!!!!!!!!!!!!!!!!Overheating!!!!!!!!!!!!!!!!!!

[Rixio]

Short video after an idle warm up...i left it for 5 mins then it started leaking out from the expansion tank grommet

http://www.youtube.com/watch?v=43bdGs4ePlI

Also the pressure check was done yesterday...no leaks at all & they did coolant check...no combustion gasses in the coolant either...:Hammer

[shaunwil]

Very hard to see anything on the pfc, video compression terrible. Sorry im not much help past what you have swapped. Hoe did the guy do the pressure test ??

Shaun

[Grizzly]

Is the Rad hot? also can you put the Thermostat in the wrong way round?

Having that much pressure in the Coolant system that quick i would say it was the engine but if its been tested and comes up good then the only thing i can think of is the water isn\'t flowing through the Rad and so the water in the engine is overheating? but to do this it would have to be a BIG blockage or the Thermostat not opening. If its been tested could it possably be the wrong way round?

This proberly has nothing to do with it but have you drained some of the Water out of the Overflow Tank and while your looking at it make sure the Pipe is still conected inside (its suposed to be submerged in fluid so it does\'nt draw air back into the engine)

I realy don\'t like how Hard the Rad pipes are.

[Grizzly]

The other thing is, Is it getting worse?
Along time ago (collage days) i was told that an engine\'s coolant has to be kept in a sealed environment, Because!! Water if kept sealed will raise the Boiling point, instead of turning to steam/Vapor when it gets to 100deg (which expands more rapidly and causes Bubbles etc Basically unstable), a std Cooling system will take serious heat before get to the point where the Water is just about to turn to steam and the pressure exceeds the cap limit there for loosing its coolant and it Overheats (well over 100deg) But!! if you have a leak so the water does\'nt pressurize and Turns into steam (hard pipes etc) it quickly over Pressurizes the System and then blows off steam.

But also you can get an effect where the wall of the Water seal groove brakes so it does\'nt suck water in but gets the pressure of the Inlet Stroke pressurizing the Coolant like a Compressor, this happens very quickly and i\'ve seen cars that have Cold water being pushed out of the rad cap its that violent, with water seal failures they can go in different places causing different symptoms. At least with a piston engine you get symptoms that can not be mistaken for some thing else (water in oil, oil in water, Exhaust gasses in the water etc) Rotary\'s can have a leaking Coolant seal and you won\'t see any of those.

So what i\'m trying to say is you too leak water out that bad you have to ether rase the Temp to a level where it expands too fast (that can be done if the rad is taken out of the Cooling system). Then you have the leak theory, but for this you don\'t realy need to be seeing masive water loss but you would see it leaking from some where else other than the Overflow tank thats is of cause if it got a new AST cap on. Now you have the pain in the Arse one, the engine pressurizing the System, this would be Ovious if the coolant was tested, its been known for the water seal to still be in place with a peice of the Plates Water seal Groove missing so the symptoms would be mild (as oposed to a proper snapped Seal which you would know about) but it always shows up on a Coolant pressure Test. Another Ovious sign is does it overheat at a Lowish temp (if the cap is\'nt on the Overflow tank does the water coming out of the AST steam? I.e very hot)

[Rixio]

Ok will check that tmrw...pretty sure the thermostat is the right way round as theres only one way it can go by looking at it...

Nop not getting worse, just does it quicker now that the stock ast and stock rad are on...before it could take up to a couple of hours but now its less than 30 mins...im gona put the Feed rad back on tmrw so will check how that goes, also will check thermo and remove the middle section of it...yes the rad does get hot...you can follow the flow on the system when the car is cold from when the thermo opens you can feel the warmth going through the rad into the block then at the throttle and heater matrix pipes etc...so dont think its the wrong wat around...will check the expansion pipe tmrw...but not sure how to make sure if its submerged or not...

P.S does anyone have a pic of which way round it should go just to make sure...it would be reeeeeeeeeeaaaaally embarassing but hey


Edit: Just to add...another person said this earlier "My guess, if it\'s only been 6k since a rebuild, would be a faulty seal to begin with, or it was installed improperly." and the same was said by 2 engine builders in the US...
Now the question is, if this is the cause...Do i trust the builder & take it back...taking his ("Im kind of flexible with this kind of thing") word for it???
Im absolutley not prepared to pay ££££ for it because it happened the same week the warranty ran out!

[shaunwil]

It goes in with the spring loaded disc to the back of the thermostat housing (away from you stood at front of car). There is a corisponding hole it covers once it opens.

Shaun

[Grizzly]

Try putting the Thermostat in a pan of water and boiling it on a cooker, get it realy warm and then turn the heat off and see if its open.

[Grizzly]

Edit: Just to add...another person said this earlier "My guess, if it\'s only been 6k since a rebuild, would be a faulty seal to begin with, or it was installed improperly." and the same was said by 2 engine builders in the US...
Now the question is, if this is the cause...Do i trust the builder & take it back...taking his ("Im kind of flexible with this kind of thing") word for it???
Im absolutley not prepared to pay ££££ for it because it happened the same week the warranty ran out!

Well its a Tricky situation. I would seriously be talking to him at this point (well after the Thermostat is checked ) and tell him the story but don\'t go in all pi**ed off becouse people tend to shut off and you get no where. Alot of the Big engine Builders will relise a Water seal Faliur is not something that can be caused be Missadventure (wacking the boost up) So it could just be a Sick twist of fate or a Bad seal from a Batch?? But it may not be the Builders fault but a bad part. So if your only just out of warantee you may get some Joy if you put your Point accross well.

[Rixio]

Well the thermo is defo in the right way then...Phew (I think:Hammer)

Will check it in the pan tmrw. Also gona ring the builder tmrw and see what he says. Its just the last time i felt like he didnt really want to give me the time of day

P.S I am a nice, diplomatic & well mannered man...most of the time :p

Just updated this aswell...lots of usefull facts on here

http://www.mazdarotaryclub.com/forums/showthread.php?t=30047

[andysmee]

Who\'s the builder? :Laugh But seriously, is it someone we\'ve all heard of?

[Rixio]

Id rather not say at this time...will wait to see what happens first...

[FD3UK]

Not read through all the posts, but do you have the rad caps in the correct position? The non pressure cap fitted at filler point by alternator and pressure cap on the AST. Has the pressure cap been replaced?


Kev

[MillSpeed]

Same here. The fact that that video showed coolant getting pushed out of the expansion tank and you\'re not getting any of the tell-tale symptoms of coolant seal failure would suggest a dodgy AST pressure cap. Has this been replaced?

[Grizzly]

Could be the caps but if thats the case why would the pipes go hard?

Rixio, Does it blow water out all the time (even from cold?) or does it blow water out after a few minutes of being cold?

[Rixio]

Takes around 20 mins to start leaking but itl start at 80\'c now...before i replaced all the pipes and hoses it took up to 2 hours...its very irratic and not consistant to any specific length of time or temp...very strange...

I tested the old and new thermostat and the new one actually opens later & less compared to the old one! Replaced it again with no joy...changed caps again with no joy...

I went to tesco just now, to put some fuel in it as it was almost out and by the time i got back and parked it it was maybe 6 mins? Left it 2 mins then it started leaking...it was also making a very strange hissing noise from around the plenum area which i tried to locate but couldnt because it was dying away slowly...hissing kind of bubbling...

I took a pic a while back of the original thermostat when i pulled it out of the car...it has some sort of silicon or elastic something stuck in the spring...

Also...where can i get some of these nipples from?