wthdidusay82

iTrader: (15)

I only did this earlier today to show someone my car because i couldnt get the flat cap anywhere and im going to have to order one. But I was told by someone else on here that using the pres cap on there wouldnt do anything bad

i also readon on fc3spro.com that you can use a pres cap in place of an unsprung cap, but you cannot usea unsprung cap in placee of a pres cap

i will be getting the cap from mazdatrix asap, i wish there was somewhere else i could get this tho

evileagle

iTrader: (1)

Your local mazda dealership would love to sell you one.

Icemark

any generic radiator pressure cap can be used on the filler on cars that do not have an overflow on the filler.

wthdidusay82

iTrader: (15)

doesnt this increase the system pressure tho ? (is this bad ?)

im going to just get one from mazda unless they dont have them ill get one from mazdatrix

Icemark

No, it has no where to vent to, regardless of if it is a sealed cap or a pressure cap.

Normally on all the cooling system parts I recommend Mazda, however for this cap you can use anything that fits.

BlaCkPlaGUE

lol, I thought that he meant the oil filler, not the coolant filler. So when I read icemarks reply I was like WTF??

wthdidusay82

iTrader: (15)

what do u mean by vent ? i thought it would increase pressure just since it is a pressure cap.. i dont know what u mean by that , sorry im kind of new with the alot of car stuff

i bought a cheap stant radiator cap , but i still have the old mazda one

ill be calling mazda tommorow to see if they have the flat cap in stock

Chris Ng

You don't need a flat cap.. don't waste your money.. I take it that your setup has 2 rad caps.. one on the filler neck, the other on the radiator itself.. your tube for the overflow bottle should be on the radiator side... the cap on the radiator needs to be a pressure cap.. however the cap on the filler neck doesn't care what it is.. You are NOT going to block coolant flow at the filler neck by having a pressure cap on there.. coolant is going to flow no diffrent then if you had a flap cap on there... Sit back and figure out how these pressure caps work, and you'll realize why it doesn't matter what kind of cap you have on the water filler neck...

wthdidusay82

iTrader: (15)

why would they use a flat ap then and not a pres cap ? whats the difference it makes on my system using the pres cap on the filler opposed to the flat ? sorry if it seems i ask stupid questions i just dont understand this at all, i just dont get the concept of why it doesnt matter which cap u use there, i thought u are suppose to use a flat one...i am worried of messin somethin up cuz im using the pres cap and not the flat one

BlaCkPlaGUE

The pressure cap is a valve, it opens at a particular PSI. If it vents on a regular filler neck (without the overflow tube) coolant will spew out from underneath the cap edging. You will lose coolant this way. This is of course assuming that your pressure cap with overflow tube is the same PSI rating as the one without. What I did, on my radiator without the overflow tube, is I put a cap that was rated for a much higher PSI than my mazda one that was on the filler neck (near waterpump housing) with the overflow tube. This ensures that the cap with the higher PSI and no overflow tube on the filler neck, will not exceed the springs PSI in the cap.

Does that make sense now?

If it doesn't, then take two pressure caps of the same PSI and put them on each filler neck, you'll know what we're talking about when you smell coolant after driving...

SonicRaT

iTrader: (6)

Generally because the pressure cap cost more. Pretty much any cap that seals will do just fine, because when the pressure hits and the cap opens, it doesn't have an overflow to go to, so it keeps on pressurizing, even after the spring opens.

wthdidusay82

iTrader: (15)

so i guess the conclusion is i can use the pressure cap in place of the flat cap , if this is all fine im going to test the car tommroow and see if the problem went away or is still there

(coolant boiling/ gurgling after car shut off and temp only at 1/3 not even past half or near it)

wthdidusay82

iTrader: (15)

ok i drove my car for about 10 mins and after only 10 mins the temp was at about alittle under 1/2 way on the gauge

i took the car home and shut it off and i could hear gurgling and then i heard hissing air and found out it was coming from the new stant rad cap that i just bought 2 days ago.

i am assuming the stant caps are bad news, i also am using a pres cap ( stock rad cap) on my filler neck , i dont know if that would have anything to do with the problem

also the cap did not seem like it was turned all the way but it was tightened all the way before i left to drive it

SureShot

If it leaks - it's bad for sure.

wthdidusay82

iTrader: (15)

welll its not coolant leaking out, i just hear air leaking out...but i would assume this isnt good either and would mean its bad ?

xtremeskier97

Yeah..doesnt matter if coolant is leaking out or air is leaking in/out...it's still not good.

Make sure the gasket on the cap is intact and not broken.

wthdidusay82

iTrader: (15)

it also seems like there isnt as much pressure in the coolant hoses on the radiator after i shut it off

where does the coolant go after it goes in the overflow ? my overflow is just about full now from coolant goinginto it after everytime i shut the car off

SureShot

Also - the leak may not be the cap, it could be a problem with the filler neck flange & seat.

wthdidusay82

iTrader: (15)

well the only place i could hear air leakingout after it shutoff was from the cap on the radiator

YearsOfDecay

Do you have a koyo radiator??????? the older ones had a problem with the cap seats being warped... MINE DID.... Took FOR F(*^&(*&ing EVER to get that thing fixed.... Ended up taking it to a shop and having a new neck welded on

wthdidusay82

iTrader: (15)

stock radiator

silverFC

every time i had a problem like that the motor was shot, coolant o-rings or a busted water jacket, but thats just my luck, hope not the same for you

ilike2eatricers

Get an OEM cap and be done with it.

wthdidusay82

iTrader: (15)

coolant or waterjacket better not be shot, this is a brand new rebuilt motor with less than 100 miles on it

because sadly if it is shot ill have to take it out , pay to ship it back to rotary ressurrection and wait for him to take it apart and see what the problem was and if it was my fault my warranty is void (overheating)

IF that were to happened i would be done with my rx7 as i just put about $2500 into it and im not paying for another rebuilt motor when it was just rebuilt.

If coolant seals broke or jaacket it wasnt me that was at fault, the temp was below 1/2 everytime i drove it.

It does smoke idling when i first start it up and until its all warmed up, but it smells like gas to me like its running rich . is this normal ?

edit - caps were ordered today should be here either friday or monday and ill update you on what happens

also - coolant level seems to go down after i shut off car sometimes, and my overflow is like 3/4 full .. one time it was so bad that the overflow was overflowing

RETed

Stant's quality control is nasty.
We went through 3 Stant caps one time (2 were new!), and all of them were bad.


-Ted