Jeff20B

iTrader: (13)

ray green, yeah they look kinda cool. Different anyway.

You should compare your regular stock steel one with the chevy type at napa or wherever. If it's close, you could always hog out the mounting holes a little. A couple mm off isn't bad. That's what sealant is for.

If I had to chose, If the waterpump was removed, I'd mount the sender in the housing on the back side (easier to cut threads and clean the shavings if necessary). If it's installed and I had an old style themostat cover, I'd mount the sender in it and just be aware that it's after the thermostat instead of before it.

I wouldn't bother with the drain plug location because it's kind of low and would be too heavily influenced by oil temp (have you seen the base of an intermediate plate?). It;s also kinda small. I haven't tried the front plate location although the nitrided R5 engines had a BSP-threaded sender there. I think it's smaller than the 12A Y castings and their hex plug. I think Mazda plugged it to allow for the beehive oil tube. If I remember right, the R5 temp sender is longish and interfrs with the oil tube. I know this because when I attempted to use a beehive on a nitrided R5 engine (13B), I had to shorten the sender to little more than a brass nub no longer than the hex plug on the 12A plate. It worked.

ray green

iTrader: (14)

Thanks Jeff, being one who wants the best job for the least effort, your super cool (no pun intended) thermostat housing looks like the way to go. I do have some misgivings about putting Chevy parts in my RX-7, it just ain't right. So if anyone on has an actual old school Mazda one for sale, I'm prepared to pay the big bucks.

I had the same concern as you point out about mounting it down low in the drain plug, easy but maybe not real responsive to quick changes in engine temp. I wan't sure why, but as you point out there is good oil cooling down there that might dampen the response.

I don't want to mount it in the front plate location unless there is a very good reason, since the AC unit is still installed, which would require removing that and probably some retooling, as you described for your R5 engine.

And tapping it into the radiator hose is just too cheap and easy.

I'm not too worried about the quirk with the thermostat not opening and causing false readings at the T'stat housing, after all the stock temp guage works fine almost all the time. The only reason I want another one is to get a second opinion when (and if) the stock one shows this weird behavior of drifting up into the hot zone again.

In the mean time I'll hit Autozone to see if they can match one of the spare thermostat housings I have out in the parts shed. Anybody want to trade a old school T'stat housing for an new school one, in excellent condition and freshly painted?

Thanks Jeff and Doc, who first suggested hoofing it up to Autozone.

Ray

Jeff20B

iTrader: (13)

I put a sender in the radiator hose on one of my projects. It works well enough.

ray green

iTrader: (14)

OK Jeff, if it's good enough for you, it's good enough for me. I'll put it in the hose. Underneath, where it doesn't show.

Does Autozone make a cheap verion of that steigger adapter?

legokcen

iTrader: (8)

You can find them on eBay for like 10-15 bucks, with shipping it was $19. That's how I got mine and it works great. ISCracing.net has them for $25.

Here's one:

http://cgi.ebay.com/ebaymotors/water...QQcmdZViewItem

ray green

iTrader: (14)

Thanks Lego, at least they are not made by Chevy. I wouldn't want anything even remotely related to a V8 in my 7. I'll check down at Autozone, if they don't have one I'll go online.

And thanks to Kim who first suggested this cheap-*** solution.

Ray

Kim's FB

Ohh C'mon Ray, there's nothing wrong with cheap and easy (if it works)
Better that expensive and complicated Some of the best modifications out there for our cars are cheap and easy.

If you do go with the hose adapter make sure that you know if your sender needs ground. Most likelly it will, so you will have to run a wire from the adapter to a ground.

Siraniko

iTrader: (13)

Do you want any of these junks?

ray green

iTrader: (14)

I'm liking that one on the right wacky.

I'd love to have a Kim boat with one of those cool aftersensors, but I'm stuck with a 25 year old unmolested virgin GSL (and two others, not a bad life):



I went out and popped the hood with Kim's rad hose idea in mind, took this picture and realized it wouldn't work, I just couldn't do it.

So I'm thinking Matthew's put it in the drain plug method is a pretty good one afterall. Anybody out there been there, done that?

Then wacky says take a look at this, and sure enough I like that one on the right. Put it on my parts polisher:



with a nice brass fitting:



and it just might look pretty good.

How much?

Thanks
Ray

PS Oh yeh forgot to mention the guage is one of those el cheepo sunpro mechanical ones, just like the one in Jeff's picture. Should work perfectly.

Siraniko

iTrader: (13)

nope. You wont get an accurate reading from that Sunpro gauge. Look at the probe. Its not 100% sealed, instead, it is secured by that loom. On a stop and go traffic, it will pick up additional heat from the engine bay.

ray green

iTrader: (14)

OK, given my ongoing issues with a wandering temperature gauge, I need to install my mechanical sunpro gauge ($14.99, with tax; autozone):



So, until I save up enough money to get one of those sweet old school ones like Wacky's got (on the right):



I'm thinking Kim had the right idea after all, thanks Kim:



I'll sacrifice one of my old spare upper radiator hoses for the job instead of using my good one:



But why are these simple little water adapters so hard to find? Autozone and Carquest, our local parts stores don't have them. I wanted to do it today but it looks like it's going to have to be a mail order.

