last week. I have had a lot of interruptions, but I finally got the head off the engine. I didn't find any big surprises, the piston was a little scuffed up on the skirt and everything was covered with a lot of stinky black carbon. The scuffed piston is normal for a machine that has been abused and the carbon is a result of all the oil that is being burned.
I think I will just give it a basic top end overhaul: piston, rings, valve seals, head gasket, and hone the cylinder. It should be less than $100 for parts and only a few hours of labour. I still need to investigate why it overheated. I'll check out the electric fan wiring system and temp sensor. I'd be willing to bet it's all working fine and the real problem was that the owner let the kids take the machine out moose hunting. Who knows what teenage boys did to it when they were out in the country?
In the photo you can see my homemade valve spring "tool". It is a piece of 1/2" EMT (electrical conduit) with a cutout on the end. The other end has a block of wood that you can push on. I clamp the head down to the workbench, push on the block of wood with my shoulder, and reach in the cutout on the tubing to remove the spring keepers. There are nice manufactured tools for doing this job, but they all seem to be made for automotive engines and are too big for the small engines that I work on. If anyone knows a good source I'd like to hear about it.
Monday, September 27, 2010
I generally like Polaris products and think that they are put together pretty good. One thing that I think they do foolishly though is the recoil starters. Most manufacturers make a simple cover over the pulley with a open drain hole in the bottom. This keeps most of the crud out and allows any water that gets in to drain out.
Polaris makes a cover that is supposed to be sealed up water tight. It never works out that way and a little water always makes its way in. Without an open drain in the bottom the water stays inside and everything ends up a rusty mess.
That is how I found this one. Everything still worked under the cover, but it was wet and rusty. I had to spend a little extra time cleaning things up before I put it back together.
Sunday, September 26, 2010
This is the same machine that I talked about in a previous post. One of the bolts that holds the clutch pilot bearing support came out and flew around inside the clutch cover. The belt was destroyed and the clutch faces were severally chewed up. I talked to the dealership where the machine was purchased and they agreed to send me the new parts for free. The owner is going to have to cover my labor cost, but at least they got the parts.
When putting the secondary clutch back on you need to tighten the nut to 70 ft lbs. That is an easy amount of torque to achieve with a long wrench, but it is almost impossible to hold the clutch from turning. I made a special tool to hold the clutch. I used an old 1 7/16" end wrench to make a special spanner wrench. I drilled two holes in it and put two short 1/4" bolts through the holes to line up with the holes in the clutch. It may not look pretty but it worked great.
Saturday, September 25, 2010
The truck is a 1985 F150 with a fuel injected 302 V8. It has a lot of miles on it, but overall is in pretty good shape. Recently it seemed to overheat after driving a few miles down the road. They asked to me to take a look at it. I took my boat over to Teller and checked it out. The first thing that I found was a radiator that took 3 gallons to fill up. It was also a couple quarts low on oil.
I topped off the fluids and started it up. It started fine and seemed to run good. Then I noticed the huge clouds of smoke coming out the tail pipe. There also seemed to be a lot of air bubbles coming out of the open radiator cap. Looks like a bad head gasket.
I don't think I'll take this job. There is no garage to put the truck in and the weather is starting to get cold. This is not the kind of job I want to tackle outside. I told Randy he should take 20 gallons of water and a case of oil with him and see if he can make it to Nome. One of the auto repair shops there would be better equipped for this job.
Wednesday, September 22, 2010
Another thing to add to the list of available services from Rudstrom Repair.
Wednesday, September 15, 2010
This machine is a great example of Honda engineering. It is nothing fancy or high performance, but well thought out and durable. The engine is a basic single cylinder four stroke motor with push rod actuated overhead valves. It is air/oil cooled with an electric fan.
This is a standard ATV here in the village. These machines will last forever if you keep oil in them. Unfortunately people seem to have a habit of running them out of oil. The normal engine disaster starts just after someone changes the oil. They either strip the threads on the drain plug and it falls out a few days later or they put the oil filter in backwards.
The stripped threads are definitely operator error, but the upside down oil filter is an engineering mistake by Honda. The filter is a cartridge type with a hole on one end and a spring that pushes on the other end. If it is installed backwards the hole for the oil to flow through is blocked off and the engine does not get any oil. I have seen these problems many times.
The lack of oil typically leads to an overheated piston and cylinder. If you run it long enough like this the piston breaks. The rod and crank have roller bearings, so they normally survive fine. Being a push rod motor, the cam is low in the block and it normally has enough oil to survive.
I'm not sure what is wrong with this particular one yet, it smokes pretty bad out the exhaust, uses a lot of oil, and sounds a little "rattly", but it still runs ok. I'll pull the top off tomorrow and see what it looks like inside.
Tuesday, September 14, 2010
Sunday, September 12, 2010
This weekend one of the teachers here in Brevig asked me if I could help them put some new furniture together. The had assembled most of it, but were stuck on the diaper changing table.
Saturday, September 11, 2010
Wednesday, September 8, 2010
It is a simple thing to fix, 10 bolts to take the cover off and there it is. Unfortunately I did not have a spare belt here and I had to call the dealer in Nome to get a new one.
Monday, September 6, 2010
Saturday, September 4, 2010
Growing up in Minnesota I saw lots of Lund boats, some of them very old. It seemed to me that they could last forever. Up here they tend to wear out in 5 to 10 years. The rivets come loose and they start to leak. I'm not sure why the rivets loosen up, it maybe the hard use and overloading or it might be related to the salt water?
This boat was starting to leak so bad that it was getting a little scary. We pulled the boat up out of the water on some rollers, then filled it up with water to find the leaks. By looking at where the water dripped out we found the problems areas. We found a few loose rivets and one spot where 3 of them in a row were entirely missing.
Once we located the leaks we used the tripod to raise the boat up higher to provide enough access to work on the bottom. Tomorrow we will drill out the rivets and replace them with new POP rivets.
I also made a few adjustments to the throttle linkage and changed a faulty kill switch. When I put the motor back in the tank everything worked good. Now I need some nice weather so I can finish up the boat.
Thursday, September 2, 2010
I was lucky and found a brand new tiller for a 90 Honda on Ebay for only $200. Unfortunately I was not so lucky connecting it to my motor. The bolt holes that it connects with were tapped some kind of odd metric thread. I think that they were made for a Honda specific stud that should have come with the motor from the factory. I searched all over for a bolt to fit it but came up with nothing. Even Mcaster Carr, the worlds greatest hardware store did not carry anything that would fit.
Eventually I decided to drill the holes out and tap them to 7/16-20. This is an odd sized fine thread bolt, but is is the only thing that I could get to fit in the available space. I called the auto parts store in Nome and they amazingly stock fine thread bolts in just the size I needed. I gave them my credit card info so they could charge me $1.85 for the bolts and $12 to ship them out here on the next plane. The bolts made it here in the evening and I rushed out to finish up the project. When I opened up the package I realized they had mistakenly sent me 1/2-20 bolts!
I called them back the next day and explained the slip up, the lady at the parts store apologized and agreed to send me the right ones for free! Unfortunately the weather was bad the planes couldn't fly for a day and a half.
Today the weather cleared, the planes flew, and the correct bolts finally made it.