Engine/Transmission (1998.5 - 2002) Coolant leak at heater core supply hose

[RDMueller]

I’ve noticed a slight coolant leak at the heater core supply hose. Initially I thought it was leaking between the barb that is threaded into the block and the hose itself, so I replaced the hose. No help. Tried a different hose clamp, still no help. After closer inspection it appears the leak is actually between the barb fitting and the block itself. My question is whether there is a special type of sealant needed for this application as opposed to using teflon tape or plumbers pipe dope. Thanks!

 

[SAndreasen]

I’ve noticed a slight coolant leak at the heater core supply hose. Initially I thought it was leaking between the barb that is threaded into the block and the hose itself, so I replaced the hose. No help. Tried a different hose clamp, still no help. After closer inspection it appears the leak is actually between the barb fitting and the block itself. My question is whether there is a special type of sealant needed for this application as opposed to using teflon tape or plumbers pipe dope. Thanks!

high tack or aviation sealant or pipe thread sealant

 

[RDMueller]

Thank you!

 

[Cummins12V98]

Personally I like Teflon pipe dope.

 

[bcbender]

I've always had good luck on threaded pipe joints with the PTFE liquid pipe sealant.. use it all the time, coolants, oils, fill/drain plugs..

 

[Cummins12V98]

I've always had good luck on threaded pipe joints with the PTFE liquid pipe sealant.. use it all the time, coolants, oils, fill/drain plugs..

View attachment 139712

The one I typically use is the same pictured but in blue print. Teflon tape is great if you can find the QUALITY but most is junk. Have not looked back using the Permatex Teflon.

 

[RDMueller]

Appreciate the suggestions. Probably can’t go wrong with the Permatex and I can pick it up at the auto parts store. Thanks again!

 

[Matt42]

For PTFE tape applications, I use Blue Monster. I've given up on everything else. Permatex No. 2 should work on the cooling system application being discussed, though.