302 hard starting when warm

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Jun 24, 2005 | 04:00 PM

pburress

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From: Wichita, KS

302 hard starting when warm

I recently purchased an ’82 F150 with a 302 v-8. The motor has been rebuilt within the last 10k miles but was not idling well when I got it. A carb rebuild helped with the idle and now it runs well.

When cold, it starts quickly. But if it's warms and I let it sit from 5 minutes to half an hour, it’s hard to start. It turns over for up to 5 seconds before firing, I have to give it lots of gas to get it to fire, and it sputters when it first starts. After starting it is fine. Any clues what this might be?

Thanks, Phil

Last edited by pburress; Jun 24, 2005 at 04:04 PM.

Jun 24, 2005 | 04:39 PM

Kemicalburns

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From: Bend,OR

sounds like its running a tad rich. might bump your timing up a little as well

Jun 24, 2005 | 09:12 PM

pburress

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From: Wichita, KS

I adjusted these air mixture screws several times, the last was this afternoon. Each time I start two full turns out (counterclockwise) from fully closed. From what I've read I expected to have to turn them in clockwise (leaner, right?) from here but this seems to lower the idle and cause it to run rougher... I think I ended up over two turns out on both screws today...

On the timing, that's another question. If I set it by the specs listed inside the engine compartment, 9deg btdc, the motor seems to have no power under acceleration. If I turn the dist. clockwise and advance it the idle raises and it has better low end power. I don't know anything about the rebuild or if it has a stock cam in it still. Is there a way to set the timing in the ballpark without a light or knowing what it should be?

Jun 24, 2005 | 11:14 PM

Artistictouch

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Ford didn't put heat sheilds on their starters which is likely the cause. Fords 302 is a tight engine placing the starter closer the exhaust manifold than other makes. This usually decreases the life of fords starters on the 302. Try a heat sheild on the starter and see how well it fires after a good running...you may be surprised.

Jun 25, 2005 | 09:48 AM

pburress

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From: Wichita, KS

The starter turns over fine, at a norman rpm... It just doesn't want to fire up.

I still think the answer may lie in the timing/fuel mixture. Any help on making these adjustments is appreciated. I will check for vacuum leaks also.

Jun 25, 2005 | 11:17 AM

munrow

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From: Miami, FL.

"Ford didn't put heat sheilds on their starters which is likely the cause. Fords 302 is a tight engine placing the starter closer the exhaust manifold than other makes."

Does your rig have Headers? Could compound the above problem.

After a few mods on my 351 (see sig.), I had the same exact problem. Turns out that I had the fuel line at an improper angle with it kind of arched above the level of the carb intake. I was flooding the carb every time I shut it off, and the fuel in the line drained down into the carb.
After re-positioning the line so that it was below the carb intake, I can start right up every time.
Munrow

Last edited by munrow; Jun 25, 2005 at 11:31 AM.

Jun 25, 2005 | 11:17 AM

Kemicalburns

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From: Bend,OR

when your timing it are you plugging the vacum advance? you can adjust the timing with a vacum gauge as well. but a timing light is the easiest. for something that you may use a lot you can get em cheap for under 25bucks. you should probably run that motor at 10-11*btdc.