Conditioning/Flushing the cooling system..

[GHall]

Today I was doing a once over, checkin nuts and bolts, greasing things, checking fluids, putting anti-seize on little fasteners that were gettin rusty and I noticed the coolant surge tank had kinda a rusty film in it. I read a few threads about what kind of flush additives to use, CLR, an acid bath and cummins has one apparently. I'm gonna flush it 4-5 times and change the filter several times in the first 100 or so hrs. I just wanted to know what y'all figured to be the best cooling system conditioner and flushing agent?

Thanks!!

 

[Artisan]

Here is what I did.

On either side of the radiator at the bottom are two plugs, I pulled
them and installed Butterfly valves w/ caps.

ALL radiator hoses were pulled down to the individual piece.
Everything washed and examined.

The radiator was filled and let to drop flush 5 times w/o hoses.
Just hold your hand over the bottom.

There are 2 vent hoses on top, one from the puke tank to the rad
and one from the puke tank to the header. I replaced them, the short
one gets clogged.

I hooked up a variety of fittings to a garden hose and back flushed and
forward flushed and flushe the daylights out of the puke tank (lots
of crap in it) . I flushed the tranny cooler, and the oil cooler is it?

You name it I flaushed the daylights out of it. I even pulled the
trapazoidal engine access panel, one of two, the front one to
look at the lower parts of the blocks water jacket and it was CLEAN.

The rad t fitting and pipe were glass bead blasted and painted and
put back in place and UI topped it off w/ 24 quarts of Ethyl Glycol
and water.

Oh, I replaced all heater hoses and the heater shut off valves.
I flushed the heater coil and a LOT of crap came out of it. All
flushing was done w/ a high volumn hose and fittings and valves
so as ot be sure I flushed everything as good as I could.

I highly recommend these procedures. I bet ya I flushed out
2 quarts of rust-muck...there was a LOT. Now it is as new...

OH, i also extended the heater hose away from the exhaust manafold
with a 4" brass nipple I think it was. I will try to remember to take a
couple a pics of my mods, they work WELL.

 

[searls84]

I run DCA-4 additive in my truck. The NHC 250 is very prone to electrolysis which will lead to eventual coolant in the oil. The DCA-4 combats that. You can pick it up at most any semi truck service center for about 6-8$ a bottle. I used about 3 bottles to get the right level in my coolant. Also pick up a couple of coolant test strips, helps you adjust conditioner levels and kind of let you know what shape your coolant is in.

 

[GHall]

Pics would be great Artisan, thanks for the step by step! Searls, thanks for the tip, will do!

 

[jw4x4]

I use commercial truck coolant which contains SCA (supplemental coolant additives). A must for engines with cylinder liners. As suggested by searls84, test strips are very useful to maintain the proper formula. Too much is just as bad as not enough.

 

[Artisan]

Pics as requested.

I replaced the rad/surge tank cap new as well.
There was a valve where the mystery deal is. Anyone know
what it is / was for?

The surge tank to rad hose was made new AND 14" longer.
It allows a guy to lay it in the engine compartment a 'lot nicer.

The hot water heater valve extension is mandatory in my book.
That hose is WAY to close to the exhaust manifold.
The hot water heater valves are good to have working, in
the summer shut them OFF, or if you get a heater coil
leak shut them off and keep on driving!

All hose clamps were glass bead blasted and lubed.
Sure do wish I had ALL BLUE Rad hoses! Anyone have
piles of extras? HA! Yep kinda anal I can be.

The radiatior drain down valves are biotchin' lil Italian
Butterfly valves. Way nicer than ball valves and they
were full port too! I think McMaster has them.

 

[Artisan]

DOH!

How could I forget!

I pulled the thermostat and replaced it.
I used no gasket but I did use a sealant.

The thermostat has a SEAL it slides in and out of
and I replaced it as well. The bottom of a rattle
spray paint can worked WELL to seat the new seal.

 

[GHall]

Wow! Thank you sir!

 

[hotbox]

Nice pics! Found a puddle under my 5ton this morning. Traced it back to the top heater petcock. Closed both petcocks, but still dripping a little. Added 1.5 gallons of coolant to the expansion tank. Is the coolant system supposed to be pressured when cold? I think I will use your tips and extend the valve away from the exhaust heat.

 

[jonesal]

Artisan, I can tell a plumber a mile away. Nice brass fittings, sealant tape, everything just so. Nice work.

Al Jones
'84 M923

 

[jarhead1086]

I have been unintentionally flushing my system with expensive Fleet Charge SCA coolant due to a bad hose clamp on the big upper radiator hose and also a bad bite on the lower heater valve. These replacement valves look much nicer and 90 degree intersections too. I need to get mine home 300 more miles and then pull the radiator for rework and replace hoses and clamps in my sterile garage. I may pony up for matching hoses to go with those brass fittings. Thanks for sharing the tips. The only question I have is what you all think of stop leak. Would you put it in a newly reworked radiator and flushed system like Uncle Sam does? In the dark during a snow storm it looked like oil in my coolant.