Lotus Elan and Lotus Elan Plus 2 Forums

Hello all.



We are pulling the head on my Elan Twin Cam..the car that we drove from
Seattle to Kansas City.when the water pump gave out.



We are replacing the water pump..this time without pulling the engine as we
are just out of room to put the hoist.





Anyways.



After pulling the head..I noticed a great deal of carbon buildup on the
pistons.and on the chambers.



Should I clean this..both on the head and on the pistons.. Car was running
great.



Could this be because I was using Octane boost on the way cross country?



If I am to remove this carbon build up..what is the best way.?



I have not pulled a head on these in about 10 years.



Tony V

www.lotusowners.com

Tony- does a new engine come supplied with a carbon coating? No, remove it!
For a solution, check the archives for "Redex", we had a discussion on thisa while back (maybe 2 months ago) but I'm not sure if we found out if it is available on your side of the water; there must be something similar though.

Cheers,

Pete
----- Original Message -----
From: Tony Vaccaro
To: ***@***.*** ; ***@***.***
Sent: Sunday, November 14, 2004 4:23 PM
Subject: [LotusElan.net] Pulling Head on Twin cam


Hello all.



We are pulling the head on my Elan Twin Cam..the car that we drove from
Seattle to Kansas City.when the water pump gave out.



We are replacing the water pump..this time without pulling the engine as we
are just out of room to put the hoist.





Anyways.



After pulling the head..I noticed a great deal of carbon buildup on the
pistons.and on the chambers.



Should I clean this..both on the head and on the pistons.. Car was running
great.



Could this be because I was using Octane boost on the way cross country?



If I am to remove this carbon build up..what is the best way.?



I have not pulled a head on these in about 10 years.



Tony V

www.lotusowners.com

Tony
I have just had my twink out to replace the clutch ,whilst it was out I didthe usual bits waterpump new gaskets etc .The engine was out about 5yrs ago for waterpump ,I needed to decoke the head and pistons both times ,I used a rotary wire brush.The carbon was soft ,I think it is due to the Webers putting in excess petrol which is not burnt properly
Regards John 1969S4 DHC
----- Original Message -----
From: Tony Vaccaro
To: ***@***.*** ; ***@***.***
Sent: Sunday, November 14, 2004 4:23 PM
Subject: [LotusElan.net] Pulling Head on Twin cam


Hello all.



We are pulling the head on my Elan Twin Cam..the car that we drove from
Seattle to Kansas City.when the water pump gave out.



We are replacing the water pump..this time without pulling the engine as we
are just out of room to put the hoist.





Anyways.



After pulling the head..I noticed a great deal of carbon buildup on the
pistons.and on the chambers.



Should I clean this..both on the head and on the pistons.. Car was running
great.



Could this be because I was using Octane boost on the way cross country?



If I am to remove this carbon build up..what is the best way.?



I have not pulled a head on these in about 10 years.



Tony V

www.lotusowners.com

I would


probably not but I've seen some octane boosters leave odd coloured
deposits...looking more like iron oxide than carbon.


someone suggested a rotary brush but be cautious of overly stiff
bristles gouging the soft alloy. if the carbon is soft a handheld brass
or stainless brush and a bit of solvent will do nicely, for stubborn
bits try an old feeler guage.


Time to refresh yourself As long as the head is off you could check
the valve seating surface, guide condition etc, then hand lap all the
valves.

Cheers,
Scott




__________________________________

Check out the new Yahoo! Front Page.
www.yahoo.com

There was a great suggestion a few weeks ago about this.

To stop carbon falling between the piston and rings, drop the piston down by
1/2" and add a layer of grease into the corner. When all the carbon has been
removed move the pistons further down the bore and wipe away the grease!

David

-----Original Message-----
From: scott potter [mailto:***@***.***
Sent: 14 November 2004 16:53
To: ***@***.***
Subject: Re: [LotusElan.net] Pulling Head on Twin cam




I would


probably not but I've seen some octane boosters leave odd coloured
deposits...looking more like iron oxide than carbon.


someone suggested a rotary brush but be cautious of overly stiff
bristles gouging the soft alloy. if the carbon is soft a handheld brass
or stainless brush and a bit of solvent will do nicely, for stubborn
bits try an old feeler guage.


Time to refresh yourself As long as the head is off you could check
the valve seating surface, guide condition etc, then hand lap all the
valves.

Cheers,
Scott




__________________________________

Check out the new Yahoo! Front Page.
www.yahoo.com

--- In ***@***.***, "Tony Vaccaro" <tvacc@l...> wrote:
...After pulling the head..I noticed a great deal of carbon buildup
on the pistons.and on the chambers. Should I clean this..both on the
head and on the pistons.. Car was running great...If I am to remove
this carbon build up..what is the best way.?
--------------
Tony,
I think a drill driven rotary wire brush would be fine as long as you
use a "very light hand" to avoid eating up the aluminum combustion
chamber.

I've never run it in my twincam, but my modern V6 daily drivers get a
bottle of Techron concentrate, a Chevron additive, in the gas tank
every 3,000 miles to clean/keep the carbon out of the combustion
chambers. At full strength, this concentrate might be just the
ticket for a copper scouring pad hand-scrub clean-up of the
combustion chambers. Usual disclaimers - no links to Chevron, et al.

Best regards,
Paul Garrett
----------------