Starter heat soak FYI

[eightbanger]

Well my Ebay starter packed up after 4 years, heat soak from the headers was the prime suspect, I replaced it on recommendation with a Powermaster starter, a more pricey unit but was assured the short life of my last starter would not be repeated. Now 2 mths down the line I began having the same problem, slow engine cranking, and after a long drive little or no cranking at all until it cooled a bit, so back to the shop for a replacement, but this time I purchased a heat shield and clocked it closer to the block. I dropped the tech guys at Powermaster an email mentioning the heat shield and they told me "do not add any heat shield to their starter as this would cause heat soak" and my problem was most likely caused by a fault in the ignition not sending 12 volts to the starter. I have tested the ignition lead while removed from the starter and it registered 12V, then tested it while connected and got 6V, so there does seem to be some electrical issue affecting them rather than the heat from my headers.

[msgdsrf]

Curious what you find out to fix the issue.

[Matthewg321]

Not to be a downer, but I believe that the conductivity of the metal parts themselves are going to transfer more heat than the shield will protect the starter from.

Could you post a video or a link to audio of your "slow cranking"? I feel that that may be the cause of my '71's slow starts.

[eightbanger]

Sorry mathewg321, I hadn't taken any video or audio at the time the previous starter was beginning to fail...wish I had now, would have been good for reference. Suffice to say that it acted exactly as a dead or dieing battery would, the only difference being that it would crank progressively slower after longer drives, ie the hotter everything would get inside the starter, so much so I had to leave the truck running while filling up with gas, otherwise it would barely turn over so i'd have to wait until it cooled and then it would crank just enough to fire the engine.

[geezer#99]

Do you gentlemen know about installing a remote solenoid?
It cured a hot start for me after I did all the obvious stuff like new starter, cleaned all the connections, tried a heat shield, new wiring from the ignition switch, better battery etc. Bunch of money spent for a 20 dollar solenoid kit.
http://67-72chevytrucks.com/vboard/s...d.php?t=475748
Available from summit too!
http://www.summitracing.com/parts/tff-7629

[eightbanger]

Thanks Geezer, read the entire thread, man there is a lot of for and against in there, and if I'm honest I will say that I'm not yet convinced the added solenoid is the fix. The guys at Powermaster have assured me that the reason for my first starter from them failing is a wiring issue, but if it were, why isn't the wiring issue causing it to fail immediately when the new starter is fitted (it works perfectly) and worked perfectly for 2 mths, and why did it take 4 yrs to happen on my old starter?

[volksworld]

the remote solenoid is to fix a no-crank condition due to a voltage drop through the key circuit....not the problem you're having...slow cranking would be insufficient amps through the battery cables themselves...rather than new "chain store" cables I had a truck parts shop make up much heavier gauge cables...ran the negative to the block,new ground strap to chassis,ground connections to bare metal etc...just cause it looks clean doesn't mean its a good connection...obviously a battery with like 850 cca (interstate megatron plus)...load test yours,maybe you have a dead cell...too much initial timing or too high a compression ratio or not enough octane will also fight the starter on hot re-starts

[volksworld]

p.s. I also run the ford solenoid...I've been fitting them onto VW's for 30 + years, so when my truck did the no-crank 20 yrs ago it was the natural solution...I do notattach the battery cable to it,no reason to split that and give 2 more points of resistance in the circuit...I wire it just in the key circuit(sorry,too stupid to know how to post pic's or diagrams) new 10 gauge wire from battery to left terminal,new 10 ga wire from right terminal to small starter connector,original starter wire to small left front terminal on ford solenoid to trigger it....this is to get more voltage into the starter solenoid to get it to engage if it does nothing at all ,but wont affect cranking speed

[geezer#99]

BUt you know he does say that after a long drive he has little or no cranking until it cools down. Heat soak doesn't need to be a total no click, no crank situation. Slow cranking is also caused by heat soak.
Too much initial timing or high compression can be eliminated with the addition of an interupter switch on the power wire to the dizzy. Turn the switch off, get her spinning then flip the switch and she'll fire.
And an easy check next time it won't crank is to unplug the wire at the dizzy and see if it helps crank it over.
I agree with checking the cables. THey rot on the inside too.

[VetteVet]

Here's my opinion for what it's worth.
The sole purpose of the remote solenoid is to eliminate the voltage drop that exists on the purple wire. When the engine is hot the solenoid will not engage due to the heat soak on it's windings. The remote solenoid will provide a full 12 volts to the solenoid and overcome the resistance the heat soak presents.

If the solenoid is engaging but the starter is turning slowly then the starter windings are heat soaked and you need more voltage and current in the windings to turn the engine.
To test this, the next time you have this problem try jumping from the solenoid terminal directly to the positive battery cable on the starter. This is exactly what the remote solenoid does to provide the most voltage and current to the solenoid. I would guess that the starter will still turn slowly and the solenoid will engage just as it does now.

With headers you may have some trouble getting to the terminals and you must make sure the truck is in park and the e-brake is on because the truck will possibly start in gear.
Have you considered header wrap. It's supposed to reduce the heat considerably.
Make sure all the cable connections are clean and tight and that you have a good solid ground to the engine and frame.

[msgdsrf]

Vette makes a good point. Personally I'd try the heat wrap you already have, it's worked for a lot of folks.

[VetteVet]

Originally Posted by msgdsrf

Vette makes a good point. Personally I'd try the heat wrap you already have, it's worked for a lot of folks.

I think so too and Geezer has a great idea about the kill switch for the dizzy. he said about the same thing I did but he beat me too the punch on the post.

I'm a little suprised that the mini starter has heat soak. I've always heard that they were the cure for that.

[geezer#99]

If you look at his pic of the old beside the new, you'll see the new one has the solenoid cocked closer to the exhaust (away from the block). Could be why it expired early.

[eightbanger]

Originally Posted by msgdsrf

Vette makes a good point. Personally I'd try the heat wrap you already have, it's worked for a lot of folks.

And it was recommended by the store who sold me the new starter, but then the guy from Powermaster tells me, do not use any heat shield on their product as this will not let the heat escape and cause true heat soak...his words. Then a quick look at the FAQ on their website...."Question" should I use a heat shield? and it states that they are not necessary, but fine to do so....he's not yet clarified that little conflict.


I'm a little suprised that the mini starter has heat soak. I've always heard that they were the cure for that.[/QUOTE]

I had heard this too!

Originally Posted by geezer#99

If you look at his pic of the old beside the new, you'll see the new one has the solenoid cocked closer to the exhaust (away from the block). Could be why it expired early.

Again I did that on advice from the store when they refunded me and gave me the replacement. But then why did the cheaper Ebay one last 4 yrs? which in itself isn't much to write home about...but it's way better than 2 mths for the Powermaster.

I can't figure out if this is an electrical issue or heat soak from the manifold, and if it was the heat soak then either I was unlucky and bought a faulty starter, or Powermaster are extremely susceptible to heat.

[volksworld]

just another thought...I don't have this issue cause with the stick i'm using the cast iron bellhousing and the starter nosecone bolts to it...but...with a starter that bolts to the block,and also uses an aftermarket aluminum adapter,maybe there isn't enough clearance between the starter gear and the flexplate....which would tighten up even more as things heated up...so you might need to shim between the starter and block