September 2021 - Status Update

 Over 5 years since the last post.   I'm happy to say that in that time the ZR 600 is still going strong - 1500 miles plus on that engine!  Only issue was a hose leak at the oil pump.  I swapped that out, no issue since with the engine.   

But, the chassis, that's another story, all the shocks need a rebuild.  At this point I don't think I am going to do it, we're in the market for a 2-up sled so I think I will either sell ZR outright, or trade it in towards another sled.

Happy New Year! Still waiting on snow to finish the sled up!

January 3rd, and only a dusting of snow on the ground.  So many items to check or adjust on the sled, but I need the snow to do it.........

- The engine needs to be ran for some time to verify the oil pump is feeding fuel to the engine (currently I have a 50:1 mix in the tank)

- Verify that coolant is actually pumping through the rails

- Verify clutch/belt engagement: During my one and only ride since getting the sled together the engine rpms were quite high before the belt engage.  I cleaned the primary and secondary sheaves with a scotch brite pad, and replaced the drive belt.

Where is winter?

December 14th and I was just outside,  6am, in a t-shirt!  Rainy but 61 degrees!  Figures, have the Arctic Cat done and no snow!

Carb motor to efi summary

Brief background: original 1998 Arctic Cat Zr 600 efi motor blew mag side bearings and took lower end with it. Bought a supposedly 98 efi motor from a dealer that only had 1k miles on it. Turns out it was a carb motor. Here is what I had to do to make it work as an efi.

1. Remove impulse line and fitting from crankcase. Replace with plug bolt and washer from dealer.

2. Remove carb boots and replace with throttle body boots.

3. Replace cylinder head with one from efi because an efi motor has a coolant hose that runs from the throttle body to the head, carbs do not.

4. Replace carb stator with efi stator.

That's it, in a nutshell. In my case it helped I still had most of my efi parts needed.

Fuel mix

I should mention that since there was oil pump work performed I mixed up a couple of gallons of 50:1 mix to run on. I'd the oil tank level goes down then I should be good to go after that

First snow, first ride!

We were fortunate here in mid-michigan to get about 8 inches of snow on Saturday.  I was even more fortunate to take the ZR out for a ride!  It ran great, from low speed to almost full throttle. No engine issues at all. There is a noticeable squeak from the track so I need to check that out, but if that's all that's wrong I'll take it!

Finally, it's running!

Before I get to it running, I will summarize how I cleaned the injectors.  

1.  I set them in a prescription pill bottle filled with injector cleaner.  I put tape around the top so the screens were just below the fluid.

2. Took a 12 volt motorcycle battery, clipped alligator clips to the injector, and briefly cycled each  injector 5 or 6 times

3.  Blew them off. 

The screens were now clean so I assumed the rest was.  

Put the injectors back in the sled, dumped in fresh fuel, primed the pump, then crossed my fingers!

It started after about 10 pulls, then quit.  I pulled it another 4 times, then it started and kept running! YES!.  I shut it off after a minute, waited about 5 minutes, then tried again.  It started on the first pull, and I did the same thing 6 times in a row, starting first pull each time!

So, now, besides waiting for snow, I need to double check all my connections, put the hood back on, double-check all the fluid levels, and give it a test run when I can!

Major progress

A lot has happened since the rusty bolt. The motor is in. All coolant, oil and fuel lines installed. Well, everything is in but the hood.   Primed the fuel pump, but the darn thing wouldn't fire up. I poured a little fuel in each cylinder, and it started on yhe first pull. So, I have a fuel issue.  I pulled the supply line from the fuel rail and was able to confirm that there was fuel there. I pulled the injectors, and could see there was not any fuel passing through them. So obviously the injectors were glogged. Next post will be on cleaning the injectors.

Happy New Year!

2015 and still working on this. Gave up and cut the nut off, then picked up a new one at the hardware store.  Temp has been around 0, so I'm waiting for Temps in the double digits before working on this again.

Rusty Bolt

Still dealing with trying to break the nut free!  I think I'll get a portable torch and apply some heat. Stay tuned.

Exhaust manifold bolt/nut

Finished with the electrical, other than the TSS switch, I'm leaving that disconnected for now.  Next step is to bolt up the exhaust.  But one of the manifold nuts is rusted to the stud,  so I removed the stud and will let it soak in oil for a few days to see if it will loosen up. I'll give the clutch a try next.

Priority project-pellet furnace

I'm tired of the high propane prices do I'm installing a pellet furnace. Back in a few days.

Yet more electrical issues, kind of...

