i recently changed out my water pump. I took the new pump off of a junkyard car. it looked very new and i have no leaks. however, immediately after i changed it out the car started running hot. the temperature goes up to the tick on the hot side to the right of the middle and stays there, it sometimes fluctuates between that spot on the cold side and that spot i mentioned on the hot side. however i recently changed out the fuel filter and the air filter and put two cycle engine oil in the gas tank because i dont beliece my OMP pump is functioning properly. the engine ran hotter than it ever has the first time i drove it after doing all of these things. i also drained the gas tank to get all of the sludge and build up (of which there was a considerable amount). two things maybe worth mentioning:
-the car ran at the correct temperature (in the middle or slightly to the cold side) at all times before and up to the day i changed the water pump, including a week or two in 80 degree weather. it even ran cool when the car was leaking coolant at a rapid rate (this was right before i replaced the water pump of course)
-the car cut out on me pretty severely on the trip back from colorado. it was hot outside (between 95 and 105 for 10 or 12 hours) it continued to do this but only at 60 miles per hour. never at a lower speed.

weird stuff, someone please help me out. im going to be racing it and i will lose my engine if this problem persists, thanks guys

 

did you bleed the air from the cooling system? do you have the belt tightened properly? are you sure the coolant is topped off? what year is teh car?

 

the car is an 84, i am not familiar with a way to get the air out of the cooling system but it seems to correspond with the amount of strain on the engine. today at 115 mph is when it got the hottest, and im assuming that that is when the engine has the most strain on it. it idles very badly also, worse than it did in colorado. in colorado it idled at about 1100 (we set it wrong i guess) but here it fluctuates between 900 and 1200 every couple seconds. how would i know if i had a bad thermostat?

 

jack up the front of the car and let it run, any bubbles *should* move to the highest point if they were trapped before.

 

oh and run the air on HOT.

 

to check if your thermostat is functioning.. boil it. If it opens it works. Its a real easy process its outlined in the haynes manuel. Also have you tryed adding something called water wetter? It aids the coolent/antifreeze mixture.

 

do i open anything when the front of the car is jacked up? would this problem be associated with cutting out and why did putting in a new air filter and fuel filter accentuate the problem. it went higher than it had before when i changed those out

 

As easily as overheating kills a rotary, why in the hell would you get one from the wreckers and not fork over the cash for a new one? There are some areas you do not take short cuts or cheap out and the cooling system is a biggie. Did you use the old thermostat, or the one that came with the junk pump? Is it an oem thermostat? What was wrong with the old one?

If I sound harsh, good. Don't be stupid and put your entire engine at risk just to save a few bucks. And why would you be driving at 115 mph if you are having cooling issues? Sell the poor car to someone who needs it and will respect it before it's totally toast.

 

Just have the engine warm up with the rad cap off. It will burp itself that way. Just let it sit in driveway while doing this.

 

all righty, and trochoid ure a dick... post something constructive i dont post on these things to hear some guy berate me and give me his personal opinion, just wanted to know how to fix my car ok.

its the oem thermostat.
the old water pump was leaking
i didnt change the thermostat when i changed the water pump (but i have the thermostat from the old pump)
i only replaced my pump with the junkyard pump because the junkyard car had recently been wrecked and the pump was brand new.

 

ok i just parked the car on a really steep hill in my yard and let it run for about 20 minutes. if this is of any consequence, the radiator cap was off and coolant was raising out of the hole. i would put a rag in to soak up what had come up but the level would slowly rise back up to the top again. i capped it and drove the car and the temperature went up again like it always does.

i installed the new water pump twice. the first time i did something incorrectly with the liquid gasket and it leaked. the second time everything went on correctly and there are now no leaks. however, two things: 1. i used alot more liquid gasket the second time, could this be creating blockage within the coolant channels in the engine? 2. i accidently used the wrong kind of coolant as well as the right kind of coolant because we ran out in the middle of the operation. i have since drained and flushed the system. i may have done that incorrectly however. when i drained it i opened the overflow reservoir and it still had coolant in it... how is that drained as well??

 

I don't think with only 4 Post versus 4,484 Post ie trochoid that you have a right to call any one on this forum a Dick.
trochoid always tries to help People here so don't take his comments as being a (Dick) or no one will help you here.
steve

 

what does the amount of posts have anything to do with being able to call someone a dick.if you have a solution to this man's problem then share it..if not ..stfu!!

 

im not going any further into what i said back to trochoid. i didnt deserve that treatment from him, please dont go off on tangents. i just want to stop the overheating so i dont lose my engine. could there be blockage in the coolant channels due to those two things i mentioned?

 

do a cooling preassure drop test. i think thats wat its called. then i would think ur thermo stat is bad. then i would think the waterpump u got was bad.

 

Just a suggestion, switch out the thermostat for a NEW OEM part from mazda directly. Sounds to me like your thermostat is bad, probably not opening. For how cheap one is, its worth it to just change it.

 

Kids.....

 

trochoid isn't being a dick - suggesting new parts with systems as critical as a water pump is sound advice. While his delivery was blunt, he's trying to help you.

 

trochoid just loves and respects the rotary you should to dont be cheap when it comes to the cooling system. even though the parts may look new that dosen't mean that they are good. if your just going to abuse the motor just pull it and send it to me and ill be glad to replace it with a blown one.

 

flushed the system again, refilled w/ correct fluid. still runs hot, it is most likely the thermostat now almost certainly. is there a possibility that the water pump is aftermarket and would require a different thermostat? that didnt sound very probably but thought i would ask.

please only post relavant material

 

After market waterpumps have steel blades (GHB), oem ones are cast. Replace the thermostat with oem only. There is a reason for this if you care to look.

 

last question hopefully,
the reason i agree with those of you who think it is the thermostat is this. please let me know if this assumption is incorrect based on my reasoning. :: when i re-filled the coolant system after flushing i started the car and was going to add coolant as the level drops while the engine warms up. the engine warmed up and got all the way to normal operating temperature (right in the middle of the guage) and it never drew any coolant into the system at all. it stayed right up at the top of the radiator where it was when the engine was cold, even when i pressed the throttle pedal 3 times like the manual instructed. this to me means that the thermostat is not opening and letting coolant into the engine like it is supposed to and the coolant is simply staying in the radiator. the thermostat must open eventually because after some driving the temperature does go down eventually. am i right or wrong in thinking this?