9 replies to this topic

[babsbrown]

Hi guys,

Really embarrassing story to tell, but I don't want anyone making the same mistake


Basically I rebuild an A series engine with the domed freeze/core water plugs. I tapped them in with a drift denting the middle and the seemed to hold fine. I had also added ATV silicoln sealant to the lip


Getting my engine running at 2500rpm with the engine at full temperature, a core plug shot out sending a blast of high pressure scalding coolant all over my bare legs.

Thought I'd be OK, but
Ended up having quite badly blistered legs and needed a fair bit of medical attention.

Having inspected the core plug. It seems I have dented the outside but this hadn't actually made enough of a deformation to secure the plug fully.

So please, give yours a good solid wack home. And make sure those buggers are in tight.

First time doing this for me and I've learnt the hard way.

I just feel so so lucky neither of my kids were standing in front of the car. Doesn't bare thinking about.

Cheers, Luke

[Spider]

I hope you pull up OK for this injury.

 

They do need a few carefully placed hits, belting them actually doesn't expand them, they need to be almost flat.

 

I clean the recesses in the block very carefully and check them for scores etc, otherwise while they may go in tight, they'll leak.

I also use Loctite 243 (yes, it's a thread locker) on them before fitting as 'insurance' that they won't leak or dislodge.

[timmy850]

Mine was OK for 4 years and then popped out in a national park where there was no phone reception. Luckily I had a few mini friends with me or I'd have been in for a longer day

 

[absx2]

Thanks for sharing

[Shooter63]

I'm glad you are sort of OK, when I put new core plugs in a recent small bore build I deliberately sort out some brass core plugs from an online company as I presumed they would be softer, as others have said I used a wire brush in a drill to make sure there was good clean fresh metal, I used Hylomar core plug sealant, I used a large ball peen hammer as a dolly hit with another hammer to make the dent, then a socket to flatten out the outer edge.

Shooter

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[babsbrown]

I hope you pull up OK for this injury.

They do need a few carefully placed hits, belting them actually doesn't expand them, they need to be almost flat.

I clean the recesses in the block very carefully and check them for scores etc, otherwise while they may go in tight, they'll leak.

I also use Loctite 243 (yes, it's a thread locker) on them before fitting as 'insurance' that they won't leak or dislodge.

Thanks Spider,

Could've been a lot worse and definitely a learning point. I'll have to have a look at that loctite, I was tempted to get some for my 3rd motion shaft bearing but never did. Could've killed 2 birds with one stone there.

[babsbrown]

Mine was OK for 4 years and then popped out in a national park where there was no phone reception. Luckily I had a few mini friends with me or I'd have been in for a longer day

Wow that's some heat isn't it!! How was the head gasket after that? Did anything warp?

[babsbrown]

I'm glad you are sort of OK, when I put new core plugs in a recent small bore build I deliberately sort out some brass core plugs from an online company as I presumed they would be softer, as others have said I used a wire brush in a drill to make sure there was good clean fresh metal, I used Hylomar core plug sealant, I used a large ball peen hammer as a dolly hit with another hammer to make the dent, then a socket to flatten out the outer edge.

Shooter

Thanks shooter

I'll invest in a better ball peen I think. That's a great idea, thanks for the tip. If only I'd have seen this picture first haha. Mine didn't look anywhere near like that.

[Avtovaz]

i had the same thing on my volvo engine, and it was built by a so called professional! I used chemical metal on them. Been ok for 2 years now. Hylomar is probably the better one.

[stuart bowes]

ouch! hope you heal up quick mate