Hi all:
We've had our 38 Ocean for about 1 1/2 years. Throughout the time we've owned "Yondigo", we have strived to establish baselines on the maintenance of the boat (no maintenance logs). So many routine items completed I won't list them all here.
As what seems to be normal for the MD22, we had a fair amount of fuel smoke upon initial start of a cold engine. This would always leave some sort of fuel sheen on the water. Not an alarming amount of fuel sheen but, more than other boats we had owned or been guests on.
Reading through various forums, we deemed the amounts of smoke and fuel sheen "typical" for the MD22. As well, it started and ran just fine with fuel consumption close to what others are reporting.
Working our way down the list of "baseline" items, we decided to replace the fuel injector nozzles. Testing the nozzles that came out of the engine (pretty sure original) the spray pattern was more of a squirt that a misting pattern. Installed new nozzles in the injector bodies, tested and the spray pattern was a fine mist/fog. Certain this would fix our smoky engine we were surprised that it actually made it worse...MUCH worse!
Next baseline job was to replace the timing belt and pulleys. I figured that while doing this job, we'd finish up by checking the timing on the high pressure fuel pump. Here I ran into a bit of an issue. Following the workshop manual instructions and tensioning the timing belt to the proper tension, the ability to lock the camshaft and flywheel in the Top Dead Center position was not possible (it was possible with the old timing belt). After some investigation, I noticed that the cam and flywheel locking/alignment holes were about .02mm away from lining up, or being out of alignment.
Decided to skip the fuel pump timing and see what results the new and properly tensioned timing belt would give us because of the alignment issue. The thought was that could very well have some affect on the fuel pump timing.
The start was maybe 2 full rotations and it fired off. Some smoke, as expected due to rotating the engine by hand while replacing the timing belt (sending fuel into cylinders without ignition) but quickly subsided. Subsequent starts and bringing the engine to normal operating temperature, the smoke is nearly gone and no fuel sheen...even on starts.
This is one thing I have never read online. Check the timing belt tension. It does affect the fuel pump and it's timing! Best thing about it is that most owners can do this themselves and can easily be part of annual maintenance. All that said, if you seem to see more smoke over time, I would first check the timing belt tension.
