Leaking coolant

[beastn629]

Ok, I have a little problem. I just installed an Evo 16g on my 1g last night. Install went great and car cranked right up with no problems. So i took it out for a quick spin and on the way back i was coasting to a stop and the car stayed at like 3000 rpms after i took it out of gear. It stayed there for a second or two and then droppped. All the way off. So i cranked the car up again and it did it again. All the way home. So i pulled in the driveway and got out and there was coolant already forming a little stream down my driveway. i got under there and looked and it was dripping out of the bottom of the timing belt cover.

Any suggestions as to what it could be? My first thought was the water pump but i still cant figure out why it wont idle right. The car still had plenty of power it didnt seem to miss or anything like that on the trip home after it started acting up and it was still boosting great.

Thanks in advance for all your help

 

[Colt4G63 also]

It's probably your water pump leaking. The reason for the high idle is probably the temp sensor being dry. The coolant isn't touching the sensor so the ECU gets a cooler reading and revs the engine like a cold start.

 

[beastn629]

ok. that makes sense but what about it just shutting off? it wont stay running unless im giving it gas.

 

[3tcpower]

I would still lean towards the coolant causing it. When my car popped the radiator hose it started running poorly till I fixed it and got more coolant in it. Just my experience.

 

[Colt4G63 also]

If you just installed the turbo, you may have created a boost leak too. After you fix the coolant leak it wouldn't be a bad idea to do a boost leak test at the compressor inlet to check your work. It's never a bad idea to do a boost leak test.

 

[DsM KiD4]

check the O ring that fits on the water pipe behind the turbo. If you didnt replace that with a mitsubishi OEM o-ring then its gonna leak from my experience. I doubt its your water pump leaking just after a turbo swap its more likely its the O ring, but it could be the pump.

 

[beastn629]

Ok homies, Ive got some great news. The messed up idle was due to a clamp, that holds my pcv hose to the intake manifold, dissapearing. (does that sound right?) I plugged the hose back up and cranked the car and it idles perfectly just like it used to. Im guessing it just wasnt used to the twenty pounds it was getting after the 16g install. haha. but i still have that major leak. Im hopin its the water pump but im still not a hundred percent sure. But does anyone know how much it should cost for me to have that replaced? I dont really feel like tackling that job myself for fear of not setting timing correctly and all that. And is it true that when you do the water pump you have to do the timing belt too? Ive done a couple on american v-8's and didnt have to even mess with timing. But i know A dsm is a completly different thing.

Oh and btw thank you very much Colt4G63 for suggesting checking for boost leaks. thats what got me thinking to check for a loose hose.

 

[lo_boost]

Yes. If your going down that deep to the water pump it would be a wise thing to replace the timing belt. It suck, I know but it saves doing doble the work.

 

[Colt4G63 also]

The water pump isn't driven by the timing belt, but you do have to take the timing belt off to swap out the pump so yes, you should change it. especially if it was soaked in coolant. Why take the chance, is the typical path taken on that decision. As the previous poster stated, "If you weren't leaking coolant before the turbo swap, it probably isn't the water pump".

Make sure where it's leaking before you take anything apart. If you don't have a coolant system pressure tester, rent, buy, or borrow one from somewhere (auto parts store or something). It's a pretty simple apparatus that screws on in place of your radiator cap, and allows you to pump up the cooling system to 15psi with a small hand pump. Sometimes you will find a small stream of coolant squirting from one place onto another and fooling you into looking in the wrong place for the leak. Be thorough and use an inspection mirror if need be to see where the coolant actually exits the cooling system. If it's the water pump it would leak from a small weep hole in the pump body, located between the inner and outer pump shaft bearings. If you confirm the leak originates from behind the cover but you can't see where, then pull the cover and pressure test some more. Good luck!

I guess I didn't read your previous post clearly enough, so I should add: If you really don't want to tackle this job yourself, make sure you choose a shop that has experience with 4G63s. Even an experienced tech can goof up the rear balance shaft timing if they haven't done them before. The rear balance shaft only rotates once for every three revolutions of the oil pump sprocket, so you have to take the plug/bolt out of the back of the block and insert a 1/4" extension to ensure proper shaft positioning. Simply aligning the mark is not enough on that particular pulley. It wouldn't be a bad idea to tape your ignition key to that extension before you put it in there to prevent yourself from making a stupid mistake.
Besides that it's a pretty straightforward installation and I'm sure you could get any help you need on here. I don't have a labor guide in front of me, but I'm sure you're looking at somewhere between 3-5 hours of labor for that job (pump and belt), and the belt is minimum $50 for both the timing and front balance shaft belts. Maybe more I don't recall. I kinda think slightly more. I know I paid $130 for my Gates racing belt set from one of my vendors, and didn't use the front belt. A new water pump will cost about $60.

 

[beastn629]

Ok, well what else could be leaking in that area? I know for a fact that it isnt the turbo. and i can see where the coolant is dripping off the bottom of the timing cover.

 

[beastn629]

And when yall say check the o-ring are you talking about a crush washer that goes on the banjo bolt? or is there another o ring around there? i put on brand new crush washers on everything when i did the install.

 

[Colt4G63 also]

No, not the crush washers, the O-ring that connects that big 1.5" pipe that runs from your lower radiator hose to the back of your water pump. If you disturbed it during the turbo install, it could be leaking at the back of the water pump.

 

[beastn629]

Ok, if it is the water pump thats leaking, would it leak all the time, even with the car off? Mine has a slow drip with the car off and when i crank it and have it running it will drip pretty fast, almost a steady stream.