I've removed the entire water pump housing to install the new switch (yes I know, I didn't need to)

the part I received from PR doesn't fit. It only threads in about a turn and a half before it wont go farther. The OD of the threads is larger than the OEM FD switch. The FD switch screws in far further, so the sensor itself is further into the housing.


Am I losing my mind? I'll post photos in the morning but in short it's too wide and the portion that's threaded is actually tapered so it gets wider the further you go, which explains why I can start threading it and then it completely stops.

And yes, I have the correct hole.

 

They may have changed suppliers so it's an NPT fitting or something. If so that sucks!

May be worth a call to Pettit. If you have to drill/tap to install I'd be inclined to return it.

Dale

 

I prefer the oem switch which comes out of a fc. 41-18-840 is the part number and it is a direct replacement for the fd switch.

 

That certainly seems to be the case.

Thanks - I have to get a bunch of gaskets anyway so I might as well hit up Mazda. Where can I find part numbers? I need the bracket mounted to the power steering pump




OD of valleys between threads (meant to take OD of threads)

OD of threads at top

OD of threads

 

Google for RX-7 parts diagram, there are PDF copies around of the parts microfiche. Some parts (common parts) are easy to find on Atkins Rotary's website - easy way to get the part number.

Or call up Ray Crowe, just tell him what you need and he'll get the right parts for you, no muss no fuss. Best prices too.

Dale

 

The new Pettit Thermo Switch gets installed in a different location (pictured). I have the old one, which goes in the stock location. When we tried to install my friends we had to call Pettit cause we were going crazy.

 

Well the Pettit sensor would be easier to install and access if that was ever needed. But not sure about having it sticking out there from the housing. Just another ugly sensor and wire in the way. And I’m thinking the wire would need an extension to reach...so you have some soldering etc. instead of a p n p.
IMO the S5 FC switch is still the better choice.

 

I feel the same way, I like it better it the stock location. I was just stating what Pettit told me how to install. It’s been a while but I think they send it with an extension.

 

Interesting. To their credit, that does make the install a lot simpler. Big downside is that's on the radiator side of the thermostat - if you have a stuck thermostat, the fan switch will never register, and that's exactly when you want your fans to be kicking on!

I like Pettit, they are good folks, but I would NOT install this switch. Get the OEM FC fan thermoswitch if you are going to do this.

Dale

 

Having seen the FC switch, the part which pettit sells is certainly not the part I assumed it would be

 

That's the plan. I just have to arrange a return with Pettit for this part. It wouldn't make any sense to be out the money twice.

 

The Pettit switch turns the fans on at 185F, might be too cold for the oem 180F thermostat that starts to open at 180F, wide open at ~ 200F. Cooling before radiator is very hot.

 

The parts manager at the local Mazda Dealership says that part number does no exist.

 

i hope he looked up the part the normal way and didnt just leave it at that. even with an incorrect part number, you can still find the CORRECT part number the normal way of looking up parts. you know what the part is and what car it came out of. with 2 pieces of the equation, you can find the 3rd piece.

 

Or call Ray Crowe.

 

Part number should be

PN41-18-840

First part got dropped up there.

Dale

 

whoops don't know how i even did that. Sorry. PN41-18-840 is correct.

 

I tried Mazda online parts sites by Jim Ellis and Montgomery Mazda, and they don't list the thermo-switch anymore, just a thermosensor. Rockauto also does not list it. I suspect it's out of stock, and no longer available. That call to Ray Crowe should find the answer. One dealer contact has already implied it's not available anymore.

 

Call Ray, he can get it (I seem to remember he was stocking them) and if for some reason they are NLA he will know for sure.

Dale

 

Thanks guys

I've been trying to get ahold of Pettit Racing for a week now to return this sensor and I'm getting nothing but crickets.


Admittedly I've only tried facebook messenger and email so far as I don't particularly want to make a long distance phone call.

On their website it says to email them, you click the link and it takes you to the Contact Us page (as expected) when you click on 'Email Us' it simply reloads the contact us page.

 

Okay - problem solved (except getting a hold of Pettit Racing, but that's another problem for another day).

I told the Donkeys at Mazda the full part number, the parts manager insisted that the PN wasn't a prefix but an acronym and therefore not part of the part number. One of his lackey's found the part on the FC diagram. I asked (for posterity's sake) what part number he was getting..

yep
PN41-18-840

SMRT

They're readily available (at least up here) and mine will be in by Wednesday.

Thanks for your help folks.