Hot Rod Forum : Hotrodders Bulletin Board

Hot Rod Forum : Hotrodders Bulletin Board (http://www.hotrodders.com/forum/)
-   Engine (http://www.hotrodders.com/forum/engine/)
-   -   3.4L V6 Firebird loosing coolant... Where? (http://www.hotrodders.com/forum/3-4l-v6-firebird-loosing-coolant-where-217179.html)

maverickmechanic13 03-23-2012 12:09 PM

3.4L V6 Firebird loosing coolant... Where?
 
I have a 1995 Firebird with the 3.4L V6 engine. Car runs and drives fine... However - it looses coolant; but where is it going?

There are no apperent leaks, or puddles on the ground if the car is kept in place, ran and warmed up. Yet, if its driven it slowly looses coolant. The previous owner dumped a healthy amount of sealer in the system, which in my opinion is not a repair. The motor oil is not milky at all and there is no white smoke coming out the tailpipe. The oil fill cap and the valves (as can be seen through the valve cover are clean - not milky). I know these engines are very prone to blowing intake and head gaskets.

I haven't done a compression test, a leak-down test or a radiator pressure test yet. Am i missing something? Does anyone have any input or ideeas?

Thank you.

bigdog7373 03-23-2012 12:43 PM

Head gasket or intake gasket. Are you using coolant or water?

chevynut 03-23-2012 12:58 PM

Quote:

Originally Posted by maverickmechanic13
I have a 1995 Firebird with the 3.4L V6 engine. Car runs and drives fine... However - it looses coolant; but where is it going?

There are no apperent leaks, or puddles on the ground if the car is kept in place, ran and warmed up. Yet, if its driven it slowly looses coolant. The previous owner dumped a healthy amount of sealer in the system, which in my opinion is not a repair. The motor oil is not milky at all and there is no white smoke coming out the tailpipe. The oil fill cap and the valves (as can be seen through the valve cover are clean - not milky). I know these engines are very prone to blowing intake and head gaskets.


I haven't done a compression test, a leak-down test or a radiator pressure test yet. Am i missing something? Does anyone have any input or ideeas?

Thank you.



I think the first thing I would do is pressure check the system and see if you spot a leak while under pressure.

maverickmechanic13 03-23-2012 01:22 PM

Quote:

Head gasket or intake gasket. Are you using coolant or water?
50/50coolant at first, but i didnt wanna waste money on any more coolant so i started adding water. No change - same results. System needs a good flush anyway since there is a lot of copper pellety-looking sealer floating around the radiator.

If it is a bad intake or head gasket, woulnt the coolant end up inside the motor since there is no visible accumulation on the outside or on the ground? If it does end up inside the motor wouldnt it milk the oil pretty quick? The system maintains pressure once the engine is turned off, and stil no leaks. If it were to leak from the head (gasket or a crack even) wouldnt it make the car start harder, or even hydro lock it? Car starts perfectly fine every time...

bigdog7373 03-23-2012 01:28 PM

If it was the head gasket or intake it would burn it. You might not even notice any smoke if its just a small leak.
Another thing to think about is the ratio of water to coolant. Remeber water evaporates when it gets hot. Maybe drain the system and flush out the rad with clean water. Refill it from empty with 50/50. Dont tear it apart before check simple things like that.

LATECH 03-23-2012 03:51 PM

Chevynut wins it. Pressure test the system, if you dont see it escaping from the intake, and it isnt going into the oil , then pull the plugs and crank it over. chances are you'll see it shoot out of a spark plug hole.
Be sure to check the oil to see if it is going there.
Chances are you have an intake leak that is just hard to spot.
Dont rule out a heater core. You will see that dripping from the A/C drain on the evaporator/heater core housing.
check it over good first as those are known for having intake leaks(and head gasket leaks :( )
better to check and find it first BEFORE you tear it down, so you fix it the first time
Chances are the brown crappy looking stuff is degraded Dex Cool, GMs answer for the environment. Unfortunatly it turns to crap and starts to plug stuff up.Flush it well when you get the leak fixed and run good ol glycol.
Be sure to pick a low silicate formula if you can find it.Read the Jug, it should tell you on the back.

oldbogie 03-23-2012 04:07 PM

Quote:

Originally Posted by maverickmechanic13
I have a 1995 Firebird with the 3.4L V6 engine. Car runs and drives fine... However - it looses coolant; but where is it going?

There are no apperent leaks, or puddles on the ground if the car is kept in place, ran and warmed up. Yet, if its driven it slowly looses coolant. The previous owner dumped a healthy amount of sealer in the system, which in my opinion is not a repair. The motor oil is not milky at all and there is no white smoke coming out the tailpipe. The oil fill cap and the valves (as can be seen through the valve cover are clean - not milky). I know these engines are very prone to blowing intake and head gaskets.

I haven't done a compression test, a leak-down test or a radiator pressure test yet. Am i missing something? Does anyone have any input or ideeas?

Thank you.

Check for wet carpet on the passenger side.

Bogie

Shelby1 03-24-2012 08:09 AM

x2 on the intake leak....I have did 3 cars that were identical to this ,a 3.4 and two 3.1s ....all were pulling water/coolant tru cly nearest the driver...intake gasket cured it.
Good Luck!
Kenny

90MJext 03-24-2012 10:59 PM

had the same problem on a 3.8, it wound up being the intake gasket. Check inside the intake, just past the the throttle body. A GM tech told me they are bad about leaking at the gasket.

maverickmechanic13 03-25-2012 08:19 AM

Did some testing yesterday - did a cooling system pressure test, and the system held 16psi like a champ. No leaks at all. I pulled the plugs out to inspect them, all looked ok, no difference whatsoever. Pass. side floorboard also looked ok.

However, when i shined a flashlight down in the valley of the intake, through the injector rail and the plenum, a nice big pool of coolant could be seen (barely, but it was there). I doubt it came from anywhere else but the intake gasket. So for the time being, i think im gonna chalk this one up to bad intake manifold gaskets. Gasket set is about $18, and some new oil and a filter plus some fresh coolant after a thorough flush should do that motor good.

LATECH 03-25-2012 02:23 PM

Be sure to take note of the pushrod lengths when you tear it down(pushrod removal is required) the intakes will be the shorter ones. DONT get them mixed up or ..... :smash: :smash: :smash:
Make a cardboard holder to keep them in order.be certain you dont mix them up, it wont be pretty.


All times are GMT -6. The time now is 03:27 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.