The Stovebolt Site Forums The Parking Lot Panels 'N Burbs Radiator Support carriage blts

Rebuilding a stock 3100 panel (1949) 1/2 ton. Installing the rad support and don't have the 2 bottom bolts to mount the support to the frame (never did). Looked on some part sites with no luck. Going to Home Depot next. I'm sure I can find something just asking if any member has a tip or part find from before. It's a driver so I don't need OEM. Thanks.

Classic parts.com. #78-671. I think that's what your looking for

direct link to the bolt assembly - one unit-assembly (two assemblies are needed)

Plus around $10.00 shipping

The originals were fine thread with castellated nuts with a transverse hole near the end of the bolt for a cotter pin.

they are hard bolts, grade 8
if you just want to use generic hardware make sure to get the good stuff, grade 5 or grade 2 is not enough for this location

(that part at classic i doubt is hardened steel)

Thanks for the info!!

Not to be snooty, but the one's linked by Tim would be just fine. A hardware store gr 5 would be plenty strong in that location or any location. 6000 PSI each for 5/16. No need for grade 8 on an old truck. Sorry, it's the engineer in me. Everytime someone says gr 8, I'm going to explain it's not required and an expensive mega overkill.

They only need to be torqued to 20 ft-lbs. I used stainless carriage bolts. Messing with the rad hoses and t'stat means a lot of fluid ends up on those bolts. The nuts on the plated ones I had there originally were frozen on.

I have a rubber pad and some shims between the frame and radiator supports. Still not happy with the fit of the fenders and hood, but it's an old truck and perfect is the enemy of good.

"perfect is the enemy of good". That line is a good line. It says what is true most of the time.

One thing that takes many years to learn is when to "stop".
Whether it's tightening a bolt or smoothing concrete or arguing.

Aren't you supposed to torque them till they break and then back off 1/2 turn?

I would challenge anyone to find a fine threaded carriage bolt. That just goes against their normal purpose.

Torque till elbow clicks.

That's good too. Haven't heard that one.

Until just before it gets looser.

Yes on smaller bolts, that happens. That's why you keep your hand near the ratchet head and not out on the handle. I mean, what grown man uses a silly torque wrench.
Muscle memory is what us mechanics use because it's.........................I forgot the rest.

I'll be replacing mine soon and I'm not looking forward to it.

Blow up the picture of the bolts available from Classic Parts, from the link Tim posted above. I can see four lines on the head of the bolt on the left, two straight up and down and two more in between. Add the two that you don’t see and that would suggest it is a grade 8 bolt.

Portland Bolt

They may be gr 8. $10.94 is too much.

My comment was that grade 5 is plenty adequate for this location. Most local hardware stores will not have gr 8 carriage bolts. Internet has many.

I agree that grade 5 would be enough and I agree $10.94 is too much. I was only pointing out that they were not you standard hardware store bolt. None of the big box stores, Ace or True Value carry grade 5 carriage bolts in my area. The internet does have many, but again your paying shipping.

With Classic Parts, I usually wait until I have at least $90 in my cart then the $9.99 shipping isn’t so bad unless I absolutely need the part, then I’ll eat the cost of shipping.

If you have Amazon Prime, you get free shipping on the bolts - steel/stainless-steel.

The grade/strength might be a concern?

I use stainless from Totally Stainless - bought/installed many years ago - I think they give a grade rating.

www.totallystainless.com/TechArticles.html

As far as what grade bolt to use for this application is concerned, when there is a failure in this area, it is the crossmember hole which gives out before bolts do.
The entire weight of the front clip rests on this tiny footprint on the crossmember. A good way to tell if your truck was originally subjected to off-road farm work would be to look at the condition of the crossmember under the radiator support.
There is a rubber pad and a shim or two between the radiator support and the crossmember. As the rubber pad gets beaten senseless, there will be slop there which will create a significant amount of hammering, causing damage to the crossmember and wallering out the holes, while the bolts will remain just fine.

Agree 100%.
Been there - Seen that. Have the Crossmember.

What is a good way to build up and repair that wallered out hole? I’ve been thinking about welding a washer underneath the hole on the crossmember

I wouldn't say entire weight. Some of that is pulled from the cowl supports. IF tensioned properly

That's correct Tom, but consider a plate of decent size that fits the shape of the area. 3/16 thick. You probably should bolt it all up and get it correct, then tack weld plate. Then if you ever need to take apart it will stay exactly aligned. Just tack weld, no need for mega weld. The welds won't add any strength anyway and tacks will heat the frame less.

I would cut out a square shaped hole outside of the footprint of the feet of bottom of the radiator support, then butt weld a square patch in place. Drill new holes and you are done.
This will retain the proper height relationship between the crossmember and the radiator support to ensure proper front clip alignment.

Would you consider that the "majority of the weight of the front clip (including the radiator and radiator support) rests on this tiny footprint on the crossmember" to be accurate?

Sure!

Awesome! I'll never match your tenacious metal fab skills. I can only hope to keep up with your literary profundity.
Carl

Watch your language, Carl.

Please try to stay on topic for archival purposes and whatnot...
An example of archival turmoil cause this type of cavalier behavior can be witnessed by typing, "no, you're stupid, Fatso" in the search bar at the top of the page.
Unacceptable and unproductive behavior in my estimation.