78 Liquifire rebuild!

[400brian]

The spindles are free!

The spindle with the frozen in bushing and bolt got some attention today. I drilled a slightly larger than 3/8" hole down the center so I could install my puller. I warmed the tube up with the acetylene torch, cranked the puller up tight, warmed it up again, and finally the bushing broke loose.

So by turning the puller nut and tapping on the opposite end, the bushing slowly was removed from the spindle. Once it was out I ran the dingleberry hone through the tube and got the rust cleaned out.

The 78 spindles are a one year only part, and because of that are hard to find. Once these get a final clean-up and a coat of paint, they should be good to go.

[400brian]

Working on the CC suspension today. I had a plastic side idler that was solidly corroded onto its bracket. The wheel was installed with the C-clip against the bracket, which complicated things. After some effort I was able to pry the clip out and tap the wheel off the bearing. After that the bearing was introduced to the torch, cutting the outer race, and then the inner. I ran the dingleberry hone through the tubes of the suspension arms, getting things cleaned up a bit.

I have been working to acquire parts and hardware to re-assemble the suspension. Today I was examining the one auxiliary idler assembly that came on the skid. As near as I can tell, this assembly is interchangeable with the same idler setup on an 80 Liquifire skid. I happen to have one on hand, so I removed the assembly to more closely examine it, and the more I looked at it the weirder it got.

The one that came on the CC skid has the aluminum center wheels, with steel tube locating spacers between and outside of the wheels. One of the outer spacers slid off allowing me to measure the diameter of the shaft. The thing was that the reading made no sense, it wasn't showing numbers that indicated any fractional size. I flipped the switch to metric, and now the reading showed 17mm. The 80 LF assembly came apart completely in seconds, and the wheels on it are of the black plastic variety. I tried sliding one of the black wheels onto the CC shaft, and found the CC shaft too large. Looking at the shaft out of the 80, I saw that it had been turned smaller on the outer 2". Measuring the shaft, I found it was 5/8" and the ends I saw 16mm. I also noted that the steel spacers were the same on both wheel assemblies.

I had no idea what was going on here, so I contacted Tom Rehberg and asked him. He told me that on the CC suspension he did a while back, he found the idler shaft to be 17mm as well, but his was aluminum. Rainville tells me he doesn't remember the 80 aux shaft to have a step in it like mine, so this is a hot mess. 17mm rod seems to be somewhat uncommon and pricey, so I was looking for another option. Tom offered some thoughts on bearings, which gave me an idea.

The two wheels I have here use different bearings of course, because how else could it be? I went to Wahl Racing's website, and quickly found they had the bearings I was looking for, and they had an ID of 5/8".So this should allow me to use the cheaper and more common 5/8" steel shaft.

Note the 1/4" hole at the tip of the rail. Someone drilled a hole for a hyfax retaining bolt, this is not shown in the parts book. Each rail also had the little aluminum hyfax retainer installed at the rear as well.

[400brian]

On the 78 CC suspension; Today I decided to disassemble the auxiliary idler wheel assembly that came on my suspension. Once more I had to bring out the tube and redi-rod puller I use. I threaded the rod into the axle, wound up the nut, and basically pulled the axle out of the wheels.
Once the axle was out, I removed the C-clips and knocked the bearings out of the wheels. The plan is to obtain NTN bearings from Wahl racing, and install the wheels onto a new axle with new tube spacers.
The entire suspension will get new shafts throughout, and I need to build another complete auxiliary idler assembly to replace the one that is missing.

[400brian]

Mocking up the rear axle. At least 2 of the wheels need to have the bearings replaced, as we have found the ones I put in these were sub-standard.
The aluminum axle will be replaced with a new steel one, and a couple of new shim washers need to be found.

The aluminum teardrop spacers between the idlers are the dead giveaway of a CC suspension. The square steel spacer between the bracket and the outer wheel are just as unique, they just don't jump out at you.

[Cdnturboz]

Looks great

[SS440-80]

Good job man!

And coming from a millimeter land, I must say that no shaft or screw/bolt or nothing use 17mm... Only the heads on M12 bolts use a 17mm wrench.

[400brian]

A teaser for a side project I am playing with.

[400brian]

The clutch that came on the 78 LF was liberated to replace the Salsbury on my 73 X8 restoration a number of years ago. I did that because I knew I had the parts to put together a brand new clutch. Many years ago, back when there was a regular supply of NOS parts showing up on ebay, I bought a Comet 102C fixed and moveable from a guy here in Wisconsin. That was the starting point, I then bought a new spider from Central Snowmobile ( that they actually had in stock ), shortly before Comet sold out to Certified parts and there was a lull in parts availability for a couple of years.

