robtechfabrications

ok so the otherday i was driving home frm the bar and the temp guage was reading pretty high, but then it'd drop right back down...did it a few times...

so what i did was rehook the heater core up (the previous owner disconnected it for some reason) replace the engine to heatercore hose...and for some reason there was no thermostat so i put one in(also i changed the oil/sparkplugs/wires even thought thats not really relevant)

so i ran prestone radiator flush through the system and the temp stayed rock steady where it should be, the heater was kranking out some heat and it went really well while i ran it for the 10 minutes it says to on the prestone bottle.

then following the prestone instructions i drained the radiator and filled it with water and ran it for 10 minutes...heater worked...it went fine...

so i filled it antifreeze/water and started the car...the temp sensor right away read that it was at opperating temp (but the car had cooled off) after a few minutes the temp sensor was reading really hot...so i turned it off...waited about 10 seconds and turned it back on and the temp sensor read normal opp temp....then started reading hot again so i turned it off for 10 seconds again and started it back up and it was still reading hot so i turned it back off...the way the motor was acting was like it hadnt warmed up yet though(the heater wasnt puttin out much if any heat)...so i went around the the motor...it doesnt seem to be leaking coolant anywhere but the hose that connects the top pass side of the radiator to the thermostat was making a chucking sound...like if u had a buncha spit in ur mouth and forced it back and forth through ur teeth on the side...

any ideas what the hell is going on? also the engine compartment didnt feel any hotter than if it was at normal opperating temp...

Funkspectrum

iTrader: (5)

possible clog? maybe your heater core had some gunk in it and fed it back thru the system...

-efini-

you have to keep in mind...fc temp gauges are notoriously inaccurate...

robtechfabrications

should i run another thing of flush through it?

robtechfabrications

but its the temp gauge what do i replace? the sensor? and why would that affect the heater

Funkspectrum

iTrader: (5)

can't hurt...

use an oem thermostat too...

robtechfabrications

hmmm ill do that tomarrow morning

robtechfabrications

i got the thermostat from mazdatrix

-efini-

id also invest in a good autometer or whatever (depending on your budget) water temp gauge...

Funkspectrum

iTrader: (5)

if the gauge still acts up, get an aftermarket one...

deadRX7Conv

I don't understand why you are starting/killing your engine every 10 secs.

Fill engine while cold, allow to fully warm up, allow to fully cool off, top it off, and repeat. Sure, there are shortcuts that can be done.

Sounds to me like you got some air in the system. You never mentioned topping it off everytime you shut it off.

Also, anytime you add straight water to the rad for flushing purposes, you need to make sure you adjust your final refill for any water left in the engine. This is one of the biggest mistakes with backyard do-it-yourselfers. They flush with water a couple of times, refill with 50:50 coolant which unknowingly causes a not good 25:75 mix of mostly water.

You should also be using an OEM thermostat.

Which prestone product did you use? quart size or pint size? radiator cleaner or radiator flush?

And, some people disconnect the heater core when it LEAKS. If that is the case, you need to bypass or replace it. Sorry, there is no reason not run a heater core and no reason not to have a thermostat. Sounds too fishy!

-efini-

well actually, the both of you lol ^^ good calls..

robtechfabrications

one that hooked up to the stock sensor? or one that uses its own? (never used aftermarket guages so i dont knwo how they hook up)

theagavejazz

iTrader: (4)

there might be air in the system. check it out and bleed it good.

-efini-

i dont think it matters...its the guage it self thats shitty if i remeber correctly, they only have 3 positions... low/normal/your fucked. cuz they dont start to move untill its too late.

robtechfabrications

yea seemes fishy to me too...i have the oem termostat from mazdatrix...and when i filled the 50/50 coolant i did add more coolant cuz i do knwo about the water in the engine...but you're right i didnt top it off every time (i didnt start and then turn off the car every 10 seconds...it'd take a few minutes for the temp to rise like that and i'd turn it off) and i used prestone super radiator flush

robtechfabrications

i read when the heatercore leaks it gets the passanger side carpet wet and you can spell the coolant...neither of those 2 things have happened yet and i've checked the passangerside for ANY wetness at all many time...while it was working the flush through i checked it constantly

robtechfabrications

alright i just went out...tops it off with antifreeze...the heater was crankin out heat for about a minute then it just started blowing air...and after 5 minutes the temp gauge went up to 3/4 (opp temp is at 1/2) im gonna wait for it all to cool and then see if it needs ot be topped off again...im probably just making somethign out of nothing...im just a lil paranoid cuz i've heard rotaries are finicky and this is my first one

deadRX7Conv

Glad you compensated for residual water in the block during your ratio adjustment.

I would not do another flush.

What I would do is bypass the heater core and see if problem goes away.

Make sure that you have a new radiator cap to allow the cooling system to siphon coolant from the recovery bottle during cooling. And, make sure that the hose from the recovery bottle doesn't leak.

Another options which I hate and don't recommend are the radiator sealer tablets. Find some at your local GM dealer. Subaru also has a cooling system additive to reduce/clog/prevent leaks.