AMC 360 Vaporlock

[Beaujeep]

Howdy. New subscriber and need some help.
Recently purchased a 1980 CJ7. It has an AMC 360 engine, Holly 4bbl Carb.
I'm having issues with the engine and vapor locking. The motor takes a bit to get started, but the trouble begins after I get her going and get up to about 35-40 mph. If I start out slow, generally I have no problems, but when I step on the gas and get after it, the engine will surge or will shut down. Any suggestions???

[John N]

It sounds more the carb is not tuned to the engine. See if you can find a local who knows how to tune the carb; it means getting into the power valve, changing out the squirter (might not be the right term, but what we called them), re-jetting and some new gaskets.

[berserker]

Check your fuel line routing to the carb. Make sure it is not running too close to the left exhaust manifold when it exits the fuel pump (this should be a steel line, not a rubber hose).

If you have headers, trace the fuel line on the left frame rail just below the firewall--that is an area that can get too close to the exhaust as well.

[Beaujeep]

I had that done. Had it in w/mechanic two weeks ago, he adjusted the carb. My thinking is the carb is too big for that engine...Its a Holly 750-850, they couldnt tell for sure. When it dies, it acts flooded. Another thought is its the fuel pump...Or fuel lines getting too hot.

[Beaujeep]

What is the best way to ensure the fuel lines does get too hot...Is there a good way to insulate them???

[rixcj]

Unless it's a modified 360, a Holley 750 or 800 is too big. I run a Holley 600 on my 360, and I also ran the 600 on my 401.

I ran my fuel line like this... it's the line that snakes from the top of the frame rail, down the outside of the rail.





It's covered in a fire-resistant wrap.

I haven't done it yet, but I'm going to build a steel shroud over the part of the line that's on the outside of the frame, so that if my front tire ever came off, the tire won't rip the line off.

Plans also include extending the steel line right up to the fuel pump.

This routing keeps the line enough away from the headers. I never have vapor lock issues.

I have no fuel return line, either.

Rich

[Beaujeep]

Thanks for all the help!! I"ll give it a shot and see if that takes care of it.