Water leak at firewall
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Car: 92 RS camaro, 99 Z-24 cavalier
Engine: 5.0L TBI, 2.4L
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Water leak at firewall
After I few weeks I have pinpointed the water leaking into the passenger side is coming from the firewall area in the engine bay. I was planning on using some sort off rubberized caulk to try and seal the area. The problem is getting to it. It appears to be leaking just under the black cannister (thinking its A/C condenser) on the passenger side. Probably at the seam where the wheel well is.
What Im wondering is can I just unbolt that thing (looks like only 2 screws) and have enough slack in the ac lines to move it away enough to get a caulk gun in there? Or will I have to bite the bullet and have the ac lines drained the unhook it from the lines ? Car is 92 RS V8.
Or if anyone has a good idea to repair that area im open to suggestions.
What Im wondering is can I just unbolt that thing (looks like only 2 screws) and have enough slack in the ac lines to move it away enough to get a caulk gun in there? Or will I have to bite the bullet and have the ac lines drained the unhook it from the lines ? Car is 92 RS V8.
Or if anyone has a good idea to repair that area im open to suggestions.
#2
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Re: Water leak at firewall
not sure what black canister you're talking about, the ac condenser is in front of the radiator. pics would help greatly.
I just cut out a bunch of rotted metal in that area and welded in new metal, seam sealed it all, and also found water to be coming in from random ports in the firewall that wires feed through. the rubber grommets dry out and let water in.
If you're gonna use any sealant I highly recommend automotive seam seal, comes in a caulk gun tube at autozone for $15. It's actually very good seam seal despite being an autozone brand.
I just cut out a bunch of rotted metal in that area and welded in new metal, seam sealed it all, and also found water to be coming in from random ports in the firewall that wires feed through. the rubber grommets dry out and let water in.
If you're gonna use any sealant I highly recommend automotive seam seal, comes in a caulk gun tube at autozone for $15. It's actually very good seam seal despite being an autozone brand.
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Car: 92 RS camaro, 99 Z-24 cavalier
Engine: 5.0L TBI, 2.4L
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Re: Water leak at firewall
Your right sorry about calling it the condenser, I'm not sure what it's called. Let me upload a pick of my engine it should have the same setup as the rs I'm working on.
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Car: 92 RS camaro, 99 Z-24 cavalier
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Re: Water leak at firewall
You can kinda see that canister at the far left of my engine bay with the yellow sticker on it in the first pic. Hers is leaking right under there.
#6
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Re: Water leak at firewall
The thing with the yellow sticker on it is called the "heater" box (just a generic term).
Typically, the box is bolted and sealed to the firewall. The leak might be the box seal.
Typically, the box is bolted and sealed to the firewall. The leak might be the box seal.
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Car: 92 RS camaro, 99 Z-24 cavalier
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Re: Water leak at firewall
Why does the box have refrigerant labels on it? My main concern was loosing refrigerant but if there's none in there I'll go ahead and pull it out. I sprayed water underneath it with a hose. It seems like it's under it but it's a ridiculous tight fit.
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Re: Water leak at firewall
So this is an actual pic of the thing that is in my way. I removed the only 2 bolts that look like they held it to the wall. It didn't move at all, I m hoping there aren't any bolts that have to be taken out from the interior. The leak is for sure coming from that area though.
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Re: Water leak at firewall
That round section has room inside the HVAC (Heater, Ventilation & Air Conditioning) box for the squirrel cage fan that is on the end of the blower motor. You can see the end of the motor sticking out of that box...the black metal part with the electrical connector on it.
The yellow decal is factory, and warning you that inside that HVAC box is not only the heater core, but also the air conditioning evaporator. The hoses for both the heater core and a/c evaporator attach to fittings that pass through openings in the box. In other words, if you chose to remove the whole box, those connections will all have to be undone. Which means the a/c system will have to have the refrigerant drained from it. Hence the warning label in yellow. The blue label is simply telling you that the a/c system has been converted from R12 to R134A.
