Greg Mueller

Yesterday I bought a 7x14 cargo trailer and was cruising up I-25 in New Mexico.
I'm betting it was well over 100° up around Socorro.

The truck was not very happy.
The terrain is pretty hilly.
Going up the hills the warning light and dinging bell would go off. Going down the hills the light would go off and then come back on going up the next hill.
The temp gauge was approaching 240° at times.

This morning I checked and the radiator was full.


Guilty admission......I've never done anything to the coolant system and I bought the truck new in '98....... Shame on me.


My plan is to drop the coolant and put new water in it. I ordered some Gunk C2124 Super Heavy Duty Radiator Flush and I will put that in and let it work for a while and then drop that.

Today driving around without the trailer it performed normally, running up to 190° and then back down a way, so it looks like the thermostat is working.

In case the flushing doesn't help I was thinking of just replacing the radiator.
On line it looks like they run $150 or less.

If I have to replace it I need a recommendation for a new radiator (and cap) that is as good as or better than the original. There's so many offered it's hard to know which are good and which are not as good.

Suggestions?

Thanks
Greg

AlpineRAM

Depending on where your crankcase vent is..

it may be sufficient to remove and clean the radiator (and the intercooler, trans cooler) from the outside.
With the stock setup a lot of trucks have the radiators gunked up with oil from the blowby and whatever dirt sticks to it.

Greg Mueller

The oil disperser is on the driver's side back from the front pulley a way.
Everything around it has a nice protective coat of oil and dirt but I felt around and couldn't find any on the radiator or fan shroud.

I finally found the radiator drain and turned it 90° but nothing came out.
I was thinking of shooting some compressed air up it to see if I could dislodge whatever has got it plugged up.

I finally managed to get the bottom radiator hose off where it connects up to the engine (bugger) and emptied everything that way.

What a confused bunch of stuff down there.

I'll try hosing the radiators off with a hose and see what happens.
Glad I'm retired, at least now I have time to monkey with stuff.

AlpineRAM

The petcock on the rad drain needs to be turned and pulled out at the same time, but being plastic and old... I usually recommend to pull the rad hose.

Greg Mueller

How do you get in there with the hose with the intercooler in the way?
From the fan side?

Are there any instructions (pictures maybe?) somewhere for removing the radiator?


PS
Those factory hose clamps are maddening

SIXSLUG

The petcock turns 90 degrees then requires a pull to get it flowing...

Pulling the radiator to clean will be better than trying to blast cold water thru it...

While your system is empty, pull the water pump and inspect the vanes...

"New" radiators are from china and are usually problematic. My lifetimer from Napa in my Tahoe has been replaced TWICE due to solder joints failing...I'm spending a lifetime replacing it....

Just my .02

Greg Mueller

Pulled the radiator and it was not at all dirty.

Went and Simple Greened it and hosed it anyway.
Even though I have flushed it a few times, some nasty greenish-rusty looking thick water type of liquid came out of the bottom hose attachment as we flipped it over.

I am replacing those hose clamps with with some SS hose clamps that you can use a socket on.

We laid it on it's front side and put the radiator cap on and stuck the hose in one side and let it flush out anything that was still in there and then the other.

We are ready to put it back on.

PS
Wish I would have known about "spinning off the fan"

AlpineRAM

Well, the rad needs airflow and flow of water- remove one of them and it won't do it's job.
Since yours seems to look good, and now clean, you seem good to go.

In industrial applications Cummins recommends to replace the radiator cap annually.. how old is yours?

Spinning off the fan- yep, a big timesaver!

Greg Mueller

Yesterday I got and used the GUNK flushing stuff and did the flush.
Got a new thermostat and installed it.
Got a new radiator cap.

Everything was original.....

Can't think of anything else to do other than getting a new radiator.....

VADSLRAM

When you flushed, was it in the reverse direction of the normal flow?
Sometimes a little not to serious gunk will plug up passages and a little pressure backwards will clear it. You should have taken it to a shop when you had it out. Any good shop will have a back flushing setup that uses the cleaner with enough flow and pressure to open up all the tubes.

But with what you did and some fresh coolant you should see a difference.

VADSLRAM

Also check the intercooler / A/C and oil cooler for bugs and road crud. They could be starving airflow to the radiator.

Greg Mueller

The AC unit is new, so probably not that.
It seems to be running a bit cooler now (test drive). The real test will be trying to tow the trailer again.

Puke

Mine was giving me trouble and I replaced the radiator and it fixed it.. HOWEVER,.. my radiator, when I took it out,.. had an awful lot of crud on it.

SIXSLUG

Check the water pump.....

Greg Mueller

What brand/store did you get yours at?