| Re: [GMCnet] Body pads on a 78' [message #269469] |
Mon, 12 January 2015 12:01  |
BobDunahugh
Messages: 2465
Registered: October 2010
Location: Cedar Rapids, IA
Karma: 11
|
Senior Member |
|
|
Years ago I found that all but one of my pads had come out on our 78 Royale. I measured the uncompressed part of that one. It was 5/16th thick. I got some of that horse pad that was 1/4th on an inch thick plus the raised ribs. That martial was slightly softer then the original pad. But then again original pad was 26 years old at that time. Plus my thought was that the softer material might deaden more sound. It's worked fine. And the road noise was greatly reduced. I didn't want to go thicker. As I was concerned about the bolted pads, and there height after all the years of being compressed. I didn't glue, of secure the new pads. No movement has been seen since. Bob Dunahugh 78 Royale Member GMCMI
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
|
|
|
|
|
|
| Re: [GMCnet] Body pads on a 78' [message #269524 is a reply to message #269475] |
Mon, 12 January 2015 19:04  |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Daniel,
Don't bother doing the job half way and cheat yourself out of the full
benefit of the job. It's really not all that hard and the improvement in
the rattles is absolutely amazing. You'll silence a lot you don't even
realize are there. The old pads ARE crushed.
I did mine 8-10 years ago and found it quite easy. As has been suggested,
I jacked beneath the aluminum floor joists. Where there are saddle clamps
securing the body to the frame, I loosened the bolts -- AFTER jacking so
that those carriage bolts were securely held into the plywood.
A very useful tool was an 18" long flat pry bar -- one of those with one
end turned up at about 30* and sharpened. Many of the old pads were
difficult to loosen until that pry bar was inserted between them and the
body or frame to which they were stuck -- that popped them right out.
I used Liquid Nails and a drywall screw or two to make sure the pads never
become displaced.
JWID,
Ken H.
On Mon, Jan 12, 2015 at 1:22 PM, Daniel DeLuca wrote:
> Bob,
>
> I think that is what I am actually going to do. Replacing the missing
> pads with some 1/4 inch horse mat. If most of my pads were missing I might
> be tempted to increase the gap as others have suggested but since most of
> mine are still there and don’t really look too crushed it seems silly to go
> ripping them out.
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
|
|
| Re: [GMCnet] Body pads on a 78' [message #269528 is a reply to message #269527] |
Mon, 12 January 2015 20:06 |
Hal StClair
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
|
Senior Member |
|
|
The pads need to be on the stringers, not the plywood floor. It's a real easy job, two hours should get it done. That's all it took on mine anyway.
Hal
"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane."
1977 Royale 101348,
1977 Royale 101586, Diesel powered,
1974 Eagle Bus 45',w/slideout,
Rio Rancho, NM
|
|
|
|
|
|
|
|
| Re: [GMCnet] Body pads on a 78' [message #269540 is a reply to message #269527] |
Mon, 12 January 2015 21:53 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Larry,
I would not leave the old pads in place. They're now about as hard as the
aluminum they're separating (sort of) from steel. Putting new rubber on top
of them would only add unnecessary space, IMHO. Removing them with the
suggested pry bar isn't difficult -- put the sharp end of the bar along the
rubber/aluminum interface and hit the other end of it with a hammer. Quit
thinkin' & start doin'. :-)
JWID,
Ken H.
On Mon, Jan 12, 2015 at 8:42 PM, Larry Davick wrote:
> Ken,
>
> Considering the body pads - if it's difficult to remove the old pads - is
> it really critical to remove them? Could you simply slip the new full size
> pads near them, screwing into the plywood, and lowering the body back down?
>
> I haven't done this job yet, but as lazy as I've become I'm trying to
> out-think any extra work that might come my way!
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
|
|
| Re: [GMCnet] Body pads on a 78' [message #269562 is a reply to message #269552] |
Tue, 13 January 2015 09:29 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
You guys are WAY over thinking this project. Follow Ken Henderson's and Jim Bounds' recommendations and just do it.
I have done 3 coaches now.
One had thin pieces, one had full length thin strips, and one had thick ones. You are worried about whether the new pads are 5/16" or 1/2" or 5/8". I would go go with the thick ones no matter what the removed ones were. The slight difference makes no difference when installing them and the thicker ones give a quieter ride. You are not dealing with a 26 (or 23 foot) brick here. The body flexes and that much difference over 26 or 23 feet is nothing. Think about what you have now with some of them missing. The body flexed and rode directly on the frame. The slight difference in thickness will not change a thing when installing them.
On my first installation I made way too much out of the project and it took me about 6 hours to do one side. I did loosen the hold vertical bolts on that side. On the second day I loosened nothing and did that side in about 2 hours.
On the second coach we loosened NOTHING. A simple jack to push up on use aluminum cross beam, knock out the old ones if present, Put a little glue on the new ones and slide them into place.
Both of the above coaches we did laying on the floor.
