Coolant in motor

[Robert C.]

If you drain and flush the radiator of coolent approx. how much coolant/water is left inside the motor? Any way to get it all purged without removing the block plugs?

[Wayne M.]

Re: Coolant in motor

Bob --- If you drain the radiator, the coolant level in the block is lowered only to the bottom of the 2 holes in the waterpump on each side of the timing cover. Roughly 1/3 of the total fluid is still in the engine (1/6 on each side). If your block plugs are frozen (as most are), you can remove a lower rear head bolt (outside the valve cover) and siphon it out with a small hose as low as it will go). Do this both sides of the block.

[Joe L.]

Re: Coolant in motor

Bob------

Also, you can reverse flush your system using a reverse flush kit available from most auto stores for a nominal cost. Then, after you finish flushing thoroughly so that the flushing water runs clear, drain the system as far as you can with the radiator drain. Next, add enough full strength coolant required to get your system to the 50-60% range. Last, top off with water to fill the system. That's the easiset way to do it.

Of course, when you use this method it pretty much precludes you from using deionized or distilled water. However, if you have a relatively good municipal water supply with reasonable TDS (e.g. less than 100 ppm, or so), the benefit of distilled or deionized water is de minimis.

[Jim T.]

Re: Coolant in motor

About a year ago I removed the block drain plugs from my original owner 68 327/350 L79 (really my wifes car). Reason I had never removed the plugs before was that they are hidden behind the spark plug wire shields. Took the starter off and removed the shields and drain plugs. You would think that after 31 years it would present problem in getting the plugs out. They both came out so easy, still can't believe I had such good luck. Anyway I measured the water that drained from each side and I believe it was about a quart on each side. I installed DEX-COOL mainly because I wanted to wait five years to change coolant again. So far everything is okay.

[Duke W.]

Re: Coolant in motor

Jim - Texaco does not officially recommend the five year interval for engines that have previously had conventional coolant. Conventional inhibitor packages leave salts behind which dissolve back into solution and reduce the life of the organic corrosion inhibitor package. They have no specific data on this, but their technical people suggested to me that the first load of Dexcool should be changed at two years, and thereafter, every four. Of course, this is dependent on thoroughly flushing the old coolant out before switching to Dexcool. I think that most fleet testing has been done with new engines initially filled with Dexcool, and they just don't have much data on older vehicles that have run with conventional coolants for a long time.

Even if you conclude that Dexcool has no extended life properties and change it every two years, you will still benefit from its superior corrosion protection over conventional coolants.

Duke

[Duke W.]

P,S.

A couple of years ago I helped a neighbor switch to Dexcool on his '77 L-48. The block plugs came out with little problem, but the expected waterfall of coolant did not come spraying out. Turns out the bottom of the block was plugged with deposits, and I was able to clear drain passages with a dental pick. I figure the block plugs had never been removed. BTW, I recall we had this Dexcool, block plug, dental pick discussion two or three months ago.

Duke

[motorman]

Re: P,S.

i have seen when draining the block plugs that the coolent stops and you think that that side is empty but it turns out that a lump of crud just plugged up the hole, so make sure that you poke around in the drain hole after the coolent stops flowing.

[Jeff]

And jack up each side of the car to tip it and...

...make a little wand extension out of an old air nozzle tip for your wet/dry shop vac and suck out the remaining goobna...

JP