Grounding the engine

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grassy

grassy

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Funny, I was just reading 2 posts that were about keeping your parts well organized when you take them off the car and a grounding issue re gas gauge and I just remembered a quiestion that I have..

If i understand correctly, you are supposed to ground the engine to the frame and you have a ground wire that comes off the neg battery terminal that grounds to the frame as well.

For the life of me and two major clean ups of the garage I cannot find my ground start that goes from engine to frame..It looks like a quilted, flat strap.

What would happen if I took 2 cables off the neg battery terminal and grounded them to the block and frame ? That would be equivalent ?

Thanks
ian.
 
Typically there are three grounds. Battery to core support, battery to drivers side head and the strap from the rear of the passenger head to firewall.

I think I would opt to find the braided cable you had or buy a short ground strap and run it to the firewall like it was. You are essentially grounding the engine to the body which I assume helps with all of the body grounds.
 
Man, what a quick response !

Bad,

is "Battery to core support" battery to body ?

to head do you mean the holes that we attached the chain to lift it ?

Thanks
Ian.
 
Core support is where you radiator etc is bolted up. In the front of the head there is a hole for a bolt, that's where most are hooked up.
 

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grassy said:
Man, what a quick response !

Bad,

is "Battery to core support" battery to body ?

to head do you mean the holes that we attached the chain to lift it ?

Thanks
Ian.
Click to expand...

Badsport appears to have gone off-line,

oops.. maybe not

, so yes "core support" = radiator support..

and "head holes' refer to the bolt holes in the front of the head,, sometimes supporting P/steering etc..
 
those old flat quilted ground straps suck, be sure to replace with a new cable like the one in the pic above.
 
This is how I grounded every vehicle I owned. I buy a bunch of what ever gauge cable, for normal use 4 Gauge is fine. I use one of these crimping tools in addition to a small torch and solder. Cover everything with shrink tube. I used what ever lugs are needed, chose from these . I use these for connection to the battery. I go from the battery to the frame, from the frame to block. I also go from the battery to the radiator support with a piece of 10 gauge or so. And from BOTH cylinder heads, assuming it is a "v" engine, 10 gauge here as well. And if it is a vehicle with body bushings I will run a piece of 10 gauge in at least one sot from the frame to the body tub. Overkill? Some will say it is. I have done more than one EFI swap where stuff runs on 5 volts or less. Often stuff is in milliamps. So if your grounds are not up to snuff YOU WILL have troubles. Any and all connections get wire wheeled/dielectric greased as well. I try to use external tooth star washers every where as well.
 
Gotcha. This is great information.

Good thing I hadn't sent in an order to NAPA because I was going for another "quilted" line.

Didn't know that that connection was called a "Military Battery Connector". I can buy most of the connectors from a stereo shop locally.

Out of sheer curiosity and the desire to learn, ... and I don't want to be a bug, but what is the difference from grounding to the body and grounding to the core support., and another grounding to the firewall. Aren't all three equal ? Is this a case of more is better..especially when running efi ?
 
The factory grounding is marginal at best. Another good way is to use one of the unused bolt holes on the rear of the driver side head, run a short no4 starter cable from there to the master cylinder studs. You can buy short starter cables (eye to eye) at parts stores. It matters not whether it's braided or insulated.

The thing is, you want the main ground to the engine block............heavy starter current.

But all the lights heater, cooling fans, electric pump, etc, if used are normally grounded to the body. So you want an improvement over factory as the alternator and the loads get larger.
 
I always add additional grounds to my old vehicles too. I've chased enough marginally working electrical devices to a ground problem that I think the additional connections are a good practice. One in particular is a direct route from the neg. battery cable to the radiator core support. I also make sure the one from the engine to the firewall is clean with good connection.

The "tuner boys" go so far as claiming additional horsepower with their spider like "ground distribution kits"!!! Those probably do more for the 14 speakers and multiple video/TV screens than horsepower, but a good ground eliminates a lot of frustrations.
 
I took the ground cable off a 90's Dodge truck while grabbing the mini-starter, real cheap at PickNPull. It has flying leads to ground the engine and frame several places.
 
The headlights and park lights are grounded to the core support. Always have been.
That ground path had to travel the body to the firewall, a strap there, and across the engine to reach the battery. Result was dim or no front lights.
The short wire from battery neg' directly to the core support was added around 1970 to insure and improve front light operation.
 
...do not ground the core support with one of the rad bolts if you are using an aluminum rad...this can increase electrolosis issues
 
I usually suggest a grounding wire to the core support for the guys that are installing my relay kits on earlier cars.

Hard to have too many "GOOD" grounds. Just because a wire is hooked to something doesn't mean it's a good ground. Always make sure the base material is clean/bare and use dielectric grease.
 
I'll say this about grounds. You cannot have too many.
 
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