On the last coach we did on a hoist. It had full length strips and the owner wanted the thicker 5/8" pads installed. The biggest pain on that one was getting the old strips out since all cross aluminum pieces had to be lifted at the same time. We did loosen the old down bolts on it but we loosened the horizontal bolts holding the hold down mounting bracket. On each one we took one bolt out and left the other one loosely installed in place. That gave us some additional clearance and we did not have to worry about spinning vertical bolts in the plywood floor. The key to doing this is to leave the remaining bolt as loose as possible with the nut still it. Then on reassembly use a centering punch (I think the tool is called a drift tool) in the open bolt hole to hold the bracket in place while you tighten the first (never removed) bolt.
So quit over thinking the project and just do it. Or take it to Jim Bounds and have him do it. It is a good time of year to go to Florida.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
|
|
|
|
|
|
| Re: [GMCnet] Body pads on a 78' [message #269574 is a reply to message #269469] |
Tue, 13 January 2015 10:53 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
|
Senior Member |
|
|
Bob I couldn't agree with you more. No matter what car forum I vist even the C4 ZR1 guys, there is this thinking that more and bigger is better. More fuel pressure, colder thermostats, more ZDDP and on and on. They all know more than the GM engineers and have no understanding of how systems interact as a complete vehicle package. The body pads do need to work in concert with the body mounts. The body mounts should not be in Pull apart mode as the pads are so thick. Same as when the different divisions taylored the suspension to get their ride where they liked it for their brand. Of course rubber has a life span and 40+years is 3 lifespans. So they do need replacing with a similar thicknes when loaded material. The only way I can see improving this is that since rubbber compounds have changed in the 50 years since the GMC was first drawn, there might be a better suited replacement material. I'd have to research this but there are shock and energy absorbing compounds now that might work. Sort of the opposite of the Whamo Superball where you drop it and it bounces as much as a handfull of bread dough. The trick would be to combine that with the same durometer rating ( or more precisely the same ammount of dimensional compression under load) as the original in the same thickness as the original.
John Lebetski
Woodstock, IL
77 Eleganza II
|
|
|
|
|
|
| Re: [GMCnet] Body pads on a 78' [message #269606 is a reply to message #269579] |
Tue, 13 January 2015 15:38 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
BobDunahugh wrote on Tue, 13 January 2015 12:22
John. I like the idea of finding a compound that has more energy absorbing characteristics. That has alot of merit.
Ken does have a point that the frame, and body move, and flex alot. And GM knew that. I just question the idea of adding another element of flex into the GM design. And yes. We all have a tendency to over think things here. But that's were new, and interesting ideas come from. To me. This is like the 1 ton discussion. I've installed 2 on other GMC's. Inexpensive way to replace alot of bad parts. Good simple way to solve a problem. I just don't like the geometry change to the suspension. The only problem with the original set up was the bore for the bearings. So I put reworked knuckles on with grease fittings. So that problem is now solve for my life time. We just have to hear all sides. And do what seems right to satisfy our own comfort levels. Bob Dunahugh 78 Royale Member GMCMI
Bob,
I wasn't picking on anyone with my "over thinking" comment. I was just trying to point our that many people were making this project harder than it really is. When I first did my coach I did the same thing until Colonel Ken got on my case and pointed out what I was doing or thinking wrong. The flat slightly rounded crow bar that he suggested was the real trick to getting out the old ones. Mine on my 1976 coach were the thick (probably 5/8") ones unlike the earlier thin ones on Dan's and Blaine's coaches. Mine had had been squished down to around 1/4" or less and some were missing. Restoring it to 5/8" allowed more room for air cleaner height and also made room for the previously squished gas, air, and propane lines again.
I just wanted to re-enforce what Jim Bounds and Colonel Ken had suggested. They both usually know what they are talking about.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
[Updated on: Tue, 13 January 2015 15:40] Report message to a moderator |
|
|
|
|
|
|
|
| Re: [GMCnet] Body pads on a 78' [message #269613 is a reply to message #269608] |
Tue, 13 January 2015 16:21 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
RF_Burns wrote on Tue, 13 January 2015 16:01Well I'm sorry I put my 2 cents worth in here, I was just trying to make others aware of my experience.
I can't see where that body is suppose to flex enough to get the pads changed. My frame just rode up with the body till something in it gave way. Now I have waves in the lower SMC now and a cracked open seam on the upper aluminum.
Bruce, Please do not take offence. I did not mean to pick on you or anyone else. Obviously your experience doing this was different than mine and should be expressed. I have no idea what happened on yours but your observations should be posted as a warning to others.
Ken B.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
|
|
|
|
|
|
|
|
| Re: [GMCnet] Body pads on a 78' [message #269635 is a reply to message #269469] |
Tue, 13 January 2015 22:29 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
|
Senior Member |
|
|
I probably over reacted earlier in my post after hearing how guys want to modify cars that should be left alone on the other forums and Wastebook. I think we are the best educated and most willing to help bunch right here. Bob I think it has to be a firm material in compression and sheer planes that abdorbs energy and I would think converts it to heat If all else fsils there's used tire sidewalls. They have been making new muffler hangers from dead tires forever, but that's old tech. The new stuff is used in equipment shock and vibration isolation.
John Lebetski
Woodstock, IL
77 Eleganza II
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
