Cylinder #1 carbons up

[Renegade]

I have had my A4 running perfectly for 9 years now. This summer we noticed a lot of soot from the exhaust on the stern after running a short period of time but there was no noticeable difference in the performance of the engine. I have installed the pertronix distributor and ignition with the matching coil, electric fuel pump, all from MM. In addition, I installed the PCV valve and oil filtration system from Indigo. I use Auto light 86 plugs, Atomic 4 wires from Westerbeke. I changed the rotor and cap, the plugs gapped at 030 and the wires and no change. All the upgrades have been on the boat for several years.

The compression on all cylinders is 110 cold and 105 warm. On the advice of a mechanic, I added some oil to cylinder #1 and cold the compression only went up to 115. My under load, maximum RPM is 2000 and cruising at 6kts about 1800 seems to be the sweet spot where the engine is happy. The engine runs at a temp of 160 to 170 in the summer and 120 to 140 in the spring and fall. There is no noticeable oil consumption between oil changes.

I follow the MM maintenance recommendations faithfully including using MMO in the gas and oil. Any ideas? I'm at a loss

[joe_db]

#1 as in the front of the engine?
Usually it is the other end that does that.

[Renegade]

yes the #1 front cylinder.

[roadnsky]

IMHO all of your "numbers" seem just fine.
Still not understanding the mechanic's logic in adding oil to the cylinder tho

Here is a suggestion from one of our guru's (Dave Neptune) that might help with the soot...
"I have been gapping my plugs at .038~040" (larger gap acts a bit like a hotter plug)
Take advantage of the EI by opening up the plug gap a bit .040"

[joe_db]

Originally Posted by roadnsky

IMHO all of your "numbers" seem just fine.
Still not understanding the mechanic's logic in adding oil to the cylinder tho

Here is a suggestion from one of our guru's (Dave Neptune) that might help with the soot...
"I have been gapping my plugs at .038~040" (larger gap acts a bit like a hotter plug)
Take advantage of the EI by opening up the plug gap a bit .040"

If you add oil and do a compression test, the number goes up if the rings are leaky and don't change if not

[roadnsky]

Originally Posted by joe_db

If you add oil and do a compression test, the number goes up if the rings are leaky and don't change if not

Ahhh, I get it now.
I mis-understood what he was doing. I thought he was adding oil to deal with the soot.
Gotta stop posting before I've had my coffee!