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Tips
Tips

Coolant Loss

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Another possibility would be to do a leakage test on every cylinder and see if bubbles showed in the radiator.

The leakage testers at Harbor Freight are pretty inexpensive.

Really all you'd need to do is make a pressure hose with an air fitting at one end and a spark plug end on the other end--then pressurize each cylinder to, say 150 lbs at tdc, then observe whether there were bubbles in the rad.
 
steveg said:
Another possibility would be to do a leakage test on every cylinder and see if bubbles showed in the radiator.

The leakage testers at Harbor Freight are pretty inexpensive.

Really all you'd need to do is make a pressure hose with an air fitting at one end and a spark plug end on the other end--then pressurize each cylinder to, say 150 lbs at tdc, then observe whether there were bubbles in the rad.
Click to expand...
Do the above test when the engine is <span style="font-style: italic">stinking hot</span>, so as to replicate the operatong conditions.

Make it a point to not burn yourself in the process (especially removing the radiator cap).
 
I used to have a similar probem with my BJ 8 and bot a coolant recovery bottle that I did not really expect to work but it did and have had no problems since (have owned the car for 24 years).
 
I also added a small coolant recovery bottle, that seems to work well. I placed mine under the right front fender sort of next to the heater blower.
 
Recovery tank is always a good idea.

At a recent British car show, I managed to get a NOS Spridget (brass) overflow/recovery tank. Now I need to get my priorities straight and blast/paint a well-used bracket so I can mount the thing.

I'm still unsure of what cap to put on the original radiator; what did you guys use? It has to allow siphoning the coolant back into the radiator during the cooling down process.
 
I used the 7 lb cap with the correct length that I had previous to installing the recovery tank (E4 printed on the top of the cap).
 
Hi Randy,
The NAPA - Balkamp #703-1411 7 lb. cap works well. It is the correct long reach type, has a good top seal, a good bottom pressure seal, & a one way valve to permit coolant to be drawn back into the radiator. Some caps don't have a good top seal. The spring brass types come to mind.

The coolant recovery bottle must be freely vented to atmosphere.
D
 
Dave Russell said:
Hi Randy,
<span style="font-weight: bold">The NAPA - Balkamp #703-1411 7 lb. cap </span>works well. It is the correct long reach type, has a good top seal, a good bottom pressure seal, & a one way valve to permit coolant to be drawn back into the radiator. Some caps don't have a good top seal. The spring brass types come to mind.

The coolant recovery bottle must be freely vented to atmosphere.
D
Click to expand...
Outstanding! Now I know it will work :wink:

The Spridget tank doesn't freely vent though, so I'll have to do some surgery on the cap for it. I like that tank because I can polish the brass, and it has a genuine siphon tube. Also, it won't look out of place in a fifty (50) year-old car.

Edit: Woo Hoo, local NAPA has two (2) in stock!
 
I finally found the correct thermostat from BCS a few years ago. It's not cheap, but it does work better than the aftermarkets.
Patrick
 
For those of you still following my sad story----water pump replaced and I still have exactly the same problem. So after all of the actions taken so far, which I won't repeat (they're in the posts above) the next step is inspection and correcting anything wrong with the head and changing the head gasket.

Any suggestions about what else I might want to do or have done while the head is off?
 
Art,
Did you try running it with the thermostat removed to eliminate any possible problem with it ?
( not all the time, just for a test for all of you that will jump in and say that you should use a thermostat ).
..... If it turns out to be a head gasket, you should ask for a full refund and explanation from the person who checked your coolant for combustion byproducts and found nothing.
Ed
 
Art

You need something in the thermostat housing, I had the same problem when I first bought mine - losing coolant but not to the same extent, and found the thermostat to be missing. I put one in and no problems since, coolant level about half inch above the core.

The race guys do leave them out but substitute the thermostat with a disc with a hole in it to restrict the flow.

Are the airways through the core clear of dead flies, cats stray dogs and people? How is your temperature ?

For a quick check on the thermostat, open up the radiator cap and view the flow in the head of the radiator at 4000 revs If you have the equivelant of white water rafting flows then this could be an indicator that all is not well with the stat.

Bob
 
ArtQ said:
Any suggestions about what else I might want to do or have done while the head is off?
Click to expand...

Art,
In spite of your earlier statement:
"I have had the system checked (chemical and pressure) and I do not have a head gasket problem or cracked block."

You do have all the signs of combustion pressure leaking into the cooling system.

While the head is removed, check both head & block surfaces for flat within 0.002" & correct if needed. A perfect time to also have head & block checked for cracks.

