Heater motor in engine compartment
 

Does the heater motor in the engine compartment have any other function other than to blow hot air in the the cabin? I just tested my motor and unfortunately its toast!!!!! :crying: :surr:

I was just going to connect it back and just leave it for now. Is this ok? Any suggestions appreciated!!! :thumbup: :thumbup:

If you do a search here, you will find a recent post from me on this very issue. I followed the steps outlined in a series of posts found on Pelican to replace the factory blower motor with a unit from Grainger. It is a fairly easy swap, but for some reason the footwell blowers do not function as before. They are intermittent and infrequent. I have not takent he time to investigate.
The grainger motor was less than $30, whereas the factory motor is more like $300.
Good luck.
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It is nothing more than a heater blower. If it doesn't work, there's no point in putting it back in the car.

You don't say the year of your car - if it's early (pre - 1978 'ish??) and you go for a new Porsche unit you may have to replace the plastic fitting that attaches the motor to the flexi because Porsche changed the design slightly and the motors they new sell don't fit the original fitting.

PJC

Found a place out in AZ http://www.20thstreetauto.com/ that specializes in Porsche parts. Found a heater motor for 100.00 bucks. I guess they are a lot cheaper out there since its hot and there is no need for them. They even inlcued a 4month 4000 mile warranty

The blower crapped out in my '89 so I just unplugged it. This also disabled the footwell blowers. I found that there is still plenty of warm air being pushed into the cabin by the engine cooling fan when I pull up on the red levers.

One other option is don't bother fixing or replacing. Look on the Pelican board regarding "backdating heat." You replace a few ducting pieces at the fan and do away entirely with the blower motor. It frees up the engine bay which not only makes it easier to work on, but also much "cleaner" looking. From everyone who has done it, they say there is lots of heat available w/o the motor ...I can attest that I hardly ever turn on the fan; I just lift the heat lever and get tons of engine-fan forced heat. I haven't done the "backdate" yet, but will whenever my motor craps out. Just food for thought.

Edward

there have been lots of informative threads on pelican regarding this topic. First off you haven't told us what year car. The carrera's rear blower also controls the footwell blowers..in the sense that if it doesn't function it won't allow the footwell blowers to operate. The rear blower on those cars also has an additional task. If the car is stuck in traffic the blower will come on and circulate air thru the heat exchangers to help cool it. Buying a used blower..seems silly to me. They all die back there because of the heat. If you buy a used one..its on its way out. The grainger motor mod is a cheap way out but the current draw on that motor appears to be less then the factory motor. Normally, this would be a good thing but becasue the Engine compartment control relies on that current draw to turn on the footwell blowers, they sometimes don't work. I found a simple mod to the engine compartment controller that will get you around that problem. All that info is posted here:
http://forums.pelicanparts.com/showt...hreadid=258473

Now, If the car is an SC or earlier then you just have the rear blower..which sucks [blows] even when it is working. I backdated the exhaust/heat exchangers on my SC to SSI's. I removed the non-functioning rear blower and re plumbed the heat to 74 style. I added footwell blowers and the difference is dramatic. One of the nicest upgrades I've done to the car.

That thread is very extensive. I had supposed previously that the resistance of the Grainger motor was significantly lower thatn the original unit. Now I see why this difference causes the footwell blowers to function intermittently.
My thanks to all who helped solve this dilemma! I'll be doing the reed switch jumper this weekend, but I'll probably be using a switch mounted to the side of the relay for the ability to engage/disengage the FW blowers.
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Dan

Let us know how it works.

Ian

Well, the mod is completed, and it works like a champ. I went the 'extra mile' on mine and actually used a switch instead of just a jumper.
This gives me the ability to control the FW blowers function if needed/desired.
I mounted the switch directly below the relay and rant he wiring behind/under the aluminum bracket.
I drilled a small hole in the outer cover of the relay and passed the wires through with both heat shrink and an abrasion sleeve on the wires. I would have also used a rubber grommet, but I couldn't find one that fit the hole diameter.
I'll post a pic of the finished product ASAP. The switch looks as if it is a factory item, except for the notch I had to make in the plastic cover for clearance.
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Great news Dan..please post a picture so I can add it to my collection regarding the controller mod. Unfortunately, that thread got shut down because of some bickering among pelicans. It left an unanswered question that maybe other Carrera owners can answer. Does your engine blower come on when the car is turned off and the engine is hot? Someone mentioned this and we have been unable to confirm it.

I have not had the opportunity to determine if this scenario is true or fiction either, as my engine temps generally do not exceed "normal" operating temperatures.
Certainly not for extended periods of time anyway.
I'll get a pick ASAP.
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Glad it worked, Dan. That's on my ever-growing list . . .

Ian

Here are a few pics of the completed FW fan switch mod on my 84. They work as needed with the switch in the up position, and they are 'turned off' (because of the low current draw on the Grainger motor) in the down position.
I'm not sure I would ever want it to be in the down position, but at least I have the choice.
The wiring enters/exits the relay box on the edge next to the mounting bracket. It cannot be seen unless you remove the relay from the bracket.
I had to make a small cutout in the plastic cover to clear the switch, but I wasn't bothered by doing so.
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