Cooling fan relay blowing

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kitchman
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Posts: 132
Joined: Mon Jun 20, 2011 12:24 pm
My tercel:: 1983 2wd tercel hatch back ,1986 SR5

Cooling fan relay blowing

Post by kitchman » Thu Oct 05, 2017 9:02 pm

At first it was thought that the radiator cooling fan was inoperative due to a electrical problem. Unfortunately after spend a good deal of time trouble shooting and replacing the fan relay, which had blown twice, it was discovered that the fan its self was the culprit. The fan blade was very rough to turn. The fan motor was removed and opened, which revealed that the magnets had dislodged from the motors' case. The motor was cleaned up, magnets re-glued, motor reassembled and reinstalled in car. A new relay was purchased pretested and installed. Engine was started and fan engaged when temperature reached target. Unfortunately after a short while (a few minutes), the fan stopped working and did not engage again. The new relay was now blown. The FSM test for the motors' amperage draw did not work. When direct voltage is applied to the fan it appears to operate properly, but it may be drawing more amps than the relay can handle? Any thoughts?

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xirdneh
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My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: Cooling fan relay blowing

Post by xirdneh » Thu Oct 05, 2017 11:53 pm

I got no thoughts 'cause lectricity and i do not get along but i do have some spare blower assys for cost of shipping
Love those Tercell 4x4 wagons but they sure suffer from road noise.

kitchman
Top Notch Member
Posts: 132
Joined: Mon Jun 20, 2011 12:24 pm
My tercel:: 1983 2wd tercel hatch back ,1986 SR5

Re: Cooling fan relay blowing

Post by kitchman » Fri Oct 06, 2017 9:46 am

Thanks for the reply and offer! What do yo mean by blower assy?
Anyway by using a different voltmeter and different wire connections it was determined that the cooling fan is drawing 4.5-4.8 amps. which seams to be normal and should not be causing the relay to blow out. I am wondering if it is because the relay from Rock was there cheapest called Ultra power RY137.

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xirdneh
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Posts: 1677
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: Cooling fan relay blowing

Post by xirdneh » Fri Oct 06, 2017 2:50 pm

its the whole radiator fan unit, i suppose i could remove the motor
Love those Tercell 4x4 wagons but they sure suffer from road noise.

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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: Cooling fan relay blowing

Post by Petros » Fri Oct 06, 2017 8:04 pm

a lot of commy parts (made in communist factories in the orient) are junk out of the box. I have owned a number of very high mileage toyotas, never had a fan relay go out. so a used factory relay may be a better bet than a cheap one from China.

You might also double check all the contacts, if the fan was dragging it would tend to draw more power and possibly cause the wire bundle to overheat, either causing a short (because of melted insulation), or bad charred contacts.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)

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