Rag Joint Question- Jim Shea, Joe Lucia

[Gary R.]

Hi Guys
I just used my last new GM rag joint #7818568 on a fellow NCRS buddies steering box I blueprinted.

I went over to my local GM dealer to get another to have and noticed the ink was now purple and the rag material seems more flexiable then any of the previous GM rags I've used for years. I also noticed I didn't get stuck by the wire mesh in the rag like I usually do. Then I looked closer and found no mesh all. So I dug out the meter and checked it for continuity from the input bracket to copper stud- nothing. Then I checked the same thing on the box with Red GM rag I installed and it does ground through the rag.

Looks like I either got a bad rag or the current supplier isn't going to ground them. Correct me here, but isn't that the main ground for the steering column? Have you heard of this and would you use it? I going to return it and if this is the case not use them anymore.

Here is the current box label, same number


Here is the rag




No wire mesh


New rag - open- no grounding


New RED rag from a year or so ago- same test- grounded

[Joe L.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

Gary------


I do not know if the column is supposed to ground through the rag joint. However, I'm sure that Jim will know.

[Joe R.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

Gary,

I know the horn relay gets its ground through the rag joint. The horn won't work without it. I don't know if that ground also feeds other circuits.

Joe

[Gary R.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

I'm pretty sure it does and I've always found the GM rags grounded until now. This was one part I strongly recommended using over any of the others out there but who knows maybe they're being sourced all from the same place now? I still have a couple of the GM 67-69 rags that I bought a few years ago that are good. I can see the NOS grounded ones going up a lot if this is the way they're going to come through now.

[Jim S.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

I had heard rumors from Saginaw that their supplier could no longer obtain the screen for the screen ground flexible coupling discs. It looks like the rumor is true.

Some type of grounding system, (screen ground disc, brass strap, wire with connectors) were always a part of the GM/Saginaw flexible coupling assembly. It was a "belt and suspenders" type of situation. There are usually multiple ground paths from the steering column to the sorrounding structures and to the steering gear.

The primary path to ground was always through the steering shaft, down to the flex coupling, through the steering gear, and into the frame. However, the metal mast jacket attached to the floor pan; the heavy mounting bracket with aluminum capsules and its attaching structure to the dash, are other possible grounding paths. However, paint on the mounting brackets, mounting the steering column bearings in plastic adapters and plastic bearing housings could also prevent a ground path out of the steering column to the rest of the car.

So Saginaw always took the position that they would provide a path through the flexible coupling. Needless to say, that philosophy has now gone by the wayside.
Jim Shea

[Gary R.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

Hi Jim,
Well that doesn't sound too good. I'll be returning this one on Monday I guess. For a driver a ground wire can be fastened to complete the ground but I'll be leaving that up to the car owners to decide on.

[Jim S.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

Gary,
I am on vacation in Colorado so I don't have my reference materials available. I do see from your excellent photos that the new flange and coupling assembly has a disc with only 4 laminations of neoprene rubber and cotton cloth. I am positive that the Corvette assembly always had 7 laminations. You can count the 7 laminations on your last two photos.

Seven laminations made for a much stiffer coupling and was more correct for manual steering applications. The 7 lamination discs was always used on Corvettes regardless if it was power steering or not.

From you photos, it appears that the new flange and coupling assembly is still being manufactured from authentic Saginaw tooling. However, they are not following their own assembly drawings for correct parts.

Jim

[Jeff B.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

I bought a 7818568 joint from GM Parts Direct in late August, 2010. I received a coupling with 7 laminations.

[Gary R.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

That is one of the "red" ones like I've been using. I'm sure there are still some out there in parts depts across the country.

[Gary R.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

Gary,
I am on vacation in Colorado so I don't have my reference materials available. I do see from your excellent photos that the new flange and coupling assembly has a disc with only 4 laminations of neoprene rubber and cotton cloth. I am positive that the Corvette assembly always had 7 laminations. You can count the 7 laminations on your last two photos.

Seven laminations made for a much stiffer coupling and was more correct for manual steering applications. The 7 lamination discs was always used on Corvettes regardless if it was power steering or not.

From you photos, it appears that the new flange and coupling assembly is still being manufactured from authentic Saginaw tooling. However, they are not following their own assembly drawings for correct parts.

Jim

Jim enjoy your time in CO, sounds like a great time to be there too.

[Jim S.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

Had dinner with Lars and Donna Grimsrud on Friday night. He has nearly finished his 64 roadster. A three year labor. Absolutely beautiful. Flawless black with a 1967 427 hood and red stinger strips. 402 cubic inch small block dynoed at 496 horsepower. We didn't have time for a ride. But one of these days (years etc). He says that he can burn rubber up to 100 mph.

Snow conditions were excellent today at Beaver Creek.

When I get back to Saginaw next week, I will try and call somebody at Nexteer (the new Chinese owned company, formerly Saginaw) and try and find out who is managing the flexible coupling service parts (if anybody.)

Jim

[Terry L.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

I bought the same coupler with the magenta color face a couple of weeks ago from my local GM deal. After reading this thread I checked with another dealer in the area and they had a coupler with 7 laminates as previously described but the face was yellow. I purchased this coupler and assumed it would have the wire laminates. I checked the continuity and it does not have the wire mesh imbedded either. I guess I will be returning this coupler also and the search continues for a grounded coupler.

[Jim S.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

I will try to decode the various paint colors on the various coupling discs when I get back to Saginaw next week. (I might have some info in my reference files.)

Weather is bright, sunny, and cold today. About 14 inches of fresh snow since yesterday morning. 80 some inches of base. Should be a great day for skiing at Beaver Creek.

Jim

[Jim S.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

I have not been able to contact the current supervisor that has responsibility for the flexible coupling assembly at Saginaw (Nexteer). I have been on vacation. I will try him again today.

I did contact an engineer that worked on the C3 steering column. He seems to remember that when the bearing housing for the standard (non-adjustable) column was changed to plastic (around 1977) there was discussion about grounding the upper bearing. But he thinks that all tilt and T&T columns would have a die cast bearing housing and therefore, there should be a ground from the steering shaft, through the upper bearing(s), into the die cast bearing housing, through the tilt support, down the mast jacket, and into the dash structure.

Jim Shea

[Gary R.]

Re: Rag Joint Question- Jim Shea, Joe Lucia

I still have a couple of the GM 67-69 fine spline rags that are rigid and grounded.Has anyone bought one of these from GM lately? I suppose it would be like the 69-82 D flat rags now too.