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Gap at back wheels [message #122903] Sat, 23 April 2011 13:12 Go to next message
tgeiger is currently offline  tgeiger   United States
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I was talking to my mechanic about doing the isolation pads. He has been doing the brake lines and has both pairs of wheels up on jack stands as he was doing the lines. He hasn't started on the iso pads yet, but said he is seeing 1 1/2" gap between the plywood floor and the rail beam over the tag wheels. He was wondering if this was normal. I asked him if it was possibly because he has it up on the jack stands. Anyhow I told him I'd ask on this forum. Anyone have any ideas on this?

Thanks,
Tom


Tom Geiger 76 Eleganza II KCMO
Re: Gap at back wheels [message #122907 is a reply to message #122903] Sat, 23 April 2011 13:33 Go to previous messageGo to next message
Dennis S is currently offline  Dennis S   United States
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tgeiger wrote on Sat, 23 April 2011 13:12

I was talking to my mechanic about doing the isolation pads. He has been doing the brake lines and has both pairs of wheels up on jack stands as he was doing the lines. He hasn't started on the iso pads yet, but said he is seeing 1 1/2" gap between the plywood floor and the rail beam over the tag wheels. He was wondering if this was normal. I asked him if it was possibly because he has it up on the jack stands. Anyhow I told him I'd ask on this forum. Anyone have any ideas on this?

Thanks,
Tom


Tom

Here Is a photo that you might review and show your mechanic

http://www.gmcmhphotos.com/photos/showfull.php?photo=35544

An 1 1/2 inch gap sounds excessive -- but I may not understand what he is measuring.

Dennis


Dennis S
73 Painted Desert 230
Memphis TN Metro
Re: Gap at back wheels [message #122911 is a reply to message #122903] Sat, 23 April 2011 15:23 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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I am confused by your description and do not understand where you are seeing this 1.5" gap. A picture would definitely help

Where has he got the jack stands?

I sure hope they are not under the floor rather than the steel frame. If they are under the floor, MOVE THEM IMMEDIATELY to underneath the steel frame. I would be surprised that the floor could hold 4000 pounds per side without shattering it.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Gap at back wheels [message #122934 is a reply to message #122903] Sat, 23 April 2011 19:12 Go to previous messageGo to next message
mike miller   United States
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tgeiger wrote on Sat, 23 April 2011 11:12

I was talking to my mechanic about doing the isolation pads. ... but said he is seeing 1 1/2" gap between the plywood floor and the rail beam over the tag wheels. He was wondering if this was normal.


What year is your coach? (Another reason to put it in you sig line...)

The thickness of isolation pads changed during production. My '73 has full length thin strips. (So no big gaps) My '78 has thicker blocks that do leave a gap between the frame and body. I have not measured it, but I am fairly sure the gap is UNDER and inch.



Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo' http://m000035.blogspot.com
Re: Gap at back wheels [message #122939 is a reply to message #122934] Sat, 23 April 2011 19:56 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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That makes sense Mike. I could not figure out just what he was talking about. There won't be a gap in older 73-74 with full pads. I would think not over 1/2 inch if new thicker pads have been added to newer 75-78 coaches. I see where Bounds finds them smashed so bad there is no gap. Must be what he was talking about but "behind the rear wheel" kinda threw me.
Dan


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Re: [GMCnet] Gap at back wheels [message #122953 is a reply to message #122934] Sat, 23 April 2011 21:02 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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There is one place along the rear side of the frame where you have



Emery

On Apr 23, 2011, at 6:12 PM, Mike Miller <m000035@gmail.com> wrote:

>
>
> tgeiger wrote on Sat, 23 April 2011 11:12
>> I was talking to my mechanic about doing the isolation pads. ...
>> but said he is seeing 1 1/2" gap between the plywood floor and the
>> rail beam over the tag wheels. He was wondering if this was normal.
>
>
> What year is your coach? (Another reason to put it in you sig
> line...)
>
> The thickness of isolation pads changed during production. My '73
> has full length thin strips. (So no big gaps) My '78 has thicker
> blocks that do leave a gap between the frame and body. I have not
> measured it, but I am fairly sure the gap is UNDER and inch.
>
>
> --
> Mike Miller -- Hillsboro, OR -- on the Black list
> '73 26' exPainted D. -- `78 23' Birchaven Rear Bath -- `77 23'
> Birchaven Side Bath
> http://m000035.blogspot.com
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Re: Gap at back wheels [message #122961 is a reply to message #122903] Sat, 23 April 2011 22:00 Go to previous messageGo to next message
tgeiger is currently offline  tgeiger   United States
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Sorry guys should have provided more information here. My coach is a 76 eleganza. I'm talking of the floor right behind the tag wheels. The jack stand is placed under the center portion of the bogie between the wheels. I have not seen this becouse the coach is down in storage in the middle of the state. I'm up here in KC. I'm going off his description to me this morning when I talked with him. I will ask him if he could provide a picture for me to help clear this up.