Now, what you can and can't take off from under the hood, and in what order do you do that? There I can't help you.
The yellow decal is factory, and warning you that inside that HVAC box is not only the heater core, but also the air conditioning evaporator. The hoses for both the heater core and a/c evaporator attach to fittings that pass through openings in the box. In other words, if you chose to remove the whole box, those connections will all have to be undone. Which means the a/c system will have to have the refrigerant drained from it. Hence the warning label in yellow. The blue label is simply telling you that the a/c system has been converted from R12 to R134A.
Now, what you can and can't take off from under the hood, and in what order do you do that? There I can't help you.
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Re: Water leak at firewall
Are you losing coolant at all?
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Car: 92 RS camaro, 99 Z-24 cavalier
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Re: Water leak at firewall
That round section has room inside the HVAC (Heater, Ventilation & Air Conditioning) box for the squirrel cage fan that is on the end of the blower motor. You can see the end of the motor sticking out of that box...the black metal part with the electrical connector on it.
The yellow decal is factory, and warning you that inside that HVAC box is not only the heater core, but also the air conditioning evaporator. The hoses for both the heater core and a/c evaporator attach to fittings that pass through openings in the box. In other words, if you chose to remove the whole box, those connections will all have to be undone. Which means the a/c system will have to have the refrigerant drained from it. Hence the warning label in yellow. The blue label is simply telling you that the a/c system has been converted from R12 to R134A.
Now, what you can and can't take off from under the hood, and in what order do you do that? There I can't help you.
The yellow decal is factory, and warning you that inside that HVAC box is not only the heater core, but also the air conditioning evaporator. The hoses for both the heater core and a/c evaporator attach to fittings that pass through openings in the box. In other words, if you chose to remove the whole box, those connections will all have to be undone. Which means the a/c system will have to have the refrigerant drained from it. Hence the warning label in yellow. The blue label is simply telling you that the a/c system has been converted from R12 to R134A.
Now, what you can and can't take off from under the hood, and in what order do you do that? There I can't help you.
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Re: Water leak at firewall
Wouldn't it be possible to remove the squirrel fan and seal it from the inside?? (I never had my fan out)Just a thought
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Re: Water leak at firewall
Is the condensent drain plugged causing all this??? Or IS it antifreeze in the pass area. 2 different things could be going on here.
Just my
Just my
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Re: Water leak at firewall
I did remove it to give me some more room, but where its leaking is directly below it I believe. when I sprayed alittle water below it then I could see it steadily running to the inside.
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Re: Water leak at firewall
does anyone know where I can get the seal for the blower motor box?
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Re: Water leak at firewall
Where exactly are you getting the water???? How much water is getting in? Could the water be coming from a bolt hole from the heater box? Sometimes when people replace them they don't put all the bolts back in, and I've read on here about people getting water when the bottom PITA one is not put in. I don't know, never had that issue, but that's what I read. So, don't take my word for it, but worth a look. Now, if it's coolant, than it is probably your heater core, which is right behind that box under the dash.
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Re: Water leak at firewall
box to fire wall w/o ac, I have contacted oer and classic industries neither of them have it any thoughts would be or great help. may just buy some 1/8 inch rubber gasket off ebay and try that but original would be nice.
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Re: Water leak at firewall
I used that dyi gasket (kind of like thick paper) crap from pep boys and gasket sealer on mine. Are you sure it's a seal and not a screw hole that doesn't have a screw in it? The bottom screws can be a B#*& and I have heard of people getting water in the passenger footwell area because the screws weren't reinstalled.
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Re: Water leak at firewall
I used that dyi gasket (kind of like thick paper) crap from pep boys and gasket sealer on mine. Are you sure it's a seal and not a screw hole that doesn't have a screw in it? The bottom screws can be a B#*& and I have heard of people getting water in the passenger footwell area because the screws weren't reinstalled.
#23
Re: Water leak at firewall
I got up close to the passenger seat it is always wet there. why is that? water also leaking down from behind passenger side kick panel? can someone help?
