Re: Question about lead

[Ray Bell <camberkits@xxxxxxxxx>]

Lead substitutes do not contain Tetra-Ethyl lead.

The issue at hand is lubrication of the (very hot) exhaust valve seat
area. And it's true that cars which had run leaded fuel for years can
continue to run unleaded if the valve seats are not cleaned up, it
does appear that the lead left a coating which provides that
lubrication or protection.

But once the head is cleaned up, seats cut, valves lapped in etc, this
is gone and something else is required.

I can assure everyone that the easiest way to deal with this without
taking the heads off is to fit a 'fuel catalyst' in the fuel line just
before the carburettor. This is a canister with pellets of tin
suspended inside with a steel spring, the fuel flows through this and
picks up the minute particles of tin that come off the pellets due to
their rubbing (with engine vibration) on the steel spring.

The tin provides the same reaction in the combustion chamber as lead
did and protects the valve seats. Manufacturers also say it raises the
octane level, which could well be true, but I don't know.

I have, however, fully tested these things with regard to valve seat
erosion. They stop it dead! I had a head which was fine with its
residual lead, then I damaged the valve (a piston fell apart, a piece
of ring lodged in the valve seat) so that seat had to be cut and the
valve lapped in. Immediately I had the problem of valve seat erosion.

The valve seat was losing 0.010" to 0.015" per week with my high
mileage driving, I was adjusting the valve clearance once a fortnight
until I got around to fixing it. I put a head in to be rebuilt using
hard seats but it wasn't ready in time, so I fitted another head in
which I cleaned up all the valves and seats. I ordered a catalyst to
fit with that and it necessitated just two days of driving before I
would get that.

In the two days I covered 900 miles, each exhaust valve required
0.015" of adjustment. I fitted the catalyst when it arrived in the
mail and didn't have to touch the valves for another 50,000 miles.

I make no claims about the octane improvement or pinking reduction, I
never had to worry about that, but for protection of valve seats I
guarantee these things work. You could actually make one yourself,
they are simple.

Ray



On Jan 16, 11:39 pm, Dave64 <lt7d...@xxxxxxxxx> wrote:
> I've been running lead additive with every tank and 91 octane gas since it has no ethanol.  Runs like a top.
>
> Dave
> '64 Belvedere 2DHT
> 318 Poly, Push Button Auto
> Originally Florida A/C Car

-- 
--
Please address private mail -- mail of interest to only one person -- directly to that person. That is, send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic.  Thanks!

1962 to 1965 Mopar Clubhouse Discussion Guidelines:
http://www.1962to1965mopar.ornocar.org/mletiq.html and http://www.1962to1965mopar.ornocar.com/general_disclaimer.html.
-- 
You received this message because you are subscribed to the Google Groups "The 1962 to 1965 Mopar Mail List Clubhouse" group.
http://groups.google.com/group/1962to1965mopars?hl=en.