Fouled plugs..

Hi All,

This is a continuation of my post in the intro section -Original Post . Figured this is a more appropriate place for this discussion. I'm very new to the automotive fix-it scene, so please be patient with me

Just picked up a '67 CJ5 and having some engine issues. Its a four cylinder with a 3 speed(as much as I know so far).

Hopefully this helps...


Was running real rough when I got it and wouldn't get over 15 mph. Replaced the plugs which were covered in black powder(carbon?) and it ran pretty darn good for about 20 mins and then when back to runnin real rough. Check the plugs and they are covered in carbon again. The first cylinder seemed to have a little oil on the threads?

Did a compression test and here are the results:

120
112
107
124

I'm thinkin that 107 isn't lookin too good :? Any thought on what to try next?

Thanks in advance,

DonC

 

adjust the following: choke and air/fuel. also check the exhaust for carbon buildup/blockage.

 

go grab you some of those no-foul's that you thread onto the end of your spark plug from autozone

 

Nah, not oil fouled IMO. Oil fouled looks like a black, sticky, wet residue. Oil on the threads is probably coming from the outside, like the valve cover gasket. Carbon (mixture too rich) is black and powdery dry. Adjust the idle mixture and choke, or look for something in the carburetor that's adding too much fuel, like the float set way too high, or bad gaskets.

Lots of sites with spark plug pics on the web - this one came up first: http://www.gnttype.org/techarea/engine/plugs.html

<edit> Compression looks ok to me - not great, but ok.

 

Thanks for the replys. The fuel in new, although mixed with a little that was in there previously. Will try adjusting the air/fuel and check the choke. Glad to hear the compression isn't too bad, was hoping to hold off and major engine work til the winter months.

DonC

 

Got any pics of the whole jeep? It looks really nice.

 

OK, checked the choke and it seemed to be stuck partly closed. Fixed that and adjusted the idle and a/f screws. Took a while as I didn't know if "IN" meant more or less fuel. After playing with it a while, I came to the conclusion "IN" meant less fuel (hope thats right ). Anyway, got it idling pretty good, but its raining so I can't see how it is on the road .

If the crappy aftermarket tach that is hanging under the dash is correct, it's idling at between 1200-1400 rpm. Any lower and it starts running rough. Is that too high? I'm thinkin it might be.

Thanks,

DonC