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-   -   Hard to start when warmed up (https://67-72chevytrucks.com/vboard/showthread.php?t=29759)

Rabid 11-10-2002 03:36 PM

Hard to start when warmed up
 
Truck starts great in the morning. Choke kicks in and everything. Truck doesn't miss or sputter at all when idling and all through my drive to work. HOWEVER, if I stop anywhere enroute to work and shut her off (i.e. gas station for fuel, coffee, cigs, etc..) It is a pain to restart. It acts like it's flooded when I try to restart it. I have to turn it over and over with my foot nearly to the floor to get it to start. So what gives? The thing starts fine when it's cold but after I warm it up and drive it a mile it is a pain in the ass to restart. Also, you can smell the gasoline when I struggle to restart it. Any help is always appreciated.

HOLLEY 600
Electric Choke
(1yr old, no problems....yet)

Gordo 11-10-2002 04:15 PM

It may not be your case but, if the fuel line runs close to the engine before it reaches the carb, the gas in the line may "boil" after shut down (no fan air) and the gas will push it's way past the needle and seat, filling the bowl and flooding the engine. That's one theory, worth takin' a look see.

Fast68Chevy 11-10-2002 04:35 PM

does it turn over irregularly and/or slowly kinda like how when a battery is low charge ?
]

Piston 11-10-2002 05:13 PM

A few things come to mind.
Leaking needle/seat or float level set too high.
Are you positive the choke is releasing all way?

JIMs70GMC 11-10-2002 07:04 PM

Mine does the exact same thing. Starts great in the morning. Runs great. But try and start it 15 minutes after cutting it off and it takes for ever. Then once it does start it runs real rich. Then about 30 seconds later it 's idling good no problems. On mine the fuel line is original. Carb is a replacement Q jet put on by the previous owner(about 3 years ago). One last thing If I let mine cool down (say about an hour) it starts right up, and idles fine. It's only after it has sat for about 10-15 minutes. Not to jump all over Rapid's post, but I'm very interested in the replies, also. Thanks,

chevykid04 11-10-2002 09:34 PM

dont know if it would help but the previous owner of my truck put on a 1 inch carb spacer and that helped with the flooding, still does it every now and then but not too bad, just throw it to the boards and she fires right up

hrc200x 11-11-2002 12:21 AM

I have the same problem on my 454. Starts fine cold, then after it warms up it sometimes will and sometimes won't start... sounds like the battery is low, is this cause the exghaust is too close to the starter/soilinoid? I seen a starter the other day that had a what looked to be factory heat sheild, would that help?

Piston 11-11-2002 12:25 AM

The cooler the starter, the better... Heat affects the windings/brushes inside the starter also causes the soleniod to make poor contact (expanding plastic).

As for the other problems... again, check your float level, choke release, also make sure you dont have any heater hoses touching the fuel line.

67shortie 11-11-2002 01:21 AM

Many things come to mind, but one stands out: choke setting, the plate is closed too far and not letting enough air in when warm.

chevykid04 11-11-2002 10:05 PM

oh yeah , forgot about the starter, check the ground wire to the solonoid, mine was loose, that made it hard to start,oh and if you have headers, that could be making it pretty hot

Rabid 11-12-2002 12:54 PM

Thanks for all the replys. To answer a few of the comments:

No, the starter doesnt hesitate or slow down when I try to restart it.

No, the fuel lines are not to close to "hot" things.

Some of the comments have me wondering though. For example the one about the choke not working properly and the one about the solenoid getting too hot. I replaced the starter about a month ago and when I put it all back together I forgot to put my heat shield back on. About 5 years ago I had put that heat shield on when I was in Texas. It helped out tremendously. However, now I'm in Alaska and it isnt 105 degrees. Matter of fact it is about 100 degrees colder. If it is in fact the solenoid getting too hot that is causing these starting problems I'd be pretty surprised. I can't rule it out though. I'm gonna recheck the carb settings and linkage then put another heat shield on my starter solenoid. One of those two hopefully will solve this.

wingnut 11-13-2002 01:58 AM

I've got almost the same problem, so here's my $0.02. Took off the stock Q-jet and stock manifold off my son's '70 and installed a performer and 1406. Runs great till it gets to operating temp and then it starts to load up a stops and will flood and die if your not careful. Then after it sits for a few minutes, I have to hold my foot to the floor because it floods just sitting there. Called Edle, "it didn't do this before I installed the new equipment", and they told me that it sounded like the carb was getting hot and the gas was percolating out of the carb. I pulled the carb off the truck after it sat for awhile, and the gas level in the bowls was low, but the float level is right on. The needle and seat are also OK. So I guess they might have a point, but it's a little irratating. Also make sure that the exhaust reducers, on the intake manifold gaskets are installed to restrict some exhaust flow to the bottom of the carb.

chevypete396 11-13-2002 06:53 AM

My $.02

I think Wingnut is really close...

I think your carb is leaking fuel and flooding your engine when you stop. As a matter of fact its doing it all the time but when its running it is not causing you any problems, except for maybe slightly increased idle which you have probobly compensated for by readjusting it awhile back. When it sits over night the carb cools and your fuel has plenty of time to evaporate so it isn't doing it in the morning. the odd thing is because your engine starts good in the morning, your carb isn't odviously completely draining like the q-jet did on my 79 blazer when I lived in Alaska (ironicly) and had similar problems. I am not positive why your carb is leaking down from the info you provided so I won't b.s. you whith an answer. Enjoy Alaska and good luck with it... Pete.

snow man 11-13-2002 10:30 AM

carb problems
 
next time you drive it when you get it to operating temp. shut it off pull the top of the air cleaner off and see if you see it leaking inside the manifold while it is sitting. i think you will find the carb is leaking and flooding it out when you shut it off. its time for a good rebuild,just my 2 cents worth. snow man

Rabid 05-10-2003 08:32 PM

TTT

OK, I'm an idiot. The answer was given. The thing is leaking when I shut it off. It seeps into the secondaries. Is this a total rebuild or what? The carb is only a year and half old.

cableguy0 05-10-2003 11:58 PM

first i would try a carb spacer what happening is the fuel is boiling in the carb and being forced into the motor most likely get one of those synthetic spacers because they dont conduct heat like the metals ones do

Rabid 05-11-2003 02:41 PM

Spacer thickness
 
How thick of a spacer? I've seen some pretty big ones and then again I've seen some that are only an inch in height.

lukecp 05-11-2003 10:37 PM

You could just try a 1/4" thick carb gasket if you don't already have one. Get a good Fel Pro gasket. They are made out of black gasket material, and have crush limiters so you can't overtightnen them. They cost about $10 or less at the parts store. They won't have one for your application since GM used Qjets, so you will proably have to go dig around and find one in the Holley pattern. I ended up buying one for a Chevy 366-427 engine out of a C60.

ZOOMY 05-12-2003 09:53 PM

PRESSURE
 
You might want to check your fuel line pressure. Some carbs (needles & seats) won't tolerate high fuel pressure. Did you put a high performance fuel pump on it ???........Zoomy

Mike76251 05-13-2003 12:15 PM

If/when you get that spacer make double sure you don't overtightin the four screws holding the carb down.

I see this a lot and it always warps the crap out of the carb.
I takes a new carb usually to fix it.


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