Westerbeke 7.2 BCGTC Blowing 8A Fuse

Wire T7 feeds (only) the Choke Solinoid and K2-Run relay (powers ignition and fuel pump). One is drawing too much current. Disconnect K2-Run relay. Test if fuse blows with relay out of the circuit. If it doesn't, test relay. Relay coil = 85 ohms. If the choke sol. is bad, you can leave it out (disconnected), manual choke first few minutes.
 
beware of a few new things im just replacing the engine on a 5.0 its a 3 cylinder 8hp 3100 hrs the engine has a catalytic converter built into the exhaust manifold that has a 2000 hr life this one plugged up and slowly killed the engine. the new engine was half the cost of rebuilding, parts are wicked pricey for a tiny 8 hp Mitsubishi industrial engine 500 for just the gasket set
 
OK; I finally got around to taking a look at this Westerbeke 7.2 BCGTC and the 8 amp fuze blows when the ON (preheat) switch is turned on if the T7 line is connected to the control board. I checked the components on the T7 circuit and here is what the ohmmeter shows (2 numbers are the resistance for each leg to ground):

Water Temperature Switch: 2.6 ohms left / 2.6 ohms right. Across both 0.2 (switch closed)
Oil Pressure Switch: 2.8 ohms top / Open Circuit (bottom) / Open circuit across both
Fuel Solenoid: 80 ohms
Choke Solenoid: 12.4 ohms
Exhaust Temperature Switch: Open Circuit to ground on both legs / Closed switch across both terminals
Hour Meter: Open circuit to ground on both legs / Closed circuit across both legs

Latest wrinkle in all this; when I pulled the T7 line from the control board and hit the ON switch, the fuze didn't blow which indicated a short on one of the components listed above. Now after all the pulling wires and checking the fuze with the ON switch, every time I simply put a new fuze in, you can see an arc in the fuze holder and the fuze blows. I'm thinking this might be a short in the circuit board.

Thanks for the help.

Brian
 
"NEVER" use a bigger fuse to overcome what is likely a short or malfunctioning device. The purpose of a fuse is to protect the circuit and prevent a fire from overheating overloaded wiring!!!!!!

I believe you have enough good advice to track down the actual problem.

Good luck and stay safe.
 
I said disconnect the choke solinoid and test if the short is gone, not measure the resistance. Next remove the K2 Run relay and test. If fuse doesn't blow, the relay is probably shorted. The other items do not matter as they are not in that circuit. My remark about a larger fuse was a joke.
 
You may have been joking but I can't begin to tell you how many times I have seen this as a solution, sometimes it even works but more often it leads to additional problems!
 
I had the same problem. 8 amp fuse blowing. I disconnected the oil temperature switch and held the choke until the engine warmed up. I then put load on the generator and everything ran fine for awhile and then the generator shut down. I was able to restart the generator. The fuse didn't blow. The generator is about 20 years old so I just recently replaced the raw water impeller and I have plenty of water flow. Could it be that because of the good water flow that the engine was cool enough that it shut down to to lack of choke?
 
I had the 8 amp fuse blowing so I disconnected the oil temperature switch and started the generator. The fuse did not blow. The generator would shut down after a time. I replaced the oil temperature switch and the coolant temperature switch problems solved.
 
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