Radiator Leak


Steve777

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Was driving the 94 B4000 tonite when I noticed the temp gauge moving a bit erratically up and down. No signs of overheating so at first I thought it was a wiring or sensor problem. But when I got to my destination in a few miles I checked under the hood. I could smell antifreeze. It was dark, so a bit hard to see even with a light, but the passenger bottom corner of the radiator was wet. Didn't leave a puddle but that seems to be the leak. Filled the now empty reservoir with antifreeze and distilled water and drove home.

At home I did some more checking. Still the only wet spot is the bottom corner of the radiator. I checked the upper hose connection on the rad on that side and it is dry. Also checked the drain spout and it is dry, so I don't think it is the source. Possibly the cap seam on that side but I couldn't see all of it and it seemed dry where I could see it.

So I guess I have two radiator questions for these trucks:

1. Any thoughts on common leak locations on these radiators which match up to these symptoms (passenger side bottom)? Any place else I should look before replacing the radiator?

2. Assuming it is the radiator, looks like two are available, a standard one for manual trannies, and a "heavy duty" one for auto trannies and the HD cooling system. Well I have a manual tranny but I think it also has the HD cooling upgrade (at least the fan fit the HD fan clutch when I replaced it). So which radiator do I get? Is the HD one really HD or does it just add an auto fluid cooler? Any easy measurements one can do to determine which radiator you have?

TIA
 


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swynx

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i know that ive seen a few of these radiators where the ends have seperated enough to make them leak, thats probably what has happened to yours.

as for the radiator im betting the HD is for a/c and an auto cooler. however on rockauto they have 2 and 3 row radiators listed for automatics. i would just measure the width at the top of the radiator, and get the thickest one you can (3 row) i know that ive seen bigger and smaller manual trans radiators. i assume the difference is for the a/c.
 

Steve777

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Thanks swsnx. Took the old rad out and it was the narrow one (1" depth). Not sure if that is a 1, 2, or 3 row unit, but it has always been fine for cooling the engine, so I replaced it with the same. Unfortunately the folks at the local parts stores did not seem to know much about the radiators they were selling. They had the dimensions of the core and inlet/outlet sizes, but not much more (like how many row it was).

Anyway it was a snap to do the swap, and now I just have to see how it all behaves and if there are any lingering issues.
 

swynx

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generally what i would do is get a part number for the part i wanted (how many rows) using rock auto. and take that to them. they dont know any thing more than there computer will tell them. but seeing as how you had a pretty slim radiator before without issues. i dont see why you would have any new issues occur.
 

Steve777

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Would have been a good idea, if I had the time to get a specific part in. But I was in a hurry to get this truck back on the road, so I choose among the available models at the local stores. I would expect that replacing it with the same sized one, should work (hope so). But so far it has been working, so I'm keeping my fingers crossed.
 


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