#24
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Re: Water leak at firewall
If its just water coming from outside the car, there is a fairly inexpensive fix for this.
Its not a "professional" fix.
I paid professionals to work on my water leak.
I think they may have put a dent in the leak, but they sure as hell didn't fix it.
There are two particularly troublesome spots where RUST will allow pinholes (or gaping holes) to form, which will result in water coming in to your car.
One is the cowl-bowl that is formed by the firewall and a bowl-sort-of-shaped piece of stamped sheet metal. The repair that follows is for the cowl-bowl only.
The other is the roof-line just below the drip rails. That's a whole other issue, and I'm happy to talk about that in another thread if you discover the roof-line is the issue.
If you have gaping holes behind your dash, you need to get in there and patch them with something rigid. These holes will be in the firewall which serves as part of the "bowl" of your cowl drain.
I didn't have gaping holes. I had pinholes.
Here is how I fixed (still holding after a year) the pinholes:
First, remove the carpet from the passenger area.
You cannot work over top of a sponge.
Buy the following at home depot.
Run water down the cowl bow, and work the drain tool to dislodge any clods that may have formed in the cowl drain. Be sure work both sides.
Pour half the quart of acetone slowly down one side of the cowl bowl, and work the drain tool. Pour the rest of the acetone down the other side and work the tool. The acetone de-greases the inside of the cowl bowl.
Let dry for 24 hours.
The cowl drain is now as clean as you are likely to get it.
Pour half of one can of Rustoleum down one side of the cowl bowl.
Now -- HERE IS THE SECRET -- Use a LEAF BLOWER to blast the Rustoleum all over the place inside the cowl drain. Pour the rest of the can down the other side, and blast it with the leaf blower. I used an empty 12-pack soda carton to form an improvised nozzle-funnel to channel the air-blast from my leaf blower into the narrow area of the cowl bowl. Used duct-tape to reinforce the soda carton nozzle funnel. That leaf blower really gets it on when you force the air through a funnel hole not much larger than a quarter.
If you contort yourself so you can see up under the dash, you will see Rustoleum paint coming through the pinholes. The Rustoleum will clog the pinholes to varying degrees.
Allow the first quart of rustoleum to dry for a few hours.
Best to do this job on a day that is hot and dry. Paint doesn't dry quickly in cool or damp weather.
You now get the picture of what the Rustoleum does, and you now know how to get it to the areas that need it. Repeat the process as many times as it takes to get the Rustoleum to stop coming through your firewall. When no more Rustoleum will penetrate the firewall, water won't come through anymore either. At least no time in the near/foreseeable future.
This worked great for me.
Alternatively, you can "do the job right." Pull the motor, and pull the dash, and mount the whole uni-body on a rotisserie, and soda-blast the whole thing, cut out any rot, and tig-weld patch panels into all the voids.
That was too-tall an order for me.
I already owned a leaf blower, and the rest of the materials cost about $30.
If you are concerned about the Rustoleum clogging the side-drains for the cowl, put your mind to rest. The Rustoleum is too thin to do do that. The paint just runs right out the drains in the same manner as water. If you have some sort of constriction in the drain, and the paint won't run out, use a length of stiff wire (coathanger?) and/or your drain tool to dislodge any clogs. I didn't encounter any clogs in my project.
I will assume you understand that you need to fashion some sort of collection receptacle to collect the paint that runs out the drain. I used a short cardboard box with a trash bag and some paper towels in it. A lot of the paint will stay in the cowl and will migrate around to plug holes. This is the objective.
Let us know how it all works out for you.
Its not a "professional" fix.
I paid professionals to work on my water leak.
I think they may have put a dent in the leak, but they sure as hell didn't fix it.
There are two particularly troublesome spots where RUST will allow pinholes (or gaping holes) to form, which will result in water coming in to your car.
One is the cowl-bowl that is formed by the firewall and a bowl-sort-of-shaped piece of stamped sheet metal. The repair that follows is for the cowl-bowl only.
