bmillerw

ooo

Bluestripe67

Have you tested your battery, checked all connections for ANY corrosion. Dennis

BADBIRDCAGE

In addition to Dennis’s recommendations check your timing also. If too far advanced it can be difficult to start when hot. Or it could be heat soak on the starter.

Bluestripe67

Aaah! I missed those, good ones! Dennis

Dan Hampton

Don't rule out a possible heat soak issue with your starter. "Rebuilt" can mean a thousand things. If I have a generator/alternator/starter issue, I always take it to a reputable electrical repair shop and have them do a complete analysis. It beats the randomness of securing a good unit from a parts house.

Dennisscars

I'll also add to do a load test on the battery during this condition. A marginal battery doesn't help.. I'm finding batteries don't seem to last very long any more.

I bought a battery load tester from harbor freight and test at every service now..

2009stanger

I had a similar problem. It was the starter going through heat soak. I put a heat wrap on it and it helped.

2009stanger

It’s been awhile, but I believe I got mine from Amazon and cut it down to fit. Check out part number x-1701 from zip corvette. That’s similar to what I have.

Powershift

As pointed out, there are a number of things that might be causing or contributing to your problem.........so check them out.

I had the same problem with my 1967 327/350 HP car (L-79) and finally had my starter rebuilt with additional field coils inside the case to be more like a big block starter. It can be done by someone who knows starters and how to repair them. This adds a lot more torque to the starter under all conditions. Now my starter will spin the engine smoothly even if it is 110 F in the shade. Something to consider.

However, doing this will change the sound of the starter a bit. I sort of miss the old slower "Corvette starter" sound, but no longer have fear of hot restarts. My 11 to 1 compression engine now sounds more like the whine of a jet engine when I energize the starter.....or maybe like I have two 12 volt batteries working in series (24 volts)

Larry

mxw1

I've had Chevy v-8s for 40-50 years, very common problem. I've had one car for about 30 years and the replacement starters work fine for several months and then start to turn slow when hot. I must change the starter in that car every year. Can't stop to get gas after getting off the freeway during commute.
People say that the heat expands the armature and it drags on the case windings, especially when the bushings get worn, I could see that.
I think I fixed it the last time I had it out about two months ago. I never thought about it before, but if it is metal expanding, it expands in all directions, including length.
I removed one fiber shim from the back of the starter; increased the end play of the shaft. Like I said, the starter has been working fine since then.
you might want to try that...
Good Luck.

Mike

AZDoug

Check and clean your engine to frame ground,and battery cable ground very carefully. Paint under the ground cable can cause issues, as well as corrosion between the cable and the cable. Not to mention battery terminal to cable connection. Had this problem with teh '72 when i first got it. Started great cold, slow, slow cranking when hot, almost like it didn't want to even turn over.
Put it on the lift, removed the starter bolts one at a time, cleaned and de-greased them, and cleaned under the battery cable connection, and cleaned the cable end with steel wool, and decreased that connection bolt also..
Problem solved.

Its cheaper than running out and getting another starter.

Doug

AZDoug

I always use high torque (longer) starter on anything that I don't care about originality. You can tell a high Tq starter because it has a 1" copper spacer between the power tab on top of the starter , and the solenoid connection. You can always swap starter noses if you can't find a high tq starter with your nose bolt mounting pattern.

Doug

karkrafter

I have put cheap e-bay mini starters in all my muscle cars, HUGE difference when hot, Not sue if it's gear reduction thing, or a more HP thing or the fact it's smaller and further away from the exhaust thing...maybe all three.

Bluestripe67

We appreciate you letting us know it fixed. Dennis

BADBIRDCAGE

actually timing by ear isn’t a bad thing if you don’t have a light handy. Warm engine up, dial distributor to max fast idle, lock down. Just remember that if it’s difficult to start when hot back it down a touch.

Used to run 22 degrees initial advance on a 69 Dodge 340 with dual point distributor. Once in a while it would be touchy on hot start. But that was a mechanical advance, not vacuum.

BADBIRDCAGE

timing by ear is a temporary solution. Need to get that light on it for true accuracy and best performance. The way we determined 22 initial advance was best was by using a light.