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jlkirsten

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I'm fighting an overheat problem in my BJ8. I've had the radiator cleaned, replaced the hoses and thermostat (180°F), checked the timing. The car still runs between 190°-212°F. I'm prepared to spring for a new radiator, but want to hear some ideas as to whether the stock replacement will do the job or whether I need to go for a higher efficiency re-core and or install an oil cooler.

Thanks in advance.
 
Hi JL,
Welcome to the forum.
I would first check the temp gage. Put a thermometer in the radiator filler neck & check it against the gage.

A 180 thermostat may not be fully open until it reaches 190 plus. 200 to 212 is not really that hot. The actual boiling point is likely 235 plus. 200 plus is not an unusual temp for the car. Has it ever actually boiled?

If it really bothers you or if the temp actually goes higher than this, there are some very good, more modern radiator core designs that most good radiator shops can install in your tanks & mounts. An oil cooler would only do about 10 percent of what a more efficient radiator core would do. A better core would certainly give peace of mind on the issue. I know it is sometimes hard to tolerate a gage reading 200 when you feel that it should be 180 or less.
D
 
You better hope the problem is simple and not the radiator! Before I would buy a new radiator, I would have it flushed and cleaned at a radiator shop. Much cheaper than $800 for a new one. I discovered yesterday when removing my radiator that do to the exposure to salt years ago, the fins are blowing away. Hopefully I can have it re-cored or find a good used one.
 
HI Sarge, Have the radiator recored with a Four core serpintine core should run Less than $300.00.---Fwiw---Keoke
 
JLkirsten, The 180 Degree thermostat is not compatible with CA weather Change it to a 160 Degree unit and that may help. Changing the fan to a Texas Cooler will also help bring the temperature down.---Fwiw---Keoke
 
Hi Keoke,
Prices must run higher in my part of the country. Of course, my experience was with a Healey Hundred which has a different radiator. I agree with your advice.

The original radiator had 5 rows of 1/2" tubes, 150 tubes total, with plate type fins spaced at 10 per inch.

The new core was a "Transpro", 4 rows of 5/8" tubes more closely spaced, 192 tubes total, with serpentine fins spaced at 14 per inch.

28% more tubes, 25% wider tubes, 40% more fins. Cost of new core on my tanks was $500. The shops could get a custom size & spec core from Transpro in about two days. Still worth the cost since I quite often drive in 100 degree plus weather. The more dense core did require a "better" fan to move the air through at low speeds.

On hot days, my 160 thermostat runs at 180, the 180 thermostat runs at 190. Since the winter temps here seldom get below 20 degrees, I just leave the 160 in year around.

JL,
Make sure that you have the correct -not cheap- thermostat installed. The correct one has a sleeve on it that blocks the bypass flow channel when the thermostat is open. Without the sleeve, part of the coolant never goes through the radiator when the thermostat is open. As I said earlier, the peace of mind that goes with a "good" more modern radiator core can be worth a lot even if it is technically not needed.
D
 
[ QUOTE ]
Hi Keoke,

The new core was a "Transpro", 4 rows of 5/8" tubes more closely spaced, 192 tubes total, with serpentine fins spaced at 14 per inch.

28% more tubes, 25% wider tubes, 40% more fins. Cost of new core on my tanks was $500. The shops could get a custom size & spec core from Transpro in about two days. Still worth the cost since I quite often drive in 100 degree plus weather. The more dense core did require a "better" fan to move the air through at low speeds.
-----------------
Interesting--

That the same spec's (not sure of the source) for the upgraded core that I had installed about three years ago. As I remember it cost about $350-400 including labor on my tanks but I believe it was shipped from someplace in the Southern states.

Prior to the upgrade my car overheated both in traffic and at sustained high speeds over 80 mph. The larger tank took care of the high end problems but nothing has helped with traffic so much as the Nock 5-blade flex fan which I recently installed at Dave's suggestion. It reduces temperatures about 10 degrees all across the line and pushes much more air past the radiator (and apparently the carb bowls) as I have not had any problems with high temps or serious vapor locking since its installation.
 
[ QUOTE ]
but nothing has helped with traffic so much as the Nock 5-blade flex fan which I recently installed at Dave's suggestion. ------- and at sustained high speeds over 80 mph.

[/ QUOTE ]
Nock 6-blade flex fan. They DO cruise nicely at 80 plus when everything is right.
D /ubbthreads/images/graemlins/smile.gif
 
Them fellas must be talking about 80 Degrees. I don't even need a fan to do that...Keoke /ubbthreads/images/graemlins/laugh.gif But just for the record,just how many blades does that Nock fan have??? /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/grin.gif
 
you mean to say some of you guys ever at any time any were drive slower then 80m.p.h ???????/they do that on the small narrow side streets here in sunny connecticut.check the attachment to see what happened to my car. /ubbthreads/images/graemlins/crazyeyes.gif
 

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[ QUOTE ]
But just for the record,just how many blades does that Nock fan have???

[/ QUOTE ]

Keoke--

My earlier post was wrong--It has six.
 
Hi Keoke,

The re-coring with a four core surpentine is good advice. Was the origonal factory radiators four core surpentine? A good radiator will help alot during a slow moving parade on a lot day!

Sarge
 
No Sarge, the original radiators were not four core or serpentine finned.,but you also need a fan that will pull more air than the original to complement the upgraded radiator.As a matter of fact a good fan and a clean cooling system will do a lot for the Healey. However, changing these compnents with out the high pressure flushing of the engine block may yield less that the optimum results.---Fwiw---Keoke
 
Well Sarge, thats a shade better than those $800.00 prices I was a hearin good show.---Keoke /ubbthreads/images/graemlins/thumbsup.gif
 
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