Outboard Motor Trim Pump

This is the hydraulic trim and tilt unit for a 90 hp Honda outboard.  The unit did not work, so I checked the resistence on the electrical leads and found that it was an open circuit (infinate resistance).  The most likely cause of this is stuck or worn brushes in the motor.  In this photo the motor has been removed and is laying on the work bench, the red stuff is hydraulic fluid where the motor mounts.

When I took the motor apart there was a bit of rust and corossion inside.  The brushes appeared to be OK, but one of the springs had rusted away. 

This motor is built with an internal overheat protection.  It is hard to see with all the rust, but there is two round electrical contacts mounted on a bimetal spring.  If the motor overheats the spring will open the contacts and stop the motor. 

The contacts did not work anymore, so I soldered a jumper wire across them.  There will no longer be an over heat control on the motor, but I think that it is unlikely to be needed in our cold climate.  I reinstalled this part and replaced the spring in the brush holder and the motor runs great now.

ATV Wheel Bearing Replacement

Wheel bearing replacement is a common job on ATVs.  This machine is a Yamaha Grizzly, but most machines are put together the same way.

Once you remove the wheel the first step is to remove the large nut that holds the hub on the axle.  On Yamaha machines the nut is locked in place by a small portion bent into a groove on the shaft.  I use an old screwdriver that I have ground down to match the groove to pry this spot out.

The easiest way to remove this nut is with an impact wrench.  If you do not have an impact wrench you need to find some way to keep the hub from turning.  One way to do this is to put a pry bar between the wheel studs.  Be sure to protect the threads on the studs with a short piece of rubber hose if you are going to pry on them.

Once the hub is off the spindle must be removed from the vehicle.  The ball joints (red arrows) and the steering tie rod (green arrow) need to be disconnected.  These are held in place with a nut on the end of a tapered shaft.

Remove the nut and pry or pound the ball joint loose.  If you are going to pound on the threaded end use something soft like a lead hammer to avoid wrecking the threads.  The other tool pictured is a ball joint fork, it is simple pounded in between the parts and the wedge shape drives them apart.

When you have the spindle on the workbench remove the clip that holds the bearing in place.  This one has holes in the ends that make it easier to get out. 

If you look close at these clips you will note that one side has sharp edges and the other side has edges that are rounded over.  (The top clip is sharp side up, bottom clip is round side up, it is more obvious in person than it is in the photo.)  These edges are a result of the way that the clips are stamped out when they are made.  When installing clips like this you should always put the sharp edge facing the direction that the clip is being pushed towards.  The sharp edge makes it less likely to slip.  In the case of these wheel bearings the sharp edge goes up.

To remove the old the old bearing I use a large hammer and a piece of pipe to pound the bearing out from the back side.  I do quite a few of these wheel bearings so I have made up a jig to hold the hub when I pound on it.  Make sure you have something solid to pound on.  I have an old cast iron weight from a tractor (about 75 lbs) that I put on my workbench.  In my old shop in Minnesota I had a large anvil to pound on.  If you don't have an anvil you may want to put your work on the floor.

Before you in install the new bearing you must make sure that the inside of the hub is clean.  Make sure there is no crud at the bottom of the bore or in the groove around the top.  Scrape or wire brush it out.

Heating the hub will cause it to expand and allow the bearing to go in much easier.  I use an electric heat gun, but a torch will also work. 

When installing the new bearing you can only push or pound on the outer race (green arrow).  If you apply any force (especially pounding) to the inner race or seal (red arrow) you will damage the bearing.    If you heated the hub up enough the bearing will drop in with only a few minor taps.

On this job I used a hammer to pound out the old bearing and tap in the new one. It may seem a little crude, but with care it works fine.  A hydraulic press could also be use to remove and install the bearings.  It would give a little more control, but the rules about protecting the inner race still hold true.  You must only push on the outer race.  An old bearing that has had the outside diameter ground down slightly makes a good tool for this job.  It can be used to press the new bearing in place and insure that the force is applied evenly.

Once the new bearing is seated all the way into the bore, install the clip to hold it in place.  Now the hub is ready to go back on the vehicle. 

Broken Shift Lever

The shift lever on an ATV takes a lot of abuse.  They are constantly being kicked and pushed around with your foot.  The most common problem with them is that they work loose and the small splines that connect them to the shift shaft wear out.  That did not happen to this machine, instead the lever simply broke off.

This photos shows me holding the lever in place where it is supposed to be.

