Hasty review K-Seal ST5501 Multi Purpose One Step Permanent Coolant Leak Repair, Blue

GON

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Hasty review of

K-Seal ST5501 Multi Purpose One Step Permanent Coolant Leak Repair, Blue​

Background- discovered I had a very likely heater core leak in my 2004 Lincoln Navigator. All the usual suspects to include windows fogging up and sweet smell in the cabin while the heater was being run. I did a quick check on a heater core replacement on the Navigator, and discovered do it yourself open heart surgery is easier than replacing the heater core on a 2004 Navigator. OOA 2015 I replaced the heater core on my youngest Son's 1998 S10, and the job wasn't bad but one needs a real good back to replace the heater core on the S10.

I did some research, including BITOG, very little write-up, comments on using after-market "magic in a bottle" to fix a leaking heater core. I did find ample writeups on fixing a leaking radiator with magic and a bottle, and to my surprise, a decent percentage as favorable.

The reviews on Amazon are very favorable for Barrs Leak and also K-Seal. I take these reviews with a grain of salt as I know many reviews are in fact fake.

I went with K-Seal only because it was more expensive than Barrs. Barss was $9.99, K Seal 14.99. The Navigator does not offer a way to get into the radiator, and I didn't like the idea of using the coolant overflow, so I noticed the heater hose had a patch in it, so I simply opened up the patch, drained out an ample amount of coolant from the heater hose, poured in the K-Seal.

Drove for about 15 minutes, no longer getting the smell of coolant in the cabin, and the windows no longer fogging up. Let the Navigator sit overnight, took her for a 1 hour drive this cool morning, no fogging of windows, no coolant smell in the cabin. I have no idea how long this will last. I will do a coolant flush in a month, I will be OCONUS for the next few weeks starting Thanksgiving.

Pleasantly surprised. And for note, Prestone sells a flush hardware kit for about $4. I don't want the kit to flush coolant, but it is a great item to cut a heater hose and install a coolant sealer, all parts are in this $4 kit.

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I used bars leaks powder to plug a heater core leak in my 1982 Cimarron. Worked great.

My method was to drain a pint from the radiator, mix the bars leaks with a cup of coolant, and pour it in. I then topped off with the rest of the antifreeze. This ensured that it actually went into the system instead of floating on top. Your method is similarly solid.
 
All of which does not mean that the less expensive Barr's Leak would not have worked just as well. Many people make the mistake of thinking these products will stop head gasket leaks, which they won't. Some make the mistake of adding it to the overflow tank...also won't work.
For block leaks such as a porous casting the correct place to install these are the lower (suction) radiator hose.
Not sure why there is a splice in that heater hose, but someone may have had it blocked off in the past for the same reason.
There is no reason why your fix won't last a LONG time since it seems that you did get it into the correct area of concern.
 
I used bars leaks powder to plug a heater core leak in my 1982 Cimarron. Worked great.

My method was to drain a pint from the radiator, mix the bars leaks with a cup of coolant, and pour it in. I then topped off with the rest of the antifreeze. This ensured that it actually went into the system instead of floating on top. Your method is similarly solid.

I used the bar's leaks tablets to plug a heater core leak in my 1984 Cavalier, which has the same heater core.

I just broke them up so they'd fit into the radiator neck. Then topped it up with coolant and went for a drive and came home to find that one of the oil pressure switches (it has two) started leaking badly. Made a nice mess on my driveway...

Fixed that and it doesn't seem to be leaking coolant from the heater core anymore. But I have a replacement heater core and I will change it at some point.
 
All of which does not mean that the less expensive Barr's Leak would not have worked just as well. Many people make the mistake of thinking these products will stop head gasket leaks, which they won't. Some make the mistake of adding it to the overflow tank...also won't work.
For block leaks such as a porous casting the correct place to install these are the lower (suction) radiator hose.
Not sure why there is a splice in that heater hose, but someone may have had it blocked off in the past for the same reason.
There is no reason why your fix won't last a LONG time since it seems that you did get it into the correct area of concern.
Barr's Leak had outstanding reviews. And there are two different types of Barr's Leak for radiator leaks.

In no way am I suggesting that paying more means a better choice. Maytime's paying more is not the best choice. I just shared what selection I made and why, and I am not endorsing one over the other. The Barr's may have worked even better. But reading all the reviews I could, I went with K-seal.

I didn't expect the "magic in a bottle" to work, and quite happy and surprised it did. Took all of ten minutes plus running the engine afterwards. Now I am wondering if I could have done the same on my Son's S10. Seems almost unbelievable to me.
 
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Any stop leak should be used as directed. After double dosing a radiator leak, I succeeded in plugging the heater core. It was handled by reverse-ing the heater hoses. Yrs later, I managed a htr core leak in a '86 528e with a 1/2 bottle of Bars Leak every 6 months. When I base lined my last used 528e, the coolant was brown. I replaced the water pump when I did the timing belt. I back flushed the system with water until it ran clear. When I pressurized the system, the aluminum radiator sprouted so many pinhole leaks it was comical. The car ran cool on the 50 mile drive home from the elbow of the Cape. Whatever the goop was, (probably Bars Leak, it was 100% effective :cool:
 
Not always a permanent fix, but they do work. Last time I tried to use it, it was for a rusted freeze plug, because Jasper uses steel freeze plugs. I think it kept rusting.
 
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