Bristol Cars - Owners and Enthusiasts Forum  

Go Back   Bristol Cars - Owners and Enthusiasts Forum > Bristol Forums > 8 & 10 cyl Bristol cars

8 & 10 cyl Bristol cars Type 407 onwards - restoration, repair, maintenance etc

core plugs / freeze plugs

Reply
 
Thread Tools Search this Thread Display Modes
  #1 (permalink)  
Old 01-04-10, 12:05 AM
Member
 
Join Date: Apr 2009
Location: York
Posts: 808
Default core plugs / freeze plugs

I have managed to blow a core plug on the 408. I have purchased a full set of six from BCL (£3 each ) and will put them in Friday / Saturday. As I have never done this before does anyone have any tips on how to best go about the task and the location of all six.

Thanks

Greg
Reply With Quote
  #2 (permalink)  
Old 01-04-10, 02:41 PM
Member
 
Join Date: May 2008
Location: Melbourne, Australia
Posts: 1,168
Default

Greg,

Apparently a good way to get them out is to hit the core plug to one side of centre with a punch so that it spins on it's axis in the hole. Then you can get something like mole grips on one edge and pull the core plug out.

When putting the new plugs in you need to get something like a small hard mallet or perhaps a piece of dowel or round steel bar than almost fills the back of the cup and tap it in with another mallet or hammer. If you use something too small it will push in the centre of the plug and distort it. Try to keep it square to the block and don't tap it in too far, so the edge is just below the outer surface of the block.

I have seen a metal retaining strap used which goes across the core plug and is screwed into the block on either side of the plug to stop it coming out. I can't remember where I saw this but it was probably on a high performance Chrysler V8.

Have you thought about why you lost one in the first place?
What's the pressure rating on your radiator cap?

Kevin H
Reply With Quote
  #3 (permalink)  
Old 01-04-10, 02:57 PM
Member
 
Join Date: Apr 2009
Location: York
Posts: 808
Default

Thanks Kevin,

On the plug that blew out there is a bit of corrosion and I was reving the nuts off it, showing off the sound of the V8 to a friend. I think the cap is a 15 psi - I will check that.

I only know it's had the right anti freeze whilst I have had it so I will change all the plugs just in case -- lucky it was on my driveway when it happened.

Greg
Reply With Quote
  #4 (permalink)  
Old 01-04-10, 03:00 PM
Member
 
Join Date: Apr 2009
Location: York
Posts: 808
Default

p.s. the core plugs on mine are about 4cm discs , not the cup types.
Reply With Quote
  #5 (permalink)  
Old 01-04-10, 03:30 PM
Member
 
Join Date: Jul 2008
Location: Bury St Edmunds, Suffolk, UK
Posts: 250
Default core plugs / freeze plugs

Hi Greg,

Had this happen to me, corrosion after 45 years seems to be the problem.
You have the correct pressure cap. Mine happened when I floored the beast
on the A11 out of Snetterton circuit. Very embarrassing cart home on the
back
of an AA truck.
ACCS sent me a set which are blue in colour and about 4cms across
or in old money an 1" and 5/8th also included was 1 at 1" and 7/8th stamped
with
that measurement and 1020.
I still have them sitting on my desk as I only replaced the one which came
out as
it was in the front of the engine on the nearside and easy to get at.

With only one leg, and the amount of swearing that this one took to get in,
I decided that
I had spent enough time on my back on the crawl board and if it happened
again, it would
go to a garage.

All has been well now for 3 years. Fingers crossed.
Reply With Quote
  #6 (permalink)  
Old 01-04-10, 03:56 PM
Member
 
Join Date: Apr 2009
Location: York
Posts: 808
Default

Thanks Nick,

It seems the same one on mine has popped !

My friends garage ramp is about 1/4 of a mile away, so I was going to borrow that as I don't do crawling anymore under cars on the drive.

