WTMFF? Broke My Radiator- Sort Of.

Interesting development. While disassembling the front end of the engine bits, I decided it was time to drain the radiator. Petcock open, no problem, now just to go vent the top to do a good drain. Push the cap in, give it a twist...remove cap, something doesn't look right. There's a brass arc-shaped piece about an inch long sitting in the top of the radiator cap gasket area. Look at the radiator and a piece of the friggin secondary gasket (top gasket) land had broken off the neck! Surprisingly, from what I can see, the innards don't look horrible. But I can't trust just looks. Gotta be tested.

Sad. Anyway, the radiator seems to be in good shape otherwise, as it's had a screen installed in the front of the condenser all its life. No bugs or dents or anything else seemingly bad. Externally it appears to be in great shape.

I believe necks can be sourced for this, and if so, would this below work? Looks like the same thing, but I guess I'm gonna have to do some measuring to make sure. The hose nipple is spot on. Hopefully the hole sizes are the same. Has anyone had to "re-neck" their radiator? Honestly, I've never seen a neck broken before. Had one spring a leak one time, but not busted stuff.


To note, I have some soldering skills. It is NOT a hugely tough job to do. However, I'd like to take the radiator to a radiator shop and have them clean it and test it, and while it's there, just have them put the neck on it if the radiator is worth saving. Pros are better than me.

Again, like most things, I got an NOS fall back if things can't be fixed...

Bonnewagon said:

It's just a matter of soldering in a new neck. But if you even have a GOOD radiator shop left there, might as well get it cleaned out and checked anyway.

Click to expand...

Exactly. While it visually looks pretty good otherwise, I'd rather have it tested, and if I'm going to do that, just have them clean it up too. Can't hurt and if it does, then I know where it stands.

Staying with the coolant theme for a bit...

I took off the old thermostat housing and thermostat. Interesting thing about the thermostat bolts for an 84-90 Olds 307. If you have electronic cruise control, the driver side bolt is actually a stud. The passenger side is a regular 5/16-18 bolt, 1.25" long. The stud threads into the intake are 1.5" long. The top side of the stud is 5/16-18 x 0.8". Go figure. If you don't have cruise control, you'll need two regular 5/16"-18 bolts, 1.25" long.

GM bolts are p/n 9440181 for the passenger side and driver side without electronic cruise.

Driver side with cruise takes stud GM p/n 22506338 or equivalent.

Coolant Outlet Housing is GM p/n 409037, superseded to 12302551. It has the curved pipe already installed and is made of cast iron.

Gasket is GM p/n 22547855.

Thermostat is 195 AC/Delco unit, stock regular flow for 307. You're on your own for any other temp or style. GM p/n 3051139.

Bolts. You can see the stud is longer than the bolt. And they are through bolts right into the coolant, so you need to coat them with sealer.

Update:

Dropped the radiator off at the local radiator shop. First time I'd ever been there, but the shop has been around for a long time. Does radiator repair/electrical work (rebuilding starters/alternators, etc.)

We jaw-jacked for a while over different cars of his and mine, what needs doing, etc. He said he usually only sees brass type radiators mostly from the 20s - 70s cars, and aluminum ones from the newer cars. Not so much one from the 80s. He said usually people usually just toss the brass and go with the aluminum/plastic replacement, but he seemed a bit excited to give mine a once-over, and told me 3-cores weren't rare, but not all that common in the 80s G-bodies. I learned that Harrison would crimp the necks on at the factory. He showed me a spot that MIGHT be a seepage leak, it may not be, but he said he could plug that single tube if need be. He's going to take the tanks off, rod it, and pressure test after cleaning to make sure. He did caution me that the radiator is 40 years old, so there's always a potential for future leakage, but he's pretty confident he could get it cleaned out, repaired as needed, tested, and put the new filler neck on it. Could leak next month, next year, or next century. Again, I have a backup plan should that be the case. He said they still have brass radiators out there if it blows up. For $175 out the door, I'm not going to gripe.

I'm still putting in a couple of those pellets the factory used in any event. New hoses, "new" radiator one way or another...




Apparently U.S. Radiator has them, but OMG, they're proud as f** of them.