re enamelling exhaust manifolds

Technical advice Q&A
User avatar

Simon P
Posts: 1228
Joined: Thu Oct 14, 2010 4:29 pm
Location: London
Great Britain

#21

Post by Simon P » Thu Sep 05, 2013 8:55 am

Heuer wrote:the front one has all the enamel cracked simply because it got wet when rain rushed down the bonnet vents when braking.
It's for that very reason that Jaguar elected to fit the E-type with 'non-retardant' brakes in the first place....

:D

Link:
BBcode:
HTML:
Hide post links
Show post links


daykrolik
Posts: 63
Joined: Fri Feb 25, 2011 11:33 pm
Location: New York City
United States of America

#22

Post by daykrolik » Thu Sep 05, 2013 12:44 pm

I did follow the SNG break-in heat cycling instructions. I was afraid of the answer that rain may still be their nemesis. I put a new set of manifolds on my XK 150 around 1985 and this year they are still perfect. It's truly a shame that we can't get reliable vitreous enamel anymore; the cars look so much better and as they left the factory. I just can't get used to otherwise lovely XK motors with tatty manifolds. Oh well.

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Heuer
Administrator
Posts: 14744
Joined: Sat Mar 01, 2008 5:29 pm
Location: Nottinghamshire
Great Britain

#23

Post by Heuer » Thu Sep 05, 2013 12:53 pm

SNGB use the same vitreous enamel process as Jaguar did and they share the same weakness - water. In period it was rare for the manifolds to last more than a year (especially in Europe because of the climate) and Jaguar used to replace them under warranty according to someone I was talking to who worked for a dealership at the time. The cracked enamel parts were sent back for cleaning and refinishing and went back on the spares shelf awaiting the next warranty claim. As soon as the car was out of warranty it was no longer an issue and of course many owners did not bother or care about the manifolds as it did not affect performance.
David Jones
S1 OTS OSB; S1 FHC ODB
1997 Porsche 911 Guards Red

Add your E-Type to our World Map: http://forum.etypeuk.com/viewtopic.php?f=1&t=1810

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

TrevS
Posts: 170
Joined: Mon Oct 06, 2014 12:24 pm
Great Britain

#24

Post by TrevS » Fri May 22, 2015 4:34 pm

Sorry to revive this topic but interested to know what the best coating people have used. Had initially looked at Zirotec but it seems an expensive route for something that might not last.

Would I be better off buying some stove/bbq paint as a cheap and fairly easy way to improve the manifolds? If so does anyone have a recommendation

Thanks

Trev
- Trev S -

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

mgcjag
Moderator
Posts: 8070
Joined: Fri Jul 09, 2010 6:15 pm
Location: Ludlow Shropshire
Great Britain

#25

Post by mgcjag » Fri May 22, 2015 5:09 pm

Hi All...A friend has just used Cerakote on his E....only done 200 miles so far but lookes good....he used this Co but there are others that Cerakote http://www.tacticalcoatings.co.uk http://www.cerakotehightemp.com Steve
Steve
69 S2 2+2 (just sold) ..Realm C type replica, 1960 xk150fhc

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

abowie
Posts: 3879
Joined: Wed Sep 07, 2011 9:15 pm
Location: Australia
Contact:
Australia

#26

Post by abowie » Fri May 22, 2015 8:44 pm

TrevS wrote:
Would I be better off buying some stove/bbq paint as a cheap and fairly easy way to improve the manifolds?
Trev
That's what I use. Well HT black exhaust spray paint..

Clean with grinder and flap disc to this:

Image

and paint for this:

Image

We've just fitted a set of ceramic coated manifolds from XK's for a customer's car. At $US399 each not cheap. They look sort of semi gloss and are not a lovely smooth finish like the original enamel. Will let you know how they fare.
Andrew.
881824, 1E21538. 889457. 1961 4.3l Mk2. 1975 XJS. 1962 MGB
http://www.projectetype.com/index.php/the-blog.html
Adelaide, Australia

Link:
BBcode:
HTML:
Hide post links
Show post links


daykrolik
Posts: 63
Joined: Fri Feb 25, 2011 11:33 pm
Location: New York City
United States of America

