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drain and refill coolant

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Guinn

Guinn

Jedi Warrior
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I started a "simple" job this evening: Drain, flush and refill the coolant in my 78B. What idiot re-designed the coolant system and, better yet, Why? There is no radiator cap, no engine drain plug, no radiator drain plug! I knew it was like that before I started but thought I could out-wit the system and do it all in an hour. Yeah.

I pulled the radiator hose loose at the engine, then pulled the lower hose loose, getting a faceful of Prestone in the process. Replaced the lower hose and tried to pour coolant into the engine at the thermostat housing. Got a cupful in and realized I had to remove the thermostat. Poured a gallon or so of water in, closed it up and ran the engine for a couple of minutes. Opened it back up, drained the water out, repeated above. Water was quite clear, no rust, no crud. I have now refilled the block with Prestone but need to put some in the radiator too.

Is there a better way to fill the radiator other than just up-ending the hose and pouring it in there? Is there a better way to do this whole job? Any help will be appreciated.

Guinn
 
To initially fill the cooling system, I disconnect the upper radiator hose from the thermostat housing and fill the radiator through the hose until coolant starts coming out of the thermostat housing. I then reconnect the hose and finish filling the system through the top of the thermostat housing. I fill the expansion tank about half way. Most cars I usually drain the radiator by removing the lower radiator hose.
 
Thank you, Kimberly. This is basically what I am doing. My B has been modified by a PO so is difficult to do it exactly that way.(Cannot fill through the top of the housing).

Guinn
 
Hi Guinn, take the radiator to a shop and have a filler and drain put on. I see it done all the time in the shops.---Keoke
 
Not this time, Keoke, but it is on the todo list! I just thought I would do it the hard way this once.

Guinn
 
There is an engine drain plug. Passenger's side, near oil pressure line. Its hard to get to and I really wouldn't mess with it though as (I have heard) they are usually clogged up and if used, sometimes start leaking.
 
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