The Stovebolt Site Forums The Shop Area Engine Shop Points squealing?

Anybody have any ideas why a newish set of points might be squealing? Been chasing this problem down for a long time. Long story short points are squealing, back them off to where they don't touch, no squealing. Why?

Did you lubricate the lobes on the distributor?

I did now 🤦🏻‍♂️

Did it silence the squeal?

Yes sir. Thank you! Kind of a no s$&@ moment, but ignorance can make things a lot harder sometimes.

Great to hear! Today, not many people heard of distributor points and even fewer know how to install and set them properly. Now we have one more to teach the younger generation.

I may or may not have had to spend all afternoon pulling the distributor to figure out such a simple source of sound...
I'm actually glad I did though, because now I know how.

If this link works, ( download PDF ) it has some information on points for the V8 engines. Pay close attention to felt wiping pad supplied with the better sets.
https://www.corvetteforum.com/forum...int-distributor-contact-sets-article.pdf

I read that GM discontinued the wiping pads for lobe wear??? I haven't been able to find the service bulletin.

At one time the AC Delco box included an instruction sheet to add a small dab of lubricant behind the rubbing block.

1954 shop manual. Distributor lubricant. Bottom left.
http://chevy.oldcarmanualproject.com/shop/1954truck/54ctsm0005.html

Some points sets even came with a small capsule of lube.

Do you think the original points for a stove bolt would have had the felt pads?

The original GM points did not come with the felt lube wick. Some distributors had one on a peg in the breaker plate. The Standard Blue Streak line had the wick in the point set & still does.

George

What did it sound like? How loud? I've never heard points squeal nor did I know it was even possible.

Very loud, I can send you a video if you have an email you want to share.

Sure. It never hurts to learn new things. If I heard a weird squealing noise I don't think I'd ever consider the points.

I'll send you a PM

Strange, started squealing again after another trip, not as bad, readjusted points, fine. I guess I'll just get a new set of points, can anyone recommend a really good one?
I was just going to order the ones from ClassicParts.com but if anyone knows of an especially good set I'll get them.
I just used dialectic grease, maybe it's not thick enough to last.

I've just been using the Advance Auto Parts brand (Carquest, I think) for the last year and a half and they've been working fine.

If your condenser starts giving you trouble, please go to the The Electrical Bay section and look up top for "Alternative Condenser Update" post. There is good news about these...but not from China (where 100% of them are made today...except for one you can get here). Good luck.

Hey! High Plains, wouldn't it be nice if we could drive over to Hot Rod Lincoln's garage (big dog chained up) and pop your distributor out and into Jerry's Sun distributor tester. I'm now skeptical about needing more cam grease. Distributor bushing squealing?

The 1954 Truck shop manual suggests a small dab of petroleum jelly. "Vaseline" is 100% petroleum jelly. See attached snip from the manual....

Grease works fine if it's applied correctly and is the right stuff. I still have a tube of Bosch points grease. It's a long-fiber grease that one puts behind the rubbing block so it's drawn onto the cam as it rotates. Good stuff. It has worked well for me for many years. I also use it on Lucas magneto rubbing blocks. There was a British version I had before that which was even stickier but I can't remember the name just now, same people that made rubber grease for Lockheed natural-rubber, wheel-cylinder cups. Maybe it was their brand, yellow and black tube. In any case, it would probably take some hunting to fine a source for either.

Applied in a very thin layer pure silicone grease or any non-migrating dielectric should be fine for this. Please keep in mind the least amount of grease you can apply to the distributor cam will be what you want. The cam will try to sling anything on it off in a centrifuge fashion, the points will naturally be constantly trying to wipe it off and you want your points to stay as dry as possible. Wheel bearing grease made specifically for disc brakes might be ok. Anything subject to migration under heated conditions won't be so good for you.

What if the problem is not about the lubricant?

Something like STP oil treatment (is that still around?) would stay on the cam like glue. That stuff is STICKY. I've used it as transmission lube in a Model A tranny. But it's not good in cold weather. When it got to freezing temps, I just about bent the shift lever.
There's a rubbing block in the grease cup that's there to keep the distributor shaft pushed against one side of the bushing (to keep the point gap constant for each cylinder). That might be dry and only causing problems when the rubbing block for the points is pushing against the cam. It's a possibility. You might check that, and put some grease in the cup.

Good point Kevin. I thought the grease cup "felt" was just to lube the bushing but it also helps keep the shaft in position? I was wondering why it was necessary for the OP to readjust the points so soon.

That it would buoymaker. Definitely a points issue though, removed the points, turned over with starter, no squeal... Dm me an email and I can send you the videos if you're curious to see. (This applies to anyone who wants to see it)
I ordered a new set of points and will see how I come out. Will eventually put Jon's condenser in.

I just remembered my mechanic saying something about bending points leaf to make more pressure, that's likely the source of my issue.
Too much pressure on rubbing block, extra friction, boom, squealing, dry rubbing block.
Which likely wore prematurely, thus closing the points gap and screwing with timing.
You'd think it would take a lot of extra pressure, but maybe not.

The arm of the point set should never be bent for adjustment or any other reason.

We would always bend the fixed point contact, not the movable arm, to align points. That was one of the routine things to do when setting up a distributor on the Sun tester. Eyeballing the tiny arc as the points would make and break would give an indication of point alignment.
Jerry

Bending the points isn't going to change the pressure on the cam at the rubbing block. The only thing that will do that is changing the spring on the points or moving the pivot point away from the cam. Basic geometry says that.

I'm not sure exactly what he meant, but it sounded like it was the springy leaf part that bends around and attaches where condenser attaches. Either way I'd like to rule that out and points are cheap.

I also agree on changing the points out. Cheap, and easy.

I believe what HotRod meant, was the alignment of the (fixed to movable) contacts. Bending the fixed side only to get full contact.