This close up tells a little more of the story.  To remove the lever you take out the pinch bolt by the green arrow and the lever slides off the shaft.  It is important that the bolt is removed all the way, there is a groove in the shaft that the bolt passes through.   A few years ago someone was working on this machine and wanted to get the shift lever off for some reason.  They loosened the bolt, but did not remove it all the way, leaving the lever loose but still stuck.  They then got a large crow bar and preyed on the back side of the lever.  Eventually the small C clip that holds the shift shaft into the transmission failed and the whole shaft came loose.

After this happened they called me up to ask if I could fix the shift shaft that was now falling out of the transmission.  To fix it properly would require removing the engine from the machine and splitting the entire engine and transmission open to replace the C clip on the end of the shaft.  This would be a very long and expensive job. 

In order to save myself some time (and the customer a lot of money), I found an easier way.  The shaft was still able to shift the gears inside, but would simple fall out because there was no longer anything to hold it in place.  The red arrow points to my quick and easy solution.  I simply welded an "ear" unto the frame that keeps the shaft from sliding out.  It has worked fine for several years, and this new problem appears to  be unrelated.  This time the lever actually broke off at an original factory weld.

Fixing the lever this time is a rather simple welding job.  The only complication is the limited access to the welding area.  This photo shows one of my welding tricks.  Sometimes you can bend your welding rod to reach around obstructions.  In this case I used a "U" bend in the rod to allow me to weld on the back side of the lever where there is only a couple of inches of space.

Here is the completed job, ready for a few more years of being kicked around.

Honda Foremen

I had Honda Foreman in the shop recently with an oil leak.  The leak was at a faulty seal on the output shaft coming out of the front of the engine.  The red arrow points to the spot where the lip of the seal is distorted.

To replace this seal the front drive shaft needs to be removed.  The drive shaft has splines on each end and "floats" between the engine and front differential.  The mounting bolts for the front differential are removed and this allows the diff to move forward about 2 inches.  Once the differential is moved forward the drive shaft will slide right out. 

Once the drive shaft is out of the way I used a pick to pry the old seal out.  On small seals like this one it is normally easy to pry them out.  Larger seals may be stuck tighter and require a little more work to get out.  I have a couple of examples of this here and here.

Once the old seal is out it is a simple matter to clean the parts up and press the new seal in.  A small seal like this can almost be pressed into place by hand.  It only required a few light taps with a small hammer to seat it.  When driving it in you must make sure that is not bent or distorted. 

Honda Foreman

I have a newer Honda Foreman in the shop today with a shifting problem.  It was hard to change gears, and impossible to get into neutral.  The transmission on this machine, like almost every ATV, is part of the engine.  In order to do any transmission work you need to remove the engine from the frame.  That takes 2 to 3 hours on this machine.

Once I had the engine on the workbench I pulled the side cover off and removed the clutches to expose the shift mechanism. 

 Part of the escapement mechanism that that turns the shift drum was broken.  This machine was sunk under water last winter.  I suspect that this piece broke when someone tried to shift the machine with the crankcase full of ice.  This second photo show the broken part and another used part that I had left over from a Honda 420 rebuild project.  It appears that Honda uses the same shift linkage on the 500 and 420.

This last photo shows the shift mechanism put back together. There are a lot of springs, spacers, and little parts to keep track of.  Now I need a few more hours to put the engine back in the frame and try it out.

C.O.

Honda Foreman

I have a Honda Foreman in the shop.  This is the standard everyday machine here in rural Alaska.

The owner said that it was hard to start and they thought it was not running correctly.  I started it up and noticed right away that the engine was making a terrible rattling sound.

I pulled it in the shop and checked the compression.  As I suspected, the compression was very low. 

As soon as soon as I pulled the valve cover off I could smell the burnt oil.  These engines are air and oil cooled, if they get over heated the oil gets cooked .  This photo shows the "fins" where the oil flows over the top of the head.  The baked on brown crud is a sure sign of overheating.

When I pulled the cylinder off, the piston was scored.  This photo shows my setup for jacking the piston pin out.  The paper towels are there to prevent pieces from dropping into the engine.  Like most of these small engines, the connecting rod is one piece and cannot be removed from the crankshaft. The pin is held in the piston by two circlips, normally when you take the clips out you can push the pin out by hand.  Sometimes it gets stuck and you have to use more force.

It is impossible to swing a hammer in the small area and using a hammer would risk bending the connecting rod.  I have found that a piece of all thread with the appropriate size spacers and washers can be used to "jack" the pin out.  In this case the pin was stuck in the connecting rod because the rod was overheated/ ran without oil.

This last photo shows the cause of all these problems.  This is the oil filter being removed from it's housing.  The filter was put in upside down.  When this happens it blocks off the oil flow to the engine.  I have seen engines damaged this way several times.  Honda did a poor job designing this system and some owners do not pay enough attention when working on their machines.

