Author Topic: GM Entry Door Adjustment  (Read 3986 times)

Offline richard5933

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GM Entry Door Adjustment
« on: November 21, 2020, 03:53:03 PM »
The entry door on my 4108 works well - it opens and closes with the dash handle as it should. I'm able to push the door handle over the center lock and lock the door in the open position, and it latches fully in the closed position with the door sealed well against the door opening.

Only one problem...

I'm not able to latch the door from the outside by slamming the door. No matter how hard, the handle will not go over the center to the latched position, meaning every time I leave the bus I have to use the deadbolt to secure the door.

The manual shows two types of adjustments. There is one on the main rod that connects the handle to the door. It can be lengthened or shortened using the turnbuckle. The other adjustment(s) are the two handle lever stop screws which control handle movement in the open and closed positions.

Question...

Which of these adjustments am I needing to make to allow the door to put the handle over the center when slammed from the outside? The control rod or the stop screws?

If the control rod, would I want to lengthen it or shorten it?

If the stop screws, which one and in which direction?

Yeah, I know that I can just experiment and try things out, but I don't want to mess with something unnecessarily and screw up something that's working right now.
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

Offline Fred Mc

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Re: GM Entry Door Adjustment
« Reply #1 on: November 21, 2020, 04:39:15 PM »
Lengthen the rod.

Funny related story
A year ago we were heading to the US for camping(we live in Canada). When we got to the border customs pulled us in for secondary inspection. I parked the bus at the side of the road where there was no kerb so the rf wheel was on the dirt (which was slightly higher than the road). This caused the bus to twist every so slightly BUT enough so when I closed the door the handle went over center and into the locked position.The rod that opens the door from outside the front had been removed long ago. So in we go to the customs office. They said they were going to look inside the bus and to make sure we had taken any cash off. I said casually "don't let our 2 dogs out".They got all excited and said we had to take the dogs out and put them in cages near the office. So we went back to the bus to take the dogs off only to discover the door was locked. After some thought I took a ladder we carry out and with the rod we use to pull down our awning managed to open the door. We took the dogs out and  I slammed the door not realizing WHY it had locked in the first place. So we go into the office and 2 inspector  go out to look inside.You guessed it, the door was locked so they came back in to get the keys(?) I said there are no keys but I can open it for you.THEY SAID NO, YOU CANT GO NEAR IT.So I said fine, suit yourself but if you want it opened Ill have to do it. Hmmm, they said, well ok. The one  young (punk)customs officer said "where are the keys" to which I responded" there are no keys. So he said how do you start it.I said just push the starter button.Well, he said what about the bays and I said they don't have keys either. So I unlocked the door for them and they arrived back at the office a few minutes later with a handful of tomatoes that apparently you can't take  into the US. I later adjusted the rod.

Offline richard5933

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Re: GM Entry Door Adjustment
« Reply #2 on: November 21, 2020, 06:01:37 PM »
Lengthen the rod....

Good story - glad it all worked out in the end.

I thought at first that lengthening the rod would do the trick. But, if I do that will it mean the door won't be pulled closed as tightly?
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

Offline Fred Mc

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Re: GM Entry Door Adjustment
« Reply #3 on: November 21, 2020, 11:55:57 PM »
As you know when you use the handle the  last 1/4 turn or so  requires more effort as it is pulling an already closed door tighter. You don't need to lengthen the rod much.THe connector "nut" has right and left hand threads so I would try a 1/4 turn to start. Its not to difficult.On my 4106 I moved the location of the handle to accomodate a new dash so had to take the rod out and shorten it.

