8N Engine Block Coolant Drain

The only way you can really do a good cleaning of the radiator is to remove it and have it professionally rodded out to remove the built up crud in the flues. Flushing it by draining it and pouring water through it does nothing except maybe clear up the coolant color because the stuff that is detrimental to the cooling is stuck in the top of the flue openings. The coolant enters the top of the radiator and so do the particles that are in the coolant but the crud stop in the openings of the top of the flues and will not go down.

There is one thing you can do that will move some of the crud up and out the top of the radiator and that is to take the clamp off the bottom hose and open the hose enough to get the end of an air blow gun into the hose and start flooding the radiator with lots of water at the top. Pulse the air gun just enough to force the water up and out the top of the radiator. Best to have your storm suit on because it will go everywhere.

Be carefull that you don't overpressurize the radiator which is easy to do when you are using 100 PSI air pressure. Just pulse it enough to shoot the water up out the top of the radiator.

Draining the block is about the same story. That crud that is sitting in the bottom of the block is not going to move by opening the drain cock or removing it. The only way to really get most of the crud out of the block without tearing it completely down and having it boiled out is to remove the two end welsh (Freeze) plugs and do the same thing with lots of water and air. That will get most of it out.

Wear old clothes! They won't be any good when you get done.

Zane

Fairly simple? Depends. The originals were made of brass and could strip easily. Problem is, sometimes these drain cocks have been left in so long they are almost fused to the block, and can be tricky to remove - take care. Here is three original drain cocks I recieved off ebay that I refirbished, getting ready to bring my 48 8N trailer queen in to get here closer to original (I won't call it a true restoration yet). If you look close, you can see two have a "B" stamped in them (block), and one had a "R" stamped in it (radiator).

If you aren't a stickler for originality, you can get standard modern drain cocks at any decent hardware store.

Good luck,
Dan

As far as I know, these are just regular engine/radiator drains; 1/4" pipe, I think.

They are frequently removed from the block by desperate starter remover guys to gain additional angle purchase for starter removal. I didn't find that necessary when I removed my starter; of course I know how to hold my tongue "juss-sew" (grin)..... ...Dell