Is there a good stop leak product? My 95 BMW has a heater core leak.
stop leak for heater cores?
- Thread starter Russell
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Don't bother using anything like stop leak. Your best bet is going to be to replace the heater core. They're not much fun to do...plan to spend a good part of a day doing it. Luckily they're usually pretty inexpensive as far as money goes (yikes just looked and they're expensive for your application).
The other thing you can do is if you are willing to give up your heat, either temporarily or permanently, you can bypass the heater hoses under the hood in about 15 minutes. That way you can continue to use the car until you have the time or funds to complete the project.
The other thing you can do is if you are willing to give up your heat, either temporarily or permanently, you can bypass the heater hoses under the hood in about 15 minutes. That way you can continue to use the car until you have the time or funds to complete the project.
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The parts are about $200. My independent BMW shop will charge about $900 or so total to do the job.
I have thought about the heater core bypass. Also it seems that on this model, if you turn the heater completely off not much, if any, coolant flows through the heater core.
I have thought about the heater core bypass. Also it seems that on this model, if you turn the heater completely off not much, if any, coolant flows through the heater core.
It uses a heater control valve so very little if any gets through.
If you are going to try a stop leak product you need to let it circulate until the leak stops
If you are going to try a stop leak product you need to let it circulate until the leak stops
Originally Posted By: Trav
It uses a heater control valve so very little if any gets through.
If you are going to try a stop leak product you need to let it circulate until the leak stops
Good point. Thanks. Turning off the heater only works if I do not replace the leaking core or use a stop leak.
It uses a heater control valve so very little if any gets through.
If you are going to try a stop leak product you need to let it circulate until the leak stops
Good point. Thanks. Turning off the heater only works if I do not replace the leaking core or use a stop leak.
I'll get bashed for saying this, but,
If it leaks, replace it!! Don't use snake-oil, don't be a cheap [censored], just replace the leaky core!
If you really really CBA, at least get the two hoses that feed the core and link them together - NEVER EVER put 'stop leak' products anywhere in your car.
Mechanics fix problems
Cheapskate idiots put bandages over symptoms.
If it leaks, replace it!! Don't use snake-oil, don't be a cheap [censored], just replace the leaky core!
If you really really CBA, at least get the two hoses that feed the core and link them together - NEVER EVER put 'stop leak' products anywhere in your car.
Mechanics fix problems
Cheapskate idiots put bandages over symptoms.
Go for it. But drain 1/2 gallon from the rad. Mix your bar's leak with a quart of coolant, put it in, start it up, let it circulate around, then top off the system with the last quart.
Too many people add stop leak and it floats in the surge tank or on top of the rad, on top of the fins etc inside and it just gunks up the rad cap without going where it needs to go.
I enjoyed 1st hand success on a Cadillac Cimarron that fogged the windscreen on defrost with green fog before the bar's leaks powder went to work.
And... 2 threads on the same subject?
Too many people add stop leak and it floats in the surge tank or on top of the rad, on top of the fins etc inside and it just gunks up the rad cap without going where it needs to go.
I enjoyed 1st hand success on a Cadillac Cimarron that fogged the windscreen on defrost with green fog before the bar's leaks powder went to work.
And... 2 threads on the same subject?
Originally Posted By: Olas
I'll get bashed for saying this, but,
If it leaks, replace it!! Don't use snake-oil, don't be a cheap [censored], just replace the leaky core!
If you really really CBA, at least get the two hoses that feed the core and link them together - NEVER EVER put 'stop leak' products anywhere in your car.
Mechanics fix problems
Cheapskate idiots put bandages over symptoms.
Still on the same kick eh Skyship.
Many manufacturers use these products in brand new engines and recommend their use in their engines.
I don't see the dealers lot littered with clogged cooling systems or heater cores.
The rest of your comments are ludicrous and not even worth commenting one.
I'll get bashed for saying this, but,
If it leaks, replace it!! Don't use snake-oil, don't be a cheap [censored], just replace the leaky core!
If you really really CBA, at least get the two hoses that feed the core and link them together - NEVER EVER put 'stop leak' products anywhere in your car.
Mechanics fix problems
Cheapskate idiots put bandages over symptoms.
Still on the same kick eh Skyship.
Many manufacturers use these products in brand new engines and recommend their use in their engines.
I don't see the dealers lot littered with clogged cooling systems or heater cores.
The rest of your comments are ludicrous and not even worth commenting one.
I've had success with stop leak products over the years. We all know replacing parts is the best way to go but think about it for a moment. $900 to pay a shop or more, and if a person doesn't have the tools, knowledge or plans on getting rid of the car, why not try the stop leak product? The snake oil comments get old after a while. Give it a shot OP, all you have to lose is the cost of the product, and a little time. Some or these products might still come with a money back guarantee. The worst case is you have to by-pass the system or pony up for the repair.
Like Trav said make sure you run the heater full blast after you add the product.
Nice catch Trav!!
Like Trav said make sure you run the heater full blast after you add the product.
Nice catch Trav!!
