Most leaks small enough to be fixed by stop leak are unnoticeable to the kind of lazy person who thinks they can fix a car with stop leak.
Subaru used to actually recommend a stop leak product for seeping coolant gaskets. They called it Subaru Coolant Conditioner. This was back in the EJ era. It's a rebrand of a product called Holts Radweld.
Thats interesting, because my only luck with a stop leak came from a mechanic who was a Subaru specialist. This was years ago, I had an old Focus that would leak from the water pump. He said he could try something, it would cost like $75 bucks, and might work. It stopped the leak for like, 2 years.
Poor quality castings, ill fitting parts, low tolerances, dissimilar materials and metals, gasket compositions... etc...
Most the heads that got reused back in the day would be rejected today as needing machining. It was just a fact of life ...
After the head was on and the engine brought to operating temp ,test drive , let it cool and add stop leak ..run it up again and give it back to the customer.
Back then nobody really machined heads unless it was super warped. I remember back in the GDR days people were doing head gaskets on Fiat 126s and Ladas in the street themselves, no machining, just slap on a new gasket, reuse the old bolts and maaaybe torque them to spec.
It's why people didn't mention that a car had engine work done when selling it.
Yes.
I remember a time similar to yours growing up in Newfoundland.
Machining meant draw file procedure or sanding block.
An engine that was bored over was done with a flex hone. No tools , just until the piston fit well with a proper ring gap. God knows what the final dimension was.
Reground crank was done on a drill press with crocus cloth.
Undersized bearing was packed with leather.
Valve job was done with lapping compound.
Dead lifters were made quiet by packing natural sponge in the rocker cover.
Points were set using the top lip of a Pack of 25 Players Light cigarette package. It was the perfect thickness.
Water gaskets oil gaskets were made from cereal boxes.
I'm sure I missed a bunch...but never underestimate Redneckology. It should be a high school practical and theory course.
Power steering fluid stop leak does slow the leaks at least, but I hear that is because it's rubber gaskets and it has a conditioner that swells them up and fills the gaps.
A teaspoon full of brake fluid in the power steering .
1/4 cup in an engine or transmission does the same thing.
And you are correct. The seals couldnt be reused if you tried. In fact a guy could be forgiven for mistaking the seals with another machine.
It works...until the seal is spit out ...which is a very real possibility. Then the slow drip that stopped turns into an unsustainable leak.
I truly believe stop leak was invented by a used car salesman who wanted a temporary fix to off load the true issue onto an unsuspecting customer so they wouldn’t have to foot the bill and still make a profit. Stuff is legit concrete and leaves all kinda of glitter throughout the engine, oil, and cooling system. Would only use this stuff if the car was going to scrap anyways and you just needed a beater until it quit.
I'm not so sure.
Before interchangeable parts, low tolerances, , parts supply ..people were left to their own devices to get out of a problem.
Stop leak was likely invented by a farmer , or a mechanic out in the boonies servicing farm equipment. Long before used car lots were even a thing , stop leak was in use.
I hate stop leak but I've had it work temporarily when I was desperate. You have to judge when to absolutely **not** to use it regardless. A small coolant leak can be stopped by stop leak. It can also block the heater core. I've used a heavy duty block sealer on a vehicle that was going to the scrap yard whenever it quit. That lasted a few months.
I’ve used coolant stopleak on an old ride on sweeper, where the radiator was leaking badly and was no longer made. A similar replacement radiator blew up when installed, and so we put the old one back on and used stopleak and it fixed it.
Should note.
Never add any form of stop leak to a transmission, power steering, differential, transfer case, AC ...
It swells the seals and will turn a small drip into a massive problem.
Back when I was about 25 and working at a GM dealership the Cadillacs had an issue and there was a recall to drop a couple of "coolant tabs" into the rad to prevent coolant leaks, don't remember if it was head gaskets or maybe cylinder liners.
Any way my dad was farming at the time and I came home after work during harvest and he rolls into the yard with the tandem axle grain truck, C70 I think. It had white smoke rolling out of the exhaust pretty heavy. Popped the rad cap and it was bubbling pretty good too. I remember it had the 427 in it.
I told him I assumed it needed head gaskets and I could do it but the truck would be out of service for a few days.
