The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

  • Join the Community!

    DSMtuners is a massive archive of DSM information - but more importantly, it's a COMMUNITY! Join in and participate with other DSMers, and invite all of your DSM friends to make this place their home. Chat with others, create a build thread, post questions and answers. Get involved! Logging in will also remove many of the advertisements, along with this notice. ;) It will also allow you to view images in threads.

Please Support RTM Racing
Please Support Rix Racing

420A Coolant system issues

Jtdemler

Probationary Member
14
2
Dec 16, 2021
Niles, Michigan
I'll try to keep this as short as possible.

I purchased my "dream" 99 eclipse GS (not big on tuning just love the car for what it is) a week and a half ago, and when I bought it everything was fine, coolant was full and had no problems really didn't check much since I drove it 1hr 45 back home and had absolutely zero issues.

Fast forward to now....

I noticed coolant was low after doing some needed engine bay cleaning. So I took off to the store which is about 13 minutes away but about 3/4 of the way there I notice steam/smoke coming from engine and behind me and temp was going up so I immediately pulled over an shut it off.
Went to open the hood and it was steaming the entire bay and it was coming from (if your standing at the front of the car looking towards the back) the rear right corner-ish of the engine but I'm not sure where exactly that's just what I saw from looking the best I can.

Had someone come rescue me with some coolant and drove it back home zero problems at all. I think I got lucky, also I made sure coolant is topped off and let it idle/steam off everything left on the engine around the "leak" when it overheated for maybe 20 minutes, temp held at normal the whole drive home and while I let it idle. Only reason it overheated was because I'm a dumbass and didn't just put water in for the drive to the store since I've been dailying it since the day it was licensed.

My problem is everytime I took off the radiator cap there was zero pressure at all, even when I squeeze the fat hose coming from the fill cap that goes into the radiator it is completely soft.

I'm still learning how these engines work and hopefully someday I'll know everything. I'm just not sure if it should build pressure like my other vehicles have or if it is different, or is this a red flag that something more serious is going on?


Also if anyone knows why it was coming from that area when it was overheating that would be amazing. And it shows nothing on the codes since the check engine light just comes and goes whenever it wants to.

I can upload some photos is someone would like to see but there isn't really much to show.
 

TK's9d2TSi

Supporting Member
6,250
3,246
Sep 11, 2017
Cincinnati, Ohio
I’m guessing it leaked from somewhere and since it was low on coolant, car started to overheat. When you added coolant, did you let it run for a while before putting the cap back on? If the system had air, the top hose would feel empty since air rises.
 

Jtdemler

Probationary Member
14
2
Dec 16, 2021
Niles, Michigan
When I added more coolant I didn't let it run with the cap off, it took almost a whole jug, then I just put the cap on and drove it home. Next time I go out there I'll take the cap off and let it run for a while like that and top it off if air comes out. Could that be the reason the top hose never gets under pressure? Also whenever I squeeze the hose that goes into the radiator I hear coolant splashing around so I assume there is some air in it.
 

Jtdemler

Probationary Member
14
2
Dec 16, 2021
Niles, Michigan
Ok, so I found that the hose in the picture is the leak.

The picture is from underneath the car. The clamp wasn't even on the hard metal tube it connects to so I readjusted it and tightened it down but i believe it's still leaking since after taking it for multiple drives around the block there's still steam and some drips coming below.

I'm going to buy some new clamps from work today and maybe even see if I can cut the old part of the hose which is a bit mangled and see if there's enough slack to get to new hose.

The hose is in good shape and I didn't notice holes or anything but it could be small, other than being mangled up it's not dry or cracked. I'm also going to see if I can rent a pressure tester to investigate deeper without the engine running and just burning off what leaks.

Also I let it run for a while with the cap off and it released some bubbles but the hose remains soft enough I can squeeze it completely flat even when it's full of coolant but that may be because of the leak.

You must be logged in to view this image or video.
 
Last edited by a moderator:

TK's9d2TSi

Supporting Member
6,250
3,246
Sep 11, 2017
Cincinnati, Ohio
Glad you found it. The hose wont get hard until you run it with the cap on and the system builds a little pressure. If it’s a .9 cap, it’s about 13psi until the cap opens.

When you cut the hose short, make sure it holds on hard acceleration. If it’s too tight and say you have worn mounts for example, it might break or leak after some time.
 
