Cooling issue

The radiator can be stopped up and still flow. As old as it is it should have been cleaned a couple times by now.

Have you bled the extra air out of the radiator? Put the heater on high while you idle the motor with the radiator cap off. Once hot air is blowing out the heating ducts it means the air is out of the system. If you do that and you still have overheating problems I would suggest getting a block tester and pressurizing the system to make sure that coolant isn't being lost through a small crack somewhere.

Sorry the cap didn't take care of the issue. But you'll need that if you end up getting a new radiator.

Yea I've done all the bleeding and whatnot. I haven't gotten it tested yet. But I'll probably go do that soon. Gonna be busy with work until Friday

Honestly getting the original radiator tested would just be wasting time.Just buy a new radiator and I would also update the waterpump at the same time if it were mine.The time you will save and headaches will soon be history just by replacing well 20+ yr old components.I still would do a coolant flush out after the fact as the heater core builds up debris as well.

Hmm you're right. I already did a flush tho. With distilled and everything. So I guess a radiator and pump is the best way to go

Where did you buy the Murray rad? Can you please verify if it is actually 2 rows? I have been thinking of getting a B2600 rad just because all the ones I have seen aftermarket are 2 rows (but they are 3" wider so it'll require custom mounts) I guess possibly the extra bit of surface area might help too - I don't have a cooling issue now, but summer's coming!

You say that rad is now a 2 row aluminum / plastic tanks?

Reason I ask is they still list it as a copper/brass.

The O'Reilly/Murray radiator is all-aluminum, no plastic crimped-on caps. The first one I got from O'Reilly with that part number (about 4 years ago) WAS an all-copper and brass unit which was 100% bolt-in, which I really liked. However, that developed a leak at a bottom weld after about a year, and the replacement with that part number was the all-aluminum one, which I still had.

Since my B2200 is 5-speed, I did have to drill four holes in the radiator mounts for the fan shroud, not a big deal, photos show this in my rebuild thread below, with colored arrows.
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Yes, these are true 2-row, fit in the same frame as the 1-row. When I compared v. the 1-row, it was really apparent that the extra space just left "open" in the 1-row now had cooling stuff. I think I posted comparison photos somewhere in Mazdatrucking.com, but don't know for sure if that was before that site "crash" when stuff was lost.
Here's the Murray radiator. Mounting holes on front side are fine.


Here's the fan shroud side, on a 1-row there is non-used space on this side. The outlets for ATF are simply not used on a 5-speed truck.


If you want copper/brass 2-row, see if the Autozone 2-row is really copper/brass. If you order in the store (AutoZone or O'Reilly), and you don't like what arrives, you simply don't pay/get your refund.

That aluminum rad is nice looking. Understand that if you change to some rad that is not the factory style you will have to make new mounts. Also understand that a cross flow cools much better than a down flow.

Speedwaymotors.com sells several different sized cross flow rads that can be mounted in the B series.

However, if you are going to get a new one the aluminum one above is a nice choice. If you have it flushed once a year it should never get stopped up.

cusser, it is a direct bolt in tho right?