disabling coolant level sensor
 

I have an after market radiator, and the thread pitch on the sensor I couldn't figure out (wasn't metric, wasn't NPT). I'd like to either replace the stock sensor with an aftermarket sensor with an NPT thread pitch, or at the very least by-passing the sensor so I do not hear the buzz (though I would prefer the former over the latter). What do I need to look for in a sensor to make sure it's compatible in voltages?

I've heard of multiple ways to remove the sensor altogether - but none of them worked. Grounding this wire, powering that wire..........mine would still go off from time to time. Had to rip out the buzzer itself.

As for replacing the sensor, You'd have to check it out. Being one wire I'd imagine its likely a type of switch to ground.....but I ahve no idea, if I ahd one in front of me i'd bust out the DMM and tell you.

But if you decide to delete it altogether - be prepared to pull the gauge cluster and snap (one of the many) the little buzzer off the back of it.

the coolant level sensor is only a piece of conductive metal. when it is grounded, the buzzer turns off. It gets grounded through the coolant to the engine block.

I dunno, I got a KOYO, it's has a factory spot for the sensor, I would try calling them about the thread pitch sizing.

It might be some funky BSPT pitch like the oil pressure threads on the rear iron.

What brand is this? I have never heard of this being a problem.

/\ why do they do that shit? It makes things impossibly difficult sometimes unless you have like a super tap and die set...

Guess I could just make my own sensor... lol. Since my radiator isn't connected to ground i could just take a metallic dowel and have it NPT threaded to screw in. Then solder on a wire. There done, you call me.

Yes, what kind of radiator is it? 1 800 radiator or Performance Radiators are 99% correct except for not being aluminum. Fit well, just aren't as effective as Al unless you get something much bigger. And then there is the cost in that much weight in the front of the car.
Just a point, to make a copper core radiator as effective as an AL you need a lot more core. And they weight a lot more than the Al. I haven't seen that copper cores in the FC or FD in Tucson`work very well.

BTW Thread is 12mm x 1.25

It is a ground switch, water touching it completes the ground circuit.
This is why rubber mounts are not recommended, unless you use a jump wire from one of the rad mount bolts to chassis.

It's an afco radiator and I custom made mounting locations for the temp and level sensor. I also tried a 12mmx1.25 and it didn't work. Oh well, in the mean time I'm just grounding it out and plugging the hole.

I'll tell ya man, a low coolant is the ONLY sensor that I do not have and I kinda wish I did. Of course that would mean that I loose some other warning. I do have an overheat warning, and I'm constantly checking the level so I generally have a warm fuzzy feeling about the whole thing. I would try very hard to keep the sensor if you could.

One possibility would be to tap into the factory waterpump housing and just thread it right in there. I know on the FD housing there is a 12x1.5 fitting that my Motec coolant sensor is threaded right into.

Why not plug that one up and tap it for 12x1.25 an inch over or so? Have someone weld and extra piece of aluminum there if it's not thick enough.

I prefer the NPT pitch and it's already tapped for that. When comparing prices I could make a sensor without issue for about 10 cents when compared to mazdatrix selling them for over $30 a pop. It's not that hard to take a piece of aluminum wrap it or dunk it in thermo plastic/teflon/non-conductive material (though for my application it is pretty asinine since the radiator isn't grounding out against the body--and I used metal and only metal connections, it's a pretty slick way for me to do it, lol shhhhH) and just solder or tin on an electrical connection. It wouldn't be that hard to do at all. In the meantime however I'm not going to waste precious time fabbing sensor when I can do that when time isn't at a premium.

Also, TTT if your stock harness is still intact (though I doubt it is since it's all going through cannon plugs) you can just make your own and use the stock warning light/buzzer without sacrificing an input/warning.

My harness was built from scratch brandy new. I have a few more inputs that I can use, though not on the engine harness. I would have to use the aux harness which would mean I would be better off putting it on the AST if I were to do it at all. Which in all honesty makes the most sense anyway seeing as how that is the highest point on the cooling system anyway. We'll see, I have bigger things to worry about right now although it is on the ultimate shit list to be addressed at some point

I thought that the reason for insulating the radiator from the chassis with rubber mounts was to prevent electrolysis in the coolant system?


As far as the threads not working: Perhaps its what's called "interference" thread? I used a tap and die set from Snap on, and when I tried to "die" a stripped stud on a coilover, it did not want to work with me, however I knew for a fact that it was the right thread size....

Sometimes threads are just funky like that. also, if you do "Thread chase" it, make sure to have the radiator upside down so that all the metal shavings dont end up in there! :D

The rubber isolators are to prolong the life of the radiator by isolating it from vibrations.

Even better, just get a 3/8" npt plug, voila.

Really, aftermarket sensor + woromg

or

npt plug, stock sensor
Doesn't make sensor to use a non stock sensor to me.

That last sentence doesn't make sense to me:beatdeadhorse5:

Damn I can't (well yes I can) believe how cheap you guys are. Spend all this time and effort to try and save a buck if that. I would think your time is worth more. (just busting)

Call Ray and get the sensor 8553-15-610A and gasket 8553-15-611, you are not going to have to worry about it ever again, unless someone overtightens it or breaks the wire off.

Cheap insurance. They have saved many of my customers costly motor jobs over the years. I don't want to have do a motor until it serves a good long time.

That sensor is the earliest warning system that tells you something is going wrong. In the FC3S when it starts going off out of nowhere it is usually giving an indication of the beginning of a housing seal failure.

