Engine Hot....hard to start
Tech Contributor
Joined: Aug 1999
Posts: 14,381
Likes: 6,396
From: At my Bar drinking and wrenching in Lafayette Colorado
You have 2 issues:
1. Your timing is way off.
2. Your fuel in your accel pump wells is boiling after shutdown. This will flood out the engine on hot-start and cause hard start problems.
Get your total timing up to 36 so you have initial in the mid-teen range. Then put a reflective heat shield under that Holley to keep the fuel from boiling out of your accel pump wells and flooding the engine after hot shut-down.
PS - You haven't plugged or eliminated your fuel return line, have you...?
1. Your timing is way off.
2. Your fuel in your accel pump wells is boiling after shutdown. This will flood out the engine on hot-start and cause hard start problems.
Get your total timing up to 36 so you have initial in the mid-teen range. Then put a reflective heat shield under that Holley to keep the fuel from boiling out of your accel pump wells and flooding the engine after hot shut-down.
PS - You haven't plugged or eliminated your fuel return line, have you...?
Last edited by lars; Mar 5, 2007 at 10:54 AM.
Instructor
Joined: Dec 2002
Posts: 222
Likes: 0
From: Leander TX
or Vapor lock. After reading all the posts, I'm still not clear on if it is turning over more slowly or not when hot. If you put an after market fuel pump on and capped off the fuel return line.. do a search for a post by Lars on how to set up the fuel line to use the return to help avoiding vapor lock.
-F
Advanced
Joined: Dec 2006
Posts: 52
Likes: 0
I have just been through the same situation. It turns out that my heat risor valve had been welded in the closed position. Someone thought they where fixing the rattle but instead maid problems. I had gone through everyting I could think of. This fixed my problem. Check the heat risor arm on the passenger side and make sure it's not closed off.
Safety Car
Joined: Jul 2002
Posts: 3,770
Likes: 3
From: St Louis MO
Another thing to check: see if there is fuel dribbling out of the boosters or air bleeds after you shut it down when the engine is hot. I had the same problem you do and I noticed that there was fuel bubbling out of the air bleeds after I shut it down when hot. I used just the plastic/rubber portion of a holley heat shield and that seemed to cure it.
Thread Starter
Melting Slicks
Joined: Jan 2003
Posts: 2,713
Likes: 31
From: Shreveport LA
LA Events Coordinator
Another thing to check: see if there is fuel dribbling out of the boosters or air bleeds after you shut it down when the engine is hot. I had the same problem you do and I noticed that there was fuel bubbling out of the air bleeds after I shut it down when hot. I used just the plastic/rubber portion of a holley heat shield and that seemed to cure it.
2. Your fuel in your accel pump wells is boiling after shutdown. This will flood out the engine on hot-start and cause hard start problems.
Then put a reflective heat shield under that Holley to keep the fuel from boiling out of your accel pump wells and flooding the engine after hot shut-down
Then put a reflective heat shield under that Holley to keep the fuel from boiling out of your accel pump wells and flooding the engine after hot shut-down
2 questions: 1) When looking at the carb, where are the boosters or air bleeds? and 2) are these 2 quotes related to the same problem.
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