Starter or battery?

LateApex · #1 (**permalink**) 04-03-2003, 08:12 PM

Guys, my GT349.5 running a 289 has a unique problem. My guess is it's the starter. If the car is cold, the starter will crank the daylights out of the (high compression motor) once it gets a few initial turns in. If I run the car, it's warm, and try to restart it in ten minutes, it ain't pretty. I run a bunch of Webers, and in a downhill hard on the brakes stopping for a light session, the motor will stall (lack of fuel pressure--I know, I know I need to deal with that) and when it's time to relight the motor, the starter says, time for a siesta. It'll attempt cranking, but not enough grunt to close the deal. If I let the car sit, and try in 20 minutes, no problem. 2 hours, even better, fires right up.

I am thinking starter has gotten old dealing with this motor. I have made sure battery is fully charged. THERE are no other weak battery symptoms, but battery is certainly 3 years old. I usually run 'em till they can't take a charge.

What do you think?? Sorry this is not a pure Cobra question, as I have no Cobra right now.

petek · #2 (**permalink**) 04-03-2003, 08:27 PM

Well, if the starter works fine cold, then the problem isn't the starter (by itself). Sounds like heat soak. Might be something as simple as too small of cable between the battery and solenoid or solenoid and starter ... or even a poor ground line.

Or it could be that the starter itself is being heat soaked (I seem to remember that Chevy V8s have this problem). A heat shield between the starter and headers might cure the problem.

Just a guess...

niles · #3 (**permalink**) 04-03-2003, 08:48 PM

yes on the above.
Most likely bad, dirty connections or weak ground. When it start OK cold, basics, etc working. When hot, thinks have expanded and changed contact loads/points, connection forces etc and you pick up some high impedience somewhere.
gn

Dwight · #4 (**permalink**) 04-03-2003, 08:50 PM

CHECK INTO A HIGH TORQUE MINI STARTER. COACH MIKE AND I HAD THE SAME PROBLEM. INSTALLED THE MINI STARTERS AND NO HOT START PROBLEMS. BUT FIRST CHECK THE GROUND CONNECTION AND CABLE SIZE. GROUND THE MOTOR TO THE FRAME WITH A GOOD CABLE. HEAT SHIELD DID NOT WORK FOR US. LOCAL HOME TOWN PART STORE HAD THE STARTERS FOR A $130 EXCHANGE.

KobraKarl · #5 (**permalink**) 04-03-2003, 08:55 PM

maybe check your timing for a little too much advance

Junket · #6 (**permalink**) 04-03-2003, 09:52 PM

I would pull the starter and take it to a parts house to be tested belive that it is tired enough with the high compression and the expanding gases in the motor when it hot it could be a little vaper locked.
Ken

cobrakit66 · #7 (**permalink**) 04-05-2003, 12:19 PM

positive cable, check for corrosion inside of the insulation
ron

Bryan Wilson · #8 (**permalink**) 04-06-2003, 05:14 AM

Had the same problem. Wouldn't start when hot like the battery had gone flat. My ground cable went from the battery to the frame and then to the block. This cable was a bit on the light side. I ran a new and much heavier cable from the battery direct to the block, problem solved.
Regards,
Bryan

PNJSNAK · #9 (**permalink**) 04-20-2003, 08:19 PM

Had the same problem. Tried all the above. Backed off the timing abit, no more problem.
Jim

ac289cobra · #10 (**permalink**) 04-20-2003, 10:25 PM

If your running headers and they are close to the starter than you may need a heat shield over the starter. This is a common problem and very frequently on late 60's and early 70's chevys. As for the chevy problem they work great new, give a little time and they won't work hot. Install an aluminum heat shield and the problem goes away.

cobralee · #11 (**permalink**) 04-20-2003, 10:35 PM

I experienced the the same problem with my 427FE. My battery is in the trunk. I had a ground wire going to the frame under the battery. I relocated it to the scattershield. I also got 0 guage wiring and I got a good, new battery. (Interstate). Now, it always starts when hot, but does strain a bit. Now its time to back off on the timing.

Good luck.

68gt500 · #12 (**permalink**) 05-12-2003, 05:34 AM

Next time you have that condition
Disable the ignition and try again:
If it will crank ok ->too much timing advance
Won´t crank ok -> check connections and then get a new starter !

shaps · #13 (**permalink**) 05-12-2003, 06:17 AM

Had similar experience on sb chevy with hdrs. Solved it with mini-starter along with a heat shield. Best of luck!

Roscoe · #14 (**permalink**) 05-12-2003, 07:38 AM

My MSD Digital 6 ignition has a 20 degree start retard built in. Depending on your ignition setup you may be able to buy a separate start retard for your engine which might help your situation. Prevents hard starting and kickback.

Roscoe