78 Liquifire rebuild!

[Cdnturboz]

Looks great! How are you prepping the aluminum prior to paint?ie so it doesn’t flake off (Mostly for my own reference if I ever paint a tunnel)

[400brian]

I am mainly just trying to get things really clean ( solvent ). I had my 72 400 professionally painted, and the paint falls off it it gets touched.

I am not using primer, the factory never did. If I was spending big money on the paint, I would be looking a lot harder into your question though.

I rattle canned the tunnel on my 73 X8 with JD Blitz Black over five years ago ( and I ride that ), and it has stayed on great. The Blitz Black is very forgiving being as it low gloss. It matches well if you need to touch up areas.

Eventually I may want to refinish the hood for the 78 LF. That is a different deal as it is fiberglass, and how to paint that seems to be well known. I may or may not paint that myself.

[400brian]

The steering system needed to be put back together. I would have preferred to have left it intact so that I wouldn't have had to do all this, but in the end, I don't think it was right anyway.

After fighting with it for an evening, I ordered a 3' long 5/8" steel rod from McMaster Carr to use as an alignment tool. With this slid into the ski pivot holes on the spindles, the two spindles were now locked together in the straight ahead position.
I installed the spindle arms per the service manual specs. This is to ensure you get the correct geometry. I found that one spline change on the spindle resulted in 1/2" of movement at the tie rod bolt hole in the end of the arm. With the arms on correctly, I found that the tie rod was significantly too short. After getting the adjusters loosened up, I found I had to adjust the tie rod out to its maximum book spec to install it. I then adjusted the drag link so that with the bars straight ahead I could install it into the spindle arm.

With the alignment tool removed, I now turned the bars back and forth to see what I had. Turning right the spindle arm bottoms out on the stops just like it is supposed to. Turning left, the right hand end of the tie rod contacts the side of the pan just before the left hand arm hits the stop. This sled has been hit in the left front corner, and apparently the chassis is slightly tweaked.

I think this is as good as it is going to get. Eventually when I get the skis on it, I'll see how they measure.

[400brian]

The NOS HD brake disc showed up, and is now installed. It came with a very rough coating of grey paint on it, which I removed with a wire wheel and palm sander. The shim that came with it seems to put the K-H caliper where it needs to be.

With that done, it was time to install the gears and chain in the chain case. First of course the gears have to be shimmed so that they line up with each other. Being as I have switched to a 80+ chain case, I was starting from scratch. First, I used the 80+ spacer, which is 1/16" longer than the earlier sleds used. I added the shims the book suggested, then added and subtracted until I was satisfied with the result.

I had cleaned up the gears and chain, blew Brake Kleen into the holes on the ends of the shafts to prepare them for Loctite. After I had the gears and chain installed, but before I put the cap screws and washers on, I decided to try installing the roller tensioner. My suspicions were proved correct, the chain was too tight to allow it. After retreating to the parts book and consulting the crew, it became clear that the easiest path forward would be to swap the 24 and 40 gears that were stock 440 Liquifire, and go with the 21 and 39 gears that came with the 80+ chain case. To use the stock gears I would need to swap the 68 pitch chain for a 70 pitch chain. The crew argued that this would take a little top end off, but make the bottom end more responsive. This will probably work well with how I ride, so in those gears went. The roller tensioner now fit, everything was good until I realized I had neglected to fold the fold-over locks on the jackshaft bearing. So the top gear had to come back off so I could remedy that.

The last thing to do here is to install the cover, and while it has been degreased and cleaned, I am not quite satisfied with it yet.

[400brian]

The chain case cover has been installed on the case. An engine plate has been selected ( note: many of these are cracked at the sharp bend on the flange side ), and the engine has been relocated from the shop to the garage. It was heavier than I remembered.

[400brian]

Getting ready to set the engine into the chassis to check the clutch alignment.

As heavy as the thing is, a little weight reduction seemed like a good idea. Although 78 LFs never had electric start, I have a Hitachi starter installed on it. Don't know where I can install a battery, but I will worry about that later, for now it is coming off. Even with the reduced head nuts, I don't think the starter can be installed with the engine bolted to the plate, so I may rethink the removal.

The NOS Prestolite round plug CDI is coming off. A fresh Hewtech rewound stator and Fireplug CDI will be installed.

The exhaust manifold has been removed for clean up and inspection. Tom Rehberg's 78 CC had an exhaust manifold fail last February, so I will give that a close inspection. Looking into the exhaust ports, things looked pretty good. I did a compression test a week ago, and until proven otherwise, I am calling it a runner.

After a little clean up on the PTO end of the engine, I installed the NOS Comet 102-C. More cleaning is planned, then with another pair of hands, the engine will be set into the chassis.

[400brian]

The engine plate I have bolted into the chassis right now is a Cyclone part. The 77-78 aluminum plates are marked with either an "F" for fan, or a "L" for liquid. By the parts book they have different part numbers. However, after close inspection, I have yet to figure out how they are different.
The problem with these aluminum plates is that they are often cracked on the side that is flanged, right at the edge of the plate at compound bend. I have been told that you can find NOS plates cracked. I have two "L" plates that probably could be welded, but not by me. I have an "F" plate bolted in right now, and I am going to set the engine on it to see if the clutches align. If they do, I can't think of a reason why it shouldn't work.

The CC engine plates were thicker than the stock 1/4", but I have never seen one.

[400brian]

So I have learned or re-learned a few things in the last few days.

I thought there was a reason I had put the Hitachi starter on the engine rather than a Nippondenso, and quickly found that that the attached solenoid on the ND hits the motor mount. I also discovered that the reason I had cut a notch in the original engine plate was to make room for the nut that holds the starter on the bottom stud.

