MSP Overheating...Guru help needed

[daedalus]

Excuse the novel, but i wanted to include every detail while it was still fresh in my mind. Thanks in advance for anyone who actually takes the time to read this!

Okay, so i have a Greddy catch can acting as a coolant catch tank for the time being. I blocked off the bottom, and ran a coolant hose in it down to the bottom to act as a "straw" so it could suck coolant in and push it out. Went for a little drive to test my theory. Lately, it would drive fine for about 20 minutes of constant running, then start spiking the temp gauge quickly up to about 3/4 temp and then settling. Didn't seem to be consistent whether i was driving or sitting still. Now in theory, my setup should be fine for cooling right? It doesn't matter if the actual container has holes at the top preventing a closed off container does it? Maybe affecting the vacuum effect?

So back to the drive. All was fine, popped the hood, and the straw had fallen out of the catch can (i had just stuck it through a hole in the top of the can), so i put it back in and all was dandy until about 5 minutes later sitting at a stop light and the temp gauge started to flicker higher. It went a couple ticks higher, then would resettle at half temp until i got home and backed the car into the driveway on an incline (car facing down the slope) and then the temp gauge spiked to 3/4. Fans were on, the straw was securely in the can. I shut the car off, then cycled the ignition back on and kept it on for the next 2 minutes to see if the temp would creep back down. It did not.

Figured screw it, i'll throw it back in the garage. Turned the car back on (had been sitting for about 2 minutes with the hood open) and the temp is sitting back at half like normal.

What the hell gives? Heres the catch! I am running a GM Temp Sensor hooked up to my temp gauge on the dash due to the Microtech essentially killing the temp gauge on installation (it takes the input rather than the dash). Sooooo, maybe the sensor is bad? It just doesn't seem logical to me that the water temp could actually fluctuate that quickly, but at the same time i'm scared to trust that. Thinking it might be the sensor, i jiggled the wires on it before i started it backup in the driveway while the ignition was on, but it didn't seem to affect the temp readout on the dash.

The exhaust did not smell of coolant. There was some "smoke" out of the tailpipe on startup after it had been sitting for over a week, but thats normal condensation in my book.

You guys got any ideas? Anyone with the Microtech care to chime in?

Thanks a bunch guys! (headbang)

 

[Dpwhitehead1]

i don't have a microtech...but my guess sounds like your t stat is bad or the sensor...if you have something that's not meant for the cars..that's ify upon working correctly.does the coolant boil, smoke anything?

 

[daedalus]

Coolant made a gurgly sound when the car was off, almost like a boiling sound i guess.

 

[Dpwhitehead1]

Coolant made a gurgly sound when the car was off, almost like a boiling sound i guess.

do you have a stock radiator? i know when my radiator went, i had that happen.

 

[daedalus]

do you have a stock radiator? i know when my radiator went, i had that happen.

Yea, stock radiator. Is there anything I can do to confirm these symptoms? Verify that coolant is boiling?

 

[Dpwhitehead1]

Yea, stock radiator. Is there anything I can do to confirm these symptoms? Verify that coolant is boiling?

hmm...run it and stop, to check? i don't know. i'm by no means guru, i just know that happened..the GM sensor if not stock, could be an issue too... i'm trying to think of other things...like, addatives you might have used, which cause bad things...

 

[daedalus]

hmm...run it and stop, to check? i don't know. i'm by no means guru, i just know that happened..the GM sensor if not stock, could be an issue too... i'm trying to think of other things...like, addatives you might have used, which cause bad things...

We'll now that you mention it, the catch can used to be full of oil... i tried cleaning it thoroughly, but upon me putting the straw into it, i found there was still some oil grime inside of it. Maybe thats gunking things up?

 

[Dpwhitehead1]

We'll now that you mention it, the catch can used to be full of oil... i tried cleaning it thoroughly, but upon me putting the straw into it, i found there was still some oil grime inside of it. Maybe thats gunking things up?

could very well be. oil mixing w/ coolant..going through the motor-bad.

 

[daedalus]

After doing some searching on here, it allmost sounds like i might have air in the cooling system... Will draining the system and refilling it have a better chance of removing all the air from the system as just pumping the hoses with the radiator cap off while its running?

Might explain the gurgling noises i was hearing and why the car reacted differently once i put it on an angle if there was air up in the head of the engine.

 

[Velocifero]

Are you losing any coolant anywhere? even a small amount? I too have a catch can as my radiator overflow, only mine is Weapon R, and here is my theory to the guys doing the straw technique. It is a usable method but when you look at the logistics of the can and if there was a problem this is what you will see. First a quick explaination of the resevior. It is there to catch the overflow of fluid when the engine heats up/ cools down and readily adds back to the radiator when needed. Under normal everyday functions this straw technique works just fine, due to the vacuum created by the moving coolant in the radiator. This is a pressurized system though, if something was to occur and you were to lose that vacuum, say you had a air leak at your rad cap, the fluid will still move through but you lose that vacuum. Only now there is no vacuum to pull that extra fluid back into the radiator because it was only vacuum fed. Now if you look at the OEM overflow resevoir design (and how I set up my WeaponR can) you can see that the radiator gets fluid back by not only the vacuum created but also gravity. So in this case you lose fluid and it is pushed back in by gravity. In the other case, no vacuum no coolant pull, I assume there is a site glass on the can? Have you opened the radiator cap to ensure there was fluid in there, regardless of there being some in the site glass on the can?

