question about replacing radiator

[duanel]

On my 73 blazer I need to replace the radiator, it seems gm used 6 different sizes of radiators I understand that to replace a 3 row with a 4 you need the wider support pads and to mod the top mount for the wider rad. But my question is there any problem putting a 19 inch core in a rig that originally had a 17 inch core.

 

[dyeager535]

Yes, the upper bracket(s) are different. I assume the '73-80 used a one piece drop plate to hold the upper portion of the radiator in.

'81-87(91) used a small bracket on either end of the radiator, and there were two different ones for the 17 vs 19" radiators. Of course, big blocks (diesel too?) used a larger one piece steel plate.

 

[4X4HIGH]

Yes, the upper bracket(s) are different. I assume the '73-80 used a one piece drop plate to hold the upper portion of the radiator in.

'81-87(91) used a small bracket on either end of the radiator, and there were two different ones for the 17 vs 19" radiators. Of course, big blocks (diesel too?) used a larger one piece steel plate.

My 89 blazer stock has a full 1 piece top plate with the 19" tall radiator.

 

[dyeager535]

Is it a 3 core?

Guess maybe it's '81-87 if not then!

 

['79shortbox]

On my 79 I run the 19" tall 4 core radiator with a top plate from LMC. The plate and bushings aren't that expensive but they were a pain to mount and they don't fit as tight as I would like, but they do let me have a big radiator.

 

[4X4HIGH]

Is it a 3 core?

Guess maybe it's '81-87 if not then!

Mine is a stock 3 row 19" tall with a 1 piece plate.

 

[duanel]

thanks for the replies, so what I am thinking is to go to pull and save get the rad, pads, top plate, mounts, out of a 73 to 80 truck. sub or blazer (unfortunatly they don't have a blazer with a rad right now) and I should be able to get it to work regardless of the size

 

[pauly383]

I'm in a pickle myself here , I want to put my 83 radiator which is less than 2 years old into my "new" 73-75 truggy .

Well my 83 has a tall radiator , with a bracket over the top on each side , and the plate is actually part of the fan shroud .

The truggy has holes for the short radiator , but nothing on the top . And to make it worse , the radiator is too tall for a short mount , but comes up short so I can't just drill holes and use my over the top brackets . I would have an inch between the brackets and the top of the radiator if I tried

 

[dyeager535]

What about the holes on that lip of the core support? Didn't the "tall" 73-80 radiators use a full plate that was across the top?

I know the radiator in my dads '81 was installed in a '73-80 K5, (it was my buddies) and it's a 4 core tall radiator.

 

[pauly383]

Been doing research this morning at the parts houses , there are many different radiators out there :

1975 with a 350 , only came 17 inch . 1975 with a 400 came 19 and 1/4 inch . Thats it .

1983 with a 305 , depending on setup ( auto/manual ) could be 17 , 17 and 1/2 , 19 , or 19 1/4 inch .

I've never measured mine ( on the 83 ) , just always got the 3 core that takes over the top plate on each side with the middle shelf part of the fan shroud .

I didn't look at diesels , since they were 34 inches wide .

I have several plates , but not the one I need , so I may cut and drill , its a truggy . I really wanted plug and play .

 

[dyeager535]

I find it hard to believe that GM used more than two radiator sizes with a 305 in the same year. Diesels and big blocks yes, not the same displacement motor.

Only reason I say this is because I am only aware of two height brackets for the 2-3 core radiators 1981-91, which are either 17" (stepped down) or 19", which are essentially flat. I've never heard of a bracket being 1/4" too short.

Another thing I can check my parts manual on tonight if you are interested. I *think* by '81 GM only had 4 radiator supports...short, tall, 4 core, and wide 4 core. I'd be inclined to believe the aftermarket catalogs are wrong. But wait and see what others think.

Napa I see shows a 17, 17.25, or 19" radiator as fitting a 1983 K5 w/305, I think there are only two. GM wouldn't have used a radiator a 1/2" taller when it would require more components.

And more...LMC lists the same three, but lists the 17.25" as '85+ only. There is more if anyone wants to play with the LMC catalog, but the end result appears to be a 19" radiator is a 19" radiator. They list the same 19" part number for '73 and '91.

 

[pauly383]

I will make something work , and post up when I'm done . Probably Friday night .

 

[dyeager535]

Shouldn't be this complex lol.