With the 78 on the clock, everything needs to be gotten ready, so I pulled the box out today and took stock of what I had. When I opened the box, I found it was as I remembered it. It is really fun to work on something that doesn't require cleaning first! The first thing I decided to do was locate the "R" arms that I took out of the original clutch. I had seen them recently digging through the parts stash, so I was able to lay my hands on them quickly. In the same box of stuff I found a set of arm pivot bolts, and in another I found the NOS black spring I had acquired in the last year or so. The pivot bolts are an additional expense, but are so much easier to install than the original pins with tiny roll pins.

I gave the lightly used arms a final cleaning, then installed them into the moveable with only one short break to search for a shim washer I managed to drop onto the floor. I did not have an Allen wrench to hold the bolts, so that will come later. The parts book shows one shim washer to be installed under the spider, so I found one of those. The spider has to be installed with Loctite and torqued to 250 ft/lbs I think, so I will wait on that until I am absolutely sure I am ready.

At that point it appeared all I needed to finish up this clutch was a new cover. I have never had a new cover, but it seemed that if I was going to call this a new clutch I was going to have to get one. This clutch is new enough that it uses 1/4" x 1 3/4" bolts to hold the cover on, and there was a bag of them in the box with the clutch, so I was good to go there. I got on the computer in search of a new cover, found that they were $56 or more, but it didn't matter as Dennis Kirk and MFG Supply were sold out. I eventually found a place in NY that had one for $25 and shipping, so that is the direction I went.

This is the closest thing to a brand new clutch I have ever had! I think I have less in it than buying a new one, but probably only about $100 less.

[400brian]

On the 78 LF CC suspension project; Beside refurbishing the mutt of a suspension I have, I need to make it match an available track. The original CC used a Yokahama all rubber track that matched the Deere rail width. It was a 2.52 pitch with 3 rows of drivers. The track that is being used nowadays, is also obsolete, but was made in far greater numbers. It is a Yokahama 16" track used in Arctic models.

The biggest issue with this track is that the windows are slightly closer together. The drive lug layout matches Deere's drive shaft and rear idler distances very well. You can run this track without modifications, but there are a couple of issues. The stock Deere rail width will have the hyfax running very close to the drive lugs. These tracks have clips with a side that goes up and over the lug, installed every other one to control side thrust. Those clips tend to contact the lugs on the drivers, wearing into them in short order. The track Deere used had a clip that had a thrust surface to the inside of the rails.

Here I have swapped around some washers on the rear arm, and cut 1/4" off the center and front shafts. This has the rail width fitting the track much better. The front suspension arm will have to be modified, and the rear idler spacers will have to be modified to match the new rail width. The side idlers will have to be spaced out a bit as well. I am cautiously optimistic this will work.

[400brian]

After narrowing the 78 CC suspension a quarter of an inch to better fit the Arctic Cat all rubber track I plan to use, the next task was to make the front suspension arm fit and work.
There was just enough tube sticking out beyond the arms that I could cut ⅛” off each side. The hacksaw made short work of that, and while the measuring I had done had me hoping this would bolt in and work without further modification, the proof would be in the pudding.
As I tightened up the thru-bolt, I watched the gap disappear between the arm and the towers until as the nut came up tight it was gone. The arm moved, but not through the whole arc it needed to function.
After thinking about remedies overnight, I came up with two ideas; 1) I could take the angle grinder to the tower and get the clearance I needed, or 2) I could heat the edge of the tower with the torch and bend it outward a bit. I didn’t want to remove a lot of material from the tower, but this would be the simplest solution.
As I really had no idea exactly how much area needed to be removed, I decided to try the torch first. I was going to have to do this quickly, as I had installed the hyfax to accurately determine how well the skid fit in the track windows the day before, and I didn’t want to damage them. I warmed up the area to be bent cherry red, set down the torch and picked up the hammer, and watched the heated area cool before I could tap on it! Between the aluminum rail acting as a heat sink and the 40 mile an hour wind that was blowing, I had a problem. I tried it three times and did get it bent a bit, but I was starting to smell the hyfax, so I stopped. I did the opposite side to about the same degree and then shut the torch off.
I assembled the arm to test the fit, and decided that while progress had been made, I had a way to go yet. The whole area was too hot to touch, so I decided it was time to bring in the grinder. I rounded the edge of the tower where I knew that contact was being made, then again tested the fit. I found progress had been made, and it wasn’t going to require much more to make this work! I worked a couple more areas a bit, and the arm was moving freely in an arc that should be adequate. I was happy that a minimum amount of material had been removed.
The rear axle spacers still need to be reworked, and the rear arm has a slight bend where apparently it bottomed out on the shock, bending the tube about an eighth inch dead center. I can get the shaft into it, but it doesn’t turn freely. Video here:https://www.facebook.com/10002223399475 ... 8907323640

