68 Hot start issue
Thread Starter
Heel & Toe
Joined: Jun 2006
Posts: 24
Likes: 3
From: Ulster PA
68 Hot start issue
My 68 maybe having a heat soak issue but before I spend time installing a Ford solenoid or $$ on a mini starter I would like some of your input. Here is what is happening. After driving and shutting down for short time it will not turn over. When I turn the key to start I will hear click noise and the amp gauge drops to -40. I have searched through the post but I have not found any reference to the amps dropping to -40. Any help would be appreciated. No issue on a cold engine and I am not running headers.
Le Mans Master
Joined: Aug 2010
Posts: 9,272
Likes: 17
AC Delco part #U939, chevy installed them for a few years, put one on my 76 before issues started, works great, let me find a link
http://www.google.com/url?sa=t&rct=j...GrYTZ92AKNsFow
http://www.google.com/url?sa=t&rct=j...GrYTZ92AKNsFow
CF Community Team
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It could be a ground issue. Check you battery connections, starter connections and the ground underneath the battery to the frame. It could even be a weak battery. I went through all of that with my 68 with a similar hot start issue. Mine was the starter solenoid. No heat shield from the factory on my early 68 big block. It starts fine without it.
Safety Car
Joined: Sep 2011
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From: Madeira Beach, FL
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I had same issue to the tee.
DB Electric mini torque starter.
Solved the problem.
I was in a 92* July 4th parade w/ her.
Shut her off after parade and restarts were no problem.
We drove under 2 miles in an hour n a half in 90* weather with
a big block. If the mini was gonna fail this was the day to do it.
No problems!!!!
Check on this forum for mini torque starter from DB Electrical.
You won't have to revisit thie problem again.
They are cheap in price, I was suprised how well it works for the $.
Marshal
DB Electric mini torque starter.
Solved the problem.
I was in a 92* July 4th parade w/ her.
Shut her off after parade and restarts were no problem.
We drove under 2 miles in an hour n a half in 90* weather with
a big block. If the mini was gonna fail this was the day to do it.
No problems!!!!
Check on this forum for mini torque starter from DB Electrical.
You won't have to revisit thie problem again.
They are cheap in price, I was suprised how well it works for the $.
Marshal
Burning Brakes
Joined: Sep 2005
Posts: 1,050
Likes: 205
From: Lewes Delaware
I also had the same issue on my 73, including the -40 reading on the amp meter. Cleaned and tightened all grounds, rebuilt starter with heavy duty solenoid. Also reversed the R and S wires as they were installed wrong by the shop that re-installed my starter the previous time. Work great now.
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Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
The other "starter" heat soak issue I believe is a myth and is actually a poor grounding issue.
Thread Starter
Heel & Toe
Joined: Jun 2006
Posts: 24
Likes: 3
From: Ulster PA
Based on input from this forum checking out the grounding circuit will be a good place to start. Good job for tomorrow. Thanks all for the help in trying to resolve this issue. I will post back results again thank you.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
the ground under the battery to the frame or rear is probably the real problem...before cobbling the issue up with mini anything, Ford switches, or whatever, clean all the grounds.....BTW, OE parts work the best until the back alley engineers suggest modifying the start system....they seem to know more than those who designed and built them......as suggested above at least once, a strong stock style battery is also a good investment rather than off brand mini starters
Le Mans Master
Joined: Aug 2010
Posts: 9,272
Likes: 17
sure glad I suggested an actual GM part actually installed by GM engineers in a GM plant and not any of those back alley folks that believe in those myths.
but on a serious note, these folks are correct, I like to use the GM U939 for things like bumping the engine for testing and accessories that folks usually run to the back of the alternator or down to the starter, easier to reach, saves burning my hand on a hot manifold trying to bump the starter, with these batteries behind the seat, makes a good spot to get or give a jump if needed. hope this helps
btw, you can hook them up a couple of different ways, depending on your future plans, not good if you're restoring, but for aftermarket 'stuff' works fine.
but on a serious note, these folks are correct, I like to use the GM U939 for things like bumping the engine for testing and accessories that folks usually run to the back of the alternator or down to the starter, easier to reach, saves burning my hand on a hot manifold trying to bump the starter, with these batteries behind the seat, makes a good spot to get or give a jump if needed. hope this helps
btw, you can hook them up a couple of different ways, depending on your future plans, not good if you're restoring, but for aftermarket 'stuff' works fine.
Last edited by oldalaskaman; Jul 25, 2012 at 10:21 AM.
Thread Starter
Heel & Toe
Joined: Jun 2006
Posts: 24
Likes: 3
From: Ulster PA
OK, here is where I am at. I checked all the wiring connection's and all looked good except for the notorious battery ground to frame. Cleaned frame area, ground cable and bolt. Now to take it for a test drive. Will report back good or bad results. Again thanks to all for the helpful feed back
Racer
Joined: Oct 2009
Posts: 280
Likes: 1
From: cleveland Ohio
dont forget the ground wire that comes off the starter and bolts to the bell housing,,mine looked fine,but upon closer inspection,it was frayed inside the rubber coating,at the connection where it bolts to the bell housing.i cliped it there,put on a new connector,,all is good now. you gotta really look close at these wires,,at first glance they look ok,but..
Safety Car
Joined: Sep 2007
Posts: 4,458
Likes: 331
From: Indy Indiana
your battery will degrade 10% a year. if you just have a cheap or a medium battery that is 4 years old, it will no longer output the amps needed to crank over a hot engine with a hot starter. yes heat soak is an issue, and yes you must have really good connections to pass all those amps.
a hot engine and a hot starter needs more amps to crank. I have had this problem several times thruout the decades on big engine Vettes and GTOs. I never replaced a starter or a solenoid. my solution was to buy the biggest baddest cold cranking amp battery you can find. get you a 8 year 1000 amp battery. autozone or wally world have them.
my battery is 4+ years old and my engine is starting to crank slow when hot. Time for another new one. I know it will solve my problem.
adding to the problem are the cheap foreign batterys that go bad long before they are supposed to.
a hot engine and a hot starter needs more amps to crank. I have had this problem several times thruout the decades on big engine Vettes and GTOs. I never replaced a starter or a solenoid. my solution was to buy the biggest baddest cold cranking amp battery you can find. get you a 8 year 1000 amp battery. autozone or wally world have them.
my battery is 4+ years old and my engine is starting to crank slow when hot. Time for another new one. I know it will solve my problem.
adding to the problem are the cheap foreign batterys that go bad long before they are supposed to.
Thread Starter
Heel & Toe
Joined: Jun 2006
Posts: 24
Likes: 3
From: Ulster PA
I took it out for a short run only about 6 miles after getting back home I let her sit for 10 - 15min. It restarted just fine, however, I need to take it for a good run and test it again.
