Question for Keith Seymore

[Tx Firefighter]

Keith,

A while back you welcomed me to ask you questions about 73-87 trucks and the engineering behind them.

My first question..

On upper door hinges, why did GM use one bolt threaded in from the inside and the rest from the outside ? As I'm working myself into heatstroke today rebuilding door hinges on a truck, I was struck with the frustration of having to access that one bolt per side from inside the truck while the rest are outside the cab and easy to get to.

Thank you for your time.
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[Redcap]

An excellent question, one I am interested in hearing the answer to as well!

[willett]

ya! I hate those damn things!!

[RandyP]

Why are you removing the hinge if you're just rebuilding, ie pins and bushings.

Don't try doing the same thing with newer trucks, it'd really tick you off having to break out your welder and air hammer.

[Tx Firefighter]

A hinge rebuild for me is full sandblast, powdercoat, and reassemble with new pins, bushings, and detent springs. They gotta come off for that.
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[ont_guy_38]

They are like that so you don,t have to remove the fender to get the one bolt out. That's my guess and I'm sticking to it !!!!!!!!!!

[RandyP]

I totally forgot about you powdercoating now. I say now, it's been a while now actually.

Can you pretty much create every color under the rainbow with that?

[bigblock73]

Kevin, what brand hinge rebuild kit are you using? Need to rebuild the ones in my 75, and want a quality kit.
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[Tx Firefighter]

Originally Posted by RandyP

I totally forgot about you powdercoating now. I say now, it's been a while now actually.

Can you pretty much create every color under the rainbow with that?

There are right at 6500 colors now. Like your paint, that can turn into millions of combinations. There's all manner of clears from dead flat to full gloss, clears with boat flake metallics, fine metallics etc. Then, the range of translucent colors which you can put over whatever color base you desire to skew the final color to whatever you want. Just like paint, a black base coat and a white base coat, or even chrome base coat with a candy mid coat will vary in color. This is my most popular color. I've coated several dozen motorcycles in it.





Lately I've been pushing the envelope a lot with laying a basecoat, applying stencil graphics in vinyl, then a topcoat, peel stencils, and clear the whole mess. I did this bike for a guy in half and half theme. It's all white basecoat, apply stencils, two different topcoats, peel stencils to expose the white, then lots of clear.









More careful masking with vinyl and multi colors. This is a heat shield on a dirt bike exhaust. I did the ceramic coating on the pipes behind it too.

Originally Posted by bigblock73

Kevin, what brand hinge rebuild kit are you using? Need to rebuild the ones in my 75, and want a quality kit.
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I ordered the hinge pins and bushings from Classic Parts. They're perfect. Unlike most, the length is right and the pins don't need trimming shorter. I also ordered the S shaped springs that go on the upper hinges to hold the door open. It's all top notch. I pretty much only order from Classic Parts lately for most all of my needs on truck specific stuff. Summit and Rock auto for more generic hard parts.
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[RandyP]

Damn, that's impressive. Guess I'm just used to hearing powdercoating and thinking black.

Did not mean to hijack your thread man.

[Stoney]

Do you have to remove the front fenders?

[Tx Firefighter]

I did but you don't have to. I wanted to do some other clean up and panel alignment work at the same time so it was much easier to yank the front fenders. Then I rebuilt all of the door stuff and aligned the doors to the cab. Then installed the front clip and aligned it to the doors. I got the gaps very good and the door operating very well, but it wasn't a walk in the park. These trucks suck for door alignment and latching if they have any wear on the parts whatsoever. Don't even get me started with the cracks I had to weld up in the doors.
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[kelsfine69]

Candy Ruby Red...I know it well.. .Now back to the question..

[Keith Seymore]

Originally Posted by kelsfine69

Candy Ruby Red...I know it well.. .Now back to the question..

I always wanted one of those

(or a Honda 50).

K

[kelsfine69]

Originally Posted by Keith Seymore

I always wanted one of those

(or a Honda 50).

