Westerbeke Gas 7.2 starts but immediately shuts down

Read through some of the old posts and thinking it could be a sensor and most likely oil pressure. It ran fine prior to this-they all do! I go through my normal starting sequence of click on tap start wait for it to prime-shut switch back off then back on to crank. Extended crank-always did that and as soon as it fires i release the starter and it will run for about 2 seconds and shut down. Light starts blinking fast on the start rocker switch. I tried it 4-5 times and same exact thing. Runs for a second and shuts down. All fluids are fresh this year and at proper levels. The immediate shut down makes me think that it might not be detecting oil pressure. Would the other sensors (if bad) let it start for a couple seconds then shut it down?
I don't have a preheat switch on the panel that overrides the safety's. I hear the switches on the genny itself may override the safetys. I've never tried starting it from those. I plan to "jump" the terminals and see what happens.
1998 Westerbeke Gas 7.2 BCGTC carburetor with 3-400ish hrs.
Any other thoughts?

Go to westerbeke's site and download the operating manual.

Yes, you probably have a oil pressure sensor gone bad. They do fail. Also, check the electric fuel pump. If it's not working, it will create the same problem.

For the long cranking problem, you have a coil going bad. If you buy one from westerbeke, you're looking at $500. However the auto parts stores carry the same coil for $30.

CaptRonn said:

Go to westerbeke's site and download the operating manual.

For the long cranking problem, you have a coil going bad. If you buy one from westerbeke, you're looking at $500. However the auto parts stores carry the same coil for $30.

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I'm having this long cranking problem as well, it's a 7.0 BCG from 1997. My parts manual says it's #037968, and sure enough an online search is showing over $500 for it. Can you point me in the direction of an alternative part?

Try cross referencing the part number. Mine is a two cylinder and I found that a Harley Davidson coil works on it. Sometimes you get lucky

Hey Ray said:

I'm having this long cranking problem as well, it's a 7.0 BCG from 1997. My parts manual says it's #037968, and sure enough an online search is showing over $500 for it. Can you point me in the direction of an alternative part?

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Search my past post, I wrote about it not long ago and identified the part I used.

I’m on an iPhone on the boat right now. But take a look. Look at yours (it’s on a Westerbeke mount) and look up the part online, it should look identical.

Well after analyzing tonight looks like the fuel pump. It quit making the cycling clicky noise and no longer even fires. Of course it’s buried on the bottom back. Anyone ever change one?

In my humble 17 years of experience, the long start is because the choke solenoid is not engaging. If you pay for a new one, that will work for a "bit", but is not a long term solution. This is a 2 person job.
one in the bilge looking at the linkage around the carb and another in the cabin trying to be an owner.
if the choke solenoid and/or the electric fuel pump are not kicking in when the "owner" is trying to start the genset, you have discovered your issue. If I get that solenoid to pull, it starts every time.
Here is your 2020 present if you have a 7.0BCG
https://www.dropbox.com/sh/m4wtgsdif0zi5jx/AADpvR7y_r1JvTtepVs40lZba?dl=0

Skuza said:

Well after analyzing tonight looks like the fuel pump. It quit making the cycling clicky noise and no longer even fires. Of course it’s buried on the bottom back. Anyone ever change one?

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When the marina changed mine, they unbolted the mounts and rotated the entire genny to make it accessible....

Skuza said:

Well after analyzing tonight looks like the fuel pump. It quit making the cycling clicky noise and no longer even fires. Of course it’s buried on the bottom back. Anyone ever change one?

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Facet or a knock off. They will continue to fail. 12V spec 2-4 GPH low pressure electric pump. I've used Autozone pumps with the same expectancy and performance. The only true solution to this is constant babysitting. In my humble 17 years of experience......

Chris-380 said:

When the marina changed mine, they unbolted the mounts and rotated the entire genny to make it accessible....

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I might try unbolting the hot water heater that is next to it and moving that outta the way. Might give me enough room. Being 5’7”-170lbs is gonna help too

New question. Re-use the hard fuel lines copper with brass nut and ferrule? Will they seal again?

In addition the pump is off and runs on 12v-go figure! I’m gonna change it anyway. I tested for 12v when it was still on and it was getting to the connector. I don’t recall if I checked for ground and it’s making me wonder.
Also there is a screw on the bottom of the generator holding the pump on. WHY?? I had to pull the 4 lag bolts and was lucky I could tip the generator to reach it.

Skuza I have Longitude Marine working on mine right now (waiting for parts). Mine would just crank and not start. I was thinking fuel pump also but I didn't want to tackle it because of the location of genie and time. They found a bad temperature sensor and the main reason for not starting is the choke sensor as 370 said. Good luck with yours. Longitude Marine is out of St. Clair Shores and Steve's number is 810-240-0495 if you need more assistance. So far I'm real happy with them. I'll try to check back in on this thread when mine gets running and let you know the outcome.

To finish this project here is what happened-
The oil temperature sensor failed. It was shorting itself out internally and grounding one of the leads. It took out the fuel pump circuit and that is why it would not run. Initially it would run for a second then quit. I figured the fuel pump was bad and removed it-fun as I had to remove the mounting bolts and tilt the generator to access the one screw on the pump that is located on the BOTTOM of the engine. Once off I bench tested it and it ran fine! I remounted it and now had an issue that the overspeed circuit board inside the electrical box on the generator was shorting a diode and smoking! This happened while attempting the starting sequence and waiting for the fuel pump to prime-the fuel pump however was NOT priming due to the shorted out sensor. The shorted out sensor was frying the diode on the overspeed board. I initially thought that was a seperate issue and was wondering what was now causing that! It was the shorted out sensor. A local electronic shop changed out the burned diode for $30. I found the shorted sensor by process of elimination-unpluggin sensors until the smoking diode went away. As soon as I got to the oil temp one and unplugged it the fuel pump ran during prime cycle and no more smoke! New sensor was $83. Runs fine again.
Sometimes when you imagine the worst its the simple thing! Took 1 minute to change. Start with the easy stuff first. Had I known how to properly test all the sensors in the first place I woulda saved myself a lot of grief!

Nice follow up. Glad its working. At least you learned where all the sensors are and wiring.

bone354 said:

Nice follow up. Glad its working. At least you learned where all the sensors are and wiring.

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Ya when you are at a dead end and figure something out its a thrill. Especially when its cheaper than you expected too. I brushed up on my wiring diagram skills too.