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Training the hand and mind since 1982.

Wednesday, February 20, 2013

Oh No! Generator problem

During the last storm NEMO, my generator quit the 3rd day without power at 2am in the morning. The generator ran fine for about 20 hours and I fired it up around 1am Sunday morning and ran fine for an hour then died, it sounded like I ran out of gas at first. So I checked the gas, it was okay 3/4 of a tank. Decided to check for a spark, so I took the spark plug out and found there was a heavy carbon on the plug. I figured that was it and I check for a spark, spark was good. Put the plug back in and tried again, nothing....

So thinking back to when I was in automotive exploratory, what makes an engine go? Air, Fuel and Spark. Definitely had fuel that tank was full and the smell of gas was coming out the muffler. Air, checked the filter no blockage, Spark was okay, got zapped by accident, scared the crap out of my wife, lol. Decided to give a compression test with my meter, found 0 PSI, oh sh!*.  Tested the mower next to me to see if the meter was bad, nope worked okay.

Off to big box store for a new generator that morning, luckily they just got a shipment in of 200 in a truck, I was second in line when the door opened.

 New generator PowerStroke 5000 (China)

I had no idea what I was buying, all that was known was it was 5000 Watt. Come to find out after working on it, change the oil after the first 20 hours! It was a really good generator, the engine was a Honda GX390 clone and exact copy. It uses 10w-30 oil very common unlike my old generator. Got the GX390 parts manual online and the service manual online. I would recommend an additional 1 foot of 1/4 inch fuel line to making draining the tank easier. Also you need a L14-20 Plug if your using the 240V line, my old generator was different plug (another story). Runs really good with a one pull start, very well build, heavy duty frame.

A week later I decide to take a look at the old generator, from what I gather it was a Briggs and Stratton Intek OHV 18HP Model 204400. After finding a couple of youtube video online they are notorious for head gasket leaks. In hindsight it did burn oil about 2 oz every 4 hours of operation. After opening the OHV I found a thrown push rod, I guess what happened it the oil got low and pushed the rod out There is no guide or anything to hold the rod in-place except the cam and the rocker. I also found the intake valvle way out of spec a .04 inch gap (should have been .004). So I inspected the rod and down into the cam, looked okay so put the rod back in and adjusted the valves. Put it back together and it fired right up! I've ordered a new head gasket and OHV gasket, I will post the tear down and replacement another day.

Thanks to my wife who was out at 2am pulling the starter cord so I could measure the compression, thanks hunny :)