Some of you may remember my thread about putting a new engine in the wife's car. That engine has now developed a leak at the rear core plug (yes the core plug is new). It is in a rather inaccessible place, so I'm considering the use of a stop leak to remedy it. However I don't want to gunk up the heater core or discolor the antifreeze. I was thinking about GM cooling system tabs, but would consider other alternatives... So are there any products out there that would suit my requirements?
Brand of stop leak to fix a leaky core plug
- Thread starter The_Eric
- Start date
- Status
Gm pills only.any other will plug up the heater
Get Bars Leak Gold,its a powder in a tube and easier to use than the tabs which need to be put in the lower hose.
It is ginger root which only expands when exposed to air so core plugging is not a issue.
GM tabs is Bars Leak Gold formed into a tab, same product just a different form.
It is ginger root which only expands when exposed to air so core plugging is not a issue.
GM tabs is Bars Leak Gold formed into a tab, same product just a different form.
I've had great luck with the Bars Leak powder that Trav mentioned. Many times you don't even have to use the reccomended amount, half as much cured a heater core leak in a Saturn.
If stop leak won't stop the leak, an expandable rubber plug might be a solution if you can get the leaker out. (I'm sure there's a real name for the part, but I can't think of it. It's a thick rubber plug with a nut that expands the plug when tightened.)
I once bought a Caprice police car with 150,000 miles on it, and some freeze plugs were leaking. One was a bear to get out even with a bent homemade chisel/punch contraption, and there was no way to install the new one without pulling the engine. I put in one of those rubber plugs and just snugged the nut down now and then for the next 50,000 miles.
I once bought a Caprice police car with 150,000 miles on it, and some freeze plugs were leaking. One was a bear to get out even with a bent homemade chisel/punch contraption, and there was no way to install the new one without pulling the engine. I put in one of those rubber plugs and just snugged the nut down now and then for the next 50,000 miles.
Good to know about the Bars Leak Gold. I have used their liquids with the pellets in it with great success. As the others have said, start with a low dose and work your way up. I had a weeper heater core that I nursed along for 5 yrs using 1/2 bottle doses every 6 months.
Originally Posted By: Rhymingmechanic
If stop leak won't stop the leak, an expandable rubber plug might be a solution if you can get the leaker out. (I'm sure there's a real name for the part, but I can't think of it. It's a thick rubber plug with a nut that expands the plug when tightened.)
I once bought a Caprice police car with 150,000 miles on it, and some freeze plugs were leaking. One was a bear to get out even with a bent homemade chisel/punch contraption, and there was no way to install the new one without pulling the engine. I put in one of those rubber plugs and just snugged the nut down now and then for the next 50,000 miles.
Yeah, the engine would probably have to be disconnected from the transmission and lifted up at the minimum.
So, I got to thinking that the engine started leaking with ~800 miles on it... Why should I pay for the stop leak? It wasn't my work that failed, nor did I have a hand in it. So this afternoon over lunch I went to the parts house/machine shop that did the work and hit the manager up about it. I asked what the warranty was - 12mo/12k miles. Well, the work was done nearing 2 years ago... So even though he really didn't have to do anything, he offered to stand behind his machinist's work and buy the GM cooling system tablets for me.
This reaffirms my belief that being a good customer pays off. I do the bulk of my business with them and try to be a pretty agreeable fellow, even when things don't work out right and thankfully they reciprocated...
Now, that being said, I checked the leak again tonight and it seems to be gumming up so I think I'll just add 2 tabs for now.
If stop leak won't stop the leak, an expandable rubber plug might be a solution if you can get the leaker out. (I'm sure there's a real name for the part, but I can't think of it. It's a thick rubber plug with a nut that expands the plug when tightened.)
I once bought a Caprice police car with 150,000 miles on it, and some freeze plugs were leaking. One was a bear to get out even with a bent homemade chisel/punch contraption, and there was no way to install the new one without pulling the engine. I put in one of those rubber plugs and just snugged the nut down now and then for the next 50,000 miles.
Yeah, the engine would probably have to be disconnected from the transmission and lifted up at the minimum.
So, I got to thinking that the engine started leaking with ~800 miles on it... Why should I pay for the stop leak? It wasn't my work that failed, nor did I have a hand in it. So this afternoon over lunch I went to the parts house/machine shop that did the work and hit the manager up about it. I asked what the warranty was - 12mo/12k miles. Well, the work was done nearing 2 years ago... So even though he really didn't have to do anything, he offered to stand behind his machinist's work and buy the GM cooling system tablets for me.
This reaffirms my belief that being a good customer pays off. I do the bulk of my business with them and try to be a pretty agreeable fellow, even when things don't work out right and thankfully they reciprocated...
Now, that being said, I checked the leak again tonight and it seems to be gumming up so I think I'll just add 2 tabs for now.
You are not supposed to have to use sealer n freeze plugs, but I always do.
Permatex #2 or even silicone RTV.
Somewhat compromises and defeats their function? Probably.
but by far leaking is my concern, not running straight water in winter.
Permatex #2 or even silicone RTV.
Somewhat compromises and defeats their function? Probably.
but by far leaking is my concern, not running straight water in winter.
Last edited:
Originally Posted By: mechtech2
You are not supposed to have to use sealer n freeze plugs, but I always do.
Permatex #2 or even silicone RTV.
Somewhat compromises and defeats their function? Probably.
but by far leaking is my concern, not running straight water in winter.
Agreed, except that I'll use Loctite 271 or 640...
You are not supposed to have to use sealer n freeze plugs, but I always do.
Permatex #2 or even silicone RTV.
Somewhat compromises and defeats their function? Probably.
but by far leaking is my concern, not running straight water in winter.
Agreed, except that I'll use Loctite 271 or 640...
- Status
