Core plug removal method

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zigzagsky
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#1 Core plug removal method

Post by zigzagsky » Sat Sep 09, 2017 3:07 pm

Noticed a small patch of coolant under the car today and have traced it to one of the engine core plugs leaking. It's the plug near the distributor on the right hand side of the engine (lower one of the two in that location).

It looks like it's leaking from a small pinhole in the plug itself and has happened before as there seems to be signs of JB Weld or similar being used in the past.

I think I can get to it once I remove the air-box etc.

Any removal and replacement tips guys?
Brian
1969 Primrose yellow Series 2, 2plus2
Boyhood dream fulfilled at last!

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christopher storey
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#2 Re: Core plug removal method

Post by christopher storey » Sat Sep 09, 2017 5:16 pm

I take it that this is a cup type plug rather than the earlier dished type which had to be hit in the centre to secure them . The easiest removal method is to jab a sharp screwdriver through the weakest point of the plug, and widen the hole out until it is big enough to admit a lever of some sort. I use one of the screwdriver/rightangle levers that used to come with toolkits to lever hub caps off . Put the short right angle through , and you then can use it against the cylinder wall to lever the plug out. As for replacement, you can put them in "dry", but I clean up the aperture and the lands against which the plug abuts, and then smear araldite round the land and drive the plug in with a block of wood

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#3 Re: Core plug removal method

Post by Hugo » Sat Sep 09, 2017 8:46 pm

If you've got one leaking, the others probably won't be far behind (and there are a lot of them!). I took all mine out by something like the above method & have stainless ones ready to go in when I get the block back from Formhalls where it's being rebored.
As for fitting the new ones, or rather sealing them, I have been using POR 15 lately on a variety of projects, and remarkable stuff it is. They sell it in a box of six or eight very small tins as well as the larger sizes, and with good reason. The first tin I used, by the time I had dipped into it a few times for sundry small items, the lid was so firmly stuck on it was quite impossible to get off! Levering it just bent the lip up. Having mangled the lip all the way round, the only way in was to drill a hole in the lid & then seal it with masking tape! I've never known anything stick like it. Might be good stuff to stick core plugs in?
Hugo Miller - rebuilding an imported Series II OTS & converting to RHD

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#4 Re: Core plug removal method

Post by abowie » Sat Sep 09, 2017 9:57 pm

I drill them and use a slide hammer with a threaded screw end. This is a lot easier and quicker than using a chisel.
Andrew.
881824, 1E21538. 889457..oops. Jezza the V12 XJS race car.
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#5 Re: Core plug removal method

Post by zigzagsky » Sat Sep 09, 2017 9:58 pm

Thanks for the tips guys.

Yes mine are the later type and will order up a few as you're right, others may follow shortly.

Tip on using Por15 is interesting, had an email from Frosts to say it's back in stock so will order some up.
Brian
1969 Primrose yellow Series 2, 2plus2
Boyhood dream fulfilled at last!

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Series1 Stu
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#6 Re: Core plug removal method

Post by Series1 Stu » Sat Sep 09, 2017 10:10 pm

I had this to do on my 420 and found it to be one of the easier jobs, after I'd stripped off the carburettors etc.

As Christopher said, remove it using a sharp chisel or old screwdriver and clean up the mating faces to get rid of any crud etc. Flush the block, if necessary.

I would fit the new core plug dry and without any form of adhesive unless the sealing face on the block is severely pitted. Drive it in squarely and you will hear the tone of the drifting in change when the plug hits the seat. Then tap around the edges of the plug to ensure its seated all around.

Regards
Stuart

If you can't make it work, make it complicated!

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#7 Re: Core plug removal method

Post by abowie » Sun Sep 10, 2017 4:15 am

Series1 Stu wrote:
I would fit the new core plug dry and without any form of adhesive unless the sealing face on the block is severely pitted.
Regards
We always seal them using an epoxy core plug sealant. Nothing to lose, everything to gain.
Andrew.
881824, 1E21538. 889457..oops. Jezza the V12 XJS race car.
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#8 Re: Core plug removal method

Post by zigzagsky » Sun Sep 10, 2017 10:08 am

Aha... so there is a special core plug sealant available... excellent.