It's been almost a month since I posted, but I have been working on this.   But with the serious lack of snow and the holidays, it has't been a priority.

Once I had the motor bolted in and torqued down, I connected the coolant hoses and the electrical.  With the electrical hooked up I decided to do a quick pull test to verify my connections.  Well, guess what?  That's right, no spark!  I double-checked the connections, made sure my tether was connected, key on and on/off button up.  So, I grabbed my voltmeter and started testing all electronics from the stator up.  All components tested fine, now what?!

Quite a long story made short,  I found more than a few references to disconnecting the yellow wire harness from the stator and testing for spark then.  Supposedly this bypasses ALL handle bar controls.  I did this, still no spark.  Then I remembered! I had a problem with the TSS (Throttle Safety Switch) and had disconnected it before the original motor went.  So, despite what I read about the yellow wire harness bypassing everything on the handle bar, I disconnected the TSS.  SPARK!!  So much for the internet forums. I am ashamed of how long I went before doing this.  That just goes to prove, don't believe everything you read.

I dub thee Frankenmotor

Oil Pump issue behind me, connected, bled and so on.  Torqued all the motor mounts.  Started to connect some of the electrical, and, well, turns out the efi cylinder head I bought off of eBay appears to be from a 2001? EFI.  There is a temp switch in the head instead of the temp sensor, why not?  I have so many different parts in to this I do not know what is what any more.  All I know is the head looks identical, so I am swapping sensor/switches and calling it good.  I had asked around on some sled forums, most said it should work, a few said to check the "squish".  Ugh.  I will check the compression before I start it, and if it is within tolerances I am going with it!

Slight delay due to oil pump.

Another bit of information, turns out that most of the EFIs use a different oil pump than the carbs.   Since my carb motor came with an oil pump on it, I assumed I could use it.  Just to be sure I decided to remove the motor (I can now do this in less than 20 minutes) to check it out.  Lucky for me I had kept my pump from my original motor. Like a dummy I removed the pump from the motor so I could check internal workings.  Not lucky for me is that the two pumps look identical, so much so when things were moved on my work bench I could not tell which was which!  If there is a next time I will tag EVERYTHING.  Anyway, since they look so much a like, external and internal, I am just putting one on, and hope for the best.

Some tips on the motor mounts when installing the engine...

1.  The AC Service manual says to install the lower coolant hose to the water pump before bolting in the motor mounts.  Do it!  The front Mag side mount is in the way.  While it is possible to slip it on afterwards, it would be easier with the mount pushed out of the way.

2. When I put the engine in, I installed the bolts in both front mounts, and the rear mag side mount. Unfortunately the PTO rear bolt hole would not line up.  I had to remove the engine bolts from the front PTO side mount and loose then rest to get it lined up.

3.  Likewise for the bottom bolt of the rear mag side mount, loosen the bolts on all the mounts, and remove the engine bolts from the from mag side mount, to allow alignment for this bolt.

Put the engine in....

After making an emergency run to replace a missing motor mount bolt, and a lot of swearing, the engine is back in the belly! Next  - tighten the bolts, connect the wires, refill the coolant, and so on................................not the best picture of my progress, but you get the idea.

I'm baaaaackkkk!

After a long hiatus from working on this machine I vow to finish it within the next few weeks.  However - when I moved it in to my heated workshop from the main part of my pole barn I noticed a peculiar smell.  Long story short, mice had taken up residence in the air silencer.  No one to blame but myself!  It sat in the same spot for 3 years and the mice lived there undisturbed.  So removed the air silencer, clean it out, and the area behind it.  Took about a week of soapy cleaning, Simple Green and Lysol wipes to get rid of the smell.  Finally I put it back in tonight.  Tomorrow I will but the computer module and related items back in.  Then I can pick up where I left off a few years ago. Stay tuned

Yet another setback

Well, I got past the impulse line...no big deal.   I was then at the point where I wanted to install the engine in the chassis.  So i read through the service manual, step-by-step, and look at the chassis.   Seems that there is one more part that I will need to swap that the carb motors do not share with the efi's, the cylinder head.  The EFI motors have a coolant hose running from the throttle body to the thermostat housing on the cylinder head, and the carbs do not.   So now I have to locate the correct cylinder head.

Impulse Line replaced

I was lucky that one of my local Arctic Cat Dealers had the crankcase plug and gasket in stock, so I went an purchased them for $6.34 total - Thanks Groves!  Since I couldn't locate the torque specs for the plug I tightened it as much as I dared to before I though it would break.