MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - Fitting Core Plugs

Hi,

Anybody out there have any recommendation for fitting core plugs to an XPAG engine, dry or with a sealant, if so what sealant.

Bernie
B W Wood

Hi Bernie,
I have (over 50 years) never had a failure using Araldite (epoxy glue) and brass plugs. I am sure other readers will suggest other sealants which also work well. "Panel Beat" them until they are just short of flat. I suggest you do not put them in dry!
Bob Schapel

R L Schapel

Hi Bernie,

I recommend using Three Bond Welch Plug Lock Fix and Seal. A brilliant sealant specifically made for core plugs. Available from Bursons Auto Suppliers in Australia.

It is very important to thoroughly clean out any debris from the block's core plug hole areas before fitting new core plugs. I used Tom Lange's brass core plugs. They are a better fit and quality compared to any other
suppliers. Note that the core plugs should be in metric and not imperial sizing.

I used these products recently on the TF1500s motor rebuild. Not a drop of coolant leaking out anywhere.

Cheers
Rob Grantham
TF3719("Aramis"),TF9177("Athos").
Rob Grantham

I used “Stag” jointing compound (claimed to be suitable for steam) with a set of brass plugs. 5 of them leaked! Admittedly a couple of the seats were in poor condition but certainly not all 5. I replaced them using J.B. Weld with a liberal fillet on the outside - so far so good.
Chris
C I Twidle

Having had problems the first time round, I used JB Weld and they are now leak tight.
Dave H
Dave Hill

May as well have a say,
I get it all squeaky clean, brass plugs and wipe a coat of my favourite -Loctite 577 pipe sealant around in the hole, -poke the plug in and flatten it to just short of flat, as Bob has already mentioned,
Don't know how many plugs I've seen that have just been dented in the centre, some having been dented that far in over a small area that they couldn't possibly be a good tight fit--The aim should be to get them "almost" flat, but not quite--
William Revit

I am sure that you are right. I've had no problems on other engines when just denting them in the middle, but the XPAG seems to need a bit more.
Dave H
Dave Hill

For what it's worth, the plug were not supposed to be dimple in the middle. There are supposed to be concave punches that are almost the same diameter of the plug that compress the center, expanding them out, with no visible depression.

Hubbard Spring produced them starting in 1913 and had installation instructions on their website, but have removed them. hubbardspring.com Check out the site and where is says CONTACT US, petition them to reinstall those pages.

I'm going to post a series of photos on how I made up my tools.

1st pic facing off bar in lathe


JIM N

pic 2 using cutoff wheel to dish it slightly

JIM N

pic 3 smoothing with flapper wheel



JIM N

pic 4 almost finished tool

afterwards, I polished it on buffing wheel more for looks

also put clear tape over the end for soft surface

JIM N

pic 5 shows clearance at the outer edge

Hubbard's installation instructions offered dimensions

ask them for the dimensions and installation pages

JIM N

pic 6 set of 3 tools for XPAG

The lengths & shapes were determined by the scrap pieces of chrome bar available. Dealing with hydraulics, I've accumulated lots of chrome plated scrap bars but any steel bar should do.

I made up a set for Tom Lange, so you might get his opinion on this subject.

JIM N

pic 7 as installed

The objective is not to just stake the center of the plug, but to drive the outer edge to the back of the hole and flatten it ensuring expansion and sealing around the perimeter.

Before you install your plugs consider cleaning out the ports behind the channel. Those are the two bottlenecks in the cooling system. more pics coming

JIM N

pic 8 one of the ports "as cast"

sorry about the focus, or lack of focus!

JIM N

pic 9 air die grinder with long stone "weapon of mess destruction"

JIM N

pic 10 slightly larger, clearer port

JIM N

Nice work Jim with very good explanation.

On JB Weld as a core plug seal, it no doubt works well. However I have heard
that it can be a 'bear' to clean this sealant off the engine block's core plug hole edge if they are ever replaced !

Cheers
Rob Grantham
Rob Grantham

It can be removed with a rotating wire brush in a drill, etc.
Dave H
Dave Hill

I don't think JB Weld existed when I started using "Araldite". JB Weld is actually a more modern version of Araldite epoxy glue and is impregnated with fine metal powder. I have used it to seal water jacket plugs when "dry-decking" engines. Great stuff! Sounds like the modern version of what I have done.
Bob
R L Schapel

I second JB weld. Likely the block holes are rough and irregular due to rust, age, etc. Most important to use correct plugs such as Tom Lange's brass ones. The large rear and center under manifold steel plugs sold by the major suppliers for a long time were paper thin and fractionally too small. Big problem when the rear one pops out. George
George Butz III

A few of you mention JB Weld, but which one there is so many.
B W Wood

Just the regular J-B Weld twin tube product that is sold everywhere, and not Kwikweld, Woodweld, epoxy putty or any other variant.
Dave H
Dave Hill

Has anyone devised a way of recutting the recess in the block? I would feel much happier fitting a core plug to a nice, regular, smooth seating irrespective of what sealant I was using.

Jan T
J Targosz

I used the JB Weld. As Jan noted the issue in my case was the recess. Just to much damage from rust for it to seal without help.

The key to me is a complete smooth ring to completely seal the disk and block. See picture.

Joe

JWP Policastro

This thread was discussed between 12/12/2018 and 20/12/2018

MG TD TF 1500 index

This thread is from the archives. Join the live MG TD TF 1500 BBS now