#27

Post by daykrolik » Fri May 29, 2015 1:11 am

Come on folks, this is simply ridiculous. I refuse to accept that in 2015 (the post space age) SOMEONE cannot offer a reasonably durable semi gloss black manifold coating which replicates and improves on that which Jaguar used over half a century ago. Having owned an XK 150 for 48 years, I agree the E Type louvers create a special problem when it comes to rain, but I find the Barratt manifolds quite good for those who can generally avoid the wet. The beautifully enameled manifolds are part of what it makes an XK motor so special. We could paint the cam covers with barbecue black as well and not have to polish them, but most of us choose not to do that. With the prevalent concern about originality, let's not accept inferior alternatives. I'm still searching and willing to invest in the proper product. I think, if we supply the demand, someone will satisfy it. If we accept barbecue paint, the demand evaporates.

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Moeregaard
Posts: 763
Joined: Thu Mar 13, 2008 7:23 pm
Location: Thousand Oaks, California
United States of America

#28

Post by Moeregaard » Fri May 29, 2015 3:50 am

What we need is for someone to develop a porcelain finish that has a coefficient of thermal expansion identical to that of cast iron. Both of my E-types had their manifolds sand-blasted and repainted with hi-temp paint on a periodic basis, so I never really considered having the porcelain reapplied.
Mark (Moe) Shipley
Former owner '66FHC, #1E32208
Former owner '65FHC, #1E30036

Planning on getting E-Type No. 3 as soon as possible....

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

PeterCrespin
Posts: 4561
Joined: Fri Mar 05, 2010 8:22 pm
Location: Gaithersburg, Maryland.
Contact:
United States of America

#29

Post by PeterCrespin » Fri May 29, 2015 9:35 am

daykrolik wrote:Come on folks, this is simply ridiculous. I refuse to accept that in 2015 (the post space age) SOMEONE cannot offer a reasonably durable semi gloss black manifold coating which replicates and improves on that which Jaguar used over half a century ago......If we accept barbecue paint, the demand evaporates.
The original wasn't semi-gloss it was high gloss vitreous and therein lies the problem that, as far as I know, has never been solved by anyone, including Jaguar. Glass and metal do not expand co-linearly and once you get beyond modest cruising to the expansion differences caused by sustained higher revs the hot spots where the port flames hit the inside of the manifold runners and the area where runners 2&3 and 4&5 join gets so hot that repeated heating/cooling cycles cause cracking and eventual shedding of the coating even in the absence of bonnet louvres. You rarely see enamel shed from the flanges except by chipping because those areas stay far cooler and it's always the same sort of pattern following the heat gradients.

This is not ridiculous, it's physics (and a bit of physical chemistry I suppose).

I have never seen an original ceramic manifold that wasn't cracked and don't know of any current ones that survive hard use. Which leaves other types of finish that can last but are expensive and don't look totally original, or that are cheap and easy to redo and don't look original. The only combo you can't have is totslly otiginal 'wet look' ceramic and long-term hard use durability. You couldn't then and you can't now, because vitrified finishes and cast iron are still the same in terms of differential expansion AFAIK.

If the parts were steel then black chrome would be an option evrn though it doesn't have that thick wet look. But you can't get a true mirror finish on rough cast iron and even if you could put a heavy coat of copper on and polished that instead for black chrome, I don't know if it would all work out electrolytically or durability-wise for a finish that still wouldn't be exactly original.

Pete
1E75339 UberLynx D-Type; 1R27190 70 FHC; 1E78478; 2001 Vanden Plas

Link:
BBcode:
HTML:
Hide post links
Show post links


daykrolik
Posts: 63
Joined: Fri Feb 25, 2011 11:33 pm
Location: New York City
United States of America

#30

Post by daykrolik » Fri May 29, 2015 1:41 pm

The level of "semi-gloss" on the Barratt vitreous manifolds is awfully close to the original "gloss" on my XK 150. As I believe I have written previously, the manifolds on that XK150, which I put on in 1969, still looked nearly perfect in 2011 after approximately 50,000 miles of often very hard driving. I do understand the physics and chemistry and I do understand the water/louver problems unique to an E. I think it was obvious I was being facetious with the "ridiculous" comment. As I'm sure you're aware, Pete, there have been some extraordinary advances in high-temperature coatings since 1969. My primary point was that if we in the E community content ourselves with barbecue paint or other coatings which don't get close to replicating the original, purveyors will not be particularly inspired to find or develop better coatings which will be identical or close to the original.