Last edited:

Jtdemler

Probationary Member
14
2
Dec 16, 2021
Niles, Michigan
I'm almost positive that is the leak since it was the only wet hose around that area. Luckily I have another vehicle for the time being so I won't rush anything with it until I know 100% that it is fixed. I'll update you guys after I try some methods and maybe get a pressure tester. Thanks everyone for the feedback
 

dwb

Proven Member
136
52
Sep 9, 2021
Broomfield, Colorado
In your picture, it looks like you might have an oil leak too. Oil will cause coolant hoses to swell, become weak, eventually bursting and causing a leak. Your hose does look a bit swelled right around the clamp. If you're lucky you can just slice off an inch or so from the end and re-clamp it and be good with a slightly shorter hose.

FWIW, here's how I fill coolant: I fill it full, cap it, and squeeze the upper radiator hose several times to get the air moving up, then top off the coolant again and repeat. It helps for the car to be level. I'll then double check the coolant level after it's gone through a heat cycle or two and top off if necessary.
 

Jtdemler

Probationary Member
14
2
Dec 16, 2021
Niles, Michigan
Yeah there is an oil leak, been having trouble tracking it down and it definitely seemed as if the hose was soaked in oil at the end. I'll see if I can cut down to new hose and maybe double hose clamp it. If that doesn't do it I probably have a more serious issue or will need a new hose.
Also I will use your method of filling coolant, I just kinda went with what happened when I filled it next time I do it I'll make sure I do it correctly. I can't explain how thankful I am for this community and the help I'm getting.
 

Mello

Proven Member
1,417
567
Jul 4, 2003
Albuquerque, New_Mexico
If you're having sealing issues after clamping the hose proper, I would bit the bullet & get new hoses & replace. The hose is already deteriorated on the inside & why it's still leaking after redoing the clamp & all.
 

Jtdemler

Probationary Member
14
2
Dec 16, 2021
Niles, Michigan
Yeah I'm not going to screw around with it very much unless it seals well. If not I'm sure, the hose isn't too expensive I don't think, and I don't rely on the car as transportation so I'm ok with waiting for one to be delivered if I can't find it locally.
 

BLACK'98DSM

Proven Member
3,484
1,218
Feb 9, 2019
Alabama
Those 2 hoses are the heater hoses. You can buy them both on RockAuto. I believe I paid around $8 each for mine. The oil leak is probably the valve cover gasket. That is the only part of the engine that would direct oil to the heater hoses.
 

Jtdemler

Probationary Member
14
2
Dec 16, 2021
Niles, Michigan
Okay so I believe I have fixed the issue, the hose I was talking about had a large pinhole that was leaking. I cut as little off as I could and put the hose on with a new clamp. Took it for a drive for about 20 minutes and had zero issues temp was steady and it wasn't leaking. I let the system burp the air out before I took off and tomorrow before work I'll do it again and top it off.

Also, I'll look into the valve cover gasket. Would that be something I could do myself with maybe a friends help or would it be better off left to the "professionals"? I'm totally willing to tackle the job myself.

If anyone cares this is a video of the leak. Not sure how I didn't notice it sooner.

You must be logged in to view this image or video.
 

pieceofcloth

Supporting Member
370
227
Oct 6, 2019
Houston, Texas
If you dont replace that damn hose man, smh. Orielly has hoses by the feet/yard in the back. Theyll cut you whatever. Thats 3-5 dollar piece.

like @TK's9d2TSi had mentioned, with a radiator pressure kit, then you add coolant funnel kit, mannnn.. youd be able to find coolant leaks within the vehicle like wether its leaking from water pump, a hose, if your radiator is cracked etc...and with the funnel, it'll burp itself. Just put it on, filler up and let it go thru a cpl of fan on/offs & you should be good 👌🏼 none of this squeezing hoses and possibly adding more air into the system.

Treat yourself & your dream 99 (it all good maintenance practice)


You must be logged in to view this image or video.
 

BLACK'98DSM

Proven Member
3,484
1,218
Feb 9, 2019
Alabama
I wouldn't try to bend a regular piece of hose and try to use it as a heater hose. You will kink it. Just buy a pre-molded heater hose.

You must be logged in to view this image or video.
 
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned VR Speed Factory

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Top