With the "F" plate bolted into the chassis, we set the engine on, and quickly found that there was no way I was going to get the four bolts threaded up into the engine. I installed the clutch alignment tool to see where the engine needed to be and found it to be around a 1/4" too far inboard. The engine was pulled back out to re-assess.

I am looking for an aluminum welder to address the two liquid cooled engine plates I have right now.

I did get my clutch tools dug out to complete the clutch installation. First the compressor to squeeze it together to expose the hole in the shaft, then the split nut that engages the holes, then the wrench that holds the split nut. Then it is just put the torque wrench on the bolt and pull to 50 ft/lbs.

Update: as of 12/5/25 I now have the engine plates at a local shop to get them repaired.

[400brian]

My grandson was out today, so I put him to work cleaning the fuel tank.

The tank seems to be in decent shape, but the grime is deeply imbedded into the texture of the plastic. I pulled the fuel pick-up line out, it was in surprisingly good condition. Note the JD script on the line, I am assuming it is the OEM line. I feared that the fitting was going to break trying to unscrew it out of the tank, but in the end it let go.

I also test fitted the K&H juice master.

[400brian]

The two engine plates I took to the welder are back. I intend to use the one I had cut the notch in, because I believe I need the notch to allow the starter to fit.

Right now I am preparing the engine for installation. Getting ready to install a fresh Hewtec rewound stator and Fireplug CDI box. I retarded the timing slightly from stock at Hewtec's recommendation.

The starter motor has been polished a bit, and painted.

I worked on cleaning up the two cooling belt pulleys. The belt pulley behind the recoil is often rusty in my experience, while the upper fares a bit better. That held true on this liquid cooled set up. A rough pully is going to be detrimental to belt life, so I spent some time wire brushing, then sanding. I never get them perfect, but I get them much better.

[400brian]

Today job was to finish installing the rewound Hewtec stator, and get the flywheel back on. Once that was done I installed the cleaned up belt pulleys and the starter cup on the flywheel. I checked the alignment of the belt pulleys, they were not perfectly aligned, but Tom Rehberg assured me it was fine, we will test that! The flywheel cover was bolted on, as was the starter motor.

With the plugs out the engine turns over smoothly, so that is good. After searching around the shop for the last week or so, today I finally laid my hands on the recoil starter! It had that 50 year old fuzzy aluminum look, so I had to do something about that. After the dirt was washed off, I ran the palm sander with 400 grit loaded up all over it. Once the oxidation and the worst of the molding imperfections were sanded off, I polished it with a maroon Scotchbrite pad. This gives it a fairly clean satin finish that I can live with. The flywheel cover had gotten the same treatment.

[High Top]

Lookin good Brian, looks heavy too! But sure does look nice when things get polished up after being covered in dirt for so long.

[400brian]

The carb boots looked salvageable, but after I took them off for cleaning, I wound up chucking them. These things HAVE to seal, genuine Mikunis are available, so I just couldn't in good conscience put these back on. Have a new pair coming from New Breed Parts.

Working on getting the Hewtec Fireplug CDI wired in and the intake manifold cleaned up.

And I dug out the water pump cover, washed the crud off it, and did a test fit to make sure I have the hardware on hand. Been a few years since that was in place.

[400brian]

One of the things I do not like on the 76-78 Cyclones and LFs, is the placement of the fuel pump. In the early versions, the pump is bolted to the engine plate, and then later bolted to bosses cast into the underside of the intake manifold. In both cases the pump is hard to access, to the point of wondering if it would be easier to pull the engine to gain access? When I built my wife's 76 Cyclone a few years ago, I looked closely at relocating the pump to a more easily accessed location. In that situation I resolved the situation by reversing the direction of the bolts, and essentially making them into studs to mount the pump on. I thought that helped at least slightly.

On the 78 LF, I considered the limited options, and in the end decided to try this. There is an open area on the frame ahead of the radiator, this seemed like an area that could accommodate the pump, what I was concerned by was the proximity to the muffler.

I don't have a lot of aluminum sheet or angle lying around, so I dug into the parts pile of a couple of Cyclones that have been parted out. I pulled out a muffler support, and a belt guard bracket. The muffler support was the most robust part, but after cleaning it up I discovered it was cracked, so that got tossed. I straightened the bends of the part slightly and trimmed it to fit the area a bit. I decided to mount the pump on tube stand offs, and I re-clocked the bottom plate with the pulse fitting 180 degrees to make it point in a better direction.

I still had an issue with the fuel supply line and a mounting bolt needing to occupy the same spot, so I offset the bolt to avoid that. I added the same foil backed insulation to the back side of the bracket that I have used on my mid-mount firewalls for years. I tried to anticipate all the things that might interfere with this installation, as the sled gets assembled I will find out how well I did. My concerns about heat issues won't get addressed until I can run the sled.

This is an experiment.

[400brian]

I procrastinated as long as I could. I drilled the holes for the bar warmer and tether switches some time ago, but had never cut the openings in the plastic dash panel. I finally scribed the openings in the plastic from the back, using a compass I found the center of the circles, then carefully drilled the openings with a step drill. Nailed it!

The belt guard had that 50 year old aluminum look, so after degreasing and washing it, I started rubbing on it. There was some corrosion pitting on the top side along with some scratches that were too deep to polish out, but it did turn out shiny enough to show finger prints quite well! I had robbed the belt clip that was on it for the wife's Cyclone a couple of years ago, so a new one from New Breed was added.

I finished the day by cleaning the coolant hoses that will be going back on the sled. It also occurred to me that I have likely never removed the cap from the coolant tank on the top of the engine. I tried by hand, with a pair of channel locks, then moved up to a pipe wrench. Success was achieved finally, clean up continues as things were a little crusty.