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| | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | Ok so I get the following results
(these are new plugs)
cyl 1 120# plug is tan
cyl 2 120# plug is tan
cyl 3 110# plug is black
cyl 4 110# plug is black
cyl 5 110# plug is tan
cyl 6 118# plug is black (little oily)
I tested each cylinder twice and there was little variation. I was not able to see the pressure come up (to check for valve issues)as I was doing this alone and couldn't crank and watch the gauge at the same time.
These readings seem high. I do get black carbon out of the exhaust. The plugs were better after driving for some time. I have only driven it a few dozen miles but lately I have been working on it and it just runs in the driveway.
If this is due to carbon build up in the cylinders will it resolve over time driving it more frequently?
Rich
| | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | Actually, those readings are about right. On the low side on 3,4,and 5, but still within specs. The carbon is most liley from a rich condition, may need to look into the carb for float hight and/or clogged passeges. The oil on #6 might be a valve guide seal.
Bill Burmeister
| | | | | Joined: Apr 2009 Posts: 29 New Guy | | New Guy Joined: Apr 2009 Posts: 29 | I recently had a valve issue and a blown head gasket on a 235 (had a blown head gasket post) and after replacing head gasket and cleaning valve stems and guides, and lapping the valves I have 118# to 105# on all six. I hope those numbers and yours are good -- I'll be interested to see. My plugs where also black and I got alot of feed back like running to rich or burning oil. I believe the tan plugs are burning correct so I do not how 3 could be good and 3 too rich unless you too have some sticky valves but your compression is good. I'm still learning able this stuff so hopefully someone with more knowledge will answer . I most have been posting at the same time as longbox so we both got an answer to the compression number guestion
Last edited by chevymgb; 08/12/2009 3:14 AM.
| | | | | Joined: Sep 2005 Posts: 1,028 'Bolter | | 'Bolter Joined: Sep 2005 Posts: 1,028 | I have had a lot of carb problems and even bought a new one which turnded out to be defective so I returned it. I have adjusted my old (rebuilt)carb many times but it can't seem to run consistantly.
I am glad my compression readings are ok. I was not able to find the spec in the book and I read here that the spec was 110#.
Thanks
Rich
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