Stop leak in the heater core

[Ed Fenwick]

The heater core is leaking. I have bypassed it so it is ok but no heat. Sometimes I want to go up the mountain where it gets cold and need heat. I can't afford to remove the dash to get to the core. My question to you is using a stop leak going to gum up the rest of the cooling system? If ok, what is recommended?
Tks happy new year and God bless Ed

 

[carlthess40]

I’ve used stopleak and many other items
It’s a hit or miss with them and in a heater core , you my have leaves and other tree like stuff in the bottom of the air box just eating away at it. You could give it a try and see what happens. But you do run the risk of clogging up other parts in the cooling paths of the engine.

 

[Ed Fenwick]

I’ve used stopleak and many other items
It’s a hit or miss with them and in a heater core , you my have leaves and other tree like stuff in the bottom of the air box just eating away at it. You could give it a try and see what happens. But you do run the risk of clogging up other parts in the cooling paths of the engine.

Thanks Carl, that is what I was afraid of. What is so small in the cooling system that would be clogged?

 

[carlthess40]

What is called steam holes in the head gaskets. And also the radiator. Some times the fines or tips on the radiators are very small. Ceramic seal works best from Masso
But you need to flush out all the antifreezes before using it
Click on this link. This is what I used when building race engines with all aluminum blocks and heads. The head studs would leak and this stuff would seal it all up and last 4 or 5 race years on a 1000hp plus motor

https://www.summitracing.com/parts/mor-35500/

 

[carlthess40]

This one will work best for you. Same brand but made to be used with antifreeze after you stop the leaks

https://www.summitracing.com/parts/mor-35500/

 

[Ed Fenwick]

Thanks Carl, that can't be shipped to Hawai'i. I'll look around here

 

[swshawaii]

Ed, just in case you can't get the Moroso sealant. Read many positive reviews of K-Seal, and usually stocked at most AP stores.

Do some research and good luck.

https://www.kseal.com/expert-advice/engine-problems/heater-core

 

[Todd Z]

Try Silver solder..... Better then the Mud leak stoppers....

 

[EddieS'04]

Ed, I have had good success with alluma-seal. If it is a small leak. It comes in a plastic tube, under many different brand names. It is an alluminum looking powder. It has never caused any problems with my cooling systems.
I have even used two tubes at a time. Depending on the leak, It has worked for me 7 out of 10 times. Most parts stores have it, for not much $$. GL, Lord Bless you in 2019.

 

[Ed Fenwick]

TKS guys, going to Walmart tomorrow for oil, will look for alumaseal and or Kseal

 

[swshawaii]

If no luck finding K-Seal at WalMart, your local NAPA or O'Reilly's should stock it. Call first.