Mystery Leak
#1
Supreme Member
Thread Starter
Join Date: Aug 2004
Location: Pasadena, TX
Posts: 1,046
Likes: 0
Received 6 Likes
on
5 Posts
Car: 1991 RS
Engine: 5.0
Transmission: 700r4
Mystery Leak
For the past two months or so my car has been losing water. About a gallon or so and every to days I have to fill it back up. The entire cooling system has been replaced through out the years I have owned it. Water pump twice, radiator, heater core and valve, all hoses, thermostat (currently 160), and thermostat housing. I have looked all over and cannot find any where it might be leaking from. I even put a board in the driveway (gravel) to park over to tell me where its coming from, but to no avail. Something interesting though, the overflow tank has been at the same water level since I noticed the leak. I keep filling up the radiator but the water in the tank never seems to go back into the engine, maybe I need a new cap but I don't see how that could cause such a large leak. Thanks for any help or advice. Chris
#2
Re: Mystery Leak
I'm on my third heater valve. Stupid junk replacements. I'll be bypassing that soon, though.
No smoke, correct? Is the outside of your radiator dry? Before I replaced my radiator, I had a leak that was slow enough to evaporate off before it hit the ground, but large enough to require constant refilling. That's where I'd look first.
No smoke, correct? Is the outside of your radiator dry? Before I replaced my radiator, I had a leak that was slow enough to evaporate off before it hit the ground, but large enough to require constant refilling. That's where I'd look first.
#3
Supreme Member
iTrader: (3)
Join Date: Jan 2006
Location: Flowood,MS
Posts: 1,489
Likes: 0
Received 0 Likes
on
0 Posts
Car: 87 IROC Z
Engine: 5.7 L98 TPI
Transmission: 700r4,2500 stall
Axle/Gears: G80,10 bolt 3.42's
Re: Mystery Leak
Did you make sure the passenger floor board isnt wet?Check the weep holes on the water pump.Did you check the oil for water to see if it was a bad head gasket,It could be leaking on the exhaust side and coming out the exhaust as steam,Had a ford t-bird do that.I had one that leaked at the back of the intake manifold and took forever to locate.Good luck.
#4
Moderator
Join Date: Jan 2000
Location: Mercedes Norte, Heredia, Costa Rica
Posts: 20,981
Likes: 0
Received 9 Likes
on
8 Posts
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Re: Mystery Leak
Get your cooling system pressure tested. It takes about 30 seconds, and i'll show you where it's leaking immediately.
#5
Senior Member
Join Date: Apr 2007
Location: Huntington, NY
Posts: 394
Likes: 0
Received 1 Like
on
1 Post
Car: 1983 Pontiac Firebird
Engine: LG4 305ci 4bbl
Transmission: 700r4
Axle/Gears: 10-bolt open diff.
Re: Mystery Leak
also, take a look at your freeze plugs. one or more may be coming loose and leaking coolant.
#6
Supreme Member
Thread Starter
Join Date: Aug 2004
Location: Pasadena, TX
Posts: 1,046
Likes: 0
Received 6 Likes
on
5 Posts
Car: 1991 RS
Engine: 5.0
Transmission: 700r4
Re: Mystery Leak
Vanilla Sky-it only smokes when I start it in the morning or if its been sitting a while. I may pull the radiator drain it and stick it in a big tub with the cap on and look for bubbles like a tire leak test.
ShadyGrady-the floor is dry i have been constantly checking it. Last time the heater core leaked there was about a half inch of coolant in the floor board. Oil looks fine, just needs to be changed. I will check the back of the manifold like you said. No steam though so I guess no leak on the exhaust side.
Aperion-thats a good idea. Is there some way I can do it myself. I don't have the extra cash for a mechanic. Plus I like to do the work myself.
punkdude908- you may have a good point there. The motor is pushing 200,000 miles and isn't exactly 100%. It's reliable and gets me where I need but for how much longer I don't know.
Thanks for all the help guys and hopefully I figure it out soon.
ShadyGrady-the floor is dry i have been constantly checking it. Last time the heater core leaked there was about a half inch of coolant in the floor board. Oil looks fine, just needs to be changed. I will check the back of the manifold like you said. No steam though so I guess no leak on the exhaust side.
Aperion-thats a good idea. Is there some way I can do it myself. I don't have the extra cash for a mechanic. Plus I like to do the work myself.
punkdude908- you may have a good point there. The motor is pushing 200,000 miles and isn't exactly 100%. It's reliable and gets me where I need but for how much longer I don't know.
Thanks for all the help guys and hopefully I figure it out soon.
#7
Moderator
Join Date: Jan 2000
Location: Mercedes Norte, Heredia, Costa Rica
Posts: 20,981
Likes: 0
Received 9 Likes
on
8 Posts
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Re: Mystery Leak
You can improvise with a pipe bushing, a schrader valve, and a bicycle pump, or you can get the right tool for the job that will pay for itself the first time you use it.
http://store.summitracing.com/partde...5&autoview=sku
http://store.summitracing.com/partde...5&autoview=sku
Trending Topics
#8
Supreme Member
Thread Starter
Join Date: Aug 2004
Location: Pasadena, TX
Posts: 1,046
Likes: 0
Received 6 Likes
on
5 Posts
Car: 1991 RS
Engine: 5.0
Transmission: 700r4
Re: Mystery Leak
Hmm, that reminds me. I have a friend who runs a shop for his dad. He might have one of those. If not I could probably Magyver something. Thanks for the idea Aperion.
#9
Supreme Member
iTrader: (1)
Join Date: Dec 2006
Location: ms. gulf coast
Posts: 2,403
Likes: 0
Received 3 Likes
on
3 Posts
Car: 91 R/S , 89 dodge p/u
Engine: L31 GM crate re-cammed , 318
Transmission: T-5 , 4 speed auto
Axle/Gears: 3.42 , ?
Re: Mystery Leak
most major auto parts stores have the press. testers . you can rent them or they will test for you . usually free . check them out . good luck .
Thread
Thread Starter
Forum
Replies
Last Post