Leaking fuel pressure switch Westerbeke W30

[sanibel sailor]

after several years of a slight fuel injection pump leak and multiple fruitless attempts to fix it (2 or 3 seal kits so far) it finally seems to have gotten bad enough to allow correct diagnosis as a leaking fuel pressure switch.

The original Westerbeke 11383 part number is obsolete, replaced by Westerbeke 37323, with a 1/8-27 NPT thread and a normally open switch, closing at 10 lbs. It is $18 at TOAD Marine Supply, but they won't ship here. I did a bit of Googling and found a oil pressure switch from a 1985 Chevy C10 truck with a 350V8 will work. Closing pressure is a little lower at 4+/-2 psi, but it seems to work as intended. The neck is a little longer as well which just made installation a bit easier.

Part numbers are S371 (or S371P) from BWD or Duralast PS115. I believe a Motorcraft SWG1702 may work as well. Less than $10 and in stock at the local auto part store.

Time will tell, but I am hopeful this may be the end of my leak. It has been a real nuisance as enough fuel leaks out of the pump that I have had to bleed it if it sits too long.

[CS Cruiser]

John, did you get chance to replace the fuel pressure switch with the alternate you mentioned from auto parts? Did it take care of the leak?

[zboss]

Contact First Mate Yacht Services in St. Augustine... they are the official distributor for WB in FL. Talk to Trish... awesome customer service. Even if you do not buy from them they will have a technical discussion with you regarding the part. Canot hurt.

[S/V Antares]

The Perkins (W30 base) uses a CAV pump the little plate on the side leak as it is a crappy gasket arraignment. I believe the pressure switch is a Hobbs switch which is available in various make points NO or NC

[zboss]

Are you sure its a perkins? My engine (W46) was made using two different blocks. Check on your engine for a plate.

[sanibel sailor]

It is not a Perkins but a BMC (British Motor Corp aka British Leyland) block with a CAV DPA rotary pump. Pump is similar to a lot of Perkins pumps, but has a different governor arrangement and no little side plate as shown above.

I did replace the switch two days ago. When I stopped by yesterday, there was one or two drops in the catch bowl I have under the pump. I am hoping those were "leftovers" from bleeding. Maybe not. At least it is not the steady drip as before.

[S/V Antares]

Woops....Thought it was Perkins. English, though and close. W-Beke did use the Perkins 4-107 & 4-108. as base engines. They are Misubishi and Kabota these days.

Hope the leak is fixed. can be real frustrating.

[egrina]

This Saturday I came to the same conclusion about the fuel pressure switch on my Westerbeke 40 leaking. Amazingly within Marion Harbor where I'm located at 2 pm on a Saturday afternoon I found that switch (WB03723 - $20 from Burr Bros) and installed it. No more fuel leaks. However a second ongoing problem that I thought related has not been solved. After shutting down for only a few hours we can still start, but overnight we become air-bound. Engine spins great but won't start. Cracking injectors, a different one or two each time, is sufficient to get started.

Could air leak in past the new switch's threads? (I didn't use any thread lock or Teflon tape.)

I've checked for loose fittings between the tank and Racor, Racor to lift pump, lift pump to secondary filter and secondary filter to injection pump, everything seemed tight.

The thought of having to take all those connections apart and remake them, along with the filters, is a daunting prospect. I'd ppreciate any suggestions anyone might have on how proceed from here. Thanks.

[sanibel sailor]

Mine had done that after sitting a week or more and did it once after switch replacement but not since. When it was acting up, I found if I ran the electric pump for a bit prior to attempting to start, it would not die.

Maybe it will not happen again.

[egrina]

John,
Thanks for your words of encouragement - I haven't gone beyond the first post-switch replacement start up when she needed to be bled again. We left the boat this afternoon and Wednesday I'll try again to see if she's air-bound again.