That is just my take on it. There are other reasons your temp is rising, such as Tstat, sensor, possibly even the water pump, but I think you would see leaking with that.

 

[daedalus]

I was leaking fluid out of the can up until today when i blocked it off finally. The system doesn't have any leaks now (that i could visably see) unlike last week where the can was just overflowing and leaking all over out of a hose connection.

You make a great point with the vacuum, and i'm afraid to say it, but i think stock might be better in this application. I'm ordering the stock resovoir and cap from montogmery mazda as we speak, trying to track the sensor P#, and i'm going to try and drain the system, change out the reservoir and sensor and see where that gets us.

It was a long time ago, but all was good until i swapped out the stock reservoir for the greddy. That was the night the car overheated and i've been trying to piece things back together since then.

 

[Velocifero]

I was leaking fluid out of the can up until today when i blocked it off finally. The system doesn't have any leaks now (that i could visably see) unlike last week where the can was just overflowing and leaking all over out of a hose connection.

You make a great point with the vacuum, and i'm afraid to say it, but i think stock might be better in this application. I'm ordering the stock resovoir and cap from montogmery mazda as we speak, trying to track the sensor P#, and i'm going to try and drain the system, change out the reservoir and sensor and see where that gets us.

It was a long time ago, but all was good until i swapped out the stock reservoir for the greddy. That was the night the car overheated and i've been trying to piece things back together since then.

you could even leave the can in there, just tap the bottom of it so it is gravity fed. But there is nothing wrong with reverting back so you can make sure you eliminate that as the problem.

 

[Wbriggs19061]

i agree with Velocifero on the tapping for gravity feed..on a different note i put a stage4 clutch in a neon srt4 and the guy had a 20oz pepsi bottle wedged between the ac lines as his overflow...im sure if his was working with that..then there must be someway to get the catch can to work lol

 

[daedalus]

you could even leave the can in there, just tap the bottom of it so it is gravity fed. But there is nothing wrong with reverting back so you can make sure you eliminate that as the problem.

It actually was tapped at the bottom as a gravity feed, it was simply just Radiator outlet > bottom of catch can. The rest was closed off, but probably not air tight. Still had the problem with it setup like that.

 

[Velocifero]

It actually was tapped at the bottom as a gravity feed, it was simply just Radiator outlet > bottom of catch can. The rest was closed off, but probably not air tight. Still had the problem with it setup like that.

because it still needs an open hole at the top. even the oem has a venting hole/ over over flow port. but I dont think the can is really the problem. i think going back to stock will help you eliminate it as the potential problem. I also don't know how air could be running through it unless you were completely empty, the coolant pick up is at the bottom of the radiator. And besides that isn't it the coolant vaporized while inside the block and cooled back to a liquid via the radiator.

 

[dEd hOm E]

you're thinking of freon(a/c refrigerant). engine coolant remains in liquid form until the boiling point is reached, at that point you're already overheating the engine.

And besides that isn't it the coolant vaporized while inside the block and cooled back to a liquid via the radiator.

 

[Jaysanooch]

I think you should change your thermostat and rad cap....and go from there. I really doubt it's the catch can or having old coolant causing it overheat that much.

 

[wicked]

sounds like you have one of two things going on here.either you have a bad thermostat(sticking closed)or you have a air pocket.
it wouldn't be a bad idea to change your therm,since it's real easy/cheap.
and you can take car of any trapped air at the same time.

I HIGHLY recamend you have a shop do this they can put your cooling system under vacuum so as to get ALL air out.

 

[Dpwhitehead1]

i have a stock reservior i believe....

 

[Rush]

Okay, so I read through this -- and there's one thing I'm still not entirely clear on.

Matt, is there a 'vent hole' in your current coolant catch can? Or is it air-tight?

I was running an air-tight coolant catch can for awhile -- basically because I'm stupid, and I thought I'd drilled a vent hole in the can when I actually hadn't. I realized something was wrong not when I started overheating -- but when I started smelling burning coolant through my vents while driving. Turns out that the upper radiator hose and the hose that leads back into the catch can were spluttering coolant all over my engine -- BECAUSE I didn't have that vent hole, and the backpressure was forcing the coolant to splutter out elsewhere. That air hole is vital to let the coolant seep back into the catch can. Y'know?

So if you've been running without that vent hole, and your coolant has been sputtering out -- have you seen any leaks? smelled anything? -- then that could be causing your overheating.

Even tho' my MSP never overheated (by some miracle of God), but that's the only suggestion I have. (boom02)

And Velocifero -- where did you tap into the Weapon R tank for a gravity feed? I already did the straw setup, but there isn't any 'extra hole' to tap in on the bottom on my tank, unless I actually drill something myself. Any pics?