Problem with core plug removal

[mbs2013]

Hi everyone

Wasn’t sure whether this would be one for the engine or cooling system section as it could be argued for both, but I’ve got a hole in one of the core plugs on my Mk3 Spitfire which I’m trying to replace. The engine is in-situ and it is the larger core plug at the bulkhead end of the block. I’ve tried the self-tapping screw and screwdriver through the centre options and neither will shift it and I’ve ended up with a larger hole (it was originally about 3mm)

Aside if removing the engine for easier access, does anyone have any tips that may help? I’ve attached a photo of the plug and the hole is just under 1cm in dIameter.

Thank-you in advance

[johny]

Next step is a bigger screwdriver or possibly hub cap remover/wheel brace tool. You might have to find something to hold in place and lever on.

Or if theres enough room find a socket the right size and hammer it in slightly to get it free. Dont knock it in all the way in though as it might drop into the internal waterway...

[mbs2013]

Thanks. I’ll try the hub cap remover idea tomorrow. It’s a bit awkward to get the socket and hammer in given what is around it but I’ll try a few positions and see if that works if the first option doesn’t.

[Ian Faulds]

Can you not just chisel down to the engine block from the hole and collapse it

[johny]

Only got to be really careful not to damage sealing face of hole in block....

[Pete Lewis]

yes big screwdriver  and prise the thing maybe add a pivot/fulcrum point to get the  advantage of  full leverage  

Pete

[mbs2013]

Thank you all for the advice. It’s still not playing but I’ll give it another try tomorrow 

[ahebron]

Refitted the reconditioned head to my Dads Vitesse 2 litre Convertible.
Bolted all the ancillaries up.
Filled the cooling system and heard then saw water at the back of the head.
Head reconditioner had forgotten to refit the rear welsh plug.
Took the head off to get it fitted.

My dad still mentions that some 20+ years later.

 

Adrian

[Mathew]

Is it me or is it the most hard to get too one goes! My first spitfire it was the rear head one!

[68vitesse]

Would one of the seal removers work, if you've got one.

Regards

Paul.

 

 

 

[RogerH]

1 hour ago, ahebron said:

Refitted the reconditioned head to my Dads Vitesse 2 litre Convertible.
Bolted all the ancillaries up.
Filled the cooling system and heard then saw water at the back of the head.
Head reconditioner had forgotten to refit the rear welsh plug.
Took the head off to get it fitted.

My dad still mentions that some 20+ years later.

 

Adrian

I rebuilt a TR4 engine about 6 years ago. Had the block  worked on and acid cleaned. All looked very good.

A week after initial  start up ( and on a long run)  oil p*ss*d out the front and back. the rebuilder had removed the oil gallery plugs and then refitted them loosely.

I can understand why they did it but they never told me and so the were never tightened.

I had to removed the engine, strip the front and back and finish the job with new plugs.  That will NEVER happen again 

 

Roger

[mbs2013]

So I've tried a pry bar and chisel and all I've got is a bigger hole but the outer ring still won't budge. I can feel the block behind it so I'm a bit warey of sticking anything further behind the plug to remove it. I'm reluctant to have to take the head off at this time but it is starting to look like the only option. I did want to carefully try a mini hacksaw but it is too long to get it in and maneuvered.

[RogerH]

Take the head off and do it properly.

It will give satisfaction that that it is out of the way.

 

Roger

[Mathew]

1 minute ago, RogerH said:

Take the head off and do it properly.

It will give satisfaction that that it is out of the way.

 

Roger

Some times it is quicker to do ! By the time you have it out and the new in and then your be wondering if it is ok! 

[johny]

Im really surprised it wont shift. Youve scraped away the rust round the outer ring as much as possible? And youve tried knocking it in slightly with a long bar?

Sawing will be difficult with the poor access and risk of damaging the block sealing face. You know if you take the head off the plug will fall out😜

[mbs2013]

Yeah I've scraped the rust away. There is barely a centre left to the plug now given that fell apart but the outer rim is still in place. I'll have another try with it tomorrow and hopefully it will move. Would heating what remains make any difference?

[Pete Lewis]

not really  just brut force  not easy as access has the body in the way 

can you get a sharp chisel to cut the ring dont go mad and chop the block but the ring is much softer stuff than the block/head casting  

you can be quite rough and aggressive  withoout doing much harm 

uon refit use something like loctite 574 wich sets when air is excluded   not any silicon slippy stuff or the plug may slide out under pressure

as a rule always fit them dry but 574 or similar is bullet proof stuff

Pete 

 

[Badwolf]

You could try heating with one of those pencil gas torch thingies, around the edge of the plug and then try to pry out the rim. Thinking that the very localised heat may soften the rim of the plug enough to be able to bend it without damaging the block. Just a thought over lunch.

[68vitesse]

1 hour ago, RogerH said:

Take the head off and do it properly.

It will give satisfaction that that it is out of the way.

 

Roger

If you do change all of them.

Regards

Paul

[Paul H]

I accessed the front plug after removing the gearbox cover in my Vitesse . I was replacing the slave cylinder when I noticed the plug was leaking . If you chisel with an old screwdriver from the middle to the side then chisel like a can opener the plug will eventually buckle enabling it to be prised out 

Paul 

[Badwolf]

I have been thinking too much about this!!  Here is a really ridiculous idea but it may lead on to something more practical. Enlarge the core plug hole as much as you dare. Out of tin foil or similar form a hollow plug that will go in the hole.. make it as long as possible. Fill the hollow plug that you have formed, with water and freeze to -20 overnight. The next day, heat up the remains of the plug and surrounding block. When hot, insert the ice plug for a few seconds.. then try to get the remains of the plug out. The difference in temperature may just break the seal.  Fanciful idea but its been a nice day and I have been thinking about it while doing the gardening. Good luck. Off to the BBQ now.

[mbs2013]

Thanks for the suggestions. I'll let you know it goes

[Bfg]

I use a 1/2" wood chisel to prise / lever them out, its flatness helps.  

Being that stubborn ; I would run around the plug's perimeter with a small flat ended punch to see if such localised hammering would crack its hold, and perhaps knock the core plug in cocque hat / twisted. 

I have on occasion had to resort to using my small sharp steel chisel (its head is only about 3 or 4mm wide) between the protruding rim of the plug and the inside of its hole ..to peel it away from the side. Some have been put in with Araldite, but as your core plug shows a clean rim I'd guess its just a darn good fit or has been assembled with Loctite.   

Sounds as if your access is awkward - but not impossible.  I'm not sure that removing the cylinder head would help that much.  Personally I wouldn't want to open up other potential issues that always seem to add many-fold to the task when things are disturbed.

Pete   

[thescrapman]

Judging by state of bell housing studs and nuts it looks like that car has sat for many years in damp environment, field or under a tarpaulin.

The other core plugs will not be far behind the one you are trying to fix.

 

[Pete Lewis]

if the hole is big enough to get behind the rim then all you need is something that will grasp/ lock into the rim and have a looooong  handle to exert 

real pressure  to lever the sod out , its no use tickling it , you need to show it who's boss

Pete