Coolant Leak Repair

For me coolant leak repair means replacing parts. If the heater core drips on the passenger side floor I believe in replacing the heater core.

So why am I writing about a coolant stop leak product when I never actually poured this stuff into a cooling system?

The answer is although I haven't installed it myself, I've seen vehicles that tried it. Although my customers like me, many of them are in difficult financial positions.

These people become stuck in automobiles far longer than expected. In fact, this is the reason why I started the fix my old ride.com website. 

Nevertheless, instead of taking their cars to me, a trusted mechanic, they find themselves trying low-cost and temporary solutions. The reason I'm writing about the K-seal coolant leak repair additive is because of the reviews on the Amazon website.

Generally speaking, stop leak products don't produce excellent reviews. However, the K-Seal product has more than 670 reviews and an average rating of four stars at the time of this writing.

This is highly unusual for any fluid in the stop leak category. Although I'm writing an article about this product, let me be clear that I have never poured it in myself.

I also do not recommend the installation of this additive without a full understanding of it. With that said, I'll talk about the situations where this coolant stop leak stuff has a better chance of producing the desired results.

K-Seal coolant Leak RepairK-Seal Coolant Leak Repair

What is K-seal Coolant Stop Leak

Whenever you look at the ingredients of these specialized formulas you really won't find any explanation of what's inside.

Therefore, I'm just repeating the propaganda dispersed on their product page. The claim remains that the formulation includes microfibers containing ceramic and copper particles.

The idea is these particles find the leak and then harden to stop it. The product description goes on to explain that the particles bond together when they find the leak.

This stops them from blocking the larger coolant passages throughout the engine, heater core and radiator. In addition, the product makes claims about solving cylinder head gasket failures and water pump leaks.

This is really hard for me to believe and I've never seen any product work on a blown head gasket, because of the high combustion chamber temperatures and pressure.

With that said, I have run into a few people that say they’ve seen success in these areas. I'm saying I haven’t seen an additive permanently fix a head gasket.

I've also never seen it work on a leaky water pump situation, because the pump often leaks from the input shaft seal.

A worn out, water pump allows the spinning shaft to move around. And this prevents the product from hardening to seal the leak.

With that said, if you go to the web page they say it works in these areas. When you start reading through the reviews most of them start out saying they remained skeptical, but became pleasantly surprised.

Whether or not you want to believe these product stories is up to you. In the next section I'll talk about what I've seen when replacing the leaking parts for the customer.

Coolant Leak Repair Additive Results

As I mentioned, some of my customers poured this stuff in and received mixed results. However, they eventually came to see me to have their coolant leak repair done properly.

In the most recent case I got to see how the K-seal additive temporarily plugged several small holes in the bottom of the heater core. You could see the microfibers dried into a resin or glass like substance.

Unfortunately, as the heater core continued to rust, the dried microfiber substance, no longer had a place to hold on to. Therefore, the coolant leak started up again. According to the customer it stopped the leak for about six months.

Here’s one thing I liked about the vehicles I've seen use this. I didn't see any damage. When I use the word damage, I'm talking about the product hardening in the wrong places.

In other words, coolant stop leak products can sometimes reduce the efficiency of the cooling system. This can also increase the repair costs when you eventually decide to fix the car or truck the right way.

As an example, if you pour in the coolant leak repair additive in to stop a heater core leak it might collect in the bottom of the radiator and reduce cooling efficiency.

This turns into a hard-to-find overheating situation. So now instead of just replacing heater core you need to replace the radiator and the heater core. In the next section I'll provide my opinion on where these stop leak products are most effective.

Can Coolant Stop Leak Products Actually Work

People ask me all the time if stop leak products actually work. The short answer is yes. The long answer is more about how long it will last and in what exact situations they’ll stop a coolant leak.

It has a low chance of fixing a coolant recovery tank leak because of the additives they install and the plastic surface. Sealing an intake manifold leak has a better chance of success depending on the location.

As for how long it lasts, I refer you back to the first example. My customer got another six months out of his rusting and failing heater core.

Another major factor to consider becomes the location of the coolant leak. These types of products seem to work best when the leak occurs at the bottom of the individual component.

The ceramic and copper particles wind up settling to the bottom and therefore do their best leak sealing when that's where the leak is. As for the different components that this works on, I can only provide my own personal opinion.

Jeep Heater CoreJeep Heater Core

I would say this stuff has a chance of sealing freeze plug leaks, heater core and radiator issues. It might even fill in deteriorated gaskets in some coolant outlet fittings.

However, if they made this auto part out of plastic the ability of the microfibers to stick to this material seems reduced. As an example, I had a customer with a Chevrolet Cruze antifreeze leak.

They used the K-seal product and it didn't work because the coolant leaked from the plastic housing. I know in tough economic times car owners have no choice, but to put off automotive maintenance and repairs.

If you try a stop leak product just know it might be a waste of $15. Depending on the type of additive you use, it can do more harm than good. We filed the story in the miscellaneous auto repair section. You can visit this area for more hard to classify car repair problems.

Author bio : Mark Gittelman is a retired ASE certified master technician, Chevrolet Professional Service Council member and the founder of FixMyOldRide.com. Watch the video on the about Mark Gittelman page to see his credentials, awards and certifications for yourself. Mr Gittelman hand writes all of the articles on FixMyOldRide.com unless indicated otherwise.