26 replies to this topic

[Rallye67]

hi got a 1998 cooper , fan is a bit noisy  stripped heater out & noticed resistor is broken .... it is a resistor isnt it?

struggling to find one  , any  help much appreciated 

Attached Files

•  IMG_6909.jpg   28.41K   22 downloads
•  IMG_6910.jpg   27.98K   17 downloads

[Rallye67]

or if anyone knows the value  could i put a resistor in ?

[jaysmini1983]

google is your friend.

 

http://www.minispare...ck to catalogue

[Rallye67]

google is your friend.

 

http://www.minispare...ck to catalogue

I rang them & they said they didnt do it !!!! 

[Rallye67]

can't  believe this is £42  .... its a bit of coiled fuse wire !!!!

[Stevie W]

Just checked Minispares website and they have it in stock, although I agree £42 seems a bit steep!

Cheers, Steve.

[ClassicBRG]

Is there no alternative, for example by soldering a resistor in between?

[alex-95]

I've fitted a resistor from a rover 200/400/600/25/45 MG zr/zs to a SPI heater, would be pretty much the same do on an MPI. 

https://www.ebay.co....872.m2749.l2649

 

 

 

So one of the winter improvements was the heater, I modified it so that it would fit flush with no dash rail padding fitted (pics of it a few pages back) but when the fan was switched on it would push the mechanism down to the car position  . So with a bit more thinking, the mechanism was improved so now it stays in the position it should. Another thing with the single speed SPI heater it's fast and noisy so I wanted to change it to a 2 speed heater like the MPI (1 of only 3 good things about them, The others being the seats and the intermittent wiper switch ) So I had a look at how the MPI heaters were slowed which is just a resistor fitted into the heater so the fan cools the resistor when it's on. I had a look on ebay and found a rover one clicky  which when it turned up, was a bit big.

 

 

 

Not a problem though...

 

Just needs to be cut to these sizes, I cut a template from card then placed it on the heater where it needed to be and traced and cut a hole for the resistors to go through. notice the corner cut off for the clips to attach still. We found it had to be cut to one side as the resistors were close to the heater body.

 

 

 

Once the holes cut I drilled the mounting holes. ignore the black screw, bit of trial and error...  I powerfiled a curve on the side to curve with the heater body and cut a rubber seal out of a bicycle inner tube.

 

 

clearance to the fan.

 

 

 

 

 

We temporarily wired it up the H and L terminals which with full power gives the 12v and on the other speed is 8v which I think is roughly what the MPI speed is. Now I just need to wire it fully into the car.

[Rallye67]

Is there no alternative, for example by soldering a resistor in between?

 

Is there no alternative, for example by soldering a resistor in between?

well you'd think so  , just trying to find the wattage of the motor 

[Rallye67]

Steve 220  posted this back in 2017  , 

I've got another twin speed heater unit here but the resistor has snapped. I've also got the original from the car and my plan is to replace the dated curly wire resistor with either a wirewound or metal film one.

 

My days or electronics and maths are behind me so thought i'd ask here. A few facts to lay down first.

 

Motor - 12v 1amp (as per wiring diagrams and research)

Resistor on working unit - fluctuates between 3.6-4 when set to 200 on multimeter.

 

Don't know what wattage resistor i will need - or in fact what resistor i will need.

[phillrulz]

Steve 220  posted this back in 2017  , 

I've got another twin speed heater unit here but the resistor has snapped. I've also got the original from the car and my plan is to replace the dated curly wire resistor with either a wirewound or metal film one.

 

My days or electronics and maths are behind me so thought i'd ask here. A few facts to lay down first.

 

Motor - 12v 1amp (as per wiring diagrams and research)

Resistor on working unit - fluctuates between 3.6-4 when set to 200 on multimeter.

 

Don't know what wattage resistor i will need - or in fact what resistor i will need.

 

 

Could just measure diamter of wire, count number of turns on the new one buy some nichrome wire to same spec and solder it on easy. 

