Ground wire on distributor makes engine last longer?

Hi. Most you guys that don't know me? I am OCD about somethings. horsepower and Motor assembly is one. Here's something to think about as you put your engine together.

Points? HEI? get the ground through the distributor body, sitting on a "painted" intake & gasket (bad connection) clamped with a "painted" fork distributor hold down (bad connection) So when the DC power on the points "CLOSE" to charge the coil.. where does the DC power go? down through the distibutor shaft?, through the "lubed" bushings to the engine (bad connection), through the camshaft gear, through the camshaft with DC power sinking to ground.

Okay, what does that matter? well.. As your engine runs, it builds acids in the sump, as the oil is contaminated it gathers a PH, the filter has a ph balancer in it if you change it regular like.. but.. if not.. if it sits like most hotrods it does not run daily.

So, here we have a perfect electrolytic solution, acid and DC power causing electrolytic deplating of bearings. So.. one more thing wearing out a engine before it's time.

How I found this? well Recently I had a HEI I thought had a bad module.. swapped it out, didn't fix it, took the distributor out, it worked fine on the test bench.. put it back, no work.. too much bad connections.. So.. I am adding in a ground wire now to all my toys. I want all the horsepower I have paid for coming out the wheels.

Never really thought about it before. That ground strap flopping from the firewall for ages is going to be hooked up too. Heck, I may even run a ground wire to that huge alternator on my 57.

 

The more direct grounds the better. Dim lights, eccentric instruments, low generator output, and on and on get better with a ground wire. Best is a sort of ground harness linking everything that matters all the way back to the battery ground strap.
ALL old cars have ground issues galore...if jalopies, grounds arr blocked by dirt and rust, if fully built grounds are blocked by lots of fresh, thick paint and rubber...
I think every electrical problem that really puzzled me turned out to be a simple grond issue.

 

Great post thank you. This makes perfect sense, but I never thought about it before.

 

Don't HEIs have a ground in the plug? The older ones with the coil in the cap have to because the cap isn't grounded to the distributor. The modules and pickup coils shouldn't be grounded to the distributor either. The newer HEIs have the coil mounted to the engine block so it gets it's ground through the mount.

Points need a ground in the distributor, but the electronic systems shouldn't.

 

Not only that, but in many cases of Electronic Ignition you can create a failure by not having a good distributor ground. Chevy's are the worst for this as they use a gasket at the base of the Dist.
And those nicely painted, powdercoated or even Chromed hold downs can interrupt the ground path. Even worse when you have a bit of an oil leak that seeps in there.
Working for PerTronix, I have seen failures due to a bad ground path, sometimes intermittent problems, sometimes fatal.

 

THE HEI's have a flat strap on the coil in the cap, it goes over to the plug going to the base of the distributor module, it grounds through the distributor to the block, the hold down clamp, the gasket, the paint, the gear, then the camshaft

Most all them parts it grounds to has paint, or in my case powder coat on them. YOU do not want it catching ground through the gear and camshaft.. intermittent problems and unseen problems. Meaning instead of 40,000 volts output it maybe 20k.. or the 12 volt as it arc's to ground will jump to 1000 volts. A tiny spark is like a tiny transformer, does not make a lot of current but it can make a voltage spike.

My problem is fixed and something else to watch for in the future here.

In the 70s.. I lost a street race paycheck for paycheck cause a A-hole drew lines on my distributor cap with a pencil.. caused tracking of the spark and a loss of horsepower, ie the race.. It got serious after that. You can do the same thing with a spark plug, draw a line down the insulator. Looks like a crack, but wipes off.

 

Interesting discussion. Electrical discharge is a known cause of bearing failure in electric motors. In many instances, the bearings are the spot where any stray voltage canl discharge and the pitting seen in the bearings and races is the result. Learned this working on large pump motors at public aquariums. Basically what is created is a mini "welder" from the arcing.

 

Huh...never thought of it...Makes sense to me! I'll be trying this!

 

Then again I love ground straps...I plan on having around 5 of them on various parts of the frame, body, engine, etc!

 

never thought of grounding the distributor. it can't hurt.thanks for the tip...jack

 

Advice will be heeded on all 3 of my hot-rods. You can never have enough return paths/grounds especially if you are running an alternator and HEI. I've found the hotter/better the spark, the better this shitty ethanol fuel burns.

