R hood question???

[Bigdogtrucker]

Got lucky and picked up a pretty nice hood for my "75 686, came off the exact year and model! When did they go to the smooth fenders without the "body line" in them? 

[57 bcr]

Good  question,BDT. I'm thinking around  '81  or so when the CMCAC  came into  the  picture. Al  

[kscarbel2]

Up thru 1981, the R-model used a 1QM5480B hood (pre-CMCAC).

From 1982, with the advent of the CMCAC-equipped R-model, the hood changed to the 1QM5556.

CMCAC - Chassis Mounted Charge-Air Cooling

[Vladislav]

So did all the short hoods (non-CMCAC) have the rib on fenders?

 

Working on my (later) R-model hood I found out it was glued together of different fiberglass parts. The outer skin seems as the main structure and the inner surface formed up on the different matrix. Then they put together. It seems either there were more parts used in one hood. You just difficult to figure out how many looking a solid one.

So too probably those horizontal lines on early hood fenders are just split areas between them.

[blackdog2]

77 x-tra  rib must of been a different supplier .

[kscarbel2]

11 hours ago, Vladislav said:

So did all the short hoods (non-CMCAC) have the rib on fenders?

 

Working on my (later) R-model hood I found out it was glued together of different fiberglass parts. The outer skin seems as the main structure and the inner surface formed up on the different matrix. Then they put together. It seems either there were more parts used in one hood. You just difficult to figure out how many looking a solid one.

So too probably those horizontal lines on early hood fenders are just split areas between them.

Vlad, our original hood supplier had inconsistent quality due to old manufacturing processes. The dealers returned quite a few defectively manufactured hoods. The plant, dealers and customers painted and mounted hoods, only to discover defects. And regarding the parts distribution centers, shipping and the dealers, the wood crating was poor.

But then we switched suppliers, and both the quality and packaging became very good.

The original supplier's hoods were light gray in color, while the second supplier's hoods were dark gray, almost black.

The first supplier was Structofab, and we replaced them in May 1990 with the vastly superior Rene who used the latest manufacturing processes.

I just remembered all this, as we'd touched on it relating to that plant fire. I haven't thought about these things in MANY years (http://www.bigmacktrucks.com/topic/39396-mack-production-line-fire/#comment-284274).

 

[Vladislav]

Kevin, these facts are pretty interesting, as usual.

Although they initiate a new question from my side.

You stated that the hood supplier was changed in 1990 and pre-date hoods were gray.

That doesn't corellate with at least two R-model hoods I have. Both trucks were built in 1988 and both hoods show black (dark gray) gel coat under primer.

They sure could be swapped later. Any other reason?

[kscarbel2]

Vlad, this is a long time ago. I know we finally cut off Structofab completely in May 1990. But I believe we began phasing in the Rene product before that, to make sure they could satisfy us before cancelling Structofab altogether.

You guys have me recalling a lot of old Mack history.

[1965]

11 minutes ago, kscarbel2 said:

You guys have me recalling a lot of old Mack history.

That's what we like!!! Or me anyway!

[BillyT]

You guys are walking parts books lol

[Hobert62]

12 hours ago, 1965 said:

That's what we like!!! Or me anyway!

I'm just baffled someone can rember all this!     I have a hard enough time remembering  if I turned the lights off.