Champion radiator difficulties

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

AuroraGirl

Full Access Member
Joined
Sep 8, 2019
Posts
9,122
Reaction score
6,038
Location
Northern Wisconsin
First Name
Taylor
Truck Year
1978, 1980
Truck Model
K10, K25
Engine Size
400(?), 350
Yes, I found some studs that fit. The serpentine was a GM kit from Summit that included new: water pump, PS pump, A/C compressor and alternator plus all hardware/brackets.
I added reverse fan/clutch. I may look into adding fan spacer with long bolts instead.
The reason I didnt suggest fan spacer is both that 1) that fan and clutch are already quite a bit far out there, and most spacers are longer than what you need to change. Im not sure if it will be a big deal or not but if you can find a spacer to do that amount that should work
 

dusterdude

Full Access Member
Joined
Oct 7, 2020
Posts
322
Reaction score
331
Location
US
First Name
mark
Truck Year
1985
Truck Model
gmc c15
Engine Size
305
mcarlo,radiator dropped in fine.bottom hose fits fine.top hose is too small.did you find a hose that will fit?
 

mcarlo86

Full Access Member
Joined
May 17, 2019
Posts
530
Reaction score
926
Location
ND
First Name
Brian
Truck Year
1990
Truck Model
Suburban
Engine Size
350
mcarlo,radiator dropped in fine.bottom hose fits fine.top hose is too small.did you find a hose that will fit?
Yes, I ended up using a flex hose that had the correct size ends.
 

dusterdude

Full Access Member
Joined
Oct 7, 2020
Posts
322
Reaction score
331
Location
US
First Name
mark
Truck Year
1985
Truck Model
gmc c15
Engine Size
305
Groovy
 

75gmck25

Full Access Member
Joined
Oct 13, 2016
Posts
2,018
Reaction score
1,811
Location
Northern Virginia
First Name
Bruce
Truck Year
1975
Truck Model
K25 Camper Special TH350 NP203
Engine Size
5.7
If you want a radiator to be “direct fit” I suggest looking up your truck on RockAuto to see the various options for that year. Then measure and match your current radiator core with one of the sizes you found. The size should also have a number, like CU161, CU730, and that is the number you need to match. Don’t get confused by buying a radiator advertised as 3 row or 4 row, or for a big block or small block. The product numbers or core size are what you should match, not a general description.

IIRC, radiators are sized by the core (the finned area), not the overall radiator size, and the brackets and tanks increase the total size. The stock radiator bracket should hold and grab the radiator properly if you have the right total size. If you switch to a different CU number you will need the rubber saddles and brackets to match that size of radiator if you want it to be held properly.
 

SirRobyn0

Full Access Member
Joined
Dec 6, 2019
Posts
6,698
Reaction score
11,151
Location
In the woods in Western Washington
First Name
Rob
Truck Year
1984
Truck Model
C20
Engine Size
305
Also there are some radiators made for these trucks that have multi-sized necks on the upper hose, so it had the smaller size and then steps up to the larger size. Also @dusterdude if you don't want a flex hose play try looking up a GMT-400 hose, or even just playing around with the year some. There was a smaller and larger upper hose used factory.
 

dusterdude

Full Access Member
Joined
Oct 7, 2020
Posts
322
Reaction score
331
Location
US
First Name
mark
Truck Year
1985
Truck Model
gmc c15
Engine Size
305
I found out the upper hose is supposed to have a 1 1/2 in opening as does the rad.my old gm rad has a 1 1/4 opening,my hose which was clamped on the old rad for so long has set in that sizing.im going to buy a new hose and see how that goes.i will let ya'll know later this week.
 

Latest posts

Forum statistics

Threads
41,857
Posts
903,629
Members
33,370
Latest member
mitchell1128
Top