QuestionQUESTION: 50k on the motor, new hoses, new fan clutch, new water pump, new belts, new temp gauge sending unit, and removed thermostat, but it still overheats in summer stop and go city traffic with a/c running; no problems at highway speeds. Finally rewired a/c fan so it runs all the time to better cool the radiator, plus put in some "Wetter Water" additive. The a/c fan modification helped a teeny bit. The aftermarket radiator is 3 years old, been flushed, doesn't leak and has good pressure. Also, there's no extra room up front to install a larger radiator. I finally sent a letter to Suzuki Corporation in Japan. Their reply was that there has been no recall of that engine for overheating problems. Been to numerous mechanics and there's nothing left to test... I still have a sneaking suspicion that the water channels in the block aren't big enough to cool the engine with the a/c running in very hot weather, but Suzuki won't admit it...
ANSWER: Something to consider regarding A/C usage and consequently elevated engine temperatures in the summer -
It requires a given temperature differential between the coolant in the radiator and the air flowing through the radiator to exchange sufficient heat to match the amount the engine is producing - as the ambient air temperature rises, so must the coolant temperature assuming the rate of air flow is unchanged.
I'm certain you've noticed that at higher vehicle speeds, which means more air flowing through the radiator, engine temperatures drop somewhat, unless one drastically increases engine load.
The A/C condensor, placed in front of the engine radiator, is significantly raising the temperature of the air flowing through the radiator, in effect adding insult to injury, especially in stop and go and slow moving traffic.
The question is - is it actually overheating - "running in the red", and boiling over, or is it running significantly higher, but not "in the red" or boiling over?
Running near the top of the gauge, but not "in the red", or boiling over is not necessarily unexpected, or out of the ordinary.
A higher capacity condensor fan is sometimes the easiest and usually the most common solution to your problem.
I have similar issues with my 87 Samurai running significantly hotter crawling up steep grades with gearing more than three times lower than stock, and had to install an annoyingly noisy fan in front of the radiator to boost air flow rates.
Truthfully, I suspect that A/C usage in some of the hotter portions of the world was not planned for in the initial design of the radiator's capacity to exchange heat, and that a compromise between capacity and cost of manufacture occurred here, as in thousands of other places in the design of any consumer product.
If you check with aftermarket radiator manufacturers, and off-road specialty shops (izook.com) you will find that radiators with extra rows of cooling tubes can be purchased, and specialized radiators are available.
I believe it's a problem with the radiator's ability to exchange enough heat fast enough under unfavorable conditions.
In many cases, removing the thermostat will result in coolant flowing through the radiator too fast resulting in only partial exchange of heat to the air, and may actually make the problem worse.
If the increased coolant temperature is not causing boiling over, consider the possibility that a major portion of the problem may be less serious than it may be perceived to be.
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QUESTION: Like you, my main mechanic is honest, has over 30 years experience, and even had overheating problems with a 2 door Amigo driven by his wife. He solved her car problems using the solutions he applied to my XLS.. But the Amigo is smaller and I think has a different engine than mine. Even with the original engine my vehicle always ran in the red, and often bubbled over. I replaced the radiator and that helped -- for a while. As you know, running the engine at those heat levels can crack the head....which finally happened to mine This is why I don't want to run this engine hot. And because I have so much money invested building engine #2 versus buying a new car, it almost feels like a slap in the face to turn off the a/c during Las Vegas summer stop and go traffic. I'm going to put the thermostat back in and see if that helps. My mechanic told me a bigger radiator might help if he could find one that fit. He went on to advise me that If he had to make the space larger for another radiator it would run into too much money.
I want to replace the black driver's side door panel but can't find any clean ones from online junk yards. I tried once but the arm rest on the panel they sent me was also cracked. I also need a window motor for the same door, plus that piece of black plastic trim that fits between the driver's side front and back door. The original was broken off during a break in attempt; they still failed to open the doors... My guy has had little luck, but if you can get me a deal on those parts I'll be happy to pay you a finder's fee. I want to keep the vehicle because it's in good condition, good on gas, and this engine looks like new with only 50K miles.
Thanks again for your initial reply.
AnswerThe downturn in the economy has adversely affected the supply of aftermarket parts, and more than half of the businesses that used to be there are gone.
Friends who do desert stuff (mine is almost exclusively high mountain) have placed a twice as high capacity electric cooling fan in front of the condensor (including fabricating some ductwork), and have removed the fan clutch, and installed a metal blade flex fan in place of the stock stuff, which also involved modifications to the original fan shroud.
Vegas is a somewhat temp extreme region, and some non-stock stuff may be necessary.
Is your radiator a single or two row core?
I found that even in the high mountains above 10k feet, it was necessary to replace the stock one row with a more expensive two row radiator.
I looked at autoparts warehouse, and partsbin, and found two row radiators that are supposed to be exact fit.
It's possible that using fan mods to increase airflow will be sufficient.
