my friend has been building a mustang for a while now but is having trouble keeping the 351C in his hatchback cool. he has a 4 core aluminium radiator and a stock fan from an SN 95 mustang. the problem is we cant get the fan wired right, or we dont have enough relay to keep us from blowing the 30 amp fuses.

so any suggestions would be great. this fan flows too much air to give up on but when you first switch it on it spikes so power that the fuses go.

another question, are relays rated for continuous pull? would a 75amp relay hold up to 75 amps of continuous pull?

thanks alot guys

 

get a ford relay that was made for that fan and adap to the system. that way you know it has the correct amperage rating. are you sure that you have it wired correctly?

 

yes were sure its wired correctly. got the diagram offline from someone who did the same thing with a less powerful fan. we just didnt want to pay dealership price if it could be avoided but our 40 amp relay wasnt enough. the fan pulls a constant 33 amps but when it first switches on it spikes way higher and that blowing fuses and relays all over the place.


thanks

 

Sounds like you need to find out what kind of the amperage the fan is pulling when it is first turned on. That way you know what size fuses and relay to use.

Have you checked with the fan manufacturer to see what they recommend?

 

There is something wrong if the fan pulls that much current. You more than likely have internal shorted windings. You need to find out the size of the fuse that it was used with in the car it came out of. Also some motors are marked with the current requirements but I'm guessing you already looked there.

If you have a motor that pulls too much current initially, a large capacitor across the input leads can help alleviate the spike problem. But you need another fan.

 

I don't know much about Muskrats but I just checked the wire diagram for a 95 5.0 and see the fuse for the fan is 60A. and uses a relay. I humbly stand corrected. Apparently it does pull over 30A regularly.

Guess you need a bigger relay and a 60A fuse.
BTW, it also used a solid state controller for the relay.

 

thanks slopok, knew it was quite a power drawing beast. thanks for the info.

 

Just like Slopoke said Hook up a capacitor. Even on high power relays, everytime they connect/disconet the power there is a small spark generated in at the Relays contacts and this will eventually eat the contacts. Youd be surprise how much longer a relay last when you ad the Capatitor. Now for low power applications it doesnt really matter but in your case I would recomend it hands down..


Marvin