Fiberglass Ram Air Scoop to Grille

Carl Stouffer

Well-known member
Jan 15, 2009
4,693
381
83
Tucson, Arizona 85718
I have one of these: http://appliedgmc.com/prod.itml/icOid/574 and I had it mounted to my grille with a couple of bolts and nuts. Not surprisingly,
the brittle plastic broke where the bolts were installed. I can reinforce the plastic with some aluminum strap, re-drill the holes, and mount it the
same way, or I could epoxy the scoop to the grille and make it a permanent part of the grille.

I'm looking for opinions on the pros and cons of gluing it in versus bolting it the way it was with some reinforcement in the plastic.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
If you epoxy it in place Carl and decide on a new grill later, how tough do you think it will be to remove to install in the new grill? I'd vote to
bolt it back in I think.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM
 
That makes sense Hal. I guess there's no sense in buying another one at that point. A new grille is probably a given at some point.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
I had the same problem. I'm doing some ABS restoration on my grill and think I found the cause. The grill is hard ABS and has become even more brittle
over the years. Hanging the duct and hose on the back of the grill acts like a cantilever and transfers any vibrations from the duct to the grill.
This fatigues the thin ABS of the grill causing it to break. Either gluing or bolting will work but will just move the weak point to a different
place. The only remedy would be to support the back of the duct or rubber mount it to eliminate the stresses from the vibrations.

We use springs to mount the grill so it move separately from the flexing body to keep from cracking the grill and breaking out the stud bosses. Same
basic principal with the duct. I am moving mine to under the bumper.
--
Patti & Jerry Burt
73 Gmc 26' Canyon Lands -
77 Palm Beach
Members: FMCA - GMCMI - GMCWS
 
I actually have it kind of passively supported by the rubber baffle I installed at the side of the radiator. I just think the old ABS grille is too
brittle to handle anything attached to it without reinforcing. I have reinforced that area along with a couple other areas where I had some cracking
by using JB Plastic Epoxy and thin aluminum strips about 3/4" wide X 1/16" thick.

I have had good luck with regular JB weld on previous grille repairs, so using the stuff specifically formulated for plastics should work even better
(I hope). I guess I will re-drill the holes and mount the scoop the same way as before, but with the aluminum reinforcing in place this time.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
> I actually have it kind of passively supported by the rubber baffle I installed at the side of the radiator. I just think the old ABS grille is
> too brittle to handle anything attached to it without reinforcing. I have reinforced that area along with a couple other areas where I had some
> cracking by using JB Plastic Epoxy and thin aluminum strips about 3/4" wide X 1/16" thick.
>
> I have had good luck with regular JB weld on previous grille repairs, so using the stuff specifically formulated for plastics should work even
> better (I hope). I guess I will re-drill the holes and mount the scoop the same way as before, but with the aluminum reinforcing in place this
> time.

Carl,

If your grill is like mine, you could well be able to pick any epoxy including JB-weld off the surface. My grill has more than a few repairs and the
only thing that has worked on all the ABS in the coach is black ABS pipe cement. It works, boy does it work, but it is no fun to use at all.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
The old JB Weld I used has adhered very well. No peeling off the surface. So far, this newer JB for plastic seems to be working. time will tell.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member