TWL: Fuel problem solved
At least I think I have found the culprit - a mismatched fitting that is
allowing air into the fuel lift pump. We have had intermittent engine
stoppages over the past two years (some of them in the worst possible places
at the worst possible times of course.) I was almost ready to bite the
bullet and have the tanks cleaned even though my filters always looked new
when I changed them out. It was baffling. I did install a racor vacuum
gauge as I report here on the list and it barely rose of the peg...but still
the engine would die from air in the injector. Finally during the last
cruise I replaced the fuel lift pump with a spare and that is when I
discovered that the fitting on the supply line was not long enough and
bottomed out on the hex shoulder before the flares mated. Seems as though
the Lehman has slightly deeper ports on the fuel pump and the fittings have
to be correspondingly longer. At least I think I have the problem
solved....but then I'll need to find a current ridden lee shore in a howling
gale and hand around there for and hour or so to find out. :)
Ron Sallee "Arwetheryet" CHB 34 Everett, WA
The lift pump on the Lehman-Ford engines do have a strange female fitting on
the inlet side. Bob Smith makes a special male flare fitting to solve the
problem, but it didn't solve it for me. If you have a top outlet fuel tank,
the pump will suck air as Ron's did. If you have a bottom feed tank, you
will get a very slow diesel fuel leak that will drive you crazy. I chased
mine for two months.
The solution is ridiculously simple. You can go to a diesel injection shop
and get a copper washer that will fit very nicely around the male flare
fitting. It will seat perfectly between that male fitting and the face of
the female fitting in the pump. Then normal torque will deform the washer
for a perfect, and diesel tight, fit. No more leak. Just get a few of the
washers so you will have them on hand if you need to disconnect the fitting
for any reason.
As an alternate, the lift pump on the Lehman-Ford is common configuration
for many engines of its power rating. The outside of the pumps may not look
alike, but the working parts are identical. Any good diesel shop will have
one or more brands that will work just fine. All of them I have seen don't
have fitting mis-match problem. Most of those shops can cross reference the
pumps they sell with the Lehman-Ford.
Good Luck!
CaptnWil
[SNIP] Finally during the last
cruise I replaced the fuel lift pump with a spare and that is when I
discovered that the fitting on the supply line was not long enough and
bottomed out on the hex shoulder before the flares mated. Seems as though
the Lehman has slightly deeper ports on the fuel pump and the fittings
have
to be correspondingly longer.
Hi Ron
I just found a source for vacuum gauges under $10.00. Could you tell me the
size (diameter of the dial) and the pipe size of the Racor gauge you got and
what they cost. I have heard it is about thirty dollars
Thanks
David Keese
Houma, La
alabat
----- Original Message -----
From: Ron Sallee ron.sallee@kendra.com
To: Trawler World List trawler-world-list@samurai.com
Sent: Wednesday, October 06, 1999 11:34 AM
Subject: TWL: Fuel problem solved
At least I think I have found the culprit - a mismatched fitting that is
allowing air into the fuel lift pump. We have had intermittent engine
stoppages over the past two years (some of them in the worst possible
places
at the worst possible times of course.) I was almost ready to bite the
bullet and have the tanks cleaned even though my filters always looked new
when I changed them out. It was baffling. I did install a racor vacuum
gauge as I report here on the list and it barely rose of the peg...but
still
the engine would die from air in the injector. Finally during the last
cruise I replaced the fuel lift pump with a spare and that is when I
discovered that the fitting on the supply line was not long enough and
bottomed out on the hex shoulder before the flares mated. Seems as though
the Lehman has slightly deeper ports on the fuel pump and the fittings
have
to be correspondingly longer. At least I think I have the problem
solved....but then I'll need to find a current ridden lee shore in a
howling
gale and hand around there for and hour or so to find out. :)
Ron Sallee "Arwetheryet" CHB 34 Everett, WA