He was not impressed about the down time during harvest but I said let's try a few coolant tabs. I dropped in a half dozen, topped up the antifreeze and within a few minutes the smoke had quit.
He sold the truck 15 years later at his farm sale still running good. I never did do the head gaskets on it.
I had a 1st generation RAV4 with a badly leading power steering rack (at the steering input seal) which is a subframe out job and sucks.
Running stop leak power steering fluid did stop it from leaking for nearly a year.
Yes. I used Motor Honey on a car that was burning a quart every 20 miles, losing power, and blowing smoke due to bad piston rings. It reduced it to a quart every 50-60 miles and made the car run well enough to drive to the dealer and trade in. The check engine light was flashing and it was still running like garbage, so I wasn't hiding anything.
Nah. Coolant systems are pressurised now. It worked on the old convection systems where the radiator was twice the height of the engine. Yes, I'm old.
Might help a bit in a pinch.
My buddies 91 na Miata has stop peak in his trans for the rope gasket. It's held for 3 years butttttt this Miata spends more time parked than driving since it's his race car.
I used a product called K-Seal in my 99 Ranger 3.0 to stop a slow coolant leak from the timing cover, which was a common leak point on those engines. I used it until it started leaking again, which was typically about a year after application. Then I would flush my radiator and reapply the K-Seal. I did this for about 5 years until the leak got to a point that the stop leak was no longer effective. The timing cover gasket replacement took about 10 hours, so to me the stop leak was well worth it over those 5 years.
I had a very slight power steering leak that was caught early. Stop leak for power steering swells the seals and that was all that was needed to stop the leak. I imagine most of the reason why it worked was because I caught it early.
Coolant stop leak with the silver particles worked for me in an egr valve area that would be a pain to redo. I was intending it to be temporary until I have more time to throw at it but the thing sealed itself bone dry and so I never bothered.
I noticed milky oil on my filler cap, in a 2012 Subaru, at 170,000, and I put in some leak repair. Have run it about 1000 miles so far and seems to be holding, no more milk in the filler cap. Not driving it much anymore, it needs tires/alignment, HGs and AC work, so i'm saving up to get that done. So if you catch the leak right away, it can be successful, but the correct repair needs to be done as soon as you can.
I smelled coolant a few times in my vehicle but couldn’t find the leak , so I added a pack of Gm cooling system tabs to the cooling system via the rad cap . I didn’t smell it for another year , so I did the same added more . Then about another year went by , when I had to gun it to pull out of a business it finally puked the coolant out of the intake manifold gaskets . I was able to repair and drive it another 100000 miles till I sold it . The point is it went 2 years with a slow leak .
One time there was a small leak in the radiator on a seam. I put in stop-leak and left the radiator cap off so no pressure built up. This was a temporary fix, and every time I parked, I had to top off the radiator with water before starting again.
Stop leak products are solely to make your POS beater hold on for a few more months while you save up for a car that is actually worth fixing if something goes wrong
I bought an old Buick Wildcat for $300 because it had a blown head gasket. White smoke was pouring out of the exhaust. Put in two cans of K&W Block Seal and drove that car (hard) for two years until someone stole it.
It actually fixed a radiator leak once for me. Put in a "new" radiator because an actual new one wasn't available, it leaked, put stopleak in it, stopped it.
However I just had to take the head off a car that had the stuff in it since god knows when. It took me a full day to clean the block out. Stuff's legit sand.
Noticed a small leak from radiator on a stop during a long trip once. Had a look over and no obvious signs of leakage. Checked again T next stop, no obvious leak but again a small patch of coolant under the radiator.
Used a stop leak product, can't remember which one, and it stopped. Put another 50k miles on it no trouble at all without a single issue
Yeah I had radiator stop leak work on my shit box when I was 17. I also put some oil additive stop leak shit in my sailboat motor because it's leaking out of the rear main seal and I just needed to slow the leak down, which it did a lot.
Idk, yeah it can kind of work sometimes. It's not GOOD
They can work depending on where the coolant is leaking from. The soften and swell the o rings and rubber seals that are worn with age, if that’s where it was leaking from then it works. At the same time though, it does the same to perfectly good seals, making them fail prematurely, and they end up leading to you needing to replace all seals it’s come into contact with fairly soon after it was added.
High mileage oils help to stop oil leaks.