 

I agree with Bruce. Grounds are a problem for sure and extra grounds cant hurt.

 

thanks. i'm working on that right now as a matter of fact.

 

All my cars are grounded to hell, battery to engine and frame, engine to frame and body, guages are all grounded together and sheet metal screwed to a shiny spot. Each lamp has its own ground on the body or frame, depending, all to designated shiny spots. You can't have enough good grounds, everything works better, like most, I spent a lot of my youth chasing problems that good grounds would have prevented.

 

I have been an aircraft electrician all of my life, a number of years ago i went to work for a local firm specializing in conversions. My first job was to figure out way the alternators were not out putting, turns out they were using an 8 ga out put lead but only an 18 gauge return. Amazing how well everthing worked with a correct gauge ground!!

 

ok could someone tell this idiot where a ground wire would be attached? to the distributor to make the connection ?

 

Ground the wire from the points ….. Your engine will last forever.

 

so i wouldnt need to to do this if im running electronic?

 

I never thought of this

 

I took a ground wire off the advance on the pesky one.. on my 57, it's running a locked advance unit distributor off a school bus engine, so i may use a screw there where the vacuum advance should go.

Points distributor .. yeah I'd use the condensor screw for the gnd terminal wire.. so you can adjust with without the terminal in the way.

I used to install them chevy V8 points in everything cause I loved the way they dialed in with a screw. the 6cylinder chevy points are universal in everything from hysters to Harleys. Blue streak brand are worth the cash and wait. (or they were back then) I got HEI's in about everything.. even one from Ebay for a 302 ford.

 

Where does it go? It goes through the spark plug wire and grounds when the plug fires. That pretty much dissipates all the voltage until it builds again for the next firing. A good ground to the engine is needed, but why more than that?
History has proven that the way Detroit grounded them has always worked and not caused early demise to millions of engines. HEI's need the module to have 12v. pos. and neg. and all have that. No reason to additionally ground the body of the distributor since nothing travels through the body to run the engine.

 

High voltage "return path" is also from the coil, to motor ground, then spark plug base. Through distributor body. Through connection of hold down clamp, through base gasket, through slip fit on intake, through gear, through camshaft. High voltage will bridge a gap thou, clean it's own path.. (called arc gouging in welding) OR EDM?? or.... That is.. unless some hillbilly powder coats everything in polyester insulation.


What is cool, how new-age-non-hamb engines routinely last 2-300,000 miles.. why? the gas-air mix is better, and lil things have been resolved, like no more distributor.. When I was young, it was a big thing to get 100k out of a engine. AWW.. the 283.. imagine how long that'd last with the new age systems monitoring?

 

Spent a week trying to get spark in my old 216 chevy- finally cleaned the distriutor base
so it could get a decent ground and it fired right up.

 

Good point guys,good grounds are a must for any electrical system.had a buddy's street rod start running real shitty on a long trip.We pulled over and realized his throttle cable was smoking red hot.It was grounding it self through the cable. We made a temp ground with Jumper cables. Ran ok after that to finish trip. He over painted everything and built a nice car but didn't ground shit. I said think about it the motor and tranny are in rubber mounts and even the exhaust is hanging on rubber.

 

mistake

 

I can run wires and have wired several cars but I don't know beans about electrical diagnostics.

On a 30+ year old build on my 48 Chev I am running into a problem with the engine shutting off at cruising speed then when placed in nuetral and started again it back fires. Seems like an electrical problem rather than fuel although I have replaced all filters and check the hoses for softness.
I have also replaced the coil, unilite module and ballast resister.

Grounds???

On a "Mallory Unilite" distributor how would you ground this?

Thanks.

 

good tread i smoked one of wires on my mallory unilite ground it and it works .
for easy grounding i will try putting wire clamp to stainless hose clamp on disbrutor and on a bolt on engine block.

 

I'm afraid I can't agree with you. Electricity (especially high voltage electricity) does not take the paths you've described. High voltage electricity takes the path of least resistance, and it is always over the outside of whatever it's traveling through. In the case of an engine this path is the surface of the block, heads, or intake manifold, not through the cam, timing gears, etc.

 

It'll use a LOT less gas too...

 

That's Fer tha' Post...............What the Heck does OCD stand for ???
Yeah, I'm frum the Mts of Tenn !
An, Damn Proud ! Thanks Again for bein' Nice to ME.

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