[MikeRotherham]

 

I've fitted a resistor from a rover 200/400/600/25/45 MG zr/zs to a SPI heater, would be pretty much the same do on an MPI. 

https://www.ebay.co....872.m2749.l2649

 

 

 

So one of the winter improvements was the heater, I modified it so that it would fit flush with no dash rail padding fitted (pics of it a few pages back) but when the fan was switched on it would push the mechanism down to the car position  . So with a bit more thinking, the mechanism was improved so now it stays in the position it should. Another thing with the single speed SPI heater it's fast and noisy so I wanted to change it to a 2 speed heater like the MPI (1 of only 3 good things about them, The others being the seats and the intermittent wiper switch ) So I had a look at how the MPI heaters were slowed which is just a resistor fitted into the heater so the fan cools the resistor when it's on. I had a look on ebay and found a rover one clicky  which when it turned up, was a bit big.

 

 

 

Not a problem though...

 

Just needs to be cut to these sizes, I cut a template from card then placed it on the heater where it needed to be and traced and cut a hole for the resistors to go through. notice the corner cut off for the clips to attach still. We found it had to be cut to one side as the resistors were close to the heater body.

 

 

 

Once the holes cut I drilled the mounting holes. ignore the black screw, bit of trial and error...  I powerfiled a curve on the side to curve with the heater body and cut a rubber seal out of a bicycle inner tube.

 

 

clearance to the fan.

 

 

 

 

 

We temporarily wired it up the H and L terminals which with full power gives the 12v and on the other speed is 8v which I think is roughly what the MPI speed is. Now I just need to wire it fully into the car.

 

Have you got a rough wiring diagram of the completed heater connected up?

 

Why did you pick that spot to site the resistor as opposed to where the factory one is fitted. Was it the size of the resistor that dictated that?

Edited by MikeRotherham, 05 February 2020 - 12:50 PM.

[alex-95]

 

 

I've fitted a resistor from a rover 200/400/600/25/45 MG zr/zs to a SPI heater, would be pretty much the same do on an MPI. 

https://www.ebay.co....872.m2749.l2649

 

 

 

So one of the winter improvements was the heater, I modified it so that it would fit flush with no dash rail padding fitted (pics of it a few pages back) but when the fan was switched on it would push the mechanism down to the car position  . So with a bit more thinking, the mechanism was improved so now it stays in the position it should. Another thing with the single speed SPI heater it's fast and noisy so I wanted to change it to a 2 speed heater like the MPI (1 of only 3 good things about them, The others being the seats and the intermittent wiper switch ) So I had a look at how the MPI heaters were slowed which is just a resistor fitted into the heater so the fan cools the resistor when it's on. I had a look on ebay and found a rover one clicky  which when it turned up, was a bit big.

 

 

 

 

 

Not a problem though...

 

Just needs to be cut to these sizes, I cut a template from card then placed it on the heater where it needed to be and traced and cut a hole for the resistors to go through. notice the corner cut off for the clips to attach still. We found it had to be cut to one side as the resistors were close to the heater body.

 

 

 

 

 

 

Once the holes cut I drilled the mounting holes. ignore the black screw, bit of trial and error...  I powerfiled a curve on the side to curve with the heater body and cut a rubber seal out of a bicycle inner tube.

 

 

 

clearance to the fan.

 

 

 

 

 

 

 

We temporarily wired it up the H and L terminals which with full power gives the 12v and on the other speed is 8v which I think is roughly what the MPI speed is. Now I just need to wire it fully into the car.

 

Have you got a rough wiring diagram of the completed heater connected up?

 

Why did you pick that spot to site the resistor as opposed to where the factory one is fitted. Was it the size of the resistor that dictated that?

 

 

I don't think I do but can get one sorted in the next couple of days, I've got 2 switches though, one for on and off , one for low and high speed. Shouldn't be that much different.

 

I can't remember why, I think it was to give better air flow over the resistor to cool it down. 

[MikeRotherham]

Thanks for the responses.

 

I think the job is great and one that I've been thinking about doing for a while.

[alex-95]

Thanks for the responses.

 

I think the job is great and one that I've been thinking about doing for a while.

Heres a quick wiring diagram dad drew. On the top diagram, the light green/orange may be light green/yellow as well. If you get one of these switches (or similar) http://www.minispare...ct/Classic/Elec then The 2 speed MPI diagram can be used. If you get an on/off and a on/on switch then use the "2 switch's" diagram. I hope they make sense, give us a shout if not.

Attached Files

•  IMG_7099.jpeg   23.7K   35 downloads