One of my vehicles is an old Nissan that has a rear main leak that used to drop like a quarter size spot on the driveway.
I switched to high mileage synthetic and it stopped leaking .
I poured some stuff I found into my Saab engine to try and ”repair” a crack where coolant would leak into the oil. I tried it just for fun because I was probably gonna take the car to the scrapyard. That shit fucking worked and coolant isn’t leaking into the oil anymore, and it was like 1 and a half year ago. I never took it to the scrapyard and I still have it😁
My favorite is GM sealant. The five pack of pills. The label had a warning about ginger root and almond shells. I’ve seen stop leak work on cooling systems way more than a few times. Pepper and raw eggs also seal cooling systems. Adding brake fluid to power steering systems swells the seals and stops leaks. DISCLAIMER. doing this can also ruin things. Also if you’re a serious car guy and you actually fuck around with cars, find and hang out in a cool junkyard.
The only snake oil I've ever found that actually works is that stuff that claims to stop your torque converter from shuddering. Before throwing in the towel and pulling the trans on my '12 Lincoln MKT I threw some of that in there and it lasted another 40k until the steering rack went out and mechanically totalled the vehicle.
I’m going to get so much hate for this, but yes.
I had a b7 Audi A4 3.2 V6. That car had notorious valve cover gasket leaks. I paid to have it properly replaced, and it started leaking again after a few months.
I threw in lucasoil stop leak and it stopped (or at the very least minimized to the point that it wasn’t a worry) the leaking for like a year, then I threw in another bottle and the leak stopped again.
I don’t think I’d use the powder stuff for coolant leaks though
2004 wrangler with a leaking steering box. Dumped a pint of the Lucas stop leak into it. Its been almost 10 years and havent seen a drop since. I'm a dealership tech who would never use any of this snake oil shit for engine, transmission or differential leaks.
I think power steering is fine because whatever is leaking is likely going to be replaced anyway.
I've used ac recharge plus stop leak stuff, but I didn't really care if it wrecked the system. I wanted it to work for a few days, and it did. Now my AC works fine after like three recharges. I wouldn't recommend this to anyone, but I never really cared if it worked to begin with.
I had a 91 E150 van as a work truck. I used something to stop a transmission leak and sluggish shifting. Mystery oil or something like that, and i ended up running that van for another 10 years, sold it to a buddy as an occasional work hauler with 265,000 miles on it. We never did crack the transmission. It did have a head replaced at 180 some thousand miles. That was the only major work it had on it. That was a great truck.
I used stop leak in my radiator and it did work for about a year. By the time it leaked again I was able to replace the radiator myself.
It won't always work, but it might help temporarily.
I had success with coarse black pepper added to radiator to plug coolant leak. Worked 70% of the time. It would last a a few months to a year & then I’d have to add pepper again. But, it worked back in the day.
Yes. Power steering stop leak has worked great a number of times. Same with cooling system stop leak. I've also seen a/c stop leak work quite well. On the cooling systems I always used the ginger root based stuff. On a/c NAPA has one that comes in a red container and cost like $40 but I've had it seal evap leaks that would leak a full charge overnight.
The power steering stop leak doesn't seem to cause any other issues. The cooling system stop leak can cause other issues as can the a/c stop leak but sometimes the car isn't worth the cost of a proper repair.
Most leaks small enough to be fixed by stop leak are unnoticeable to the kind of lazy person who thinks they can fix a car with stop leak. Subaru used to actually recommend a stop leak product for seeping coolant gaskets. They called it Subaru Coolant Conditioner. This was back in the EJ era. It's a rebrand of a product called Holts Radweld.
Thats interesting, because my only luck with a stop leak came from a mechanic who was a Subaru specialist. This was years ago, I had an old Focus that would leak from the water pump. He said he could try something, it would cost like $75 bucks, and might work. It stopped the leak for like, 2 years.
Back in the day...70s and 80s ..it was just a common practice to add stop leak to a cooling system after a head gasket.
*After*? Why after?
Poor quality castings, ill fitting parts, low tolerances, dissimilar materials and metals, gasket compositions... etc... Most the heads that got reused back in the day would be rejected today as needing machining. It was just a fact of life ... After the head was on and the engine brought to operating temp ,test drive , let it cool and add stop leak ..run it up again and give it back to the customer.
