Okay I got a 87 Turbo 2 and I had a water pump that failed on me a few weeks ago, I was kinda forced to drive with it as it pissed away coolant, although I did keep it filled everywhere I stopped, but still it would go through a lot. Anyways I replaced the water pump with a new one, and fixed any leaking that had occurred, but I am still getting high temp readings on temp gauge. In fact it will escalate up rather quickly, it all but takes to miles worth of driving to get it up to the half way mark on the gauge, Today it got up to 3/4 while coming into work. So now I am freaked, I've heard what overheating can do to a rotary, so I was pissing my britches to drive the poor thing. But what makes it worse is wondering if it really is overheating or if I am having thermostat failure. I am sure the excessive coolant leaks couldn't be good to any of those sensors. So I was wondering what you guys think, and what your best advice would be in my shoes. I need this car to be running cause work for me as a 40 miles a day of freeway commute, and I don't want to be out an engine.



your responses will be greatly appreciated,



Greg

For starters I would change the thermostat with a Mazda one

and see from there, like $14 from the dealer with the gasket.

Yeah thats on my definite to do list, I was wondering if there are other things that need to be check to like the auxiliary fan sensor or the water temp sensor?



One other question too, I can never seem to get a straight answer from other forums, but would it be worth the investment to replace the stock clutch fan with a flex-a-lite water pump driven fan?? Electrics don't pull enough cfm for my taste but I was curious about the clutchless. Granted it's gonna steal more power away from me, but I am curious if its able to pull more air through the AC condenser and radiator. Any thoughts on this??

Stock fan pulls more cfm than electric ones. To see if you thermostat has failed, which I suspect, when the engine temp is warm feel the upper radiator hose. If its cool and the lower radiator hose is warm then its the thermostat. Regardless do as rob said.

I like the stock fan, when properly functioning its more then adequate.



If you dont know or dont remember when your thermostat

and coolant was changed, then its a good idea to do it.



You can also test a thermostat to see if its working right by

boiling water to a certain temperature, but you

have to remove it, so at that point why bother and just put a new

one in.

Just a couple of other advices when you change the thermostat, check the clutch fan and ensure that it is not worn out or broken. Just give it a spin with your hand and see how long it will spin.........If if spins for a while without stopping it is bad and is not moving enough air to cool your car. I have had this problem before....twice actually. Also when refilling the radiator on a FC I always let it run with the cap off to ensure that all the air is out of the radiator. Too much air can cause false readings on the guage and overheating as well. Since yours is an 87 model there should be a valve on the radiator that you can open and bleed all the air out.



Just a couple other things to think about. https://www.nopistons.com/forums/pub...IR#>/bigok.gif

Heheh I was aware how poor electric fans are, at best you can expect what 3K cfm from them, and the stock clutch fan pulls about 6.5K cfm. I was just wondering how the direct bolt-on flex fans compare, I can never really get a cfm reading for them. But I so hope its not the clutch fan, I've been looking around and the going rate for the clutch unit is a good 181$ USD https://www.nopistons.com/forums/pub...DIR#>/ohmy.png But I'll go ahead and do that test you refered to, Ranzo. as far as air in the system, I had did the radiator cap air bleed when I had to replace the waterpump. As for the thermostat I'm just gonna go pick up a new one at autozone after work tonight, the closest Mazda dealership from where I live is 12 miles away and I already have to put 20 miles on it to get home, and I don't like driving it in this condition any more than I have to, since Autozone is just a few blocks away from where I live.

Do not Use anything, but a genuine mazda thermostat..

ill sell you my clutch fan if you want it, works completely fine too.



kevin.

my baby is in pain https://www.nopistons.com/forums/pub...O_DIR#>/11.gif coming home tonight the car was climbed up to a little over 3/4ths the way on the Temp gauge. I hated it I didn't want to drive it because I know that every second of driving it is killing the engine. When I got home I popped the hood and felt the upper pipe, it was HOT! so I guess the thermostat is working right?? Plus I went a head and tried spinning the fan with my hand, and it spinned pretty freely so I am thinking the clutch had failed. But at any rate I am gonna test out the thermostat. Plus my friend is telling me my radiator needs to be rod out. This **** sucks and I need my car running by the 19th.



