Does anyone reproduce the conical washers which are used to fasten the bumper brackets to the frame? These would be the large washers with the square opening to allow for the shoulders of the bumper bolts. I have checked the AMK site and they do not offer them. Cheers
Your description and/or idea is wrong. Main brkts are held to frame with carriage bolts with serrated washers.....1/2-13 thread and about 1.25" long. Bolt goes thru the frame and has a square shoulder which moves in the slotted hole in the frame horn....then goes thru the brkt, then the washer and finally the nut....see pic.
George, That is the set up for Flint cars. Cars from the GMAD plants, Framingham, Fremont etc, use a hex head bolt, nut, and 2 of the serrated washers per location. Thought I would help. Duane
Hi Duane I need some clarification. My shop manual shows a bumper bolt with the square shoulders, going through what I call a conical washer which has a square opening and serrations around the perimeter, then through the frame and bumper bracket and finally finished with another conical washer (round hole not square) and a nut. As my car is a Framingham build car, would this be the correct setup? Cheers
Thanks Duane! Apparently not 1 Buick Skylark from any other plant found its way to FL......never seen one w/o the bolts/nuts/serrated washers I pictured......amazing.....also goes for all the Cutlass, LeMans, Chevelle, Monte Carlo, Grand Prix from the same years 70-2...learned something new today!
George, The home plant for Florida & Georgia was Flint. If you saw the other style bolts on a Buick it was an "import" to your area. I am pretty sure the Lansing Michigan OLdsmobiles used the carriage bolt set-up as well. Are all the Olds in your area from Lansing? My 70 442 built in Linden NJ has the GMAD style set-up. Duane ---------- Post added at 09:50 AM ---------- Previous post was at 09:20 AM ---------- Randy, I don't have a 72 Chassis Manual so I cannot see the page you are looking at, but the drawing/photos in those books are often generic. Many are taken directly from the assembly manuals but you have no way of knowing which year or model they are from. Anyway I pulled out my 72 assembly manuals and checked. The early version shows the bolts exactly like we talked about above. Flint set-up Carrige bolt thru frame & bracket, then a single toothed washer, and finally the nut. GMAD set-up Standard bolt, then toothed washer, then thru frame & bracket, then a second toothed washer, and finally the nut. When I checked the later version assembly manuals they removed the GMAD style set-up and only use the Flint style carriage bolt assemblies. This change occurred on 3-6-72, so only the late GMAD cars were changed over. So the sytle set-up you need for your 72 Framingham car depends on when it was built. I never knew this to be the case, you learn something new everyday. If you look closely at the page in your Chassis Service book you may see the bolts/washers called out as (Flint) & (GMAD Only) if so you will see what I am getting at. It's really confusing how they wrote it up and took us a while before we understood what we were seeing on the cars. Hope this helps. Duane
Hi Duane This is much better thanks. The Chassis manual does not make reference to GMAD, but the Assembly manual does. My car was made in November of 1971, so I surmise that my bumpers were fastened using the standard bolt and washers and not bolts with shoulders. Cheers
You did not look at AMK very hard. They do offer the correct serrated washers. The GM part number is #1362249. If you go to the back of their catalog and look up the GM #. It will tell you the page...AMK has a $30 Minimum but Ames Performace Pontiac also sells them....As far as the carraige bolts all Flint cars I have taken apart had them. I know because it is always an ordeal to get them off. The square section under the head is very short to allow for the bumper bracket to pivot while the square section hold in the frame. It rounds off very easily and the thing just turns. You cannot get these type of carriage bolts any more so I made my own but grinding down the square to work like the originals. I have also worked on may Lansing built Olds that also had the carriage bolt setup. ---------- Post added at 01:45 AM ---------- Previous post was at 01:39 AM ---------- Randy, Are you sure about a square hole? Assembly manual shows two serrated washers for each location if useing A reagular bolt. If you use a carriage bolt only one washer is used and the square holds in the frame. ---------- Post added at 01:47 AM ---------- Previous post was at 01:45 AM ---------- To clarify. If using carriage bolts. You need one bolt, One serrated washer and one nut for each location..................................................If using regular bolt then one bolt, two washers and one nut for each location.
HI Dave I saw 1362249 listed on the AMK site, but in the image it does not have a square hole. I surmise I made the error of thinking the washer needed a square hole to accommodate the square shoulder on the bolt. So, after all is said and done, I may not need anything additional as my current setup is as you described (bumper bolt through bracket and frame followed by serrated conical washer and nut. I guess I failed to make the distinction between GMAD and Flint in my assembly manual. Cheers
Randy correct. No such animal as washer with square hole for that. If there was then the bolt would just spin when you tried to tighten it. The squear head is meant to hold firm inthe frame. So you ony need one toothed waher each location if carriage bolts method.
