At 08:27 AM 05/08/99 -0700, you wrote:
>
>Brian :
>
>Sorry to say this, but IMO you have busted rings (maybe even a busted
>piston) in #6. Which probably means the cylinder walls are shot, too.
>Randall
I'd be thinking along Ranall's line of thought. My TR6 started to foul the
rear plug really bad. Eventually it would foul in just a few minutes. Lots
of black crusty carbon.
After pulling the head, the cause was quite obvious...
The piston rings had broken up, and had been 'flopping about' in their
grooves. The constant 'flopping' had worn the groove wider, until the ring
bits escaped into the combustion chamber. They must have passed out the
exhaust, as the bits weren't there when I pulled the head. The piston top
had really neat little marks all over it, from where the bits of rings were
pounding...
Needless to say, the cylnder walls were seriouslt scored.
Nevetheless, all was well after a .020" overbore, and new pistons. (And
while at it, new bearings, new timing chain, new.... (you get the idea!)
Either way, pull the head, and you should know what's going on.
Regards,
>
>Brian Borgstede wrote:
>>
>> Well,
>> I pulled the plugs to see why the 250 had a miss.
>> I hoped to see the first three plugs to be one color
>> and the last three to be another. Not so lucky.
>> The first five plugs where a nice tan color, the
>> #6 plug covered in oil. Well, maybe the plug
>> fouled and quit firing and built up oil over time.
>>
>> The compression test...
>> cold engine dry
>> 90 150 170 140 160 and #6... Zero!
>>
>> Wet (few squirts of oil in spark plug holes)
>> 92 180 195 170 195 and #6... 7psi.
>>
>> I figure that #1 has a leaky valve,
>> I took the valve cover off to check #6 to see if the
>> valves where closing. The stems are going up and down
>> as normal.
>> My next step is to pump compressed air into the #6 hole
>> and find it's escape, (water, oil, intake, gasket, or exhaust)
>>
>> My plan was to drive the car for teh summer and start the
>> restoration this winter. I know that the head Has to come off,
>> and the rings are worn.
>>
>> Could I be missing something here?
>> Can I just drive it for the summer?
>> What kind of leak causes zero to 7psi. compression?
>>
>> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>> NEW E-MAIL ADDRESS: borgstede@umsl.edu
>>
>> Brian Borgstede I
>> Telecommunications Engineer, I '68 Triumph
>> University of Missouri, St. Louis I
>> Instructional Technology Center I TR-250
>> Phone: (314) 516-6433 I (or 2 or more)
>> Fax: (314) 516-5294 I
>
>
Frank de Kat
fdekat@sentex.net
Dundas, Ontario, Canada
http://www.sentex.net/~fdekat
To see "The Rally Pictures"
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