Block heater leaks, Use sealant on expansion plug?

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Colt45ws

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So, my factory installed block heater is beginning to leak. Thankfully its in the most accessible location.
Ive sourced a expansion plug from Ford (F6AZ-6026-BA) to replace it. Should I use a sealant on it when I pop it in? Ive looked about and see arguments for both ways.
 
back in HS when we rebuilt engines from scratch, we were advised to use sealant. Can't remember which one exactly, but yes, it'll still pop out if the temps are low enough to pop out the plugs (safety measure to protect the block).
 
If you're just replacing the block heater (with a new o-ring) just put it in dry. Or use a little bit of RTV or permatex aviation form a gasket. Provided the sealing surface is clean and free of corrosion, it should seal fine without anything.

FYI they're not 'freeze' plugs, even though everyone refers to them as such. They're core plugs to seal the holes that are made in the block during the casting process. Has absolutely nothing to do with frost protection. Sure, they might pop out during a frozen block event, but something else (the block) will probably crack too.

Drives me nuts when I order a core plug and the parts guy 'corrects' me by saying, oh you mean a freeze plug. SMH
 
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Originally Posted By: Canadastang
If you're just replacing the block heater (with a new o-ring) just put it in dry. Or use a little bit of RTV or permatex aviation form a gasket. Provided the sealing surface is clean and free of corrosion, it should seal fine without anything.

FYI they're not 'freeze' plugs, even though everyone refers to them as such. They're core plugs to seal the holes that are made in the block during the casting process. Has absolutely nothing to do with frost protection. Sure, they might pop out during a frozen block event, but something else (the block) will probably crack too.

Drives me nuts when I order a core plug and the parts guy 'corrects' by saying, oh you mean a freeze plug. SMH

I ordered a new core plug to install instead of the block heater. Its leaking where the cord plugs in, probably around the pins I would assume.
 
Originally Posted By: Colt45ws

I ordered a new core plug to install instead of the block heater. Its leaking where the cord plugs in, probably around the pins I would assume.


I just had the exact same leak about a month ago, replaced with a new block heater. Way easier than installing a new plug.

Do you have a seal driver to make sure the plug seats correctly? If you use the socket and hammer method, it's hit or miss as to whether it'll seal. Been there, done that.
 
Try to find a socket that will press on the outer lip of the plug. Pressing on the inside of the cup can cause it to deform while being pressed in.

My .02 - Fill the car with straight water to check for leaks first. If it leaks, you've just saved yourself from wasting a couple gallons of coolant. If it doesn't, drain the rad and refill with straight concentrate. Either way, in the end you'll have probably over 90% new coolant in the system.
 
I use brass plugs from NAPA with a little Indian Head on them.
Whats it called? Who cares we all know what it means, freeze plug, core plug, no matter.
 
Originally Posted By: Trav

Whats it called? Who cares we all know what it means, freeze plug, core plug, no matter.


LOL, normally I wouldn't care, but I've seen way too many ruined engines from folks who think "I'll run straight water all year round - if it freezes, the freeze plugs will just pop out and save my block."

And that couldn't be further from the truth.
 
Originally Posted By: Trav
I use brass plugs from NAPA with a little Indian Head on them.
Whats it called? Who cares we all know what it means, freeze plug, core plug, no matter.


Ill get the Indian head then. Thanks for the reply Trav!

Originally Posted By: Canadastang


LOL, normally I wouldn't care, but I've seen way too many ruined engines from folks who think "I'll run straight water all year round - if it freezes, the freeze plugs will just pop out and save my block."

And that couldn't be further from the truth.


I can't believe someone would actually do that. I mean, even if it saves your engine, what about the radiator and heater core? I dont see either of those fairing very well in a freeze.
 
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Oh nice! I just bought the factory one because where I looked, I could only get kits to do the whole engine or singles from Dorman. Which, while probably okay, is a bad word and not allowed on my cars anymore.
I admit, I didn't look at NAPA though.
 
Should I risk pulling the block drain? There is one right below the leaking block heater and I could pull it super easy, but Im worried about the threads coming with it. It has 190k on the engine and the coolant was never changed before I got it a few years ago. It was very nasty, which Im sure contributed to my current leak.
 
It should be okay, just soak it overnight a couple of times with penetrating oil. If after that it feels jammed then frig it and leave well enough alone.
 
So, I changed my mind and decided to put another block heater in it. Since this was my winter rig and will return to being so once I get a Marauder, I thought it would be worthwhile to have a working one.
One thing that I haven't figured out is the Temro book lists the heater element pointing at 9 o'clock, but the factory one was at 12 o'clock. I just decided to go with the book and put it at 9. Don't know why its different even though the heaters look identical.

Block drain wouldn't come out, even after 4 days of soaking it with PB.

When I was going to remove the leaking heater, I put a screwdriver on the bolt that holds it in, and it started streaming coolant. I don't know how it hadn't just started leaking driving down the road.

One thing I don't like is the heater cord is only 6 ft. Can't buy a longer one either. The 6ft is just barely long enough to put it out by the headlight. Would be nice if they sold a 10ft cord.
 
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