I pulled the valve cover and verified the torque on the rocker arm shaft, that the pushrods were in their rocker arms properly, and that the seals were still installed properly.
Then I pulled the head. I saw a small scoring on the cylinder wall and pulled the piston. I found the compression ring had a small broken area. I also had the head checked at a machine shop to make sure the seals, guides, and valves were ok.
Good luck with what you find. I hope it is easy and inexpensive to fix.
Art
Valve seal
Valve guide
Valve seat
Valve
Piston compression ring
Anyone else with other possibilities?
I am assuming that the spark plug is firing and the plug wire is functioning.
In reference to my previous post, I had the same indications as you have and so I pulled the valve cover and verified the torque on the rocker arm shaft, that the pushrods were in their rocker arms properly, and that the seals were still installed properly.
Then I pulled the head. I saw a small scoring on the cylinder wall and pulled the piston. I found the compression ring had a small broken area. I also had the head checked at a machine shop to make sure the seals, guides, and valves were ok.
Good luck with what you find. I hope it is easy and inexpensive to fix.
Art
KP:
I read the whole thread, and until you mentioned #8 cylinder I thought this might be anything from a 3.5 hp Briggs & Stratton to a V10. I guess I can cross off the Briggs line, and all the 4's & 6's.
So seriously, what is the vehicle? Carb? EFI? Hilborn injected? Give us a clue.
Is the smoke from the tailpipe Black? Blue? White?
B.
I read the whole thread, and until you mentioned #8 cylinder I thought this might be anything from a 3.5 hp Briggs & Stratton to a V10. I guess I can cross off the Briggs line, and all the 4's & 6's.
So seriously, what is the vehicle? Carb? EFI? Hilborn injected? Give us a clue.
Is the smoke from the tailpipe Black? Blue? White?
B.
It is a 360 the inside of the tailpipes have a black build up and I can never tell the color of the smoke but would say it is blue when just at and idel and black when the engine is under a load...
70408dart
70408Dart
What Carb are you running?????? Reason I ask is because I had a bad Holley Street Avenger 770 that did nothing but flood the engine. Turns out the carb was on a recall from Holley. Sent them my old carb and they sent me a new one problem solved for me.
Ok, 360. This is a mopar site, so I will guess it is an LA block mopar, and not an AMC 360.
That means it was installed in a car or truck sometime between 1971 & 2002. So is it carbureted or does it have EFI?
If it has a carburetor, what brand & type? Stock 2bbl, 4bbl, Holley, Carter, Edelebrock, ?
B.
That means it was installed in a car or truck sometime between 1971 & 2002. So is it carbureted or does it have EFI?
If it has a carburetor, what brand & type? Stock 2bbl, 4bbl, Holley, Carter, Edelebrock, ?
B.
Ok, Holley carbs are notorious for running rich.
Float level issues, seat problems, blown power valves, and clogged emulsion tubes will all make it go rich.
Will it idle with the two idle mixture screws gently bottomed out?
With it idling, grab a flashlight & look down the primary bores. Is fuel dripping out of the booster venturis near the top of the carb?
With the engine off, is the fuel level above the bottom of the sight plug threads in the fuel bowls?
B.
Float level issues, seat problems, blown power valves, and clogged emulsion tubes will all make it go rich.
Will it idle with the two idle mixture screws gently bottomed out?
With it idling, grab a flashlight & look down the primary bores. Is fuel dripping out of the booster venturis near the top of the carb?
With the engine off, is the fuel level above the bottom of the sight plug threads in the fuel bowls?
B.
I have checked all this. The floats a good, there are no drips, changed the power valves and it will not idle with the two idle mixture screws bottomed out.
All good suggestions. I even put another carb on it with the same results...
mopar head
Well-Known Member
If #8 cylinder fails the leak down test then pull the head and have it checked.
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