Anyone seen this syptom?
Thread Starter
Instructor
Joined: Nov 1999
Posts: 155
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From: Eureka NV
Anyone seen this syptom?
My 79 won't start when it is hot!! Drive a hundred miles, shut it off, and no start. Let it cool down and I'm back to driving.
I have eliminated the starter and solenoid. I can jump the solenoid wire at the harness plug and it starts just fine even when hot. I am suspecting the nuetral safety switch now. Where is it located? In the console I suspect.
Ken
I have eliminated the starter and solenoid. I can jump the solenoid wire at the harness plug and it starts just fine even when hot. I am suspecting the nuetral safety switch now. Where is it located? In the console I suspect.
Ken
Melting Slicks
Joined: May 2002
Posts: 2,508
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From: Wisconsin
Usually the cause for this is starter heat soak. Adding a heat shield on the starter will fix it. I don't see how the neutral safety switch could cause it as it is in the console. It's on the side of the shifter. It just doesn't make sense for it to fail while hot as the heat doesn't get to it.
Race Director
Joined: Mar 2001
Posts: 11,322
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From: Living in the Hartland
On a 4 speed the switch is up on the clutch pedal bracket, but like schmucker said I doubt it would be heat affected, you might check all your elec connections when corroded they do not conduct very well when hot.
Race Director
Joined: Dec 1999
Posts: 19,610
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From: Forked River NJ
Very common problem with small block chevys. It is heat soak. Either wrap the starter in a shield or get a mini starter. I fought this on many cars and finally went to a mini starter. Never had a problem again. There is no heat on the clutch switch since it is inside the car. Never had one go bad from heat. They do break but it will happen hot or cold. Check all the wiring also, if it is old and brittle you are not getting good contact. I'll bet it is the starter though.
There is someone selling a mini starter on the C3 parts for sale section. Looks like a good deal. If I needed one I would buy it.
There is someone selling a mini starter on the C3 parts for sale section. Looks like a good deal. If I needed one I would buy it.
Last edited by Gordonm; Aug 18, 2004 at 02:36 PM.
Le Mans Master
Joined: Mar 2004
Posts: 7,503
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From: Little Rock AR
There is too much resistance in the starter circuit. If you can start it by jumping the solenoid so the fix is to find the resistance and repair it (harder) or add the Ford starter solenoid (easier).
Re-attach the purple "start" wire from the GM starter to the "S" terminal on the Ford solenoid. Run a similar (12 gauge stranded copper) wire from one of the fat Ford terminals to the fat terminal on the starter where the battery cable attaches. Run a wire from the other fat terminal on the Ford solenoid to the "S" terminal on the starter and be sure to ground the Ford solenoid.
This is cheap and effective old school repair for a common problem. You can bypass all the resistance in the starter circuit and it makes a great place to hook up a remote starting switch when servicing the engine too.
When you hit the key, the Ford piece energizes easily even with low voltage (unlike the GM solenoid) and sends a full battery voltage to the starter, and it starts just like it did when you jumped the solenoid.
-Mark.
Re-attach the purple "start" wire from the GM starter to the "S" terminal on the Ford solenoid. Run a similar (12 gauge stranded copper) wire from one of the fat Ford terminals to the fat terminal on the starter where the battery cable attaches. Run a wire from the other fat terminal on the Ford solenoid to the "S" terminal on the starter and be sure to ground the Ford solenoid.
This is cheap and effective old school repair for a common problem. You can bypass all the resistance in the starter circuit and it makes a great place to hook up a remote starting switch when servicing the engine too.
When you hit the key, the Ford piece energizes easily even with low voltage (unlike the GM solenoid) and sends a full battery voltage to the starter, and it starts just like it did when you jumped the solenoid.
-Mark.
Thread Starter
Instructor
Joined: Nov 1999
Posts: 155
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From: Eureka NV
I think stingr69 has it right. Too much resistance is something an old electronics guy can get a grip on!!
I am going to try the Ford solenoid..... Beats the heck out of $85 dollars for a nuetral safety switch.
Thanks to all for thier suggestions!
NOW... where the heck can I hide that FORD part so Corvette zealots won't see it?? hmmmmmmm................
Thanks again,
Ken
I am going to try the Ford solenoid..... Beats the heck out of $85 dollars for a nuetral safety switch.
Thanks to all for thier suggestions!
NOW... where the heck can I hide that FORD part so Corvette zealots won't see it?? hmmmmmmm................
Thanks again,
Ken
Race Director
Joined: Dec 1999
Posts: 19,610
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From: Forked River NJ
The problem is the GM selonoid. It won't energize with lower voltage. The resistance is in the selonoid. A new selonoid will help the problem but it won't go away totally. I've tried it.
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Race Director
Joined: Mar 1999
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From: Calif.
You don't need mini-starters. You don't need heat wrap. You need to go down to the local Chevrolet or GMC dealer and buy a new, shorter starter solenoid spring. It will cost you less then $10 and about a half-hour of your time.
The part number you want is Delco Remy 1958679.
This mod will eliminate the hot start problem 99.9 percent of the time. You're welcome.
The part number you want is Delco Remy 1958679.
This mod will eliminate the hot start problem 99.9 percent of the time. You're welcome.
I did the new solenoid and shorter spring 2 years ago and haven't had a problem since. And I live in south Texas, where it's a starter torture test every day!!!
Team Owner
Joined: Sep 2003
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From: eville in
Originally Posted by The Dude
You don't need mini-starters. You don't need heat wrap. You need to go down to the local Chevrolet or GMC dealer and buy a new, shorter starter solenoid spring. It will cost you less then $10 and about a half-hour of your time.
The part number you want is Delco Remy 1958679.
This mod will eliminate the hot start problem 99.9 percent of the time. You're welcome.
The part number you want is Delco Remy 1958679.
This mod will eliminate the hot start problem 99.9 percent of the time. You're welcome.
didn't know that one 
Drifting
Joined: Nov 2002
Posts: 1,665
Likes: 1
From: Ontario
Originally Posted by Gordonm
The problem is the GM selonoid. It won't energize with lower voltage...
Sometimes guys put a starter kill relay or kill switch in series with this line which adds resistance and causes a voltage drop as well.
Le Mans Master
Joined: Mar 2004
Posts: 7,503
Likes: 1,511
From: Little Rock AR
There was an old GM TSB that said you could cut off 1.5 coils from the original solenoid spring and that would work in a pinch but that assumes you do not have headers or other heat producing mods that aggravate the problem even more. It was a problem way back when that we are still dealing with today.
-Mark.
-Mark.
Instructor
Joined: Jul 2004
Posts: 210
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From: Missouri
Hmmm sounds like heat soaked at first but when he said it starts fine HOT by jumping the solenoid it stops making sense. I'm thinking loose connection or weak connection when the key is turned to the start position.
Instructor
Joined: Jul 2004
Posts: 210
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From: Missouri
Also about starters and hard starting when hot. The armature has segments on the commentator and this commentator is held on by hairpins. These are soldered in and when ran with a low/weak/bad battery it will spit that solder out. If you ever take the back plate off a starter or for that fact a generator (not an alternator) and see a ring of solder around the case you'll know it end of story for that armature.
With a little solder there it will start fine cold but after it heats up the little solder left isn't enough to give a good solid connection and it turns SLOW. There are special armatures you can buy (lil expensive) that have wielded commentators. I personally don't use them on anything as I think they are a waste of money.
With a little solder there it will start fine cold but after it heats up the little solder left isn't enough to give a good solid connection and it turns SLOW. There are special armatures you can buy (lil expensive) that have wielded commentators. I personally don't use them on anything as I think they are a waste of money.