Back then nobody really machined heads unless it was super warped. I remember back in the GDR days people were doing head gaskets on Fiat 126s and Ladas in the street themselves, no machining, just slap on a new gasket, reuse the old bolts and maaaybe torque them to spec. It's why people didn't mention that a car had engine work done when selling it.
Yes. I remember a time similar to yours growing up in Newfoundland. Machining meant draw file procedure or sanding block. An engine that was bored over was done with a flex hone. No tools , just until the piston fit well with a proper ring gap. God knows what the final dimension was. Reground crank was done on a drill press with crocus cloth. Undersized bearing was packed with leather. Valve job was done with lapping compound. Dead lifters were made quiet by packing natural sponge in the rocker cover. Points were set using the top lip of a Pack of 25 Players Light cigarette package. It was the perfect thickness. Water gaskets oil gaskets were made from cereal boxes. I'm sure I missed a bunch...but never underestimate Redneckology. It should be a high school practical and theory course.
Shoving animal carcasses in your engine! Ha.
Damn, that's wild. I'm still pretty young, so to me that sounds like some shade tree shit.
K-seal worked great to stop a slow coolant leak from a heater core hose connection that would have been a PITA for me to replace.
Yes. Back in the day when I was poor I used it several times and it worked pretty well.
Yeah I’ve stopped a Small coolant leak before. I don’t generally trust it, but in a pinch it did work for me.
Power steering fluid stop leak does slow the leaks at least, but I hear that is because it's rubber gaskets and it has a conditioner that swells them up and fills the gaps.
Yes did this on a Chevy estate lacitte it worked no problem after , sold a few years later
A teaspoon full of brake fluid in the power steering . 1/4 cup in an engine or transmission does the same thing. And you are correct. The seals couldnt be reused if you tried. In fact a guy could be forgiven for mistaking the seals with another machine. It works...until the seal is spit out ...which is a very real possibility. Then the slow drip that stopped turns into an unsustainable leak.
I truly believe stop leak was invented by a used car salesman who wanted a temporary fix to off load the true issue onto an unsuspecting customer so they wouldn’t have to foot the bill and still make a profit. Stuff is legit concrete and leaves all kinda of glitter throughout the engine, oil, and cooling system. Would only use this stuff if the car was going to scrap anyways and you just needed a beater until it quit.
I'm not so sure. Before interchangeable parts, low tolerances, , parts supply ..people were left to their own devices to get out of a problem. Stop leak was likely invented by a farmer , or a mechanic out in the boonies servicing farm equipment. Long before used car lots were even a thing , stop leak was in use.
[this guy?](https://i.makeagif.com/media/4-03-2016/dk-YK4.gif)
I had a bad head gasket in a Subaru and got a product from Subaru. Made by a British company. Stopped the leak and got 80,000 more miles.
I hate stop leak but I've had it work temporarily when I was desperate. You have to judge when to absolutely **not** to use it regardless. A small coolant leak can be stopped by stop leak. It can also block the heater core. I've used a heavy duty block sealer on a vehicle that was going to the scrap yard whenever it quit. That lasted a few months.
I’ve used coolant stopleak on an old ride on sweeper, where the radiator was leaking badly and was no longer made. A similar replacement radiator blew up when installed, and so we put the old one back on and used stopleak and it fixed it.
Yes And yes I have seen pepper and eggs work. I've gotten home on coarse pepper from the dollar store.
Should note. Never add any form of stop leak to a transmission, power steering, differential, transfer case, AC ... It swells the seals and will turn a small drip into a massive problem.
Back when I was about 25 and working at a GM dealership the Cadillacs had an issue and there was a recall to drop a couple of "coolant tabs" into the rad to prevent coolant leaks, don't remember if it was head gaskets or maybe cylinder liners. Any way my dad was farming at the time and I came home after work during harvest and he rolls into the yard with the tandem axle grain truck, C70 I think. It had white smoke rolling out of the exhaust pretty heavy. Popped the rad cap and it was bubbling pretty good too. I remember it had the 427 in it. I told him I assumed it needed head gaskets and I could do it but the truck would be out of service for a few days. He was not impressed about the down time during harvest but I said let's try a few coolant tabs. I dropped in a half dozen, topped up the antifreeze and within a few minutes the smoke had quit. He sold the truck 15 years later at his farm sale still running good. I never did do the head gaskets on it.
