Engine block core plug

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Moseley

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Hi folks, I believe I’ve got an issue with a weepy core plug, the one that is next to the distributor. Every time I’ve checked it, there is a pool of oil inside it, and as it is raised up from the block, I can’t see any way that oil could get into it, other than from below!

How are these particular ones fitted - do they bottom out in a recess and then the deformation effectively seals them, or are they just tapped in the hole until a suitable depth is reached without going too far?

Just pondering options on sorting it.

Note, in the picture I have dried the worst of the oil so that I could see the plug.

5bb8197f5bf086034b2227d83d3015b8.jpg



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gagvanman

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Are you sure the oil is coming from there? more likely to be getting past the "O" ring on the dizzy shaft and being blown back across the block, I see there is evidence of oil all round that area.
 

Moseley

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Yeh unfortunately there have been oil leaks in the past and recently in that area - both were oil cooler seals, so I certainly can’t be 100% that it is indeed weeping from that plug. The rough casting is very hard to clean! But there was a pool of oil in it, and I can’t really see how that much oil would get into it from above. The only way I’ll know is to give it some more time, but if the plug is a simple remove and repair, I might as well give it a shot whilst the engine is out.
 

67panel

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Well it is the main feed from oil pump from where they machine galleries in case.
 

atafonso

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Hi folks

I remove all of these plugs then drill and tap for allen brass plugs.
For the main reason of cleaning the oil gallery properly on rebuild as 98% of rebuilders don`t do it and leave loads of gunk, swarfs and all inside the galleries. Upon first start up, all that junk gets pushed into the oil lines scoring all the new bearings and crank.. no good :shock:

After doing the drill and tap, they become serviceable every time you strip the engine, so it`s a win win ;)

Abel
 

Moseley

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Bumping this up again as the engine is back out, and there is a lovely pool of fresh oil sat in the plug. I’m confident that this is coming from the plug itself!

Is this possible to drill and tap in situ using something inside the bore as a temporary way to catch the swarf, or is this only going to be feasible with a stripped engine and pillar drill etc? Failing that, I’m wondering if I can thoroughly degrease around the plug, and then use some liquid metal or similar to attempt to seal it. I think it will need something more hard-setting than silicone sealant as it needs to withstand the pressure of the oil behind that plug.

Or could anyone advise on where a new plug would be sourced from and how these are fitted? I’ve only ever had experience of a core plug once before, and that dropped into the hole where it bottomed out on a lip, and then it was tapped using an appropriate tool to deform it and create the seal.
 

Moseley

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I've been told that the only way to do this properly is to strip the engine and drill and tap the case for a threaded plug.
My other engine has already been done.
I’m thinking a plan B is probably the best for the time being. Which takes me back to my original question, does anyone know how these ones are fitted - do they bottom out in a recess and then the deformation effectively seals them, or are they just tapped in the hole until a suitable depth is reached without going too far?

If they sit on a step in a recess, I will try a quick tap to see if that deforms it slightly more, but I don’t want to try this if I just end up punching it too far in, or having it spin round etc!
 

naskeet

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Hi folks, I believe I’ve got an issue with a weepy core plug, the one that is next to the distributor. Every time I’ve checked it, there is a pool of oil inside it, and as it is raised up from the block, I can’t see any way that oil could get into it, other than from below!

How are these particular ones fitted - do they bottom out in a recess and then the deformation effectively seals them, or are they just tapped in the hole until a suitable depth is reached without going too far?

Just pondering options on sorting it.

Note, in the picture I have dried the worst of the oil so that I could see the plug.

5bb8197f5bf086034b2227d83d3015b8.jpg



Sent from my iPhone using Tapatalk
I don't think I have ever seen an oil-pressure switch installed so deeply in a VW Type 1 style engine's crankcase! Normally they have tapered threads which progressively become tighter and don't screw in far enough, to bottom-out the nut portion against the crankcase. Is there a sealing-washer between the nut portion and the crankcase?
 

Moseley

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I don't think I have ever seen an oil-pressure switch installed so deeply in a VW Type 1 style engine's crankcase! Normally they have tapered threads which progressively become tighter and don't screw in far enough, to bottom-out the nut portion against the crankcase. Is there a sealing-washer between the nut portion and the crankcase?
Just the angle of the photo, there’s probably another couple of turns of thread exposed. It is indeed the tapered style.
 
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