1Revvin7 : Please tell me why I should only use Genuine Mazda as opposed to other brands, please support your argument.



teknics: how much are you willing to part with that fan clutch and how soon do you think it will take to send it to me, I live in LA.



Greg

ummm you're in cali right? make me what you think s areasonable offer and if i think its fair ill ship it out right away...i gotta ship some fog lights out soon as well.



kevin.

how is 80$ as a starting point.

80 + shipping sounds fine



kevin

Just to add a few thoughts: The rad fan does little to assist cooling when you're boogying down the highway at speed. Is your temp gauge at 3/4 on the highway, or when you're in stop and go traffic?



I would suspect t-stat issues or a crapped-up radiator if you are getting the high temp readings on the highway at speed.



If the fan isn't doing its job, it will be most noticeable in stop and go driving.

its 3/4 all the time, the guage makes its way up there and just stays there, no matter if I am on the freeway hitting 70 or stop and go, my trip home from work last night, I was on the free way keeping it under 3K on the tach doing about 60mph and it peaked at 4/5ths on the temp gauge, that is when I decided to pull off the 101 and take a 20 minute pit stop, then just took surface streets to get home stopping every 4 to 5 miles to let it cool down, but even after letting it sit, it would all but take two minutes of operation until it pegged back at 3/4ths temp. So freakin frustrating, I got home and tested the upper radiator hose, and it was hot as hell, so I don't know if its thermostat failure, I gave the fan a spin while it was still warm and it would make about 4 revolutions from just one snap of the writst. Right now I am utterly clueless to what is doing this.



This sucks..

Serious?



Because its not a part you want to cheap out on and go with some crappy aftermarket brand.

Okay after hours of work I have come to the conclusion that my engine is bad!

I troubleshooted about the entire coolant system and replaced most of it. Here's what I did

Water Pump = replaced with new

Radiator = replaced with Koyo all aluminum

thermostat = checked operates properly

fan clutch = works properly

AC Condenser cleaned of any debri

engine reverse flushed

brand new coolant (peak pre-mix)

water and engine temp sensors checked for grounding



so far everything here has been done less replacing the sensors. And still it takes the car 5 minutes of driving for the engine temp to raise up to 3/4ths on the gauge. And now I finally noticed white smoke puffing from the exhaust, irratic Idle after the car has warmed up a bit. So I am thinking I have a water jacket leak. Not sure how that makes the engine run hotter than normal, but none the less, I need a professional to look at the car. So My question know is I live in LA near Van Nuys, in the San Fernando Valley area. Is there any reputable rotary experts that can take a look at my car? I'm to the point that this problem is beyond my abilities to troubles shoot or even fix, so now its time to have someone else give a look.



Thanks

Get it pressure tested. If it's running into the block, that test should tell you.

just one question, do you have the big plastic tray under the engine? That directs the airflow through the radiator. just a thought

Just had a brand new thermostat go out on my buddies 7. It had like 2500miles on it.........

An update! I had one of my Nissan friends take a look at my car over the weekend and found out that the fan clutch was dead. It will push air from a cold start but after a minute the fan can be stopped with your hand and actually span the opposite direction of operation while the car is running. So we did a jerry rig test of locking down the fan using a coat hanger wire and witnessed the temp actually going down. So it was the fan clutch after all. I asked another friend about the why would I have problems with temp at higher speeds. He told me that past 40mph your gonna have the same heating issues as a standing idle because the air starts to create a turbulant air pressure zone, he apparently has the same problem with his viper when he goes racing, his temp gauge starts to sky rocket when he hits the straightaways.