Tom Geiger 76 Eleganza II KCMO
Re: Gap at back wheels [message #122975 is a reply to message #122961] Sat, 23 April 2011 23:43 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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If you have full height body isolators then the gap should be somewhere between 5/8" and 3/4". There is one place right in the area that you are describing that has a double isolator. Actually it is a 3/4" plus 3/8" isolator if I remember correctly.

I hope this is what you are talking about.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Gap at back wheels [message #122986 is a reply to message #122939] Sun, 24 April 2011 07:30 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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WD0AFQ wrote on Sat, 23 April 2011 19:56

That makes sense Mike. I could not figure out just what he was talking about. There won't be a gap in older 73-74 with full pads. I would think not over 1/2 inch if new thicker pads have been added to newer 75-78 coaches. I see where Bounds finds them smashed so bad there is no gap. Must be what he was talking about but "behind the rear wheel" kinda threw me.
Dan


This is a pic of a 73-74 style full length pad. This section did not have any weight on it and thus has not been compressed. The rest of the pads, even where under pressure, are not noticeably compressed.

http://www.gmcmhphotos.com/photos/showphoto.php?photo=24750


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Gap at back wheels [message #122994 is a reply to message #122986] Sun, 24 April 2011 08:46 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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interesting. the dust image shows the cutout in the floor was not centered
over the senders.
http://goo.gl/1rmtV

this is what I found when I cut down from the top to remove the senders
http://goo.gl/y9Ipa

also, I was under the impression the pads were flat with no indentations
when new, so this one would have been compressed to get this shape?

http://goo.gl/ZMxo0

would like to have measurements from the "relief" holes to the frame
members.... ;>)
gene


On Sun, Apr 24, 2011 at 5:30 AM, Steve Southworth <midlf@centurytel.net>wrote:

>
>
> WD0AFQ wrote on Sat, 23 April 2011 19:56
> > That makes sense Mike. I could not figure out just what he was talking
> about. There won't be a gap in older 73-74 with full pads. I would think not
> over 1/2 inch if new thicker pads have been added to newer 75-78 coaches. I
> see where Bounds finds them smashed so bad there is no gap. Must be what he
> was talking about but "behind the rear wheel" kinda threw me.
> > Dan
>
>
> This is a pic of a 73-74 style full length pad. This section did not have
> any weight on it and thus has not been compressed. The rest of the pads,
> even where under pressure, are not noticeably compressed.
>
> http://www.gmcmhphotos.com/photos/showphoto.php?photo=24750
>
> --
> Steve Southworth
> 1974 Glacier TZE064V100150 (for workin on)
> 1975 Transmode TZE365V100394 (parts & spares)
> Palmyra WI
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> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



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Re: Gap at back wheels [message #122996 is a reply to message #122975] Sun, 24 April 2011 09:15 Go to previous messageGo to next message
tgeiger is currently offline  tgeiger   United States
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Thanks Ken,

I think this is it. I had purchased the iso kit, (individual pads, not continuous), and it had instructions with it, but this will help. I sent your note down to him and requested a picture of the area to post up here.


Tom Geiger 76 Eleganza II KCMO
Re: Gap at back wheels [message #123000 is a reply to message #122996] Sun, 24 April 2011 09:33 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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I do not remember if that double pad spot between the rear wheels took two of the same thickness or one of the thick and one of the thin pads. Have him look at the instructions and verify this prior to installing the new ones. He also could leave those two spots (one on each side) until last. The he can see what sizes are left in the kit.

I did mine several years ago and do not remember exactly. On the one we did last year on one of Blaine's coaches we did not do that spot while I was there. He had a 4 bag system that was in the way. Blaine did it later after removing the 4 bag system.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Gap at back wheels [message #123020 is a reply to message #122994] Sun, 24 April 2011 11:25 Go to previous message
midlf is currently offline  midlf   United States
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Mr ERFisher wrote on Sun, 24 April 2011 08:46

interesting. the dust image shows the cutout in the floor was not centered
over the senders.
http://goo.gl/1rmtV


I thought it was well centered. It appeared that the sender was only off center from the cutout about 1/2" to the left. I will find out for sure as I am going to cut the floor for access when I reinstall the tanks.


Mr ERFisher wrote on Sun, 24 April 2011 08:46


also, I was under the impression the pads were flat with no indentations
when new, so this one would have been compressed to get this shape?

http://goo.gl/ZMxo0



Nope - I cut this piece of cushion out of the long strip in the area on the left side where all the air lines, fuel tank vent lines and brake lines pass through a routed out area in the 1" thick plywood. This pad was in that area with those referenced lines running over it. It was never compressed. (And in thinking about it I will need to reinstall it, or something, to prevent these lines from chaffing on the inside frame edge.)


Mr ERFisher wrote on Sun, 24 April 2011 08:46


would like to have measurements from the "relief" holes to the frame
members.... ;>)
gene



Can do. But probably a better reference would be from the bolt holes the gas tank front edge bolts up to. That measurement can then be correlated to the opening on the gas tank.




Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
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