Regards
Fred

Offline chessie4905

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Re: GM Entry Door Adjustment
« Reply #4 on: November 22, 2020, 03:36:29 AM »
Watch where you give the extra effort to close your door after adjusting it. Many 4104's and up have a concave panel from doing it. Go ahead and experiment. Make note of every change, so you can return to base, if necessary.
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline richard5933

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Re: GM Entry Door Adjustment
« Reply #5 on: November 22, 2020, 04:01:37 AM »
Watch where you give the extra effort to close your door after adjusting it. Many 4104's and up have a concave panel from doing it. Go ahead and experiment. Make note of every change, so you can return to base, if necessary.

Am I correct in assuming that lengthening the rod as has been suggested will not pull the door any tighter? If so, then it shouldn't do any damage to the door to try it, correct?
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

Offline dtcerrato

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Re: GM Entry Door Adjustment
« Reply #6 on: November 22, 2020, 06:11:39 AM »
After purchase of our bus when under the dash board abandoning the door handle set up we noticed some aftermarket reinforcement placed in the handle area so there is substance to the mention of deformation of the dash in over adjustment which isn't the reason we abandoned it. Just wanted a better entry set up for a bus turned to motor home...
Dan & Sandy
North Central Florida
PD4104-129 since 1979
Toads: 2009 Jeep GC Limited 4X4 5.7L Hemi
             2008 GMC Envoy SLT 4x4 4.2L IL Vortec

Offline buswarrior

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Re: GM Entry Door Adjustment
« Reply #7 on: November 22, 2020, 08:05:20 AM »
Entrance doors suffered mightily in revenue service. All the mounting points beat to hell by running into stuff, whacking poles, accident twisting...

Be wickedly careful how much adjustment you do at a time. Mark it like a surgical instrument before starting... Some of these are hair trigger balanced, there simply is no good balance on some. You may open Pandora's box, be careful what you wish for... yours could be as good as it can be already.

Having the door handle click when just camping is a sure way for the others to get a hate on for the coach... pushing the button gets old really quickly...

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline chessie4905

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Re: GM Entry Door Adjustment
« Reply #8 on: November 22, 2020, 08:08:21 AM »
Not a big issue on GM's. They designed it well, not just copied like other mfgs.
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline richard5933

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Re: GM Entry Door Adjustment
« Reply #9 on: November 22, 2020, 10:41:45 AM »
Entrance doors suffered mightily in revenue service. All the mounting points beat to hell by running into stuff, whacking poles, accident twisting...

Be wickedly careful how much adjustment you do at a time. Mark it like a surgical instrument before starting... Some of these are hair trigger balanced, there simply is no good balance on some. You may open Pandora's box, be careful what you wish for... yours could be as good as it can be already.

Having the door handle click when just camping is a sure way for the others to get a hate on for the coach... pushing the button gets old really quickly...

Happy coaching!
Buswarrior

Don't think this is a wear issue - the bus only had 41,000 miles on it when I got it, and it has not worked since then. I suspect it's an adjustment issue.

Hopefully I can adjust it so that it can be slam latched, but have it not be so sensitive that it constantly latches on its own at the slightest touch. I haven't seen one that sensitive yet though.
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

Offline Fred Mc

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Re: GM Entry Door Adjustment
« Reply #10 on: November 22, 2020, 11:16:33 AM »
Lengthening the rod will put less pressure on the mechanisms.And its an easy process to do so you can make minor adjustments until you get it like you want it.

Regards
Fred

Offline Uberbus

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Re: GM Entry Door Adjustment
« Reply #11 on: November 30, 2020, 06:40:39 PM »
The mechanism on our Silversides will not latch from the outside no matter how much you lengthen the rod. It does catch from the inside handle just find though.  Wish I knew how to fix it!

Offline richard5933

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Re: GM Entry Door Adjustment
« Reply #12 on: December 01, 2020, 02:58:43 AM »
Funny thing, in working on the recent air leak issue I slammed the door this weekend rushing in and out of the cold. Out of nowhere, it decided to slam latch.

I'm guessing that there is still hope on my bus for it to work again with just a slight tweak.

Uberbus - have you lubricated the mechanism under the dash?
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

 

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