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99 Head Gasket Blowing By

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Re: 99 Head Gasket Blowing By

Posted by Charles Bovington at March 14. 2017

Previously anna jeannette Dixon wrote:

Previously Jonathan Soons wrote:

Previously anna jeannette Dixon wrote:

Hello And fitting a composite Gasket may still blow, the first thing you need to know for sure is the Cylinder head  true  and flat   to do this you have to Remove all Studs for a Start,   and Removing Spigot is a very BAD idea   Norton had these in place for a reason  They only removed them has the Bore got so big they could not be accommodated anymore  you find out the hard way there is not many short cuts in engineering

yours  anna j

He told us the head is dead flat but the copper gasket still leaks.  He may have better luck with a spongier gasket and Wellseal to fill the gap rather than flat surfaces.

Hello Jonathan  you alway check things yourself  never trust anyone else  unless you know them well enough  anyone can say   the head is true and flat  if this was the case  then there should be No gaps anywhere     Yours   Anna J 


You are in danger of becoming a pain in the neck, or some other part of the anatomy, over this. So for some part of the last 45 years you were in marine engineering in some capacity. Many members are highly qualified as professional engineers or as engineering technicians. They seem to have been blessed with a modesty that you lack and a ability to know what it is that they know and what it is that they don't know..

Re: 99 Head Gasket Blowing By

Posted by ian_cordes at March 15. 2017

Previously Jonathan Soons wrote:

 

Ian, What prompted you to remove the spigots from your 650?  Were they breaking up?

 

Correct Jonathan. Mine are + 0.040" and the spigots had cracked. It was a case of a re-sleeve or have the spigots removed. I am not really happy with it, and suspect I will bite the bullet and have it re-sleeved to standard; with spigots! Removing them is the last resort imo, although others have been successful with it. That is why I said it is bad advice to suggest removing perfectly good spigots. With no spigots and a head for a spigotted barrel, I believe it leaves insufficient mating surfaces to guarantee a good seal.

Re: 99 Head Gasket Blowing By

Posted by anna jeannette Dixon at March 16. 2017
Previously Charles Bovington wrote:

Previously anna jeannette Dixon wrote:

Previously Jonathan Soons wrote:

Previously anna jeannette Dixon wrote:

Hello And fitting a composite Gasket may still blow, the first thing you need to know for sure is the Cylinder head  true  and flat   to do this you have to Remove all Studs for a Start,   and Removing Spigot is a very BAD idea   Norton had these in place for a reason  They only removed them has the Bore got so big they could not be accommodated anymore  you find out the hard way there is not many short cuts in engineering

yours  anna j

He told us the head is dead flat but the copper gasket still leaks.  He may have better luck with a spongier gasket and Wellseal to fill the gap rather than flat surfaces.

Hello Jonathan  you alway check things yourself  never trust anyone else  unless you know them well enough  anyone can say   the head is true and flat  if this was the case  then there should be No gaps anywhere     Yours   Anna J 


You are in danger of becoming a pain in the neck, or some other part of the anatomy, over this. So for some part of the last 45 years you were in marine engineering in some capacity. Many members are highly qualified as professional engineers or as engineering technicians. They seem to have been blessed with a modesty that you lack and a ability to know what it is that they know and what it is that they don't know..

   Well what you do not know is what I know and do not know  is the question   And Know Norton twins cylinder heads like the back of my hand   I sorted out many of them over the years       now have fun in the sun    yours  anna j   

Re: 99 Head Gasket Blowing By

Posted by anna jeannette Dixon at March 16. 2017
Previously ian_cordes wrote:

Previously Jonathan Soons wrote:

 

Ian, What prompted you to remove the spigots from your 650?  Were they breaking up?

 

Correct Jonathan. Mine are + 0.040" and the spigots had cracked. It was a case of a re-sleeve or have the spigots removed. I am not really happy with it, and suspect I will bite the bullet and have it re-sleeved to standard; with spigots! Removing them is the last resort imo, although others have been successful with it. That is why I said it is bad advice to suggest removing perfectly good spigots. With no spigots and a head for a spigotted barrel, I believe it leaves insufficient mating surfaces to guarantee a good seal.

 

   Hello Norton 650 barrels were only made to go to plus 30 oversize  that why the spigots get thin  and break                   yours  anna j    

Re: 99 Head Gasket Blowing By

Posted by ian_cordes at March 16. 2017

Unfortunately aftermarket manufacturers are happy to make + 0.040" pistons readily available, and they don't come with a warning on the packet! In fact, Andover Norton, RGM and Norvil all offer +0.060" pistons.....  I agree, +0.030" is big enough for the 600/650's, although no-one appears to offer pistons in that size.

Caveat emptor......

Re: 99 Head Gasket Blowing By

Posted by anna jeannette Dixon at March 16. 2017
Previously ian_cordes wrote:

Unfortunately aftermarket manufacturers are happy to make + 0.040" pistons readily available, and they don't come with a warning on the packet! In fact, Andover Norton, RGM and Norvil all offer +0.060" pistons.....  I agree, +0.030" is big enough for the 600/650's, although no-one appears to offer pistons in that size.

