Electric fans burning out the fuses - Page 2

spdbrake · #21 (**permalink**) 06-04-2020, 08:24 AM

Quote:

Originally Posted by Gaz64

And we have found start up current as the cause, as it nearly always is with electric motor faults.

I would swap your fans over, to prove the the fault to afan motor or EMF from the alternator. I will say the fan motor.

I don't think you have any other "resistances", otherwise they would be glowing with 100 amp spikes, so your wiring is good.

Gaz is correct, https://www.youtube.com/watch?v=gWJFzAMsIlc
and I'd also add pi$$ poor connections add to the excessive Amperage issue. Those are brush fans and as such are life limited on the service life. To isolate each fan I'd connect them one a time to a battery directly. Use an induction clamp on AMP meter. Taking the car out of the equation.
Reading your 1st post this issue started after the fuse holder replacements, so I'd relook at those connections for a the actual number of copper strands in each connection. (Just a few strands=Hi-AMP under load). Many of the cheaper wire strippers nick the copper strands and leave you with just a few actually intact.

patrickt · #22 (**permalink**) 06-04-2020, 08:39 AM

Quote:

Originally Posted by spdbrake

Reading your 1st post this issue started after the fuse holder replacements, so I'd relook at those connections for a the actual number of copper strands in each connection.

I think that's a tip. Any time a problem has mysteriously appeared right after I did an "improvement" to the car, I know where to look first....

BAsque1 · #23 (**permalink**) 06-04-2020, 03:01 PM

Quote:

Originally Posted by Gaz64

And we have found start up current as the cause, as it nearly always is with electric motor faults.

I would swap your fans over, to prove the the fault toa fan motor or EMF from the alternator. I will say the fan motor.

I don't think you have any other "resistances", otherwise they would be glowing with 100 amp spikes, so your wiring is good.

I am doing a stand alone test with an online ammeter straight to the battery, bypassing the car motor and see what is the kick on amperage and then consider the fan replacement if needed.
This is really annoying now!!

Michael C Henry · #24 (**permalink**) 06-04-2020, 05:33 PM

I've watched the old electric motors with brushes being replaced with brushless motors. The fan in my gas heating stove, then the Dewalt cordless drill drivers. why not electric fan motors on cars? They are more power efficient than the older brushed versions. Why wouldn't the brushless technology eventually be used on electric fans for cars? It may already be available in a better brands, Again I do not know I suppose then there are warehouses' full of the old fan versions, yet to get rid of.

patrickt · #25 (**permalink**) 06-04-2020, 05:45 PM

Quote:

Originally Posted by Michael C Henry

I've watched electric motor being replaced with brushless motors. The fan in my gas heating stove, then the Dewalt cordless drill drivers. why not electric fan motors on cars? They are more power efficient than the older brushed versions. Why wouldn't the brushless technology eventually be used on electric fans for cars? It may already be available in a better brands, Again I do not know I suppose then there are warehouses' full of the old fan versions, yet to get rid of.

My SPAL puller is brushless, as is almost all of their fans (but not all), but my pushers use brushes.

Michael C Henry · #26 (**permalink**) 06-04-2020, 05:55 PM

There you go , I didn't know. Sounds like something I thought would happen. Yet another point to look for if and when shopping for replacement cooling fans next time. I have no problem with my fans at this time but they are at least 35 years old. So this experience may be used in the future.

CHANMADD · #27 (**permalink**) 06-04-2020, 11:06 PM

Those little fuses are not good for a high draw like fans, or fuel pumps.....they get hot and eventually fail....Fans and fuel pump should run relays, and have an inline large fuse for the main relay power wire..

CHANMADD · #28 (**permalink**) 06-04-2020, 11:14 PM

Those little fuses are not good for a high draw like fans, or fuel pumps.....they get hot and eventually fail....Fans and fuel pump should run relays, and have an online large fuse .

BAsque1 · #29 (**permalink**) 06-09-2020, 04:23 AM

UPDATE On fans issue:
Yesterday I tested the fans isolated from everything, placed the ammeter on line and each fan by itself, the initial amperage was 45-50 amps to kick on at 205o. Checked all connections ground etc and all are fine. Relays are working fine, I replaced the mini fuses for 30 amp circuit breakers. I changed the radiator cap for a brand new one 13lbs as required in the event that the old cap was not venting properly and added Water wetter to the coolant. At this point I am watching and see if it happens again.