Had a look around - is this stuff made by Wurth the stuff or something different?

https://eshop.wurth.co.uk/Engine-sealin ... en/GB/GBP/
Brian
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#9 Re: Core plug removal method

Post by christopher storey » Sun Sep 10, 2017 2:58 pm

No, the Wurth product is silicone sealant. Andrew's stuff is epoxy, so Araldite is effectively the same stuff

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#10 Re: Core plug removal method

Post by rfs1957 » Wed Jun 27, 2018 9:34 am

Rather than start a separate thread, maybe I can develop this one.

Pulling stuff together now that I have my acid-dipped/machined/bored/skimmed/ground/refurbished engine components back, and am wondering about core-plug procedures.

The machine-shop have removed the 7 off 1-3/4"main ones (C.315) but not the smaller C.317 located below the rear carburettor, top LHS of the block

Image

see picture.

Can someone confirm that this is similar as regards function, removal, and re-fitting as the big ones ?

To complete the info supplied by others above, it indeed appears that the firm mentioned list a stainless alternative 1-3/4" here,

http://www.coreplugs.co.uk/index.php?ro ... uct_id=241

which whilst being marginally harder to fit, and potentially harder to get to seal, in view of its lower malleability, ought to be nevertheless appropriate if flattened with a properly dimensioned alloy slug ?

Has anyone else trodden this path please ?
Rory
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#11 Re: Core plug removal method

Post by 1954Etype » Wed Jun 27, 2018 10:19 am

Rory, there is an alternative to this type of plug. You can buy one with a thread and strap that tightens down by doing up the nut. This way, if you do get a leak, you can (in theory) simply tighten it. I have never used them but I am sure I have seen them on the XKE Lovers forums.
Angus 65 OTS 1E11497. 67 FHC 1E33656

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#12 Re: Core plug removal method

Post by rfs1957 » Wed Jun 27, 2018 10:32 am

Hi Angus,

Have answered my own question, indeed it's just another bog-standard 1" welch-plug and it should have been removed when the block was acid-dipped ............

Intruiged by the "strap" method - I thought this was to stop them falling out, hence the Guy Broad kit

http://www.guybroad.co.uk/lastest_xk_se ... stons.html

visible here ?

As the welch-plug system has functioned for 60 years I think I'll stick with the hammer, albeit with some sealant in the groove.
Rory
3.8 OTS Cream 877393 Built May 28th 1962
1978 Mini Van
(plus bevel and belt single-cylinder Ducatis)

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#13 Re: Core plug removal method

Post by dal2.0litrefrogeye » Wed Jun 27, 2018 11:24 am

Just a thought while it's drained down refill with distilled water and obviously appropriate coolant mix . Distilled water does seem to keep water ways cleaner / clearer
Its a way of life not a hobby
Darren . 64 4.2 modded 69 4.2

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#14 Re: Core plug removal method

Post by 1954Etype » Wed Jun 27, 2018 1:15 pm

That's the one Rory! I was never comfortable whacking the dished ones in - much prefer the 4.2 type.
Angus 65 OTS 1E11497. 67 FHC 1E33656

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#15 Re: Core plug removal method

Post by Hugo » Wed Jun 27, 2018 2:38 pm

I used stainless plugs on my 4.2. Stuck them in with POR-15. That stuff will stick anything to anything.
Hugo Miller - rebuilding an imported Series II OTS & converting to RHD

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#16 Re: Core plug removal method

Post by JerryL770 » Wed Jun 27, 2018 4:10 pm

I think the reason the small plug was not removed is because it is on the oil gallery, not water, so is not subject to corrosion. Therefore safe to leave in place if it did not leak before ....... before what? I might ask myself :roll:
Jerome Lunt
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