[400brian]

Shortened the aluminum spacers a bit to match the new width of the skid. Will have to toss the suspension in the track and make one last check of the fit. The upper tube of the rear arm has a bit of a bow in it, so it needs to be straightened or replaced yet. When the weather gets a bit warmer I suppose I will have to hit the steel parts with the sandblaster, and get things looking better.

[400brian]

Completed the assembly of the 102C. Tightened the spider on with a bit of red Loctite, that is the Deere tool. I then installed the new cover. The only used parts in the clutch are the lightly used "R" arms.

I finally broke down and bought the Comet "Grunt" tool. It is a hex headed shaft with a drilled 30 mm taper that simulates the crankshaft. Interestingly, the bolt that a /22 Kioritz uses to retain the clutch is too long, it bottoms out in the tool before it gets tight. I found one that would work in the stash, I don't know if it was from a Salsbury clutch or what, but it was a bit shorter and worked.

The service manual has you hold the clutch with a drilled square nut that fits over the end of the clutch shaft, and a bolt goes through the hole in the shaft. I'm not sure the Comet tool was much of an up-grade. Comet says to tighten the spider to 250 ft/lbs. The Service Manual simply tells you to tighten it. I put the breaker bar into the Deere tool and pulled till my eyes bugged out and called it good.

I dropped the rear idler shaft into the track today and found it fit nicely between the drive lugs. That was a serendipitous accident. After i shortened the aluminum spacers to match the new rail width, I simply added two of the same washers I had installed between the spacers and the rail bracket to behind the outer wheels. I figured I most likely would have to buy machine shims to get the outer wheel placement correct, but after looking at it closely, I don't think I could improve on it.

[400brian]

Continuing with the CC suspension.

The shock is the travel limiter for the rear suspension, so I needed a shock to properly mock up the thing. Brock advised me that a 04-252 was the hydraulic version I needed. I also found a thread here on the JD page from August of 2009 where Kenny was asking the same question, and was advised of the same number.

I ordered the shock and some bushings from MFG Supply Sunday night, and they hit my doorstep Tuesday morning. I had no idea if the bushings I ordered would work, they were described as fitting the shock and fit various Cat sleds, PN 04-277. Looking at them they appear to be what I needed. Details to follow.

[400brian]

The shock seems to generally fit. The rubber bushing pops into the shock eye easily enough, but the steel bushing is slightly undersize of the needed 7/16", so they will have to be drilled out just like the shocks we are using on the skis.

I have the option of using a Trailfire rear arm here. The Trailfire arm actually has the shock mount on the top of the tube when installed as did the CC arm, where the 80 LF arm I have here has the shock mount on the front of the tube when installed.

[400brian]

Finished up the assembly of the 04-252 shock for the 78 CC suspension. This shock is 13" open, and 8 7/8" closed. The bushing kit ordered was 04-277. Deere used 7/16" diameter bolts for the shocks, and they did not fit through the steel bushings by the slightest amount. I have drilled the shock eyes out on several sets of the SPI shocks we are using on the skis and stock 78 suspension. You can run metric bolts to get around this issue, but I refuse to do so.

These bushings required the slightest amount of material removed. Holding the bare bushing while drilling was going to be a challenge, but I accepted that challenge. A lathe or even a small vise on the drill press table would have been better, but I decided to shake hands with danger and just hold the bushing with a Vice Grip. What could go wrong?

I knew that with the small amount of material being removed, the chance of the bit grabbing was high, so I proceeded cautiously. After the wrench had been ripped out of my hand 3 times, I oiled the bushing and drill bit with 2-stroke I had in the oil can on the bench. I also got even more careful with the feed rate, and in just a few seconds had the first bushing done.

The second bushing went better. I lubed the bushings with a little detergent, and they slid into the rubber bushing in the shock with just a little bit of persuasion. I will have to make some spacers to keep the shock centered in the arms, and I will probably buy a couple of specific length drilled aircraft bolts with castle nuts to bolt it all together. I blame ideas like that on Jon Carlson, 15 years ago I didn't much worry about stuff falling off.