Replace head studs & nuts with new. Clean all stud holes in the block with a tap & chamfer the tops of the holes. Use sealer as needed on any tapped block holes that extend into the water jackets. Actually sealer on the blind holes also, won't hurt anything, just make sure that the sealer doesn't create a hydraulic lock as the studs are screwed in.
D
 
here's a exert from a earlier post
in 1972 the head of vehicle maintenance for the silicon valley taught a class.
a 1/2 inch of coolant in the tank, just enough to cover the tubes. when the coolant heats it will have room to expand. if you are spitting out coolant the pressure can far exceed the cooling system's rating. the tank is for expansion. air can escape from the tank much faster than liquid. the more coolant in the system the longer it takes to cool down. When i bought HER XKE it ran 240 normal driving the last owner used all antifreeze, no water. antifreeze is not a good coolant, water it a good coolant. the first equipment sent to the Alaskan pipe line over heated in sub zero weather, they had been filled with pure antifreeze. he also said not to use flex-fans at higher rpm the fan flattens to reduce drag if you pulling a hill at slow speed the fan is now blocking the needed air flow

before you get all greasy,
to check to see if the thermostat is closed and then opening at the right temp. and see if the pump is pumping. start it cold with the water level at the top of the tubes, look in the radiator tank when it gets warm you should see the water pumping out the upper hose inlet. i use a meat thermometer to check it. if it's too hot the thermostat might be in upside down. if that all looks good and it still over heats get the good block sealer about $7 the instructions will tell you how to put it in,,,, after you run it for ?? minuets, let it cool, then drain the system and let it dry over night. if it stops over heating the block sealer sealed a bad head gasket or a cracked head. all head gaskets leak !
I was a mild mannered bodyman until i started driving vegi oil burning VW diesels now I'm a head gasket ex-spurt ....hope I've helped you i know how frustrating it can be to work on your own car.
 
The car is reportedly losing more than a gallon at a time. The coolant expansion on a typical Big Healey is a little less than one quart under 7 psi pressure. Normal expansion no where near accounts for this large coolant loss.

the lost coolant has to be replaced or displaced by "something" - either air, combustion gasses, or?

The end result of "block sealers" is to coat the entire inside of the cooling system with a heat insulator & partially plug the water passages. Not a good long term solution.
D
 
Dave Russell said:
The car is reportedly losing more than a gallon at a time. The coolant expansion on a typical Big Healey is a little less than one quart under 7 psi pressure. Normal expansion no where near accounts for this large coolant loss.

the lost coolant has to be replaced or displaced by "something" - either air, combustion gasses, or?

The end result of "block sealers" is to coat the entire inside of the cooling system with a heat insulator & partially plug the water passages. Not a good long term solution.
D
Click to expand...

I agree with you Dave, "not a good long term solution" on a car engine, but when I owned a V12 XJS several years ago and it called out for a couple of packets of "Bars Leak" on coolant changes. Semi trucks use the sealers quite often.
Patrick
 
K&W Nanotechnology is new since May of 2006, I’m not talking about the old block sealer.
the radiator tank has 3 qt's of expansion room and on top of that it spits out 1 gallon that's nearly 2 gallons that isn't in the engine and it tests ok for combustion gases. That's a big problem for a engine that tests OK.
This is EZ. take the thermostat out. put just enough water in it to cover the tops of the tubes start it and look for the water pump circulating the water in the radiator tank, if everything looks good take it for a drive and see if you duplicate the symptom. if it's OK jump for joy. If it over heats, you can pull one spark plug wire off and drive it do this 6 times see if witch one stops the over heating. if you chose to use the block sealer you will be leaving that plug wire off during the treatment. Or you can pull the head and take a good look at the head gasket around that hole. it should be a uniform color, no darker spots. if it looks good to you, get a second opinion,. if it still looks good, strip the head and take to a machine shop and cry on there shoulder.
It's very hard to work on your own car, you/I start to imagine all kinds of problems. it's best to keep testing. When realize I've hire a Ouija board mechanics i fire them ....jim
 
Just got car back from shop, head had some minor rough spots and was corrected at machine shop, new head gasket was installed, block was checked and is within spec. Engine temp was correct on drive home and coolant loss was small and typical of amount spit out before big problem appeared. I'll take it out for a full run this weekend and if it performs as it did on the way home, I may have the "mystery" solved.

Thanks for all the ideas, most of which I would up trying (wish the cheaper versions would have fixed the problem).

Art
 
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