Thats Easter sorted -- good bit of inlaw dodging :-)

Greg
Reply With Quote
  #7 (permalink)  
Old 01-04-10, 04:27 PM
Member
 
Join Date: Jul 2008
Location: Burbank, California
Posts: 135
Default core plugs / freeze plugs

One piece of advcie I've seen is to use this "opportunity" to
dig/scoop around inside the water jacket and remove any adjacent
gunk before putting the new plug back in.
Reply With Quote
  #8 (permalink)  
Old 02-04-10, 01:46 AM
Member
 
Join Date: May 2008
Location: Melbourne, Australia
Posts: 1,168
Default

Can't really see why you would need a 15 lb radiator cap. The 411s only use a 13 lb cap and the 411 engines runs much hotter than the 408 engine.

Does the 408 owners manual call for a 15 lb cap?
Reply With Quote
  #9 (permalink)  
Old 02-04-10, 08:10 AM
Member
 
Join Date: Jul 2008
Location: Bury St Edmunds, Suffolk, UK
Posts: 250
Default core plugs / freeze plugs

The reason that it has a 15lb radiator cap is that is what Bristol Cars
recommend,
It is what is in the handbook and workshop manual, it is what Brian Marelli
keeps
in stock for them.
As there is no correlation between the engines or cooling systems on the
cars I expect the workshop
manual on the 411 shows a 13lb cap on that car/engine set up.
I do not pretend to know about 411's only 407,408 engines and cars.

I would never presume to pull up the fountain of all knowledge on 411's but
I do have a workshop
manual for a 407, I would never dream of disputing you on a 411 so why
question me and a 407/8.

Nick.
Reply With Quote
  #10 (permalink)  
Old 02-04-10, 08:52 AM
Member
 
Join Date: Apr 2009
Location: York
Posts: 808
Default

This is the core plug that I found on the drive. Nothing more than corrosion over about half the plug with some galvanised plating still in tact.

No new ones in thee post yet ! Maybe I will weld the old one back in :-))

Conclusion : The damage is down to age and a plonker owner over revving the engine.

Thanks for all the help and guidance especially to Alan Blackwood for taking the time to call and go through the procedure and giving me the proper dad advise about not fixing things that are not broken !.

Greg
Attached Images
File Type: jpeg coreplug2.jpeg (15.0 KB, 22 views)
Reply With Quote
  #11 (permalink)  
Old 02-04-10, 09:44 AM
Member
 
Join Date: Apr 2009
Location: York
Posts: 808
Default

And while I have your attention - any ideas on the best antifreeze to treat her to?

Thanks

Greg
Reply With Quote
  #12 (permalink)  
Old 02-04-10, 02:30 PM
Member
 
Join Date: May 2008
Location: Melbourne, Australia
Posts: 1,168
Default

Quote:
Originally Posted by Nick Challacombe View Post
I would never dream of disputing you on a 411 so why question me and a 407/8.
Nick,

Why the rant?

I asked a simple (and very specific) question;

"Does the 408 owners manual call for a 15 lb cap? "

All you needed to say was "Yes".

Kevin
Reply With Quote
  #13 (permalink)  
Old 02-04-10, 02:59 PM
Member
 
Join Date: Jul 2008
Location: Bury St Edmunds, Suffolk, UK
Posts: 250
Default core plugs / freeze plugs

Why rise to the bait, I knew you would!!

What a laugh, you can give it but not take it!!
Reply With Quote
  #14 (permalink)  
Old 04-04-10, 01:12 PM
Member
 
Join Date: Apr 2009
Location: York
Posts: 808
Default End of core plug saga

Well it got to Saturday morning and still no core plugs in the post from BCL !

In desperation I looked on ebay to see if I could see something from another car that looked the right size - the original Mini looked close. I managed to find a Mini specialist close to where I live and took the old core plug along to compare. They are identical !

Jacked her up and put the axle stands under and 15 minutes later anti-freeze in and running - what a piece of piss !

I wish all the d.i.y. jobs went like that !

Next job is to fit my new high torque starter.

Thanks again to all

Greg
Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


All times are GMT. The time now is 01:14 AM.


This is the live site

Search Engine Friendly URLs by vBSEO 3.6.0 PL2