Upadte:70 BB starter

[andrew strauss]

Today I have spent the better part of the day in the garage attempting to repair my hot start problem.As I stated in earlier post with as little as 20minutes idling time the starter makes an awful grinding noise and from time to time disengages the flexplate.It will engage spin the engine approx 1/4 revolution and then it is as if the engine locks up and the starter gear is kicked back into the housing.I have good voltage at the starter and solenoid.The starter is delco # 323-255[correct for car]with new solenoid.the cabels are new as is the harness.Just for grins I swapped the battery from my wifes car.I even played with numerous different shim combos.Nothing even affects the problem.I also checked the timing.When the engine is hot I can spin it over with a ratchet[it is hard but can be done].What am I missing?The car can sit for a month without being started and crank right up,but let it idle for 20minutes and you will need aletter from god to get it to start.

[Joe L.]

Re: Upadte:70 BB starter

andrew-----

So, the car is an LS-5 with THM-400?

[andrew strauss]

Re: Upadte:70 BB starter

Yes

[Joe L.]

Re: Upadte:70 BB starter

andrew-----

Does the starter have an ALUMINUM nose utilizing 2 "long" starter bolts for retention to the block?

[andrew strauss]

Re: Upadte:70 BB starter

Yes it does and the bolts are the correct gnurled type

[andrew strauss]

Re: Upadte:70 BB starter

Let me add another detail.When this was happening this afternoon i removed the starter,disassmbled the starter for inspeftion and then reinstalled it only to have the same problem.At thhis point the starter was only warm to the touch.The car had cooled to the point that i could comfortably touch the exhaust and the starter.What is the possibilty the the engine has something internally wrong that causes excessive cranking power when hot.

[Joe L.]

Re: Upadte:70 BB starter

andrew-----

From what you described, I don't think that you have a "hot soak" problem, at all. If you still have the problem when the engine has cooled to the point you described, that's NOT TYPICAL, at all, of the problem I'm talking about.

So, I don't really know what your problem is. However, I really doubt that it has anything to do with an internal engine problem which results in the need for additional cranking power when hot.

[Mark #28455]

Re: Upadte:70 BB starter

Try cranking the hot engine with the ignition disconnected (so you get no spark). If it turns over fine, then it's likely either too much advance at idle or the starter is weak. What is the timing set to? Did you set it at idle or by revving the engine to max timing? Is the timing returning to baseline at idle?

Mark

[andrew strauss]

Re: Upadte:70 BB starter

Good point .I did disconnect the wires to the dist and it was better.I did set base timing at idle to 8.I am starting to think that maybe with the timing being off and all the abuse I have put the starter threw if I didnt dmage the starter.I did take it out and apart and found nothing.

[Clem Z.]

make sure the battery cables are

pure copper not copper plated aluminum. you can tell by the weight.

[Clem Z.]

PS get a clamp on amp meter and check the current

draw hot vs cold engine. this will tell you if there is excess torque required to turn over the hot engine

[Andrew Strauss]

Re: make sure the battery cables are

I have been wondering about the cabels.They are new but that doesnt mean much these days.I do have an amp meter and will try that angle.

[Jack H.]

Be careful!

Measuring starter motor current can be tricky. You'll want a professional grade, induction, ammeter. This is the kind that clamps around the wire carrying the current vs. the ordinary style ammeter that connects in series to the load.

Most 'hobby' grade VOM meters are designed for measuring LOW power situations (typically, less than 10A of DC current) and you can easily 'blow' one of these meters trying to measure the current profile of a starter motor...