70 BB starter

[andrew strauss]

Last week I reported in thread that I had repaired my grinding starter/no start when hot.Today after I let it idle for a while in the driveway and then turned it off the problem reoccured.I replaced the ground wire from the block to the frame last week and this temporarily fixed the problem.When you do manage to get it started it runs differently,so I checked the timing.it was off.I have hei wich grounds threw the block to the frame.I suspect the bad ground would be causing this as well.Am i correct?The bigger question is why is my car eating ground cables?After replaing the ground cable last week the starter sounded amazingly quite and the car actually seemed to run better.Am I crazy?What is a permanent repair?I dont mind if it wont pass judging.

Thanks

[tom444634]

Re: 70 BB starter

Andrew,

I have a 71 BB and it still has the original starter. When I first got the car, it suffered from "big block syndrome" as we used to call it. On this car it was an easy fix, I set the timing correctly and put a new battery in it and it has been fine ever since. On the other hand I had a 71 SS-454 Chevelle that was a real bear to get started when it was hot even after a complete restoration. Go figure.......

For what it is worh, here are some things I have tried with varying success over the years to correct this problem. I remember seeing your previous posts, so please ignore if some of these are repeats.

1. Make sure the battery and cables are in tip top shape. If you run a side post battery (not sure if side or top for 70), take the terminals off and make sure there is no corrosion on the mating surfaces. Then re-install them and make sure they are real tight. Is there a battery disconnect switch in line somewhere? This may cause some problems if it is corroded.

2. You had some success with replacing the ground before, so that is pointing you in a direction that says ground may be an issue. First check the battery cable ground to the frame. Remove it from the frame and clean the mating surfaces. Re-install it using the correct star washer, this will bite into the metal surfaces creating a very good ground contact. The star washer should go between the frame and the connector as shown in the AIM.

3. Keeping with the ground theme, verify that the cable you used to ground the frame to the block is the correct gauge (2 ga? I can't remember)and is attached as shown in the assembly manual with the star washer between the frame and the cable connector. Clean the mating surfaces prior to installing the cable. In the assembly manual for my 71, the cable is shown going from the frame side of the engine mount to the top of the starter support bracket (you do have the bracket installed I hope).

4. Make sure that the starter has the heat shield around the solenoid installed.

5. There is a black ground wire coming out of the wire harness that goes to the solenoid. Make sure that this wire is grounded to the starter mounting bolt as the assembly manual shows. (Again I'm referring to my 71 manual. I don't know if 70 is different)

6. Verify that the timing is set correctly. (I believe you have already done this)

7. Don't forget about the positive cable either, make sure its' connection at the starter is clean and secure. Check the crimp from the lug to the cable for any corrosion or being loose.

I'm sure I may have covered things you have already done, but maybe not.

I'm also assuming that the starter is the correct "hi-torque" starter used for the big block applications and that you are not running real high compression, heavy valve springs or headers.

Hope this helps,

Tom

[Joe L.]

Re: 70 BB starter

Andrew-----

As I mentioned previously, I was very skeptical that the replacement of the ground cable was going to be a solution to this problem. Since the problem seems to be somewhat "intermittent", I think what happened was after you replaced the cable, the problem coincidentally went "dormant". In other words, I don't think that replacement of the ground cable had any effect, one way or the other, on your problem.

Second, there is absolutely no way that your car could have any "condition" causing it to "eat" ground cables. For all intents and purposes, ground cables are a "solid state device".

As I understand from your previous reports, you've now replaced the battery positive cable, the battery negative cable, and the engine-to-frame ground cable. Is that the case?

[andrew strauss]

Re: 70 BB starter

All cables have been replaced .The positive and negative from the battery to the frame are new repros made by Lectric ltd.They appear to be high quality.The ground wire from the block to the frame is a wire I bought at the local auto supply store and is solid copper 2 gauge.As soon as I replaced this wire last weekend the starter no longer had a grinding noise,theengine spun over as a normal one should and the car actually seemed to run smoother.It ran like this all week.I could heat soak it and it would fire right up.Today I started it and it ran fine.turned it off and the problem reappeared.When I did get it started it didnt seem to be running the same,so i checked the timing and it was way off.In fact to get it to the mark I had to realy move the dist further than I have ever move a the dist.This is why I think I have a ground problem.

[Chas C Henderson]

Re: 70 BB starter

This might seem silly, but I have to ask, are you sure you tightened the distributor clamp down enought to keep the distributor from moving? Seems odd that it would be that far off for no good reason.

Chasman

[andrew strauss]

Re: 70 BB starter

It is very tight.What is driving me crazy is the fact that last week it was gone after I replaced that ground wire.I am at the point at wich I have checked everything twice.When it is right the starter sound like a normal starter hot or cold.When it is wrong you can hear the starter 3 house down and you have a very difficult if not impossible time getting it to start when hot.At this point the car is just a very expensive conversation piece