Also Wacky, I agree the ACCURACY of a sunpro gauge won't be the best, but the actual temp really doesn't matter unless you are in a testing facility or lab. What you want in a temp gauge is a reliable measure of CHANGES in coolant temp that would indicate a problem. My el cheepo mechanical sunpro gauge should work just fine for this and I won't have to add a ground wire to the rad hose.

So if anyone has one of those in line units or better yet an old school thermostat housing like Wacky's got, I'd sure be interested - tomorrow I put in the $25 mail order.

Ray

Siraniko

iTrader: (13)

True but you want something much more reliable than a sunpro or a autogage; I have used them before and will never go back again. With the SOCAL traffic (lots of stop and go), you want something better. What ground wire are you referring too? mechanical gauges got no ground wire.

For the almost the same price range, check http://www.partsamerica.com/ProductD...goryCode=3342D

ray green

iTrader: (14)

That is a nice looking gauge. I was hoping for a cheap and easy way to install a second gauge but this is turning out to be a major enterprise just figuring out how to do it, so I might as well do it right. And I suppose it's better to be sure you are getting something that will work before you put it in.

I wonder if Advanced Auto has that in stock (yes I'll call when the store opens up). More important, I wonder if they sell either one of those water hose adapters or maybe even a tapped thermostat housing I could use (Autozone and carquest didn't; I'll check around the Adv. Auto website, thanks for the link).

To make matters worse, my neighbor Bobby, who is pretty much a genius about all things mechanical, electrical, heating and cooling, said he thought a sensor mounted after the t'stat would be of little use, since it would be changing all the time when the t'stat opens and closes and never really give an accurate reading of engine temps. According to Bobby, tapping a sensor after the t'stat would probably only be effective for an electrical fan.

Is the t'stat really that out of sync with the engine temp? I thought this would only be a problem in the unlikely event that the t'stat failed (ie the temp difference would never be more than a couple of degrees).

Since the sunpro gauge is a mechanical one, there would be no need to ground it if I put it in the heater hose, unlike with an electrical one, so I wouldn't have to add a ground wire at all. Again I thought this would be cheap and easy, but given the nuisance of everything else adding that ground wire wouldn't be much trouble (you just insert it at the junction of the hose and adapter, then clamp it in).

So maybe I'll try Advanced Auto today.

Am I really the first one on earth that's tried to do this?

Siraniko

iTrader: (13)

Ray,
While looking at my RX-3 with modified 1st gen radiator and 2nd gen (S4) t-stat cover, it clicked on me that I have done prior gauge installation on a S4 t-stat housing. Let me see what I can do since I have an extra one and I have the pipe tap also.

You're not the only one. I have tried almost eveything in the past 20 years (do I need to say more??). Also, autometer gauges arent that accurate either. But the main idea behind installing gauges is to get a "second opinion" particularly on old cars. Years ago, I blew a newly built and installed streetport on my RX-4 due to faulty stock water temp gauge.

ray green

iTrader: (14)

Thanks Wacky, it's reassuring to know it's not an unreasonable idea and that others have done it for the same reason I want to, to get "a second opinion" in case my twenty three year old stock gauge isn't up to the job. In fact if I can ever figure out how to do this I'd like to put one on all my GSLs, since engine temps are so important in rotaries.

And who knows, maybe it will be a good idea for other rotor heads too.

So yeh if you have a housing that would solve my problems I'd be very grateful and could swap money or 84/85 GSL parts, I have a shed full and might have something you could use.

As far as whether putting the probe after the thermostat is an accurate or reliable way to check on engine temps, I'm inclined to just try it and see, if it fluctuates with the t'stat opening and closing at least I'll be getting some information about how the cooling system is operating. And if it doesn't, well everything will be just fine. After all, reasons don't count, only results.

Thanks

Ray

trochoid

iTrader: (6)

Some of the FCs have a thermo neck with a sender. It's usually found on the TIIs with AC and turns on an auxiliary cooling fan mounted in front of the radiator. The S4 necks are cast aluminum, the S5s are plastic. Never checked them for interchange with 12As.

Siraniko

iTrader: (13)

S4 t-stat cover will fit a 12-A/13-B stock water pump housing. you just need to grab the long bolt and if you dont mind having 2 radiator caps.

ray green

iTrader: (14)

OK, I should know this by now, but the best thing is to always go stock. So with the help of good neighbor Bobby we took this t'stat housing and fixed it up some. I'll let you know when I get it in.







Ray

legokcen

iTrader: (8)

I just installed the Sunpro 16mm adapter and it fit perfectly.

Jeff20B

iTrader: (13)

Hey that's pretty nice, Ray. Let us know how well it works.

legokcen, was that adaptor for an electric guage?

legokcen

iTrader: (8)

Yes it was. 16mm to 1/8 NPT for an Autometer Temp gauge.

Jeff20B

iTrader: (13)

I have one of those too. They don't help when you have a mechanical guage though, like Ray.

ray green

iTrader: (14)

Yup I was looking for a mechanical one to check up on the stock electric one. And I got it in:







Use shu glu to seal the slit in the speedometer cable gasket:



Use the two holes for attaching dash parts to screw the gauge in:



Now the good part, I get to see what the mechanical one does when the electric one goes wacky.

Ray

ray green

iTrader: (14)

And here's one more:

trochoid

iTrader: (6)

Ray, I wish most of the other members took the time and care with thier 7's that you do with your's. Top notch, keep up the good work.