Ron61 · #30 (**permalink**) 06-09-2020, 04:37 AM

Lou,

I hope that will correct the problem but if it doesn't send me an email and tell me everything that you have done. I had a friend who had a similiar problem and it turned out to be the last thing we suspected and they tested good on every test. It was just pure luck that we found out what it was. Heck, we even ran new temporary wiring to the fans on his car to make sure there was no intermittant short. But I hope this takes care of your problem as things like this can really be annoying.

Ron

BAsque1 · #31 (**permalink**) 06-09-2020, 05:28 AM

Quote:

Originally Posted by Ron61

Lou,

I hope that will correct the problem but if it doesn't send me an email and tell me everything that you have done. I had a friend who had a similiar problem and it turned out to be the last thing we suspected and they tested good on every test. It was just pure luck that we found out what it was. Heck, we even ran new temporary wiring to the fans on his car to make sure there was no intermittant short. But I hope this takes care of your problem as things like this can really be annoying.

Ron

Good morning Ron:
Tks for your quick reply, well I have checked all connections, changed the mini fuses and use mini circuit breakers instead, isolated the fans and checked the amperage with amp meter, the kick on as expected 205o the initial draw was approximately 50 amps and then goes down to 40-45 while running, turn off at 195o all this is normal. the fans are freewheeling do not show binding or hangups. Changed the radiator cap for a new one 13lbs vented, I was unsure of the venting of the previous cap. I did this because i noticed the puke tank side hose collapsing after cooling off but if it was vented this should not happen. So I changed the cap. I added water wetter to the coolant mixture. Check the online fuse of the hose temp sensor for the fans, that is fine. Test run the car (ambient temp 80o) open road remained at 190o, at a light stop went up to 200o all is fine so far. I will stay away from slow city cruising that is murder for these cars. So far this is all I have done.
tks
Lou
PS
Yes it could be very annoying

ng8264723 · #32 (**permalink**) 06-13-2020, 08:33 PM

Does he have high amp relays on these fans? I use a relay that is fed from the alternator. Am I wrong here? I mean does this car have a nice big relay?

ng8264723 · #33 (**permalink**) 06-13-2020, 08:37 PM

That what I figured he needs a relay...……….
Add this
https://www.amazon.com/TE-tyco-Curre.../dp/B00OHRZ782
Use fusible links to power it up. Wire directly from the alternator and do not use your fuse panel to power anything except the relay. Overtime it will get worse

Michael C Henry · #34 (**permalink**) 06-13-2020, 11:24 PM

I'd go with circuit breakers on a lot of electrical control points If you can fix or eliminate what ever tripped the breaker you can reset it and get to some place for help. When I first had the car I went to my nephews house and left late. The head light switch burnt out and I went home with the flashers marking the curbing to get home. You burn a fusible link and your done. But you have to find and fix the problem first or a circuit breaker will just l trip again. and circuit breakers do get tired and used up if used at or near their limit much.

BAsque1 · #35 (**permalink**) 06-14-2020, 06:08 AM

Quote:

Originally Posted by ng8264723

Does he have high amp relays on these fans? I use a relay that is fed from the alternator. Am I wrong here? I mean does this car have a nice big relay?

Yes both fans are connected to a relay (one for each fan)

ng8264723 · #36 (**permalink**) 06-14-2020, 07:04 PM

How big are the relays? The relay should not blow the fuse. What is the fan power source for the relay?

ng8264723 · #37 (**permalink**) 06-14-2020, 07:43 PM

Check this out. There is load on that wire. It does not make sense it should just be turning on a relay.

Dwight · #38 (**permalink**) 06-14-2020, 07:58 PM

Quote:

Yes both fans are connected to a relay (one for each fan)

If you have two fans and a relay for each then you should have two fuses, one for each relay. Correct?

ng8264723 · #39 (**permalink**) 06-14-2020, 08:15 PM

Well it depends what they pull amp wise. But two is better. I like the one relay set up with the volvo system above. I have used a single 75 amp Bosch relay to power a Mark VIII fan. They work well. I have hooked them up to a mech. switch or a temp switch. Both work well.

BAsque1 · #40 (**permalink**) 06-16-2020, 04:56 AM

UPDATE ON THE CAUSE
After much digging it all came down to the hose that holds the thermostatic switch for the fans( top hose) it was a contraption ready to literally blow with two hose components totally collapsed due to the weight of the design of this contraption. a brand new hose is being professionally made and hopefully this situation is corrected.