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Drivetrain => The Nailhead => Topic started by: mdkd on May 31, 2013, 10:08:36 AM

Title: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: mdkd on May 31, 2013, 10:08:36 AM
All

I have a 65 GS Convertable and Hard Top and both have Air Conditioning with fuel tank return lines intact.

Both cars start just fine when warm but take a bit of cranking when they have sat a day or so.

If I dribble some fuel in the carb cold they fire right up.

The Convert has a manual chock and the HT is stock and looks like it works correctly.

Both fuel pumps are the crimped on style not the screw together type that I think is correct for the 64-65 400-401-425.

In looking at page 100 and 103 of our electronic manual I see something called an Air Dome on the fuel pump of a screw together style which I don't have on mine. Is this for the 300 or 400?

Could this be my problem?

I am looking to purchase a 65 screw together fuel pump for correctness and keep the old ones as spares for the road.

Is the screw together type AC 40371 correct for 65? Do other brands I see as 40371 look the same as AC?

I know I have laid out a bunch here but I am trying to be correct, if possible, and dependable, a must, if I can.

Thanks
Milton
Title: Re: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: mdkd on June 04, 2013, 03:26:43 PM
All

If nobody else has had this problem consider yourself lucky.

Hopefully everyone else is not having the same problem and or there is no solution.

I have been using nonoxygenated fuel not corn gas but who knows.

I'm going to try a new fuel pump and see what happens.

Keep ya posted.

Milton
Title: Re: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: WkillGS on June 05, 2013, 09:30:11 AM
The AFB carb on my '66 Special is a tough start after sitting a few days. I figured the carb was going dry, but I haven't investigated the situation yet. One of these days I'll pop the top to see if there is still fuel in the bowls.

My '65 GS had the screw-together pump. My 66's have the crimped-on style.
Title: Re: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: dsags on June 05, 2013, 11:29:31 AM
Think Walt may be correct. Try checking the fuel bowls just before starting or maybe a different square bore carb. Believe the AFB's have a reputation for this sort of thing.
Title: Re: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: Brian on June 05, 2013, 12:33:16 PM
I don't think you are going to get rid of that problem.  As Dan said, it is normal for the fuel to evaporate out of the bowl on an AFB.  Every one I have ever had exibits the same behavior.  If you start it every day, it always starts right up, but if it sits a couple days, the fuel is gone out of the bowl and you have to crank it until the pump gets enough fuel in the bowls for it to start.    Same problem with the rochester 2bbl. on my 66 Skylark.     Only way you are going to get it to start right up every time even after sitting several days is to convert it to electronic fuel injection! 
Title: Re: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: nut465gs on June 05, 2013, 04:03:50 PM
I've always experienced some extra cranking time needed if the GSs have sat for a week or more.  Could be gasoline evaporating from the carb. Could be a weak fuel pump diaphragm that lets the gasoline seep back down. Could be that it's time for new spark plugs for a good hot spark. I just figured that it was the nature of the beast.

John
Title: Re: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: mdkd on June 05, 2013, 05:24:42 PM
Thanks guys

And here I thought I had a problem.    :BangHead:

I now have my answer.   :hello2:

Once Spring comes DRIVE MY GS's REGULARILY UNTIL I PUT THEM AWAY IN THE Fall.   :sunny:

I don't know how it could get any easier!   :icon_salut:

Once again 65GS.com to the rescue.    :occasion14:   

Thanks again for all your input

Milton
Title: Re: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: WkillGS on June 06, 2013, 08:50:46 AM
My blue '66 doesn't have a problem with lack of fuel on start-ups..... the electric fuel pump takes care of that! Been on there since about 1980 when I built it. I put it on to fix the vapor lock problem.

Perhaps there's a way to tee in an electric pump and only turn it on for a few seconds to assist starts.

Then there is the manual method..... use a small bottle (solvent bottles work well) to fill the fuel bowls thru the vent tubes.
Title: Re: Good Warm Start poor Cold Start and Fuel Pump ? on 65GS
Post by: mdkd on June 06, 2013, 11:04:58 AM
Walt

Thanks for the suggestion.

My wife suggested I take the squeeze bulb off our boat so people don't look at her like an idiot when she tries to start the car.

The electric pump could make her half right.

I must also apologise

The last line of my previous post was supposed to have said.

Seriously, thanks again for all your input.

Milton