Wednesday, February 25, 2015

Workshop Wednesday-Echo Service School

 This weeks edition of workshop Wednesday is a bit late. I have been down in Illinois attending an Echo service school. I've been to other brands service schools but this was a first for me with Echo. They seem to have a pretty good program and a very well thought out system for diagnosing problems with their small 2-cycle engines.
 We also took a plant tour. I was surprised to see it wasn't just an assembly line of overseas parts being put together here. They make all their own plastic parts here. They are also starting to make engine cases here too.
 All in all it was a decent mix of classroom theory and hands on training but I was a bit disappointed because I was expecting a class on engine failure analysis and ended up receiving training on troubleshooting techniques. When I got home I told my wife I was a bit pissy about it and also the fact that the brakes went out on my truck tonight. She decided to cheer me up by surprising me with an early birthday present. Last weekend we were at the Harbor Freight store just killing time while our daughter was auditioning at the University of Oshkosh. I stopped to fondle certain tools and I guess my wife was paying attention because she and my daughters picked out something I have had my eye on for a while.

  It's a 10 ton porta-power kit. I've wanted one for a long time but was never able to justify the purchase. It's not a tool I'll use everyday but will be very handy the times that I need it. Thanks to my wife and daughters for a great birthday gift!

Sunday, February 22, 2015

Seal Puller

 The Rat Turd had developed another leak and although it's a rat, I won't tolerate a leaking motorcycle. In this case it was the shift shaft seal. A new seal was still available from Kawasaki, now all I had to do was remove the old seal. Larger seals are easy to remove with a screwdriver or seal puller but small seals can be a challenge.

 I decided to modify a screwdriver into a small seal puller. Oh I'm sure there's a fancy tool in the Snap-On catalog but this works on a budget.

 Just slip the tool under the seal lip and pry. Care must be taken not to scratch the sealing surface of the shaft.

  So big deal. Who gives a crap about a leaky seal? Well I'm writing this to help myself work something out. The cover that goes on this left side of the engine supports that shift shaft. You can kinda see the shiny area on the shaft in the above picture. I don't want to run with the cover. The exposed transmission without the cover looks more mechanical and appealing to me.

 Here is the unpainted exposed transmission.  I needed to make a new support for the shift shaft but didn't want to dink around measuring out and creating a fancy bracket.

 Here you see the new bushing I drilled out to fit over the shift shaft. That raised boss with threaded hole to the left is where the bushing will be supported from. So in true cheap ass greasy shop rag form, I just bolted a slug to the raised boss then laid a piece of tubing on top of those two and welded it all together. Simple and very rat-like.

 This leads me to my next project. I want to add a foot shifter to the hiway peg. I thought about a hand shifter but right now I'm thinking foot. Having recently made a header that moves all the exhaust system to the other side of the bike, I now have plenty of room for this project. I won't go into details as I don't have any idea yet how I am going to do this but I can say that I have a small collection of free lawn mower parts I want to use.


Wednesday, February 18, 2015

Piston Lock

 People bring broken equipment into our shop everyday. Sometimes the equipment just fails. Sometimes it wears out. Other times the owner tries to fix it on his own and creates more problems. We are going to talk about one of those times. Not to belittle the guy that made the mistake. No, he feels bad enough. I just want to put this out there so anyone reading this doesn't make the same mistake.
 Before we get into it I need to post this pic of Al.

 I couldn't believe he let me take this pic so I of course had to post it. Things are slower in the winter and sometimes we have time to be goofy. I want to be clear, Al is NOT the person that made the mistake with the chainsaw.

 Back to our broken saw. The customer wanted to remove the clutch and do some repairs on the oil pump. To remove the clutch you need to prevent the engine from turning over so you can unscrew the clutch from the crankshaft. A popular way of locking the engine is with a piston stop. This could be a special tool, a stopper that replaces the spark plug or even a piece of rope pushed into the cylinder through the spark plug hole.
 Our guy tried something else. There was a note on the repair card about the customer using a skrench (that tool you get with some equipment that is a screwdriver and a spark plug socket in one) to hold the piston. At first I didn't realize what was being said but then it was pointed out that he admitted to putting the screwdriver into the spark plug hole, across the top of the piston and into the exhaust port. I'll try to explain better with this pic.

 Now certainly this will lock the engine. I'm sure he felt pretty good about his repair until he tried to start the engine. What happened?

  This is a look from the exhaust port where the screwdriver was sticking out. You can barely make out the dent on top of the piston.

