rebuilt 289 trouble starting sometimes

[just0610]

:craz
Just had my 289 rebuilt . Since the rebuild it gives me trouble starting on occasion. When it acts up it seems to have no spark when turning over. Plenty of battery power. Then when I hold the gas pedal to the floor the engine slowly starts fluttering like it is flooded with gas and sometimes it will stall right after. I changed the points and condenser, plugs and wires, and has a 1 year old Edelbrock 650 4BBL carb on it. Any idea what else it could be? Checked the timing and was good. This issue was not happening before my engine was rebuilt. Most of the time the engine fires right up. Also, it does seem to have a slight miss but very slight. Thanks for any input everyone!

 

[Anonymous]

is it hot when you have trouble? do you have a spacer between the carb and intake? needles sticking in the carb?

 

[apollard]

Mr Ears is on the right track - sounds like heat soak.

 

[blue65coupe]

I would agree.

 

[TB350]

+1 on the heat soak. Sounds like a lot of carb for a 289. Do you have a big cam and heads on it? kip

 

[daveSanborn]

Checked the timing and was good.

Are you sure? It sounds like a timing issue to me.... It was starting/working fine before the engine was rebuilt and now you're experiencing a "hard to start" problem. If you have "heat soak" now, you'd have had it before the rebuild also.

Double check the timing and report your procedure for obtaining and the results.

 

[66gt350]

Are you sure? It sounds like a timing issue to me.... It was starting/working fine before the engine was rebuilt and now you're experiencing a "hard to start" problem. If you have "heat soak" now, you'd have had it before the rebuild also.

Double check the timing and report your procedure for obtaining and the results.

+1.

I did that to the wife's '65. I had the timing way...way...way too advanced. The car started fine at home, but after a quick stop, it barely started. I set the timing where it belongs and starts easy every time now.

Did I mention that the timing was slightly advanced?

 

[johnpro]

has a 1 year old Edelbrock 650 4BBL carb on it.

To my knowledge, Edelbrock does not make a 650 cfm carb. It's either 500, 600 or 750 cfm. My guess would be a 1406 which is 600 cfm.

I'm with the others ... either too much advance, too much heat under the carb (no phenolic spacer) or both.

 

[gotstang]

To my knowledge, Edelbrock does not make a 650 cfm carb. It's either 500, 600 or 750 cfm. My guess would be a 1406 which is 600 cfm.

I'm with the others ... either too much advance, too much heat under the carb (no phenolic spacer) or both.

I think the new Carter/Edelbrock AVS are 650cfm?

 

[camachinist]

Is this a cold start or warm restart issue or does that vary too?

If variable, I'd first try a known-good carburetor and attempt to replicate the issue.

Generally, a rebuilt engine, especially one where power output has been increased, runs hotter externally, even if coolant temps appear normal. As has been mentioned, heat transfer to the carburetor can cause a number of issues, including vapor lock and overwhelming of the needle and seat, sending raw gas down the main jets/venturis and into the intake manifold, causing hard starts. A phenolic carb spacer, as mentioned, will help. Also, running a switched electric fuel pump can help too, as they bleed off pressure when shut off and are nearly impervious to vapor lock.

Your description sounds carb-related to me...

Pat