This engine is going to need a new piston, cylinder, crankshaft/connecting rod, and all the various gaskets.  The parts are around $900 and there is about 12 hours of labor in the job.  Pay attention when you change that oil!

Honda 420 - Complete

The Honda 420 that I have been working on for quite a while now is finished.  I used the parts and pieces from two wrecked engines to make one good one.  One engine had a cracked piston and a faulty transmission, the other one had a good transmission and a bad everything else.  Both engines failed from a lack of oil.

You can see the older posts about it here and here.

The whole project took about 25 hours of labor and $1000 in parts.  It runs great now, like these basic Hondas always do.  Most of the Honda models are not very high performance, but they all run great.

Honda 420

As part of the rebuild on this 420 I am going through the transmission.  The person that I bought the donor engine from mentioned that it slipped out of gear occasionally.  When I inspected the gears I found a few dogs that had the corners wore down.

When you grind the "gears" in a transmission you are not really grinding gears.  The gears are always meshed together, the grinding comes from the shift dogs.  The red arrow in the above photo points to the rounded off corner of one of these dogs.  As you shift the gears slides on the shaft and the dogs engage on matching bumps on the second gear.  You cannot see them, but the yellow arrow points too them.  Rough use can cause the corners to wear down and eventually they will not stay together.

There are a lot of pieces to keep track of inside the transmission.  I put these stands together to help me keep all the gears, spacers, and what not in order as I took them off the shafts.  You can see in this photo that some of the gears have a light coating of rust on them.  Those are the gears that I took from another machine to replace the ones with worn shift dogs.

Like most ATVs and motorcycles the engine and transmission are all one unit.  This photo shows the case just before I put it back together. 

To the left of the green line is the engine stuff, crankshaft and balancer/camshaft.  To the right is the transmission, forward gears, reverse gear, and shift drum.  It all uses the same oil for lubrication and cooling.

Honda 420 Rancher - Update

This is an update on a project that has been in the works for a while.  You can see the start of it here and here.

Basically I am taking two broken machines and making one good one out of the pair.  Back in December I took all the old stuff apart and figured out what new parts I had to order.  I needed a new piston, seals and gaskets, and a few other small items.  My work shop is very small so I only have room for one project at a time.  While I was waiting for the new parts to arrive (normally a couple weeks from one of the places in the lower 48), I put all the old stuff in tubs and put them in my storage shed.

These two tubs have all the parts needed to put together a complete engine. 

It is a little off topic, but I would like to mention how great Rubber Maid brand tubs are.  I use a lot of tubs for storage and transporting things.  They make it easy to store a lot of small parts on shelves, they are relatively waterproof, and they work great for shipping awkward or heavy things through the mail.  Over the years I have used other brands, but they all seem to end up cracking eventually.  Rubber Maid makes  the toughest of the inexpensive consumer type containers. 

Here is everything all spread out.  I hope I can remember how it all goes together.

Honda 420 Rancher - Update

Here is a shot of the engine all apart.  I found a cracked piston and the cylinder was a little scratched up.  I'll have to replace the piston of coarse, but the cylinder can be honed out.  I also found a few wore out shift dawgs in the transmission.  The gears and sliders are rather expensive to replace, but I can salvage those out of the other wrecked engine.  The oil drain plug threads were also stripped out.  I will have to tap them out to a bigger size. 

Honda 420 Rancher

My latest big project in the shop involves these two broke down Honda 420 Ranchers.  The engine in the green machine was another victim of a stripped out oil drain plug.  Normally when they get run without oil the piston fails and the cylinder gets a little scratched up.  This one wrecked everything, the piston, cylinder, crankshaft, and I think the case was even damaged when the broken rod flew around.  The red machine is a donor that I bought for parts.  It has some kind of  transmission problem.  I am hoping to to make one good machine out of the two.

The first step is too pull the engines out and take them apart.  I had some help in the shop today.  He needs a lot of supervision, but he works for cheap.

Here is the engine sitting on the work bench.  The Honda 420 is the same basic layout that Honda has had for years, single cylinder, overhead pushrod actuated valves.  It has now been upgraded with liquid cooling and a basic fuel injection system.  It also has lots of cost saving features like no recoil starter.  Like most ATVs, the engine and transmission share one common case and oil supply.

Corroded Wire

I had a Honda ATV in the shop today that had a charging problem.  It took a while, but I eventually tracked it down to a corroded wire going to the voltage regulator. 

