Subject: Re: Hi Compression?

Author: Douglas Welborn

Date: Jul 15, 2002, 3:04 PM

Post ID: 1710608679

165 would be normal for an Eldo, 195 is about right
for a Le Mans.

i wouldn't worry about it unless you are getting pre
ignition (knock) which
will probably be caused by something else anyhow.
does it run alright?

it could be your guages just read high. or you have
non standard pistons.

if you really need to get the carbon off, you might
as well take the
cylinders & pistons off as doing it with the
cylinders on will disturb the
base gaskets. scrape with copper scraper made from
flattened household water
pipe ( do you have coppper water pipe in US? i
dunno).

cookie



----- Original Message -----
From: "Alan Dunphy" <adun-@midmaine.com>
To: <Loopfram-@topica.com>
Sent: Monday, July 15, 2002 5:19 AM
Subject: Re: Hi Compression?

Vince,
Most likely, it would be carbon buildup on

the top of the piston
and

in the combustion chamber. Carbon can be the

result of constant speed
usage.

It will most times be accompanied by spark nock,

sounds like pins rattling

in the engine, especially under a load. There is

only one safe way to
remove

it, pull the heads off. Put a bit of grease in the

gap between the piston

and the cylinder then scrape the top of the piston

using care not to gouge

the metal of the piston. Cleaning the combustion

chamber will require even

more care not to gouge the metal or damage the

valves. Carbon is very

abrasive so be sure to get all the residue cleaned

out before reassembly.

Most of the grease will stay at the top of the

cylinder when the piston is

lowered and trap the grit making it easier to

clean. Gouges in the metal
can

cause hot spots and preignition (spark nock). If

you are not getting spark

nock with a good grade of high test gas your

problem is not as serious
and

may be cured with several hard accelerations

followed by equally hard

deceleration in second or third gear. The theory

being that the sudden

changes in combustion chamber temperature will

loosen the carbon and blow
it

out the exhaust. If the carbon build up is heavy

this method is used it
can

damage the engine if a large particle of carbon

gets caught in a valve on

into the ring area. Good luck with your solution.

Alan
'74 Eldorado LAPD Wixomized
MGNOC 4352

Alan R. Dunphy
adun-@midmaine.com
Pittsfield, ME 04967-1426

----- Original Message -----
From: <lio-@aol.com>
To: <Loopfram-@topica.com>
Sent: Sunday, July 14, 2002 11:18 PM
Subject: Hi Compression?

Today I checked the compression in my Eldo. Both

cylinders read 190psi.

If my memory serves me well this is a bit on the

high side. Does anyone

know the proper specs? If it is too high, what

might be the cause?

Thanks........ Vince in NY