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

PeterCrespin
Posts: 4561
Joined: Fri Mar 05, 2010 8:22 pm
Location: Gaithersburg, Maryland.
Contact:
United States of America

#31

Post by PeterCrespin » Fri May 29, 2015 5:56 pm

I wouldn't mind betting I could get your XK manifolds to crack :-)
1E75339 UberLynx D-Type; 1R27190 70 FHC; 1E78478; 2001 Vanden Plas

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

paydase
Posts: 546
Joined: Thu Dec 19, 2013 7:11 am
Location: Belgium
Belgium

#32

Post by paydase » Fri May 29, 2015 8:49 pm

daykrolik wrote:there have been some extraordinary advances in high-temperature coatings since 1969.
Once upon a time, I was in charge of the surface science and engineering laboratory of the french nuclear energy organisation.
To instruct our case, I will gladly share two examples of unsuccessful and successful surface treatments.

The first one was the failure to elaborate a coating that would have allowed to develop industrially the process of isotopic separation of uranium vapour by laser: no material could sufficiently resist to corrosion by liquid uranium, the Mendeleev table is not expandable...

On the other hand, we could successfully develop exceptionally resistant materials to abrasion by sand, for use in military helicopter turbine blades. These were made of very thin multilayered vapour coatings of tungsten and tungsten carbide, alternating a very hard carbide and a relatively ductile metal, both refractory. The micron scale of each layer, the chemical affinity of the layers using the same metal base and the very large number of layers made the trick. I will not tell the cost...

In the case of our manifolds, I am certain that sophisticated layered materials of metal and ceramics may do the job. But at which cost? Only space or military programmes can spend big money with no concern of ROI;) I would personnally advocate a much cheaper process to recover an acceptable semi gloss look or... live with my manifolds as they stand as far as they do the job!
Serge
1964 (3.8) FHC
1961 OTS

Link:
BBcode:
HTML:
Hide post links
Show post links


daykrolik
Posts: 63
Joined: Fri Feb 25, 2011 11:33 pm
Location: New York City
United States of America

#33

Post by daykrolik » Sat May 30, 2015 2:54 am

Honestly, Pete, I think I was lucky with that pair, which was only my second on that '59 car. But they were straight from Jaguar via Falvey Motors in Detroit. It was pre-'74 and I cruised for long periods in excess of 85mph and often over the ton. But my point is that SOMEONE, over 40 years ago, knew how to coat those manifolds to last. I think Barratt is on the right track. Perhaps I will talk to them and see if their product can be improved. I will also do some research. I believe the answer is out there. The cost may, however, turn out to be a problem. But if we supply a decent demand . . .

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

mgcjag
Moderator
Posts: 8070
Joined: Fri Jul 09, 2010 6:15 pm
Location: Ludlow Shropshire
Great Britain

#34

Post by mgcjag » Sat May 30, 2015 8:07 am

As i posted above have a look at Cerakote..they dont do a black gloss coat but talking to one of ther dealers it may be possible to use satin black and then gloss clear coat...but he wasnt sure....but a good start point from a product that states its No1 in high temp coatings Steve
Steve
69 S2 2+2 (just sold) ..Realm C type replica, 1960 xk150fhc

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Heuer
Administrator
Posts: 14744
Joined: Sat Mar 01, 2008 5:29 pm
Location: Nottinghamshire
Great Britain

#35

Post by Heuer » Sat May 30, 2015 9:12 am

The previous owner of my FHC had the manifolds done in black ceramic by Camcoat along with the entire s/s exhaust system in silver (for some unfathomable reason). Once I started 'driving' the car the ceramic turned to dust. I think they have now withdrawn the gloss version and only supply the satin black version which you can buy and DIY from Demon Tweeks: http://www.camcoat.com/main/coatings3.html

Zircotec offer something similar: http://www.zircotec.com/
David Jones
S1 OTS OSB; S1 FHC ODB
1997 Porsche 911 Guards Red

Add your E-Type to our World Map: http://forum.etypeuk.com/viewtopic.php?f=1&t=1810

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

paydase
Posts: 546
Joined: Thu Dec 19, 2013 7:11 am
Location: Belgium
Belgium

#36

Post by paydase » Sat May 30, 2015 6:14 pm

As already outlined by Pete, if you go for a ceramic coating on a metal substrate, you will always have the issue of differential dilatation.
Hence, as reported by David, the unguaranteed duration of ceramic coatings on manifolds because of thermal fatigue.