The other is the roof-line just below the drip rails. That's a whole other issue, and I'm happy to talk about that in another thread if you discover the roof-line is the issue.
If you have gaping holes behind your dash, you need to get in there and patch them with something rigid. These holes will be in the firewall which serves as part of the "bowl" of your cowl drain.
I didn't have gaping holes. I had pinholes.
Here is how I fixed (still holding after a year) the pinholes:
First, remove the carpet from the passenger area.
You cannot work over top of a sponge.
Buy the following at home depot.
- one drain-clean tool (the $5 three-foot plastic thing with plastic barbs on the side that you cram down your sink drain to pull hairballs out of the drain without taking the trap apart).
- one quart of acetone
- three quarts of Rustoleum black paint
Run water down the cowl bow, and work the drain tool to dislodge any clods that may have formed in the cowl drain. Be sure work both sides.
Pour half the quart of acetone slowly down one side of the cowl bowl, and work the drain tool. Pour the rest of the acetone down the other side and work the tool. The acetone de-greases the inside of the cowl bowl.
Let dry for 24 hours.
The cowl drain is now as clean as you are likely to get it.
Pour half of one can of Rustoleum down one side of the cowl bowl.
Now -- HERE IS THE SECRET -- Use a LEAF BLOWER to blast the Rustoleum all over the place inside the cowl drain. Pour the rest of the can down the other side, and blast it with the leaf blower. I used an empty 12-pack soda carton to form an improvised nozzle-funnel to channel the air-blast from my leaf blower into the narrow area of the cowl bowl. Used duct-tape to reinforce the soda carton nozzle funnel. That leaf blower really gets it on when you force the air through a funnel hole not much larger than a quarter.
If you contort yourself so you can see up under the dash, you will see Rustoleum paint coming through the pinholes. The Rustoleum will clog the pinholes to varying degrees.
Allow the first quart of rustoleum to dry for a few hours.
Best to do this job on a day that is hot and dry. Paint doesn't dry quickly in cool or damp weather.
You now get the picture of what the Rustoleum does, and you now know how to get it to the areas that need it. Repeat the process as many times as it takes to get the Rustoleum to stop coming through your firewall. When no more Rustoleum will penetrate the firewall, water won't come through anymore either. At least no time in the near/foreseeable future.
This worked great for me.
Alternatively, you can "do the job right." Pull the motor, and pull the dash, and mount the whole uni-body on a rotisserie, and soda-blast the whole thing, cut out any rot, and tig-weld patch panels into all the voids.
That was too-tall an order for me.
I already owned a leaf blower, and the rest of the materials cost about $30.
If you are concerned about the Rustoleum clogging the side-drains for the cowl, put your mind to rest. The Rustoleum is too thin to do do that. The paint just runs right out the drains in the same manner as water. If you have some sort of constriction in the drain, and the paint won't run out, use a length of stiff wire (coathanger?) and/or your drain tool to dislodge any clogs. I didn't encounter any clogs in my project.
I will assume you understand that you need to fashion some sort of collection receptacle to collect the paint that runs out the drain. I used a short cardboard box with a trash bag and some paper towels in it. A lot of the paint will stay in the cowl and will migrate around to plug holes. This is the objective.
Let us know how it all works out for you.
Last edited by W.E.G.; 09-09-2017 at 07:13 PM.
#25
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Re: Water leak at firewall
Just a few quick thoughts...
There are two or three places water can enter the car under the dash. The first question is if the water is anti-freeze. If the inside of the windshield fogs up with the defroster on, or if the carpet under the passenger's side of the dash is under an iridescent green ocean, or just anti-freeze drips, it's coming from the heater core.
If the water isn't anti-freeze, consider that it could be condensation from the Air Conditioning system. Normally condensation SHOULD drain in the engine compartment. If the drain hole gets plugged, eventually it could leak inside the car. It'd be unusual but it's possible.
