Carb Issues

So.... I have a '68 cj5 with the 225 and it won't start. This all began in december or so. It would start just fine when the engine was cold, but once it got warm it wouldn't restart. At first it would just happen now and then, but now it won't even start. I did do an HEI conversion in January, but I am farily sure that is not the source of the problem since it started right up as soon as I put the HEI in.
I think that it might be a choke issue or something related to it, but I am really not sure. I have checked the fuel pump, it is delivering fuel. The fuel filter is not clogged. I have strong spark on all 6 cylinders. The timing it set to 5 degrees btdc. The PO said he rebuilt the carb last august just before he sold it to me.
Any help would be great as I am about ready to toss the whole thing and go pursue other hobbies. :?

Judson

 

I had the same problem you described. Turned out to be a bad float valve in the carburetor. It would start when cold but not after it had warmed up. Some of the cleaner used while cleaning the carb apparently was left behind and damaged some seals. Anyway, you may want to look at a flooded carb.

 

Is the choke closeing when its cold? Does it open when it warms up? Is it closed when its hot?
Right now it won't start... I would make sure the choke is closed. If it is not... then either pump it alot while cranking or poor a small amount of fuel down the carb. If it fires.... then you know its loss of fuel. If it does not... you have other problems.
Could be badly flooded? Or a bad Timing chain? OR?? Very hard to diagnois on here without hearing it.
But, try these things and get back to us un the results.
Reaney

 

so here is the latest update. I checked the choke to make sure it was closed when cold and it was. I checked the float for smooth travel and it seemed to be fine. The fuel level appeared to be at the right level, at least it was at the same level as another rochester that runs fine. I pulled the carb to make sure the exaust recirculation holes were not plugged, they were fine.
I tried the pumping the gas a bunch while cranking to no avail. I didn't try the pouring gas down the carb, as it was the same as pumping the gas pedal a bunch.
When you say float valve are you refering to the float? I am not sure what part I should be looking at for the float valve.
If it is not a lack of Fuel problem what else could it be? Thanks for all the responses so far, I hope I can get to the bottom of this before my planned Moab trip in 2 weeks.

 

Are you sure the carb is not flooding? If something is lodged in the seat preventing the float valve from closing you end up with flooding. Same if the valve itself is damaged.