We would need to know how bad it's leaking to say if stop leak would work. If it's not leaking much, then yes, give it a try.
Originally Posted By: zzyzzx
We would need to know how bad it's leaking to say if stop leak would work. If it's not leaking much, then yes, give it a try.
Not much of a leak. have to add about 1/2 quart every month or so. However, I think it has gotten worse in the past month. Almost broke enough to fix.
We would need to know how bad it's leaking to say if stop leak would work. If it's not leaking much, then yes, give it a try.
Not much of a leak. have to add about 1/2 quart every month or so. However, I think it has gotten worse in the past month. Almost broke enough to fix.
I would think that the odor alone would be enough to want to fix it sooner rather than later. I would just go ahead and try the stop leak.
Originally Posted By: zzyzzx
I would think that the odor alone would be enough to want to fix it sooner rather than later. I would just go ahead and try the stop leak.
Not any real odor-yet. just a whiff every once in a while.
I would think that the odor alone would be enough to want to fix it sooner rather than later. I would just go ahead and try the stop leak.
Not any real odor-yet. just a whiff every once in a while.
Originally Posted By: eljefino
Go for it. But drain 1/2 gallon from the rad. Mix your bar's leak with a quart of coolant, put it in, start it up, let it circulate around, then top off the system with the last quart.
Too many people add stop leak and it floats in the surge tank or on top of the rad, on top of the fins etc inside and it just gunks up the rad cap without going where it needs to go.
I enjoyed 1st hand success on a Cadillac Cimarron that fogged the windscreen on defrost with green fog before the bar's leaks powder went to work.
And... 2 threads on the same subject?
Agreed. I'd go even further and say, if you need a leak stopped on the engine inlet side of the cooling system, completely drain the radiator and add the stop leak to the inlet/bottom radiator hose.
Go for it. But drain 1/2 gallon from the rad. Mix your bar's leak with a quart of coolant, put it in, start it up, let it circulate around, then top off the system with the last quart.
Too many people add stop leak and it floats in the surge tank or on top of the rad, on top of the fins etc inside and it just gunks up the rad cap without going where it needs to go.
I enjoyed 1st hand success on a Cadillac Cimarron that fogged the windscreen on defrost with green fog before the bar's leaks powder went to work.
And... 2 threads on the same subject?
Agreed. I'd go even further and say, if you need a leak stopped on the engine inlet side of the cooling system, completely drain the radiator and add the stop leak to the inlet/bottom radiator hose.
just broke up 4 tabs of the GM product, mixed it with antifreeze/distilled water and added to my overflow/side tank. Drove it about 10 miles/20 minutes on city streets with heater wide open. Hope that distributes it through the system. The plastic overflow tank was brownish,from the stop leak,before I drove and now it is yellowish as before I added the stop leak. FYI,I use G0-5 antifreeze.
Originally Posted By: Russell
Originally Posted By: zzyzzx
I would think that the odor alone would be enough to want to fix it sooner rather than later. I would just go ahead and try the stop leak.
Not any real odor-yet. just a whiff every once in a while.
4-5 tabs should be enough, large cooling systems take 6.
Are you getting any sort of film on the windshield when set to defrost? Wet floor mats or carpet?
Originally Posted By: zzyzzx
I would think that the odor alone would be enough to want to fix it sooner rather than later. I would just go ahead and try the stop leak.
Not any real odor-yet. just a whiff every once in a while.
4-5 tabs should be enough, large cooling systems take 6.
Are you getting any sort of film on the windshield when set to defrost? Wet floor mats or carpet?
Originally Posted By: Trav
Originally Posted By: Russell
Originally Posted By: zzyzzx
I would think that the odor alone would be enough to want to fix it sooner rather than later. I would just go ahead and try the stop leak.
Not any real odor-yet. just a whiff every once in a while.
4-5 tabs should be enough, large cooling systems take 6.
Are you getting any sort of film on the windshield when set to defrost? Wet floor mats or carpet?
I have none none of these issues you mentioned that I can see. However, I do see some coolant/water mix out the AC drain tubes under the car.
Originally Posted By: Russell
Originally Posted By: zzyzzx
I would think that the odor alone would be enough to want to fix it sooner rather than later. I would just go ahead and try the stop leak.
Not any real odor-yet. just a whiff every once in a while.
4-5 tabs should be enough, large cooling systems take 6.
Are you getting any sort of film on the windshield when set to defrost? Wet floor mats or carpet?
I have none none of these issues you mentioned that I can see. However, I do see some coolant/water mix out the AC drain tubes under the car.
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Strange as they are not in the same the same area of the case. There are 3 heater hoses, drivers, passengers and the return.
These IIRC use worm clamps, make sure they are tight. Check all worm clamps for tightness.
Are you sure its coolant coming out of the A/C drain or could it be running down the outside of it?
It is unusual not to get at least a slight film on the inside of the windshield when you have a leaking core.
There is a pipe on the core held by 2 bolts inside the case if this was leaking at the joint it seems possible for it just to leak out the bottom of the case.
