one fan fail cause overheating?

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May 5, 2010 | 03:15 PM

martinsw

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From: vista CA

one fan fail cause overheating?

Looking for advice.

My 137,000 mile 98 C5 just overheaded on me yesterday. No problems in the past. The passenger side fan blade came off the motor (left hand nut gone). Radiator looks good, coolant was good.

Do you think that one fan not running at all (at least the blade for it) could cause overheating?

Coolant pump seems ok - no noises when turning. Any good way to test coolant pump on car? Would hate to replace the pump if it is still good.

I WILL put in a lower temp tstat (180 deg) and new upper and lower rad hoses and new coolant. As well as find a new left hand nut to secure the fan blade and locktiting it on (guessing I'll have to get that at the dealer).

Any comments from the all wise tech guru's on CF?

Thanks for any inputs, Steve

May 5, 2010 | 03:25 PM

lucky131969

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From: Dyer, IN

Quote:

Originally Posted by martinsw

How does the temp behave at cruise or at speed? I'm not cooling "guru", but only having one fan running has cut the flow through the radiator (car slow/stationary) in half.....I would not expect a positive outcome. Until the system is restored to working as intended, I don't know how you can go forward with troubleshooting.

May 5, 2010 | 03:33 PM

Eric D

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From: Howell Michigan

St. Jude Donor '09-'10-'11

Quote:

Originally Posted by lucky131969

In fact you can have reverse airflow from the one fan back through the other fan opening at low speeds or idle. This reduces the total air flow through the radiator.

May 6, 2010 | 10:45 PM

fcable

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I have an 02, and I don't know if your 98 is the same. However, on mine, the fans are 2 speed. Low speed comes on at 226 degrees, and high speed at 235. Driving on the highway, you should never get high enough to have the fans come on. When in traffic, or just setting still, I can watch the temperature gauge rise to 225, then it will drop back to 210 or so, and then start rising again, so forth and so on, as the fan cycles on and off.

May 7, 2010 | 12:13 AM

MTPZ06

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From: Honolulu HI

I would say yes...especially if your doing stop and go driving, and if you're running the A/C.

May 7, 2010 | 03:39 AM

RLYSLO

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From: Plano Texas

St. Jude Donor '08

I had one fan go out and yes, it caused an issue when stopped in traffic. At speed of course it wasn't an issue at all. I also had quite a bit of junk clogging up the radiator.

May 7, 2010 | 01:36 PM

martinsw

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From: vista CA

Thanks for the inputs! Much appreciated.

Fans now both working again (locktite on the left hand nuts). Going to replace my balancer 'while I'm there' as it IS wobbling and belt chirping.

Any good way to test a water pump on vehicle, or maybe I should just replace anyway given the high mileage?

May 7, 2010 | 01:41 PM

lucky131969

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From: Dyer, IN

Quote:

Originally Posted by martinsw

I'm not sure how you would evaluate the pump itself, aside from evaluating output pressure and volume. Seems to me, an engine that operates at the correct temps, and maintains said temps, is the best test of the pump. Whether you replace or not is up to you. If you do decide to replace, I would go with a new, as opposed to reman'd.