 Here you can see where the screwdriver crossed the top of the piston. The burr created from the screwdriver jammed in the port and the pressure applied when removing the clutch created a raised edge and then this scoring. Now the piston ring is seized in the groove and can't seal very well to the cylinder. The engine only develops 90 psi compression and that's not enough for the engine to run.
 This saw will get a new piston and cylinder. A costly mistake that you will never make.


Sunday, February 15, 2015

Rat Turd Exhaust

 Last week I told you about my homemade headers. This week I'll follow up with the rest of the exhaust system.

 Here you can see I routed all the head pipes to the right side of the bike. I built a collector and added a piece of 2 1/2" pipe to that.

 I was out of oil and didn't have any in the engine at this point because I had just sealed up an oil pan leak. Too bad because I wanted to hear how annoying this open pipe would have been.

 Here is the fart can I bought from a co-worker that needed the $20 more than I did. I put a rain flapper on top of the 4" outlet. My hanger bracket is mounted from the same hole the stock muffler was bolted to. The bracket is strong and cheesy, just like a rat bike bracket should be.

 Why is it crooked you ask? Well if it were straight there is a good chance the exhaust would blow right up into my helmet. I'm goofy enough breathing clean air, you don't want me on the road all hopped up on rat bike fumes. Another reason the muffler is on an angle is because I wanted it to be perfectly vertical when the bike was on the side stand. I don't "look" at bikes while I ride them, I look at them sitting still. I think it will look better this way.
 I'm not completely thrilled with the rain flapper and may swap it out for a 45 or 90 degree tail pipe facing to the right side. Once I get the bike outside and fired up I'll decide. If the flapper doesn't bounce at idle or make that cool clinking noise then I may just remove it in favor of an elbow.


Wednesday, February 11, 2015

Workshop Wednesday-Leaky Boots part 2

 Last week I talked about the importance of a tightly sealed crankcase and no intake air leaks in a two cycle engine. The saw I was working on had badly damaged intake boots. Imagine my dismay when I replaced the boots and the saw still ran like it had an air leak.
 Actually, I was pissed off. This happens sometimes. You find a problem that matches the complaint then you fix the problem only to find another problem. Some would say that further tested should have been done before starting the repair. Well here's the deal. Labor rates are high. "Further testing" can add a whole lot to a bill. In order to provide a reasonably priced service to our customers, we sometimes have to "go with our gut" on some of these repairs. I gambled and lost on this one. Sort of like playing poker with Frank and John.
 So now I had to take the time I was hoping to save and pressure test the engine. To do the test I need to seal the intake and exhaust. This meant making a block off plate and seal for the exhaust port. It also meant bolting a piece of rubber between the intake boot and carb. I also had to expose the crank seals. This means removing the flywheel and associated parts on one side and the clutch and cutting parts on the other side.
 So now the ports are all sealed. I removed the spark plug and installed a special adapter that allows me to pump air into the engine. The goal is to pressurized the engine to 7 psi and have it hold that pressure for 1 minute. Spraying a soapy mix around seals and ports will reveal any leaks.

 In this picture you can see bubbles forming between the crankcase halves. The bubbles don't look like much but I couldn't even get one pound of pressure to show on my gauge. This is the worst place to have a leak because it means splitting the cases to repair. In most instances this would make the equipment non-repairable because of cost. In this case it may be worth fixing because a new saw retails for $1100. The customer was quoted $400 for the repair which includes all new gaskets and seals, new crank bearings and the new intake boots previously installed. He's thinking about it.

Lets take a closer look at a Husky 562xp that needs to be pressure tested to satisfy a warranty claim.

We need to remove the starter, flywheel, muffler, bar/chain, clutch, oil pump on some models and the carb.
Muffler removed and plate installed.

Carb removed and plugs/plate installed.

 An adapter is threaded into the spark plug hole. The adapter allows us to hook up a pump with gauge. I pumped this up to 7 psi when I suddenly had an urge to drop a deuce. When I got back several minutes later I took this pic. The engine is sealed tight and didn't lose any pressure (unlike what just happened in the bathroom). If it was leaking I would have used a soapy mix sprayed on all sealing areas and looked for bubbles. Our gauge lets us apply a vacuum to the engine also. This test is mainly for the crank seals which can sometimes only leak in one direction. I pumped the gauge to 5 in Hg vacuum and let it sit for 4 minutes with no drop of the needle. There are no sealing issues with this engine.
 So there you have it. If this looks like something you want to do on your own then I recommend buying the Mity Vac mv8500 like I've used here. It comes in a hard case along with some plugs and adapters. This tool also works great for bleeding motorcycle clutch and brake systems and that has earned it the Greasy Shop Rag stamp of approval.