The stop leak should have no problem sealing this up permanently, its a corroded core that is more of a problem but they tend to leak badly and fog the inside of the windshield and get worse quickly.
Check the clamps and drive it. I am optimistic.
These IIRC use worm clamps, make sure they are tight. Check all worm clamps for tightness.
Are you sure its coolant coming out of the A/C drain or could it be running down the outside of it?
It is unusual not to get at least a slight film on the inside of the windshield when you have a leaking core.
There is a pipe on the core held by 2 bolts inside the case if this was leaking at the joint it seems possible for it just to leak out the bottom of the case.
The stop leak should have no problem sealing this up permanently, its a corroded core that is more of a problem but they tend to leak badly and fog the inside of the windshield and get worse quickly.
Check the clamps and drive it. I am optimistic.
Originally Posted By: Trav
Strange as they are not in the same the same area of the case. There are 3 heater hoses, drivers, passengers and the return.
These IIRC use worm clamps, make sure they are tight. Check all worm clamps for tightness.
Are you sure its coolant coming out of the A/C drain or could it be running down the outside of it?
It is unusual not to get at least a slight film on the inside of the windshield when you have a leaking core.
There is a pipe on the core held by 2 bolts inside the case if this was leaking at the joint it seems possible for it just to leak out the bottom of the case.
The stop leak should have no problem sealing this up permanently, its a corroded core that is more of a problem but they tend to leak badly and fog the inside of the windshield and get worse quickly.
Check the clamps and drive it. I am optimistic.
Trav, Thanks will check everything tomorrow especially the source underneath. I had a leak in the heater hose area before. It was the aux water pump. replaced and all was good. Does not seem to be the same. However a hose of the heater valve could be leaking. No obvious film on the windows.
Strange as they are not in the same the same area of the case. There are 3 heater hoses, drivers, passengers and the return.
These IIRC use worm clamps, make sure they are tight. Check all worm clamps for tightness.
Are you sure its coolant coming out of the A/C drain or could it be running down the outside of it?
It is unusual not to get at least a slight film on the inside of the windshield when you have a leaking core.
There is a pipe on the core held by 2 bolts inside the case if this was leaking at the joint it seems possible for it just to leak out the bottom of the case.
The stop leak should have no problem sealing this up permanently, its a corroded core that is more of a problem but they tend to leak badly and fog the inside of the windshield and get worse quickly.
Check the clamps and drive it. I am optimistic.
Trav, Thanks will check everything tomorrow especially the source underneath. I had a leak in the heater hose area before. It was the aux water pump. replaced and all was good. Does not seem to be the same. However a hose of the heater valve could be leaking. No obvious film on the windows.
Originally Posted By: Russell
Originally Posted By: Trav
Strange as they are not in the same the same area of the case. There are 3 heater hoses, drivers, passengers and the return.
These IIRC use worm clamps, make sure they are tight. Check all worm clamps for tightness.
Are you sure its coolant coming out of the A/C drain or could it be running down the outside of it?
It is unusual not to get at least a slight film on the inside of the windshield when you have a leaking core.
There is a pipe on the core held by 2 bolts inside the case if this was leaking at the joint it seems possible for it just to leak out the bottom of the case.
The stop leak should have no problem sealing this up permanently, its a corroded core that is more of a problem but they tend to leak badly and fog the inside of the windshield and get worse quickly.
Check the clamps and drive it. I am optimistic.
Trav, Thanks will check everything tomorrow especially the source underneath. I had a leak in the heater hose area before. It was the aux water pump. replaced and all was good. Does not seem to be the same. However a hose of the heater valve could be leaking. No obvious film on the windows.
No apparent leaking from the heater valve/pump area. clamps are tight. Cannot see any leakage under car when parked after driving. Coolant level seems OK. This is after I added 4 tabs of the GM product and drove around with the heater full blast. We shall see.
Originally Posted By: Trav
Strange as they are not in the same the same area of the case. There are 3 heater hoses, drivers, passengers and the return.
These IIRC use worm clamps, make sure they are tight. Check all worm clamps for tightness.
Are you sure its coolant coming out of the A/C drain or could it be running down the outside of it?
It is unusual not to get at least a slight film on the inside of the windshield when you have a leaking core.
There is a pipe on the core held by 2 bolts inside the case if this was leaking at the joint it seems possible for it just to leak out the bottom of the case.
The stop leak should have no problem sealing this up permanently, its a corroded core that is more of a problem but they tend to leak badly and fog the inside of the windshield and get worse quickly.
Check the clamps and drive it. I am optimistic.
Trav, Thanks will check everything tomorrow especially the source underneath. I had a leak in the heater hose area before. It was the aux water pump. replaced and all was good. Does not seem to be the same. However a hose of the heater valve could be leaking. No obvious film on the windows.
No apparent leaking from the heater valve/pump area. clamps are tight. Cannot see any leakage under car when parked after driving. Coolant level seems OK. This is after I added 4 tabs of the GM product and drove around with the heater full blast. We shall see.
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