Teknics, I think I'll still take you up on that offer for the fan clutch. Send me a pm or email at rotaryman13b@hotmail.com so we can set something up.



Greg

Mad props for doing all that. Its refreshing to see someone actually try to fix the problem. I hesitate to suggest doing all of the things you just did because most will cry it will cost too much but what you just did is exactly what I would have done. You cannot spend enough on your cooling system. I hope your engine is O.K. Got my fingers crossed for you.



Do you have your belly pan on like Ronin asked that does wonders to the cooling at highway speeds.

Nah but I really want to install one, I've been researching this in some books I have been reading and it sounds like it will improbe cooling considerably by creating a higher pressure zone in front of the radiator and ac condensor and the air has no choice but go through the radiator. Is there a company that makes these parts or is it a custom job? Because I its the next thing on my list to do on coolant system (aside from getting a new fan clutch!!)



As far as working on the car, its a breeze, never really worked on engines before, but I grasp mechanical engineering with ease. I used to rebuild and port my own engines when I raced r/c gas cars.



Greg

Are you still using your topmount intercooler?



In my quest to make my car run a cool as possible I have been messing around. I have gone to a FMIC and when I did that I noticed my temp rise. I figured it was the FMIC blocking the radiator. Then I read that the open hood scoop will hurt airflow over the rad. I blocked it off and di one better I raised the back of the hood about 1/8" and pulled the rubber molding sealing it off. Temps dropped at highway speeds noticably.



Get a belly pan - check some junk yards or get some sheet metal and make your own. It is a must do.

I'm still running the top mount, however I do plan converting the car to a front mount, just later on when its economically feasible (heheh oxymoron). But yeah I read somewhere if the mazda engineers had the chance to design the FC's over again they would reverse the scoop and make it cowl inducted. that way you'd get decent air flow through the engine bay but still keep it a low pressure zone so the radiator worked properly. So the FC's originally came with a belly pan!! ahh thats good to know. It didn't have one when I bought the car and I didn't know much about the undersides of these vehicles. Well I got a weekend project ahead of me!



Are there any pick and pull junkyards in the San Fernando Valley that anyone knows about?



Another question, as a temporary fix, I was thinking of locking up the fan clutch by ways of drilling and bolting the inner plate to the outer housing. I don't plan on revving the car high if I do this, but other than that is this advisable as a temporary mickey mouse solution?



Greg

cure to my cooling problems was to run without a thermostat in the summer, temp needle never went more then 1-4mm above the L or C or whatever the hell the bottom mark is. And on mountain cruises with the rotary club, i was the only one who didnt have their heater on trying to circulate the coolant.. =)

Not to be a dick or anything, but there is something wrong with that

rotory club if everyone of them were running THAT hot.

I was told nopt to run mine w/o a thermostat unless I modify something else. I just cannot remember what as I have no intention of doing that.



I always drill a 1/8" hole in my thermostat so any air trapped gets by and does not vapor lock the thermostat.

yeah, the whole club was hitting like more then 80% up their guages. lol, i just stopped using a thermostat and its working fine with and without one, but just my own personal preference is to have no thermostat in the hot ass summer.

An update on my situation. Well I think I got my problem resolved for the most part. I replaced the fan clutch which was completely fubared. So now I have a car that is better tempered. I gets up to about 1/5 on the temp gauge and stays there. even when I give it some stick and push the rpms near redline it was maintaining the temps. I am still curious if this is normal because when I first got that car and right up to before I was having coolant problems the car would barely peak up past the bottom of the gauge. So I am wondering if there is still something going on. I am having some other issues with the car that might be contributing to the problem. (getting bad idle and I think my anti-afterburn system is on its last legs, getting a lot of popping sounds frome the exhaust).





what I was told that running without a t-stat will give your car trouble on cold starts, plus your gas milage and emmissions will be shitty because your car will operate under optimal temp level for a longer period of time. I was told that drilling a 1/8 hole or a bit wider would help out a lot.