69 hot start

[Nick Kalogeras]

I have recently completed a ground up resto on a 1969 350/350 vette. I was having a spark problem until I rebuilt the distributor and found the magnet was toast. I have a new magnet in it, it will start when it's cold but not when it's hot. It only gives me a slow dull turn over. I had it timed properly, so I don't think it's that. The original starter was not with the car. I had to buy a Delco replacement and put it in. Any suggestions on what to try next would be most appreciated. Thanks.

[Pat K.]

Re: 69 hot start

I had the same problem with my BB '69. Called John Pirkle (number is in the archives) and he set me up with an original starter that he beef's up to work when it gets hot. I changed my battery to an Optima too, and have not had a single problem.

[Kurt B.]

Re: 69 hot start

Nick,
I have the exact same problem with my 68 smallblock coupe restoration ands have replaced everythingwith new parts includign the starter. I just recently received an e-mail from John Pirkle about his reworked, beefed up, starters and I am going to have him rebuild mine with this technology. My thoughts are what good is my restored Corvette if it won't start. I had John do some alternator work for me years ago and he is the best.
I am hopeful he will solve both your and my problem.
Kurt

[Reba Whittington]

Re: 69 hot start

I had the same problem with my big block '72 when it was hot. John's beefed-up starter has solved the problem. I drove it on the road tour a few years ago in 95-degree weather with no problem at all.

[Lee S.]

Re: 69 hot start

I have an extensive series of posts the past two weeks on "no/slow crank" start problems on my 1974 Big Block. For a long time, I thought this was hot soak and considered all of the usual items... starter, heat shields, etc.

Back in April, I replaced both negative battery cables and the battery (which was 12 years old). The negative cable under the RS motor mount was extensively corroded. Look at this very closely. The rear negative cable was replaced just for insurance. This helped for awhile.

The problem worsened over the summer to a point where the car would only start if battery was at absolute full charge. Leave the doors open for 15 minutes to clean and vacuum or attempt restart when hot resulted in slow crank, no crank, or just a click from the solenoid.

I decided to pull the solenoid for further inspection (it had some loose terminal posts) and found positive battry cable corrosion at the joint of the cable to the eye that connects to the solenoid. Further investigation found evidence of a previous repair (cable wraped in electrical tape). More importantly, the cable core was brittle and black for a section of approximately four inches back from the solenoid. It was apparent that regardless of other problems, this cable was bad.

I replaced the cable. I wish I could also say it was as simple as that since the cable is almost six feet long and snakes up and over the propshaft tunnel and transmission case. Some will say they can do this faster, but I estimate I have twenty hours labor in this... all with the car on jackstands. Search for the previous posts under "positive battery cable" or e-mail me. This board was a tremendous source of guidance through this and helped me recognize that there was not going to be any magic solution except to remove exhaust system, transmission crossmember, and other components. I also replaced the solenoid, again as insurance.

This past Sunday, we took a 250+ mile road trip (round trip) with some friends. There were various stops along the way (in July on a similiar trip we came home on a flat bed to the tune of a $275 tow bill). I can't believe the difference. It seems like the engine is going to jump right out of the car when restarted. I also previously noted that my lights would dim (excessively) when the power windows were lowered or raised. Now when lowered, its like you dropped the glass down an elevator shaft. Going up? You better get your arm out of the way.

Summary... make sure you do a through diagnosis before investing in expensive starters which may not solve the problem. Measure voltage at the battery and solenoid before and during cranking. Observe other symptoms like power window operation. I never put this together until afterwards.

Good Luck. I'll try and post a photo of the worn out cable. There is a big contrst to a good cable.

[Clem Z.]

some battery cables are

copper plated aluminum and these are not near as good as pure copper. make sure the replacement are 100% copper

[Lee S.]

Re: some battery cables are

Yes - looking at cable strands of the old cable, the aluminum cable APPEARS to be cooper. As Clem points out, this is copper plated aluminum. Believe me, if you do this job once, you never want to do it again.

[Clem Z.]

the weight of the cable will tell you if

it is aluminum or copper as the pure copper one will be heavier.

[William C.]

Re: some battery cables are

I believe virtually all the OEM GM Corvette cables from the 1970's were "Copper Clad Aluminum" in construction. The ends were covered with solder during the manufacturing process to prevent corrosion, but after 30 years, any degree of salt exposure will cause the aluminum to disappear and what is left to conduct current is a batch of little hollow copper strands. Not Good!

[Clem Z.]

if you want realy good cables

make them from electric welder cable as this will carry the current(amps) better than ready made cable. we always used it when we move the battery from the engine compartment to the trunk in drag race cars with very high CR,13:1 and better engines.

[Terry M.]

[Patrick H.]

Re: some battery cables are

Terry,

The original battery cable on the 72 is ABSOLUTELY aluminum.
I'm hoping to replace it in the next 1-2 days, and will post a picture.

I'd love info on how to use the original ends to make a larger cable for "daily use."

Patrick

[William C.]

Re: some battery cables are

By the way, the actual printing on the jacket of the cabels under discussion was in fact "COPPER CLAD ALUMINUM"

[John H.]

Re: some battery cables are

I made all the battery cables for my rear-battery project cars (Cobras, Grand Sport, highboy, etc.) from 2/0 welding cable, with heavy copper lugs; Eastwood still sells a great tool to crimp the copper lugs to welding cable - have had mine for many years.

[Terry M.]

COPPER CLAD ALUMINUM

Thanks Bill -- I do not have an example of one of those cables to look for the exact lettering. I had to work from memory.
BTW: The metallurgy lab where I worked from 1964-1968 helped develop the process of cladding the aluminum wire with copper. I wish I could remember who paid for the research. Our specialty was lubrication of metalworking processes, and lubricating this one was a neat trick.