ATVs around here operate in a salt water environment and it leads to a lot of corrosion problems.  The voltage regulator on this machine is mounted under the rear fender near the tire.  It routinely gets sprayed with water and mud  in this location.  It appears that the insulation on the wire was cracked where the wire bent sharply going into the plug.  The cracked insulation let the salt water get in and corrode the wire.

It was a simple job to fix.  I trimmed out the bad section of wire and soldered in a new piece.  When finished I made sure to seal it up well.  I like to wrap connections like this with electrical tape and coat them with "Liquid Electric Tape."  In this case I was out of the Liquid Tape so I used tape a coating of RTV silicone.  Adhesive shrink tubing also works well, but you must have the type with adhesive inside.  The cheaper kind without the adhesive does not work as well.

Frozen Honda Foreman

Today I have a newer Honda Foreman in the shop.  It went through the ice and spent a bit of time upside down and submerged in salt water.    The driver was cold and wet, but she is ok.

The top of the engine was full of water.  I pulled the spark plug and the water ran out of the cylinder.  I had to remove the exhaust to get the water out of the lower bends in the pipe and the muffler.  The throttle, choke and brake cables were also frozen.  The rear drum brake (that never works anyway on these things anyway) was filled up. The gas tank and the carb also needed to be cleaned out.  Somehow the oil in the crankcase and the front and rear differentials did not have any water. 

For most of the mechanical system being submerged is not a problem.  The real problem is the electrical system.  The machine was sunk in salt water, which is very corrosive.  Once that salt gets into the connectors there is no way to get it out.  It does not cause immediate problems, but I am expecting that this machine is going to have a lot of faulty corroded electrical connections in the years to come.  The salt can also be a problem in carburetors.  The salt deposits block up the jets and small passages and they cannot be dissolved, they must be scrapped or picked out.  Sometimes it is impossible to get rid of it all and the jets must be replaced.

Honda Foreman

The basic Honda Foreman is the most popular ATV in rural Alaska.  They are cheap and reliable.  They may not be the best machine for serious work or off road travel, but they are great for around town.  That is where most ATVs spend the majority of their time, going to the store, picking up mail at the post office, etc.  They get used the way most people use a car.

With all those short trips the electric starters get a workout.  The machine that I had in the shop today was about 2 years old and had 4500 miles on it.  The brushes in the starter where wearing out.  They were not completely gone, but every once in a while the starter would not go. 

This is an easy problem to diagnose.  When you push the starter button you can hear the solenoid click, but the motor does not turn.  If you hold the starter button down and tap on the side of the starter the brushes make contact and it runs.  If you tap on the starter and it still does not run, you should check for battery voltage at the positive terminal on the starter.  If there is full voltage the problem is definitely the brushes.

It is a quick and easy job to replace the brushes, about 1/2 hour of work if all goes well.  The only important thing is to make sure you get the rubber and fiber insulating washer on the positive stud assembled correctly.  Beginners sometimes misplace these washers and end up with the stud shorted to the motor case.

Honda Rincon

I finished up the cam shaft job on the Honda Rincon 680.  The total time for the job was 11 hours and there was about $500 in parts. 

I am always amazed at the amount of engineering that Honda puts into their machines.   Just take a look at this photo of the oil drain plug.  Could you have made a more complicated oil plug?  Note that there is a aluminium crush washer and an o-ring on it.  The service manual says that you are supposed to change both of them when you remove it!

Rather than spending all that time designing the worlds most complicated drain plug they should have figured out a better system for the oil filter.  This photo shows a typical Honda oil change.  The filter is a round paper element that goes in that hole in the side of the engine.  When you pull the cover off the oil pours out all over the place and dribbles down onto the foot well.  There is no way to change this filter without making a mess.

At least on this machine they have an element that is the same on both ends.  On some of the Honda ATVs the filter element can mistakenly be put in upside down.  If that happens it restricts all the oil flow to the engine.  I have seen a few wrecked motors from this problem (I didn't put the filter in upside down, I just fixed the engines when someone else did).

Honda Rincon 680

I got back to work on the Honda Rincon that I started on a few weeks ago.

I am installing a new cam shaft in the engine.  The first step is to press the sprocket off the old one.  I do not have a hydraulic press, but with a good setup and a careful hammer you can get it done.  This photo shows the cam supported by a notched plate under the sprocket.  The yellow thing is my "anvil".  It is a large cast iron counter weight off of an old front end loader.  It weighs around 100 pounds and makes a great foundation to pound on.

A few careful swings with a 4 lb hammer and a punch and the sprocket came right off.  Next thing to do is move the bearing to the new shaft and "press" the sprocket on.

Tomorrow I'll install it in the engine and finish the job up.