If the water is rain water entering from outside, it's most likely coming thru an existing hole, or it's getting thru a seam that was originally sealed. That can be a gap between panels, a leaky rubber grommet, or the butyl around the windshield leaking, etc. So start by inspecting existing seals. I'll attach a few photos of the firewall with everything removed to show existing holes and seams. In the photos, you'll see a rusty area around the hood release cable. One place this car was leaking. It was also leaking in the corner behind the cable, where the factory seam sealer had cracked and failed, letting water enter between the panels. On the passenger's side, it was leaking at the corner next to the ECM harness hole and the antenna hole, again from seam sealer that had failed.
The seam sealer used on thirdgens was never intended to last 30 years. Even when it looks ok, it's frequently dried out, cracked, and pulled away from one side or the other of the joint. Sometimes the only way to tell it's failed is to pick it loose and you'll see the dirt or rust behind it.
FWIW.
There are two or three places water can enter the car under the dash. The first question is if the water is anti-freeze. If the inside of the windshield fogs up with the defroster on, or if the carpet under the passenger's side of the dash is under an iridescent green ocean, or just anti-freeze drips, it's coming from the heater core.
If the water isn't anti-freeze, consider that it could be condensation from the Air Conditioning system. Normally condensation SHOULD drain in the engine compartment. If the drain hole gets plugged, eventually it could leak inside the car. It'd be unusual but it's possible.
If the water is rain water entering from outside, it's most likely coming thru an existing hole, or it's getting thru a seam that was originally sealed. That can be a gap between panels, a leaky rubber grommet, or the butyl around the windshield leaking, etc. So start by inspecting existing seals. I'll attach a few photos of the firewall with everything removed to show existing holes and seams. In the photos, you'll see a rusty area around the hood release cable. One place this car was leaking. It was also leaking in the corner behind the cable, where the factory seam sealer had cracked and failed, letting water enter between the panels. On the passenger's side, it was leaking at the corner next to the ECM harness hole and the antenna hole, again from seam sealer that had failed.
The seam sealer used on thirdgens was never intended to last 30 years. Even when it looks ok, it's frequently dried out, cracked, and pulled away from one side or the other of the joint. Sometimes the only way to tell it's failed is to pick it loose and you'll see the dirt or rust behind it.
FWIW.
#26
Supreme Member
Re: Water leak at firewall
When I was doing the leaf-blower/rustoleum/cowl thing I used the cheap throwaway sponge "brushes" to push more rustoleum (from the inside - up under the dash) into the spots where I could see rustoleum poured in the cowl seeping through the firewall.
In my opinion, seam sealer is too thick in viscosity to easily reach, or penetrate, to the areas up under the dash where there are pinhole leaks.
The right way to do it would be to pull the whole dash out and fight it from a clean slate. Big job to get the entire dash assembly out, and maybe not necessary (or even completely effective) if the issue is pinhole leaks coming from the cowl bowl through the firewall.
I guess it just depends on how far you want to go with the issue.
In my opinion, seam sealer is too thick in viscosity to easily reach, or penetrate, to the areas up under the dash where there are pinhole leaks.
The right way to do it would be to pull the whole dash out and fight it from a clean slate. Big job to get the entire dash assembly out, and maybe not necessary (or even completely effective) if the issue is pinhole leaks coming from the cowl bowl through the firewall.
I guess it just depends on how far you want to go with the issue.
#27
Member
Re: Water leak at firewall
You found where it is leaking through, but you gotta trace it to how it got there at stop it at the source. The cowl area is the biggest PITA of all (in my opinion). Your talking the windshield, the engine, the entire dash and electronics. Not for the faint of heart.
The important thing is you getting in there and stopping the water leak before it does any further damage to the car. (You would be shocked at how many people ignore it)
Wherever there is water getting in, rust is usually not far behind. (Unless you are one lucky SOB)
I wish you luck
The important thing is you getting in there and stopping the water leak before it does any further damage to the car. (You would be shocked at how many people ignore it)
Wherever there is water getting in, rust is usually not far behind. (Unless you are one lucky SOB)
I wish you luck
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