I noticed that **************.com sells a kit for reinforcing the radiator neck. It looks like a good idea, but the price is pretty steep for a piece of copper pipe and some epoxy.

Anyone know what size copper pipe would work? By my measurement, the OD of a 1" pipe is a little too large.

You can get some emery cloth and sand down the copper tube until it's a snug fit.

I used 1" copper pipe and with the epoxy on it I was able to get it to slide right in. I have run into trouble finding an epoxy that is safe for immersion in coolant. My neck broke off about 1/2" from the end, so I tried to epoxy the piece back on with the copper sleeve - it only lasted 6 months with the epoxy I used, I think I will do a little more shopping for epoxies - I'm open to suggestions if anyone has a good product!

Repaired broken top neck by glueing two halfs of copper pipe over neck.
Used epoxy called JB Weld. Hose clamped (2) without hose overnight, sanded smooth. Then used radiator for a year, 15,000 miles with no problem.

That's an idea. Maybe I could cut the pipe lengthwise and squeeze it down a bit to reduce the OD.

I must be one of the lucky people....I removed my radiator at 230k and found it to be original. It was mostly clear inside but the fins were dented and filthy....so I opted to just replace it. (It fulfilled its duty running for 23.5 years with no incident) Put in a new Behr $$$ radiator....lowered my temps to 82C at operating temp....never, ever goes above 85 even when its ultra hot outside. The neck on the original radiator was still perfectly solid, no signs of cracking or weakness.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

I work at a Freightliner assembly plant in Cleveland NC. They use Behr radiators, same basic construction with plastic top and bottom sections. In each one of them, if you look inside the hose connections, you'll see a piece of copper pipe glued inside, straight from the vendor.

__________________
Just say "NO" to Ethanol - Drive Diesel

Mitchell Oates
Mooresville, NC
'87 300D 212K miles
'87 300D 151K miles - R.I.P. 12/08
'05 Jeep Liberty CRD 67K miles
Grumpy Old Diesel Owners Club

I checked my new Behr when I got it, had no copper inside it, but it does look a little thicker/more ruggedly constructed than the old one.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Epoxys are great adhesives but as a general rule they dont like heat. You can soften any epoxy with heat. I think a polyurethane adhesive would hold up better. Possibly gorilla glue, Might be worth a try.

85 300td
85 300d
83 300d

JBweld?

I don't know what year or model your car is, but if it's over 20 years old and has the original radiator, you may just want to go ahead and replace it now with a new Behr with the reinforced neck already installed from the factory.

__________________
'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.

Replacing the radiator is precisely what I am hoping to avoid!!!
But when that time comes, the new radiator is probably going to be a Nissens instead of a Behr.

For a passenger car radiator, that might be sufficient. The radiators I was referring to are for Class 8 semi's, 18 wheelers. 2 1/2" hose connections, large enough that it takes 2 people to pick one up, close to 3 ft wide by 3 ft tall.

The radiators for the EPA '07 engines are even larger. Laid flat on the floor, they look big enough to put a mattress over and use for a bed frame!

__________________
Just say "NO" to Ethanol - Drive Diesel

Mitchell Oates
Mooresville, NC
'87 300D 212K miles
'87 300D 151K miles - R.I.P. 12/08
'05 Jeep Liberty CRD 67K miles
Grumpy Old Diesel Owners Club

jbweld.net

I wound up machining down a piece of 1" copper pipe. Reduced the OD from 1.30 to 1.175 so that it had a slight interference fit. Tapped it in without using any type of adhesive. Now I just hope the copper pipe does not expand too much when it gets hot and cause more problems than it solves!!!