Caveat emptor......

Hello  and what their offing are  Giardini pistons there must be a mountain of them,And there on the heavy side,  JP pistons  are the better ones,  But  All The BHB Original piston went to the USA So there out there hidden someone's ones lock up  or garage  I found a set of New Old stock Orginal pistons + plus 10 BHB pistons with rings and I have seen too plus 30 oversize to with rings  so is a matter of searching the internet 
  yours   Anna j 

Re: 99 Head Gasket Blowing By

Posted by Lance Crossley at March 17. 2017

Hello  and what their offing are  Giardini pistons there must be a mountain of them,And there on the heavy side,  JP pistons  are the better ones,  But  All The BHB Original piston went to the USA So there out there hidden someone's ones lock up  or garage  I found a set of New Old stock Orginal pistons + plus 10 BHB pistons with rings and I have seen too plus 30 oversize to with rings  so is a matter of searching the internet

yours   Anna j

My recent experience has been just the opposite! Having recently had my 650SS re-sleeved back to standard bore my service provider used JP pistons and they were approx 70 grams each heavier than the old, +60 pistons and couldn't be lightened sufficiently. I have now replaced them with Gandini pistons which are lighter than the old ones, so well lighter than the JPs. Additionally I had oil burning problems with the JPs and whilst these were diminishing with mileage the Gandinis have been fine from day one.

Re: 99 Head Gasket Blowing By

Posted by ian_cordes at March 17. 2017

Funny you should say that Lance. My + 0.040"'s are BHB, and the borer said they were cr#p, with one slightly larger than the other, which meant he had to bore the cylinders different sizes. As a result the ring gap is really too large, so, despite 2500 miles since, including a change of rings to include the 3-piece oil control rings, it still burns oil.

What with that, the spigots cracking and Norvil having supplied me with a camshaft of I know not what specification, which has proved impossible to accurately time, I am despairing with this engine.

Re: 99 Head Gasket Blowing By

Posted by anna jeannette Dixon at March 18. 2017
Previously Gordon Johnston wrote:

Anna, you mention 45 years marine engineer.

Can you confirm your education and engineering experience perhaps?

Selby Technical College, City and Guilds Motor Technician.

3rd Engineer ships March 1974 - October 1979.

Security Guard September 1999 to present.

Or is your LINKEDIN profile in error perchance?

Hello I do engineering for a small firm just down the road from me they do reconditioning of marine diesel's   like Perkins and Garnder and Lister/ Petters Dorman/ Ruston /Blackstone's / Kelvin  Paxman Riccardo and ENGLISH ELECTRIC   along with other like Allen Diesels  Newbury.  National   Detroit and  Glenniffer Barrus   Mercruiser  Sabb  and the like   i do small parts and cleaning and fitting engines, and Security work part time at nights   but now only do bits a bobs  I getting to old  for it now,   anyway  do enjoy your Nortons   
 

Re: 99 Head Gasket Blowing By

Posted by anna jeannette Dixon at March 18. 2017
Previously ian_cordes wrote:

Funny you should say that Lance. My + 0.040"'s are BHB, and the borer said they were cr#p, with one slightly larger than the other, which meant he had to bore the cylinders different sizes. As a result the ring gap is really too large, so, despite 2500 miles since, including a change of rings to include the 3-piece oil control rings, it still burns oil.

What with that, the spigots cracking and Norvil having supplied me with a camshaft of I know not what specification, which has proved impossible to accurately time, I am despairing with this engine.

Hello  well let's go back in history  Rolls Royce  demanded  good quality pistons  and  B-H-B came up with the goods and have been making them since the mid-1920s  and most car and motorcycle manufacturers  used them  right into the late 1960s  and then became Apart of Auto engineering   and  JP pistons Australia  and Giardini Pistons Itlay  were under license to make copies of the Original  pistons  to BHB design or AE Auto parts  by then  And is very odd you had a some what odd pair of pistons this does not mean there Crap     yours   Anna j

Re: 99 Head Gasket Blowing By

Posted by anna jeannette Dixon at March 18. 2017

Hello And this is All off topic  and going no where   Yours  Anna J  

 

Re: 99 Head Gasket Blowing By

Posted by richard_hudson1 at April 11. 2017

Previously robert_tuck wrote:

Bearing in mind the Victorian factory these machines were built in I would not have expected a greater degree of accuracy in machining, what you have measured is probably typical. A bit of "blueprinting" would not hurt.

 

I agree entirely, the machine was probably pre war and still machining barrels until the non spigot variety appeared. 0.0015" seems quite accurate for machining around the spigots. Good luck with the scraping, I made my own surface plate as an apprentice in 1960, the hard bit towards the end was trying to remove it from the inspection plate when it would wring itself on, it is still going strong.

 

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