ohiovet

Dennis,
Remember that all of the electrical items on your Corvette depend on a good ground system.
So if a ground strap is suppose to help eliminate radio noise it is also helping with the overall grounding system.
You can not have to good a ground in a Corvette.
Bruce B

jusplainwacky

Yes, grounding is very important, but what is equally important is understanding what the issue is (in this case radio static) and effectively addressing that issue.

I can honestly say, I don't think Chevrolet had a clue what/how to solve this problem and just started grounding everything. What they problem should have done is looked at it from a "shielding" perspective and not a grounding issue...and looking at the radio itself in how to shield the AM (amplified modulated) signal from engine noise (spikes). As was mentioned earlier...it's not so important that the frame be grounded as there isn't much connected up to it, and it's certainly not a "shield". As long as I get a decent ground to the frame from the engine, I should be good to go. However it should be noted that a good frame ground is needed to prevent static build up, specifically when your gas tank is connected directly to the frame.

jusplainwacky

Anyone have a picture (dimensions) of the washer that goes on motor mount? If mine is wrong, then now would be the time to replace it.

JohnZ

Looks like this.

jusplainwacky

Hey John...thanks for the picture. It's hard for me to see, but is it thick, or is there some type of fiber washer under it?

jusplainwacky

Jim thought it looked like a crankshaft balancer washer...what ever the heck that is.

JohnZ

Nope - just an ordinary flat washer; don't recall the dimensions - don't have a C1 to measure.

Frankie the Fink

As requested; there are some for sale on eBay right now:

jusplainwacky

Ok...I didn't know if it was some special looking thick washer or just an ordinary washer.

jusplainwacky

Frank...thanks for the picture, how weird looking!

DZVette

Dennis
Here's one from my '60 minus the ground strap which I still need to put back.

It measures about 1 3/8" diameter and about 5/32" thick. The bolt kit was purchased from Paragon a while back.

Dave Z

jusplainwacky

Ok...that looks like a plain old washer as you said.

jusplainwacky

I took of my bolts and I notice on the passenger side the hole is much bigger than the bolt going though it. Is this "normal"?

jim lockwood

Perfectly normal. That large hole was how the factory allowed for manufacturing tolerances in the locations of the mounts on the frame.

ohiovet

Correct,
Put in the drivers side bolt first.

jusplainwacky

I guess I need a thicker washer, cause when I was tightening it up, the washer started to distort down the hole.

rich5962

Yes the fuel tank does get "mechanically" connected to the frame on your '58 via the fuel line to sender rigid fitting. When the frame line gets attached with clips to the horizontal frame rails it adds more ground points.

However, it should be noted that the later '61/'62 sender uses a rubber hose to connect the frame fuel line to the tank fuel gauge sender and must rely on the harness ground wire to complete the ground circuit.

The front and rear tank hold-down strap mounts get attached to isolated reinforcements, front and rear, riveted to the fiberglass body. Without the harness black ground wire(from the rear harness to the dash harness grounds) attached to the tank sending unit, the tank ground is isolated and floats.

That's why on those it's a good idea to add a ground from the tank sender mount screws, directly to the chassis, most commonly to the horizontal frame rail fuel line clip mount screw. Best to use a toothed washer there for that. It should be noted that adding a ground to the soft top brackets doesn't help, as those are ground isolated also. Even with the soft top latched to the windshield, there is no "direct" connection to chassis ground to those brackets. I did some experiments a while ago on my last body-off of a '60 to prove that.

Also, on the '58 to '60, there exists another sometimes forgotten ground wire. At the left rear bumper inner bracket, there's a threaded hole in the horizontal bumper bracket for the harness ground. You can barely see it under the spare tire/trunk latch fiberglass filler. It a Black wire with White tracer. BTW, this also assists with a ground reference for the tank sender as all grounds tie together in the harness.

Quite often, rust and corrosion opens up this connection making the rear lights problematic. If this happens, one has to remove the left rear bumper, then remove the horizontal bracket to then drill out the rusty screw and rethread it. Sometimes easier to just drill a new hole and thread for the screw. IIRC, it's a #8-32 screw with a toothed washer.

Rich

jusplainwacky

Hey Rich....thanks for all this information. Greatly appreciated!

jusplainwacky

I changed out the washer to a thicker one...no problem now. (see pic below)

I was going to put on the exhaust ones, but I can't figure out how they go on and I couldn't find any pictures in my assembly manual or on the forum. One end of the braided ground has a much bigger bolt hole than the other and I have nothing (that I can see) where the small bolt hole would connect to. Anyone have a picture?

DZVette

Dennis

Here's a page from '60- AIM and a shot of the exhaust GS on the psgr side.

Dave Z