Both rubber mount points are valid. I prefer rubber mounts. Mazda has used solid mount for so many years 74 to 85. On the point of electrolysis, is long as all of the grounds, wiring and electronic components are good that should be negligible. It will add some protection but if there is any electrical problem it will look to find a ground where ever it can.

TT is that an updraft IC? Just wondered where the air is going or coming from, doesn't look like a lot of clearance between it and the hood when closed.

Its an HMIC and no there is not a lot of clearance between the i-cooler and the hood. Howard Coleman measured the exit speeds form his core @ highway speeds to be about 3-5 mph. I'm sure that little amount of air can find its way out. Its ducted near watertight to the top opening in the bumper. I do plan to drop vent the hood for the i-cooler as well as two other vents specifically for under hood heat. Datalog before and after etc. Right now my IAT's are close to ambient so I'm happy.

As for the low water sensor, I completely agree and plan to put an aftermkt one in my ast as opposed to in the FD WP housing because I just ran ot of pins on my mil-spec connectors far the engine harness

If you are only getting 3 to 5 mph of air speed through the IC that does not seem that there is a lot of air going across it especially at speed. Sounds like most of your air is going through the engine compartment.

Have you thought of using the fender vents for air extraction? It really helps the street cars here in AZ and the Open Road Car doesn't have any heat issues anymore. It spends its life at 135/145 with bursts up to 165 in Texas and Nevada during some pretty warm runs. Haven't thought of checking it but I imagine that the air speed across both radiator and IC are near the same as vehicle speed.
The open road car is so sensitive to any changes in the engine compartment now that we really have to watch what is removed or added now. In the development of the intake air box I neglected to install a four inch square side panel, which was facing the right side oil cooler. The race before the temps were ~195/195. The race with the missing panel, 215 oil 205, water at 145mph. We figured that there was so much air pressure coming out of the air box that it was neutralizing the air flow through the oil cooler. Only change in car to the next race was replacing the missing panel. Temps were ~195/195 again. The car has been flat bottomed to the end of trans with scavenging for the engine compartment also.

We also enclosed the turbo intakes to use ram air from the radiator opening. Intakes in the engine compartment out here lead to short life detonating motors due to high intake temps. Doesn't matter how big your IC is if you are sucking 250F+ into them. Out here we really need to try to get the intake air at least ambient ideally lower.

Before everyone goes they don't have any problems, trying running where ambient is 115F, 0/2% humidity and the street temp is 168/200F. Engine compartment temp 300 in the FD are not uncommon. I have had to develop and race round motors in these conditions for many years. So most of the work has been to make my client's street cars run reliably and perform under these conditions. You guys with 65F and 65% really shouldn't have any heating problems. If you do, something is wrong somewhere.

The GT3 RX7 that I ran would rarely get over 210 oil and water even when ambient was over 120 which there were a few races at PIR and Firebird that did that. When I ran at Sears Point we had to block off a good portion of the radiator and oil cooler to get the thing to temp. Before we did that it would kind of warm up on the grid but by the time I made it down the front straight to that left to go up the hill the temp gauges were buried, to the cold side, I thought I lost the dash electrics. It was the same with the ITA RX7.

I'm sorry, you misunderstood. I didn't measure the speeds exiting the intercooler, Howard Coleman did when he was doing his testing of his stock mounted upgraded really nicely ducted intercooler. Becuase of that test I decided that dropventing the hood wasn't a priority.

I never thought it would be the same as vehicle speed. That would mean that there is no resistance as the air passes through the core. I thought it would be about 1/2 vehicle speed as did most people in the thread on the evil forum. However, one test is worth more than a thousand expert opinions and I'm glad HC tested it. He got 3-5 with an aftmkt core. I'd be curious as to what mine is, not curious enough to buy the test equipment though.

I haven't thought of fender vents mainly becuase in the FC it would be more than a PITA. What I have thought of doing is venting the hood above and slightyl behind the turbos to try to get some of that heat out. When I do that I will drop vent the hood as well. Not becuase it needs it, but becuase every little bit helps. I generally see intake temps about 15-20*F above ambient WITHOUT any additional venting. What is happening though is that when the car sits without any air going through the intercooler core, the core tends to heatsoak. It takes about a minute of driving for the temps to come back down. At the autocross this sunday I plan on opening the hood after every run to help prevent that from happening. When the hood is vented it will be ducted with the core, should help prevent this soaking by isoltaing the core from the engine bay.

On the highway I generally see 175* watertemps, yeah I know, the t-stat isn't even opening. Oil temps are around 175 as well. This has been the case upto about 85-90* ambient temps. Sitting in traffic oil has gotten to 205-210 and water hits 185 before the fan kicks on. Save the incident on the emmisions "dyno" I have never seen temps get above 190* water and 210 oil. Of course it's still only warm here. We'll see what happens in the summer.

Everything has it's own seperate ducts and is ducted nearly watertight. With the exception of the air filters. I left these open but directly in the path of incoming air. The though being that I'd like to use that incoming air, through the headlight vent, to try to keep some airflow in the engine bay and eventually push air out of the vents when they are added.

What I want to do after the ducts are done is tape a few "telltales" and go for a drive and video it. Just to make sure air is being evacuated, and not pulled in. Of course I'll get some logs of water, oil, and IAT's as well.

Boy do I feel like the idiot. Don't know what I was thinking fender vents, thought I was in FD forum. Need to check out Coleman's work, thank you.