K

I just finished it this spring. I have a Candy Gold one next on the list for a winter build

[Keith Seymore]

Originally Posted by Tx Firefighter

Keith,

A while back you welcomed me to ask you questions about 73-87 trucks and the engineering behind them.

My first question..

On upper door hinges, why did GM use one bolt threaded in from the inside and the rest from the outside ? As I'm working myself into heatstroke today rebuilding door hinges on a truck, I was struck with the frustration of having to access that one bolt per side from inside the truck while the rest are outside the cab and easy to get to.

Thank you for your time.
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I'm sorry my delay in responding; I'm not sure why I just now found this thread.

I didn't know the answer but I walked a couple rows over and asked one of the old (old) design engineer (he retired from GM and is now back as a contract worker). It's a process oriented thing: one guy shoots the bolt early in the build from the inside to get everything hanging, and then another operator comes along later and shoots all the remaining bolts from the outside.

This type of division of labor is not uncommon, particularly because of work load balance. Often one worker will finger start a nut and bolt and then someone else tightens them. My friend Bill (the guy with the 3 speed GTO) was telling me he used to work at Ford and was responsible to put the "F" and the "O" on the trunk lid. Someone else came along later to install the "R" and the "D".

Poor guys were overloaded. I told him it's a good thing he didn't work for "C-H-E-V-R-O-L-E-T"....

(lol)

[Keith Seymore]

Another thing that drives these seemingly unusual releases are "monuments" in the plant - large fixtures or pieces of equipment that cannot be moved without great expense and lead time.

An example of this would be on the GMT800 product. On the prior product (GMT400) the battery was located in the RF corner of the engine comparment; the engine air cleaner was on top of the fender wheelhouse and the engine coolant surge tank was at the rear (up against the front of dash).

In this configuration the coolant system could be evacuated and filled without the fender in place, which allows it to happen earlier in the process and allows operators easy access to the engine compartment.

So - new program and along comes a new air induction engineer (..."me"...) with more stringent flow restriction requirements than ever before. It became apparent that in order to minimize bends and overall length, and therefore meet the requirements, I needed to have that front corner for my air box. That meant the battery guy had to go to the front of dash (for structure) and the coolant bottle had to go to the top of the wheelhouse. Only problem with that: we couldn't fill the bottle without the fender there, and couldn't move the fill equipment because it was too huge.

Solution: add two little buttons to the radiator support to allow the coolant bottle to be temporarily "slaved" to the rad support for fill, and then moved to its final position later after the fender is installed.

The next question becomes: what do you do with the little buttons? Leave them on there? Pull them off? Re-use them? In the end we determined it was cheaper just to leave them on and let them stay there for the life of the vehicle.

So - if you look at any GMT800 product you will see those two little buttons still there, going along for the ride, for no apparent reason: All because of a new guy and because we couldn't move the fill equipment.

K

[Tx Firefighter]

Thank you for the thorough answer. I wish I could spend a year in that place. I think I'd learn a lifetime worth every day.
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[Keith Seymore]

Originally Posted by Tx Firefighter

Thank you for the thorough answer. I wish I could spend a year in that place. I think I'd learn a lifetime worth every day.
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Yep. I wish you guys could follow me around for a year, too. I think you'd be fascinated and astounded.

K

[8lugnutz]

Originally Posted by Keith Seymore

Yep. I wish you guys could follow me around for a year, too. I think you'd be fascinated and astounded.

K

I think I would be astounded after just one hour, much less a year!

[S10Fan]

Originally Posted by Tx Firefighter

Thank you for the thorough answer. I wish I could spend a year in that place. I think I'd learn a lifetime worth every day.
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Ditto

[PAWS 72]

Yep Keith we do.

[faribran]

Keith, we do appreciate the sharing of your knowledge.

[cory d]

i dont put those back on

[cory d]

also the stupid one the on front of the fender. i leave those off