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polar21
06-16-2010, 12:35 PM
After I had my carb rebuilt and put on a new fuel pump, I believe I have finally found my problem with not getting the boat to crank. Using a 12v test light, I found that the fuel pump is not getting power to it. I went back and re-read my thread posted a while ago about the fuel pump safety switch. Could this be the culprit of the fuel pump not getting power? Seems like the next logical thing. Anyone know where I could find a "marine" type? The last one I put on there was an automotive type and I believe that is why it failed.

mikerudamann
06-16-2010, 10:09 PM
I have a 2001 Outback and have replaced the carb once and the fuel pump twice. I added a water/fuel separator as well as treating the gas (10% ethanol blend) with daily use Sta-Bil. Once I got all this straight, the thing still wouldn't start.

Using the test light method, I found that the fuel pump power feed came from a little unit called an oil pressure sending unit that supplies power to the fuel pump. After I replaced that I have had no further problems.

AaronWhitt82
06-16-2010, 10:22 PM
After I had my carb rebuilt and put on a new fuel pump, I believe I have finally found my problem with not getting the boat to crank. Using a 12v test light, I found that the fuel pump is not getting power to it. I went back and re-read my thread posted a while ago about the fuel pump safety switch. Could this be the culprit of the fuel pump not getting power? Seems like the next logical thing. Anyone know where I could find a "marine" type? The last one I put on there was an automotive type and I believe that is why it failed.

The fuel pump should only run while cranking the motor or while the boat is running.
The way the cut off switch works is when the boat is running or under a load the switch has to sense oil pressure in the motor and if it drops below a certain PSI (I don't remember what it is) the switch cuts power to the fuel pump.
Make sure you have a good connection to the fuel pump and follow the wires all the way back and make sure there is a good connection. I believe the wires also plug into the electric choke then they run back into that black breaker type box.
Then you have the 3 wires that run off of the safety switch.. (Red, purple and orange.)
Red should be power, orange is off the starter and purple is ignition.
I would also check the connections to your ignition.....

Here is a few links for the switches:

http://www.jamestowndistributors.com/userportal/show_product.do?pid=13957&familyName=Low+Pressure+Oil+Safety+Shut-Off+Switch

http://www.amazon.com/Mr-Gasket-7872-Safety-Switch/dp/B00068OQ3S

polar21
06-17-2010, 09:57 AM
thanks for the links Aaron. O'reiley auto parts has an automotive version of this part, but the housing gets corroded rather quickly. I am assuming that the Sierra one should hold up better.

AaronWhitt82
06-17-2010, 10:53 PM
thanks for the links Aaron. O'reiley auto parts has an automotive version of this part, but the housing gets corroded rather quickly. I am assuming that the Sierra one should hold up better.

After looking more closely at the Sierra one it looks like it is a bit shorter than the one at Amazon so not sure if it will work as far as clearance goes.... I'm not sure if there is actually a marine version of it either. I replaced mine a few years ago and it is an automotive one.

polar21
06-18-2010, 12:06 AM
Good deal. I put the new relay switch on tonight and the boat cranked up. It was a nice sound to hear the 350 purring again, although the carb still needs to be adjusted correctly. Going to give it a go this weekend. It has been a rough month for the Moomba. I think I have dropped a total of nearly $600 on the boat in the last 4 weeks. Oh well, its all fun and games until the wife sees the bills......

AaronWhitt82
06-18-2010, 12:29 AM
Good deal. I put the new relay switch on tonight and the boat cranked up. It was a nice sound to hear the 350 purring again, although the carb still needs to be adjusted correctly. Going to give it a go this weekend. It has been a rough month for the Moomba. I think I have dropped a total of nearly $600 on the boat in the last 4 weeks. Oh well, its all fun and games until the wife sees the bills......

Good to hear.... I hear ya on that part. Dropped close to $500 on mine.
New coil, cap, rotor, fuel pump and prop.