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Hard Starting 69 GTX #971919
04/12/11 12:25 PM
04/12/11 12:25 PM
Joined: Jun 2005
Posts: 89
Colorado
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CaptainGTX Offline OP
member
CaptainGTX  Offline OP
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Joined: Jun 2005
Posts: 89
Colorado
I own a 69 GTX 440 4spd which I've restored as close to factory original as possible. Not unlike a lot of high performance cars of that vintage, it takes a lot of cranking to start it. If it sets more than about 6-8 hours, I can count on having to grind it for a full 30 seconds before starting. The weird thing is:

This hard starting occurs even if I start the car, let it run for a couple minutes & shut it off. I kinda expect this to happen after I've driven it long enough to get everything up to operating temperature. Then I figure the gas is boiling out of the carb and maybe the fuel line next to the block. But the fact that it happens even after it's not gotten hot is puzzling.

I have had the carb rebuilt by two different shops - one a regular carb shop & the other a mopar mechanic - no difference. I've replaced the fuel pump under the assumption the diaphram was leaking - no difference. I replaced the fuel line when I restored the car, the return line is original but not blocked & the entire fuel system is stock. It's almost as though something is pulling a vacuum on the line back to the tank, but all the venting seems to work properly. Occasionally, I get a storng gasoline smell in the garage after I've driven it, but haven't been able to tie it to any particular method of operation.

I've lived with this problem for the 5 years the car has been restored. Some mopar mechanics just say its the nature of the beast. And that its the incompatability of a carbureted engine and today's blends of gasoline, but it seems it should be possible to improve starting. The gasoline shouldn't be evaporating from a cold carb setting on a cold engine. The car runs fine. Anyone experienced this (particularly on a cold engine) and have a thought as to how to get it to start better?

Thanks,
Rich in Golden, CO

Re: Hard Starting 69 GTX [Re: CaptainGTX] #971920
04/12/11 12:44 PM
04/12/11 12:44 PM
Joined: Jan 2005
Posts: 3,344
Central TX
roe Offline
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roe  Offline
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Joined: Jan 2005
Posts: 3,344
Central TX
Ive read on here, where timing settings have affected how hard/easy an engine starts. Have you thought about a mini-starter or do you want to keep the stock style? My mini-starter turns my motor over much faster and gives me easier and quicker starting

roe



1971 Plymouth Satellite
408/904 8 3/4 3.23 SG
Re: Hard Starting 69 GTX [Re: CaptainGTX] #971921
04/12/11 01:31 PM
04/12/11 01:31 PM
Joined: Mar 2008
Posts: 5,746
Ontario, Canada
Dodgem Offline
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Dodgem  Offline
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Posts: 5,746
Ontario, Canada
Pull the breather and watch to see if gas is running into the intake after running.

It always takes two good pumps to get them going cold!

But warm should be 1/2 pump and hold 1/3 open.

Maybe the carb needs a good rebuild. a good one sometimes they need a lot of work done right!

Re: Hard Starting 69 GTX [Re: CaptainGTX] #971922
04/12/11 02:53 PM
04/12/11 02:53 PM
Joined: Feb 2003
Posts: 10,178
Someplace you aren't
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SomeCarGuy Offline
I Live Here
SomeCarGuy  Offline
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Joined: Feb 2003
Posts: 10,178
Someplace you aren't
Weak starter or bad ground. Maybe add a big ground and see if it cranks faster and starts easier.

Timing off

Timing chain loose

If it happens cold but not after sitting for week(s) then boiling gas isn't it.

Any drivability problems? Wondering if it may have a huge vaccum leak, but you would notice other issues. My car starts at the bump of the key or at least coughs.


I want my fair share
Re: Hard Starting 69 GTX [Re: SomeCarGuy] #971923
04/12/11 05:31 PM
04/12/11 05:31 PM
Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
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RapidRobert Offline
Circle Track
RapidRobert  Offline
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Joined: Nov 2003
Posts: 36,040
Lincoln Nebraska
Next time when it is at the point where it acts up, b 4 you crank it take off the air cleaner & open choke & see if it has a good squirt of gas from the AP and hold the coil wire 1/4" from a safe ground while a helper turns the key to start. Basic stuff but might point you in the right direction


live every 24 hour block of time like it's your last day on earth
Re: Hard Starting 69 GTX [Re: RapidRobert] #971924
04/13/11 09:35 AM
04/13/11 09:35 AM
Joined: Sep 2006
Posts: 277
Palmyra, NY
6
63stabamatic Offline
enthusiast
63stabamatic  Offline
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Joined: Sep 2006
Posts: 277
Palmyra, NY
My 69 GTX with the stock AVS has had problems starting it's whole life. The new gas makes everything worse as it evaporates quickly, even sitting at a cruise night for a few hours. While you could have some other issues as others have said this is the starting procedure recommend by the outfit (Pony Carburators) that restored the Carter AVS. Run the starter without pushing down the gas pedel for 10-15 seconds to get gas into the carb. Set the choke. Now the next step you change depending on how long the engine's been off. For my car pumping it 4 times was perfect after letting it sit all winter. Pump once for a couple days, don't pump at all for the day before etc. You have have to play with this. Since using this procedure It's never failed to start. I hope this helps. Maybe Rocky can weigh in on this too.

Re: Hard Starting 69 GTX [Re: CaptainGTX] #971925
04/13/11 09:44 AM
04/13/11 09:44 AM
Joined: Dec 2009
Posts: 1,023
pa.
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dan9 Offline
super stock
dan9  Offline
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Joined: Dec 2009
Posts: 1,023
pa.
I would try a temporary electric fuel pump first to make sure it is fuel related.

Re: Hard Starting 69 GTX [Re: CaptainGTX] #971926
04/13/11 01:47 PM
04/13/11 01:47 PM
Joined: Mar 2007
Posts: 3,275
West Coast, USA
jbc426 Offline
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jbc426  Offline
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Joined: Mar 2007
Posts: 3,275
West Coast, USA
Does your accelerator pump shoot in fuel when you open the carb when cold?, when hot? If so, test the + voltage at the coil(Not at the spark plug tower). It should be around 6 to 8 with the key on(key in Start 1= run = through the ballast resistor) and 12+ with the starter cranking(Start 2 = Cranking).

Mopars use two "12v" feeds to the coil, Start 1 & Start 2. This was to boost the coil output when cranking to reduce hard starting, and run the car on reduced voltage to increase the longevity of the coil etc.

If you only have the reduced voltage from the ballast resistor when cranking, you may not be getting the bypassed straight battery voltage(Start 2 = 12v) when cranking. This can cause the starting problems you are having.

What is your initial and total timing?


1970 Plymouth 'Cuda #'s 440-6(block in storage)currently 493" 6 pack, Shaker, 5 speed Passon, 4.10's
1968 Plymouth Barracuda Convertible 408 Magnum EFI with 4 speed automatic overdrive, 3800 stall lock-up converter and 4.30's (closest thing to an automatic 5 speed going)






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