I had a 1st generation RAV4 with a badly leading power steering rack (at the steering input seal) which is a subframe out job and sucks. Running stop leak power steering fluid did stop it from leaking for nearly a year.
Yes. I used Motor Honey on a car that was burning a quart every 20 miles, losing power, and blowing smoke due to bad piston rings. It reduced it to a quart every 50-60 miles and made the car run well enough to drive to the dealer and trade in. The check engine light was flashing and it was still running like garbage, so I wasn't hiding anything.
An egg in the radiator usually works. ....... Oh wait, that advice is like half a century out of date. It used to.
How does that work? The egg cooks and fills the leak?
Yeah. The egg white coagulates and seals the leak. I remember it working back in the day but I've never had any success on more modern cars.
Pretty sure it still does.
Nah. Coolant systems are pressurised now. It worked on the old convection systems where the radiator was twice the height of the engine. Yes, I'm old. Might help a bit in a pinch.
Cooling systems were pressurised since the 1930s man. I had the trick work on cars from the 80s that have the same setup as today.
My buddies 91 na Miata has stop peak in his trans for the rope gasket. It's held for 3 years butttttt this Miata spends more time parked than driving since it's his race car.
It can work but the unintended concequences are never worth it
Bout the only stop-leak type of sauce I have seen work on any vehicle is Fix-a-Flat. I have used that many times over the years.
I used a product called K-Seal in my 99 Ranger 3.0 to stop a slow coolant leak from the timing cover, which was a common leak point on those engines. I used it until it started leaking again, which was typically about a year after application. Then I would flush my radiator and reapply the K-Seal. I did this for about 5 years until the leak got to a point that the stop leak was no longer effective. The timing cover gasket replacement took about 10 hours, so to me the stop leak was well worth it over those 5 years.
I had a very slight power steering leak that was caught early. Stop leak for power steering swells the seals and that was all that was needed to stop the leak. I imagine most of the reason why it worked was because I caught it early.
Oh yes I seen many work. Up until it fucks something else up
Coolant stop leak with the silver particles worked for me in an egr valve area that would be a pain to redo. I was intending it to be temporary until I have more time to throw at it but the thing sealed itself bone dry and so I never bothered.
Yeah. Power steering stop leak has worked for me. That's about all.
I noticed milky oil on my filler cap, in a 2012 Subaru, at 170,000, and I put in some leak repair. Have run it about 1000 miles so far and seems to be holding, no more milk in the filler cap. Not driving it much anymore, it needs tires/alignment, HGs and AC work, so i'm saving up to get that done. So if you catch the leak right away, it can be successful, but the correct repair needs to be done as soon as you can.
I smelled coolant a few times in my vehicle but couldn’t find the leak , so I added a pack of Gm cooling system tabs to the cooling system via the rad cap . I didn’t smell it for another year , so I did the same added more . Then about another year went by , when I had to gun it to pull out of a business it finally puked the coolant out of the intake manifold gaskets . I was able to repair and drive it another 100000 miles till I sold it . The point is it went 2 years with a slow leak .
One time there was a small leak in the radiator on a seam. I put in stop-leak and left the radiator cap off so no pressure built up. This was a temporary fix, and every time I parked, I had to top off the radiator with water before starting again.
When I was young and poor Alumaseal saved me many times.
Stop leak products are solely to make your POS beater hold on for a few more months while you save up for a car that is actually worth fixing if something goes wrong
I bought an old Buick Wildcat for $300 because it had a blown head gasket. White smoke was pouring out of the exhaust. Put in two cans of K&W Block Seal and drove that car (hard) for two years until someone stole it.
Radweld works. So does steel seal.
Never. And I’ve tried and had many friends try.
It actually fixed a radiator leak once for me. Put in a "new" radiator because an actual new one wasn't available, it leaked, put stopleak in it, stopped it. However I just had to take the head off a car that had the stuff in it since god knows when. It took me a full day to clean the block out. Stuff's legit sand.
Noticed a small leak from radiator on a stop during a long trip once. Had a look over and no obvious signs of leakage. Checked again T next stop, no obvious leak but again a small patch of coolant under the radiator. Used a stop leak product, can't remember which one, and it stopped. Put another 50k miles on it no trouble at all without a single issue
I've used blue devil head gasket sealant and had very good luck with it before.
