Small antifreeze leak from bottom of harmonic balancer

[WileE]

Would adding a stop leak help any….

It "could"... years ago, I gave up working on a Mitsubishi leak, what a freakin' nightmare. The only job I ever gave up on in my life. I put stop leak in there, told the owner give it a try to see if it works, before I have to tear the whole front off on the dual-cam engine. It worked. But, as another said here, diagnose it and do the repair, it's not difficult on these cars.

 

[bm02tj]

If it is the water pump seal that will not help

 

[Steven Bowers]

A lot of people take the seal out with pure antifreeze as they measure in antifreeze then add water or seal is rotated dry
If it continues to leak only option is replace pump

I pulled everything off today….I got my mirror and flashlight and INDEED you can see where the antifreeze was coming out of the weep hole onto the bottom bolt and going down the lower pulley and balancer…..I figure guys this is the original pump….all kinds of stampings on it…..anyway making my way over to the parts store…..I greatly appreciate all of you guys input……

 

[Steven Bowers]

Found the leak was coming from weep hole…new one purchased today…..thanks for all your help fellas….

 

[bm02tj]

Mix your antifreeze with water before adding
Good luck

 

[Kern Dog]

I have installed the pump bolts without a sealant and had leaks.

 

[Steven Bowers]

I have installed the pump bolts without a sealant and had leaks.

I made sure to add gasket seal to the bolt threads….it should not have leaked thru the head of bolt…new gasket and sealer….anyway for the age of my pump I’m most likely just better off with a new one….

 

[Steven Bowers]

Okay guys we still have a leak on my new pump….got the charger out again driving around my neighborhood….got it in driveway ….turn motor off…after say 5 minutes I notice a small drip….got my flashlight and mirror out and found the leak is coming from the bottom bolt….NOW it is not coming from the bolt head….it is between the pump and pump housing….took radiator cap off and releasing the pressure it seems to have stopped…now I used a gasket along with mega grey o.e.m. High temperature silicone on pump housing and the pump itself and put the gasket in between…obviously I need to take this off again and reapply the goods….can I forget about using the gasket and apply this mega high temperature silicon very liberal and see if that works….my first application I only just ran a little bit of this stuff and smoothed it out with my finger…my bet is the lower part of my pump housing has a low spot and needs a excessive amount of silicon applied to fill this low spot in…what do you think….on top of my issues I just installed a thermo fan clutch and go figure it doesn’t work….as the say goes just cause it’s new doesn’t mean it’s gonna work….The good news is I got to drive Big Blue around the neighborhood again….been 5 years….I also have the bolts torqued to 30 lbs…..

 

[bigorange426]

NO stop leak, change out the water pump, also check thermostat housing and heater hose connections t

 

[Old Sparky]

Okay got my 69 Charger started today…on the road finally in 4 plus years…my question is why I have a small drip of antifreeze leaking from the bottom of the pulley / balancer….not to sound too ignorant but does coolant go behind the timing chain plate…..is there a seal that may be dried out….I’m open for some possible solutions….it did not have this leak prior to my refresh detailing I’ve done to it….had the water pump, pulleys fan and radiator all off for detailing….torqued all the bolts down to proper specs…..all new gaskets as well…Fel Pro

Water pump shaft seal....replace the pump

 

[MelroseMopar]

You didnt by chance upgrade to a chrome thermostat housing did you? I have never had one that didn't leak with just a gasket.

 

[diesel_lv]

He has since fixed this on another thread.

 

[RJRENTON]

After sitting a long time the ceramic seal will leak and if you are lucky it will heal itself
put some miles on it and keep checking

Simple cartridge type carbon vs ceramic single unbalanced mechanical seals do not heal themselves. In this case, the stationary half, the ceramic element is leld in place with an elastomer that can crack. The rotary seal face is held by an O-ring and compressed to the ceramic stationary seal with a spring. Again the O-ring can fail and leak or crud in the coolant can damage the seal faces causing a leak. The most common failure is the shaft bearing going bad, causing runout at the seal faces resulting in a leak. The coolant is the actual lubricant for the seal faces. If the seal is leaking coolant from the weep hole.....don't wait.....replace the pump....it will only get worse. Just my opinion of course.
BOB RENTON

 

[kbfallon]

Thanks, I’m happy to hear it’s not from a seal, or timing plate….I really hate to take my pump back off and redo it….I put all new gaskets and put some gasket sealer on thinking this combo would work well….I figure it’s safe to say if it leaks now it won’t going away…..I made special care in throughly cleaning all surfaces well….

It's a Bummer, but it's how you learn sometimes by making small mistakes. Could be as simple as the thermostat housing as these are notorious for corroding. Have a shop put a pressure tester on it and see for sure....and then do your own repair.

 

[kbfallon]

Would adding a stop leak help any….

Yes it may help....plug up your heater core or radiator.

 

[bm02tj]

Simple cartridge type carbon vs ceramic single unbalanced mechanical seals do not heal themselves. In this case, the stationary half, the ceramic element is leld in place with an elastomer that can crack. The rotary seal face is held by an O-ring and compressed to the ceramic stationary seal with a spring. Again the O-ring can fail and leak or crud in the coolant can damage the seal faces causing a leak. The most common failure is the shaft bearing going bad, causing runout at the seal faces resulting in a leak. The coolant is the actual lubricant for the seal faces. If the seal is leaking coolant from the weep hole.....don't wait.....replace the pump....it will only get worse. Just my opinion of course.
BOB RENTON

In 99.5 % of the time that is correct

 

[Steven Bowers]

After removing the pump housing again I did notice where a small trail of antifreeze came from the thermostat on the back side of the housing…..it’s possible there is a small pin hole at the top of housing…..well being the original housing it’s held up extremely well….about 53 years old now…..