SailNet Community banner
1 - 1 of 1 Posts

699 Posts
Reaction score
Discussion Starter · #1 ·
I am trying to "connect" several symptoms regarding our Yanmar 4jhte and what seems like several symptoms being potentially one sue. We know there is a Mixing Elbow needing to be replaced. We have an overboard stream from the mixing elbow's anti-siphon that is usually a trickle, and now is a strong flow. This stream comes from the anti siphon, but the water comes from where our Osco Mixing Elbow "T" is, and is discharged separate from the exhaust at the stern.

The strong flow from the anti siphon indicates there is buildup n the Mixing Elbow. We have noticed in the last 50 engine hours or so, significantly more fuel usage for the RPMs, and a lower maximum RPMs if we push to full power. It seems to be running fine at 1,800-2,000 RPMs, but the maximum is less than 2,500. We have traditionally calculated 1 Gallon per hour at the lower RPM, and now we are using significantly more.

There is a small leak of fuel from the fuel return line. Could that have anything to do with the Mixing Elbow being obstructed? It is possible this is a separate issue, but I have tightened the small fuel return hose clamps and inspected the hose, and am still getting a leak. I know normally there is very low pressure on the fuel return lines.

So in summary...mixing elbow has buildu and needs service....simultaneously we are seeing lower maximum RPMs and higher fuel usage, and a small fuel leak in the fuel return lines. Are those other symptoms likely to be related? (Note: The small fuel leak in the return lines is not responsible for the higher fuel usage as it totaled less than 1 cup on a 24 hour motoring trip.)

Thanks gurus!
1 - 1 of 1 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.