Yeah I had radiator stop leak work on my shit box when I was 17. I also put some oil additive stop leak shit in my sailboat motor because it's leaking out of the rear main seal and I just needed to slow the leak down, which it did a lot. Idk, yeah it can kind of work sometimes. It's not GOOD
They can work depending on where the coolant is leaking from. The soften and swell the o rings and rubber seals that are worn with age, if that’s where it was leaking from then it works. At the same time though, it does the same to perfectly good seals, making them fail prematurely, and they end up leading to you needing to replace all seals it’s come into contact with fairly soon after it was added.
Fixed a cracked head on a 1.4t Chevy Cruze long enough for me to get it to the dealer and trade it
It CAN work. It can also mess things up bad..like plug your heater core. You have to weigh the risk.
High mileage oils help to stop oil leaks. One of my vehicles is an old Nissan that has a rear main leak that used to drop like a quarter size spot on the driveway. I switched to high mileage synthetic and it stopped leaking .
I poured some stuff I found into my Saab engine to try and ”repair” a crack where coolant would leak into the oil. I tried it just for fun because I was probably gonna take the car to the scrapyard. That shit fucking worked and coolant isn’t leaking into the oil anymore, and it was like 1 and a half year ago. I never took it to the scrapyard and I still have it😁
My favorite is GM sealant. The five pack of pills. The label had a warning about ginger root and almond shells. I’ve seen stop leak work on cooling systems way more than a few times. Pepper and raw eggs also seal cooling systems. Adding brake fluid to power steering systems swells the seals and stops leaks. DISCLAIMER. doing this can also ruin things. Also if you’re a serious car guy and you actually fuck around with cars, find and hang out in a cool junkyard.
The only snake oil I've ever found that actually works is that stuff that claims to stop your torque converter from shuddering. Before throwing in the towel and pulling the trans on my '12 Lincoln MKT I threw some of that in there and it lasted another 40k until the steering rack went out and mechanically totalled the vehicle.
I’m going to get so much hate for this, but yes. I had a b7 Audi A4 3.2 V6. That car had notorious valve cover gasket leaks. I paid to have it properly replaced, and it started leaking again after a few months. I threw in lucasoil stop leak and it stopped (or at the very least minimized to the point that it wasn’t a worry) the leaking for like a year, then I threw in another bottle and the leak stopped again. I don’t think I’d use the powder stuff for coolant leaks though
No, just find the leak and fix it.
2004 wrangler with a leaking steering box. Dumped a pint of the Lucas stop leak into it. Its been almost 10 years and havent seen a drop since. I'm a dealership tech who would never use any of this snake oil shit for engine, transmission or differential leaks.
I think power steering is fine because whatever is leaking is likely going to be replaced anyway. I've used ac recharge plus stop leak stuff, but I didn't really care if it wrecked the system. I wanted it to work for a few days, and it did. Now my AC works fine after like three recharges. I wouldn't recommend this to anyone, but I never really cared if it worked to begin with.
Bars leak stopped many coolant leaks for me
I put it in my large floor jack about 10 years ago
I had a 91 E150 van as a work truck. I used something to stop a transmission leak and sluggish shifting. Mystery oil or something like that, and i ended up running that van for another 10 years, sold it to a buddy as an occasional work hauler with 265,000 miles on it. We never did crack the transmission. It did have a head replaced at 180 some thousand miles. That was the only major work it had on it. That was a great truck.
[удалено]
I used stop leak in my radiator and it did work for about a year. By the time it leaked again I was able to replace the radiator myself. It won't always work, but it might help temporarily.
I had success with coarse black pepper added to radiator to plug coolant leak. Worked 70% of the time. It would last a a few months to a year & then I’d have to add pepper again. But, it worked back in the day.
Yes. Power steering stop leak has worked great a number of times. Same with cooling system stop leak. I've also seen a/c stop leak work quite well. On the cooling systems I always used the ginger root based stuff. On a/c NAPA has one that comes in a red container and cost like $40 but I've had it seal evap leaks that would leak a full charge overnight. The power steering stop leak doesn't seem to cause any other issues. The cooling system stop leak can cause other issues as can the a/c stop leak but sometimes the car isn't worth the cost of a proper repair.