You can compensate differential dilatation up to some point through an adaptative layer and a non fully dense and fine grained ceramic coating. That will have a non glossy surface aspect.

Trying to "vitrify" that ceramic coating through extreme surface thermal treatment (e.g. plasma heating) will lead to a denser structure that will not sustain thermal fatigue and will eventually crack.
Serge
1964 (3.8) FHC
1961 OTS

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

Sarthe72
Posts: 228
Joined: Fri Oct 25, 2013 7:21 pm
Great Britain

#37 Re: re enamelling exhaust manifolds

Post by Sarthe72 » Thu Dec 13, 2018 11:42 am

An old subject, but it is so well known that driving an E-type over 60 mph will cause the enamel to crack. So, during the rebuild in 2014 we found that both manifolds were cracked and new ones needed. Instead of buying enamelled ones we bought plain and painted them with BBQ paint at a cost of £20. And the paint has lasted 7,000 miles despite hard driving and if I need to freshen them up I still have a lot left.

ImageNew engine 2014 by Tony Brown, on Flickr
Last edited by Sarthe72 on Fri Jul 26, 2019 3:20 am, edited 1 time in total.

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

politeperson
Posts: 1290
Joined: Tue Jun 07, 2016 8:26 pm
Location: Boston UK
Great Britain

#38 Re: re enamelling exhaust manifolds

Post by politeperson » Thu Dec 13, 2018 11:49 am

Like your style!
Its true, but Enzo never said it
Too many E types
XK120 SUs

Link:
BBcode:
HTML:
Hide post links
Show post links


christopher storey
Posts: 5698
Joined: Sun Mar 09, 2008 3:07 pm
Location: cheshire , england
Great Britain

#39 Re: re enamelling exhaust manifolds

Post by christopher storey » Fri Dec 14, 2018 11:09 am

Personally, I think your BBQ painted manifolds look just as good as the original high gloss , and are much more practical and durable . I anticipate that the original purpose of the vitreous finish was for show purposes - the XK engine exhibited at the 1948 show was quite stunning in its overall appearance . I cannot offhand think, however, of a single engine other than the XK which had this exhaust manifold finish

Link:
BBcode:
HTML:
Hide post links
Show post links

User avatar

PeterCrespin
Posts: 4561
Joined: Fri Mar 05, 2010 8:22 pm
Location: Gaithersburg, Maryland.
Contact:
United States of America

#40 Re: re enamelling exhaust manifolds

Post by PeterCrespin » Sat Dec 15, 2018 1:48 pm

I think there were enamelled parts on early engines, both exhaust and elsewhere - you see them on museum exhibits. But they were softly-tuned low speed primitive engines.

Vitreous enamel was of course standard on cooking hobs and baking pans/ovens, both cast iron and steel. It is excellent technology and being ‘heat proof’ as a material I can see why Lyons chose it alongside satin-polished alloy. He was a motorcyclist after all, where everything mechanical was on show and therefore a chance to style and impress.

I wouldn’t mind betting that if the manifolds could have been packaged to run straight out from the head for a foot or so, before curving gently, the glass-type coating would last forever. I have an original D-type tubular front manifold which is light as a feather and, being from an already tilted engine, has quite gentle curves. It appears to have some sort of gloss black coating but thinner. Instead, just as sith British chrome bike exhauststs, ours have a concentration of heat just where the hottest part of the flame hits the iron at a relatively thin point and the most acute angle. It would be interesting to see the isotherms on A good IR image of a manifold during a dyno run.
1E75339 UberLynx D-Type; 1R27190 70 FHC; 1E78478; 2001 Vanden Plas

Link:
BBcode:
HTML:
Hide post links
Show post links

Post Reply Previous topicNext topic