My 1989 Ford Crown Victoria has apparently had the water heater core fail. The engine hasn't overheated but after running the vehicle for a period of time around town, shutting it off to have lunch at a restaurant to give you an idea of the time period... the inside of the windshield is fogged over.

The heater core has been replaced once before and I don't wish to travel that road again so what I decided to do was to use something called Bars-Leak Head Gasket Repair. I've seen this stuff seal cracked blocks in the past so I thought it would surely seal a leak in a heater core.

I unsrewed and removed the drain plug from the radiator and stuck a rubber tipped hose into the fill area to flush everything out... then let it drain completely. As instructed, I mixed the Bars-Leak with three (3) quarts of warm water and proceeded to pour that mixture into the radiator, expecting that I would naturally need to top it off with a good amount of water.

The radiator would not take even the three full (3) quart mixture. Warming the engine up so that the heater pushed out hot air did not cause the water level to drop. Nothing in the Bars-Leak instructions nor the vehicles owner manual says anything about other engine block drains.

I've run the engine long enough that if it was going to overheat, it would have done so but it does not. The Bars-Leak mixture... I have about one quart left whereas there is no way the radiator will accept it let alone additional water.

Obviously I am overlooking something.... confused!

 

Joe something I have found and that is the quality of the heater core from Ford as compared to an aftermarket core is like night and day. The imported cores are considerably cheaper, but then again you get what you pay for. Cheap heater cores do not last nearly as long as an OEM core.

Once the engine cools down and the air has a chance to get to the top the level WILL drop !

 

Hanky.... Since entering my post, one stage of the Bars-Leak procedure that I reached is to run the engine for 20 minutes, then to let it cool down for one hour, after which to open the radiator drain plug to drain the system again. The next step is to leave the radiator cap off along with the drain plug being open... this is to last 12 to 24 hours. I'll let it set for 12 hours.

Before I drained the radiator (after sitting a hour), the fluid level was right at the top of the radiator... hadn't dropped a half inch. It's like the water isn't draining out of the block. However, I would think that the radiator alone would hold more than two quarts.

Would pressurizing the radiator with say 15 psi of air do anything... force water out?

 

It should.
With the radiator drain open and the cap off at the top of the radiator it should run out.
If it doesn't , could mean the radiator is plugged and the air can't get into the radiator and replace the draining coolant. could also explain why the level has not gone down as would usually happen. There could be more stop leak in there than in the store . Forcing air under pressure may or may not open it up . but I wouldn't go over the usual 15 lbs. pressure as shown on the cap since you could blow a hose or something else. Have you considered trying a radiator flush. You need to be careful there too because you could clean the stop leak from other areas and create a radiator that would look like a shower nozzle.

There is the possibility you may have to end up replacing the radiator too. If you get some of the coolant out can you see the coolant tubes in the top of the radiator? If they appear full of calcium and white corrosion growth (called solder bloom) the coolant can't flow through them.

 

Hanky.... Friday morning, I'll get back to that project right shortly and look for the "solder bloom" you mention. If the cooling system is really clogged, it's strange that the vehicle doesn't overheat. Really got me puzzled.

Other than the heater core years ago replaced by a shop in the area, This vehicle has never had a leakage problem.

Normally, wouldn't the block drain out thru its bottom hose into the radiator to the drain plug? That's always been the case with my other vehicles thru the years.

Would you suggest that I remove the bottom hose from the radiator to see if the block empties via that route?

Do you have a preference in the brand of radiator flush?

 

Keep in mind that the lower hose goes from the low position of the radiator UP to the outlet of the water pump and that is much higher than the lower part of the hose. Therefore, the block will only drain to the position of the water pump and not completely.
No preference with any type flush except a regular reverse flush at a radiator shop.
A little curiosity goin here, if you remove the lower hose at the radiator and let it drain, does any liquid come out if you add it to the radiator? If so, it should also come out when you open petcock or drain plug. I'm just as puzzled as you when you drained the radiator and was able to add only 2-3 qts. That rad should hold at least a gallon.

 

I wasn't aware that the bottom hose ended up being that high (never had it off). I wonder how one is supposed to empty the block of liquid so as to be able to fill with the correct amount of anti freeze?

Letting the vehicle sit 12 hours with the drain open and the cap off... It only took 2 1/2 quarts of water to fill the radiator. Something's clogged bad somewhere I'm thinking.

At my age (81) although I'm in good condition, perhaps this is a little bigger problem than I should undertake. I think I'll just put it in the shop for a thorough cooling system flush as you mention above. I'll let you know how I make out.

 

Joe , I think that's a good move.
If it helps answer a question, there are small pipe plugs under each side of the V block engines about midstream. these plugs can usually be removed to drain the block. A good portion of the time sediment settles near them and after the plug is removed we have to poke a piece of wire in there to open the drain. If you decide to have a shop flush the cooling system ask them if they plan to remove those plugs and allow the sediment to come out of there. A good flush would include that. Glad you are in good shape to tackle as much as you have !!

 

Hanky... I inquired of a few shops in the area and they don't want to be bothered. There are many other of course and I may contact them. However.......

The pipe fitting drain plugs you speak of rang a bell and I thought back to the early (very early) Ford V8 engines which had those pipe fittings to remove to avoid a Winter time cracked block. Many vehicles back then in pop's salvage yard in NJ didn't have anti freeze so the water had to be drained.

In this 1989 Ford 302 V8, would that be just one (1) drain plug on each side?

 

I hope so.
If you don't mind my asking, what part of NJ ?