air bleed fitting for 120 Lehman

[Tator]

On another thread I saw mention of a way to fit an automatic air bleed to the return line of a Lehman 120. I have had a vary small air leak for many years on one of my Lehmans and have been unable to fix it. It takes about 50 hours of running to effect the Stbd engine only. Does anybody know the details of this setup? It seems like it might be the way to go.

Thanks, Tator

 

[Xsbank]

Take the copper washers out from under the bleeds and other fittings on your Simms pump and anneal or replace them. That was the source of a leak on my Lehman.

 

[Tator]

Thanks, but I've done all the obvious solutions over the years. It''s been 3k hours since I've bought the boat. The auto bleed line just sounded like an easy solution. I usually loosen the filter bleed screw every 30-40 hrs. just so I don't falter at an inopportune time.

 

[Capt.Bill11]

There way we used to do it was to remove the bleed screw from the top of one of the CAV engine mounted filters.

It's been awhile but as I recall it was the bleed screw located on the filter that was slightly higher due to the slope of the engine. The logic was since air would have a tendency to rise to the highest level that is where the air bleed off should be located.

As I also recall the the bleed screw hole had to be retapped to except the one way check valve used to bleed off the air. The outlet side of the check valve was T into the fuel return line.

We used to use clear hose for the line coming off the check valve so you could see any air flowing out of the check valve and being returned to the tank.

This system worked great.