Sunday, February 8, 2015

Homemade Headers

 I've been slacking off, not holding up my end of the deal. If you come here to read about homegrown low budget bike repair then you've been disappointed lately. Sundays edition is meant to be about bike repair but this winter it's been full of filler. Posts that are mildly amusing and designed to just keep this blog rolling until I get off my ass and do some actual work on the bikes.
 Friday I had some time to explore reworking the exhaust system on the Rat Turd. My searches on craigslist for a used header had turned up empty. It seems there are a lot of used headers out there but they were all "just sold".
A new header is still available for this 31 year old bike and they aren't very expensive. I could have one shipped to my door in 2 days. That's not gonna happen. Rats don't get new headers. If it's a part I can't make on my own then I'll buy it but if it's just a matter of bending, cutting, grinding and welding some steel then It gets done here in my lair. The problem I had is that no matter how much beer I drank I just couldn't piece it together in my head. This is what the stock exhaust looked like.

 I went to bed that night thinking about how to make this a 4 into 1 exhaust with parts I had and how to route it without blocking the oil filter and drain plug. When I woke up I had and idea I wanted to try. Sure enough everything just started to click.

 I cut off all the head pipes and lined them up side by side then tacked them together. This is what they looked like under the bike:

 Next I would need to build a collector. After a little head scratching I decided to rip a piece of tube length wise and hammer the two halves into something that would form the outer sides of the collector.

 After adding a couple flat plates to the top and bottom I welded everything together. I left a 2 1/2" opening for a pipe that will run to the muffler.

 Here is the finished header. It turned out ok and should carry the "rat bike" theme. It looks like it may even flow better than the stock pipes. Vroom vroom!

  So there you have it. Stay tuned for updates on the rest of the exhaust system.

Wednesday, February 4, 2015

Workshop Wednesday-Leaky Boots

 No I'm not talking about wet feet.

 Whenever a piece of equipment comes through with a complaint about erratic idle, the problem can usually be connected to an air leak. Hard starting issues can also be attributed to air leaks. Some leaks are very small and hard to detect. Others are more obvious. This saw looks pretty normal at first glance.

Upon further investigation we find this:

 This intake boot is pulled away from the manifold adapter. This will cause a lean condition and also allow dirt into the engine.
 This repair is pretty simple and not too expensive. The problem is that we don't know how long it ran this way and how much dirt was ingested. It should be noted that these air leaks can also occur at the crank seals and the cylinder base gasket. It's also not often a leak is this big and obvious. Usually a leak big enough to effect engine performance is visually undetectable.
 The lesson to be learned here is that if you have a small two cycle engine that develops a high or erratic idle or is boggy and low on power don't continue running it. Besides possible dirt ingestion, the lean condition can eventually cook the engine and ruin it.
 Why am I posting this? Why not. It's a big part of what I see when working on saws. If you can understand the importance of a tightly sealed crankcase in a two cycle engine then you can become a better fix-it dude. And when it comes down to it, isn't that all we really want?


Sunday, February 1, 2015

Blank Slate

 What's up? My wife is gone on a ten day cruise so I've been keeping busy in the shop, right? Sadly, no. Kegger party every night...not. Instead, yesterday I drove down to Madison to visit my daughter. We had a nice visit but a bit too short.

 I've also been doing some online training in preparation for an upcoming service school. I've been to a few Husqvarna service schools and I'm familiar with their line but this is an Echo/Shindaiwa school. I just want to make sure I have a clue about their engines before I go to a school called "Advanced Troubleshooting and Failure Analysis".  Ya they all work pretty much the same way but I am picking up a few quirks specific to their line.

 I have been giving a lot of thought to a new fuel tank for the Rat Turd. I know I've brought this up before but I think I may scrap any previous ideas and go a different route. The tractor grill idea is starting to bore me.

 So what I have here is a blank slate. I want to build a tank from scratch. A lot of ideas have been sloshing around between my ears. Some include multiple cylinders and chambers. Others are just weird shapes. One idea even includes a mix of steam punk and barbed wire. Odds are the end result will be a combination of all of these. I'll collect potential building materials for a while until one day it just happens. It's nice not being under the pressure of a schedule.

I woke up this morning to a picture message from my wife:

 It looks warm and I know she is enjoying it. I looked out my window and saw a fresh blanket of snow. It looks like about 3-4". I'll be enjoying it later when it stops and I go out plowing. That means I may miss some of the big game today. No biggie. I'm not cheering for either team. I'm just in it for the commercials this year.