80' Liquifire Resto

[idMXLT]

The Trailfire LX resurrection (http://www.jdsleds.com/community/viewto ... 37&t=16732) is coming to a close, so I have begun to focus my attentions on other John Deere related matters. In particular…..

The Liquifire

I know, I know. There are thousands of 80’ Liquifires out there, and they really aren’t that special. If fact, some would say they suck as released from the factory. Even so, I am excited to get this thing back on the snow, and once the carb/clutch/gearing calibrations are sorted out she might be fast to boot!

As per usual,

Resto Roadmap:
-Pull engine
-Find replacement throttle block and airbox
-Clean up engine compartment, assess paint/anti-corrosion needs
-Correct steering slop
-Pull/dry seat
-Pull/clean fuel tank
-Teardown/reseal engine
-Inspect/clean clutches
-Pull/paint/lube ski's & steering gear
-Pull/paint lube skid
-Reassemble
-New fuel/oil lines
-Feel the bog
-Re-gear/re-clutch
-Evade ticket because the Ranger “Can’t believe an old sled would go that fast”

Sled History: Not much, apparently this sled did not work well for the last owner so it didn’t get run much. Liquifire + small yard = crappy riding. Last state reg was 96'.







This thing is a mess!

[idMXLT]

To begin this type of project I like to clean the carbs up, connect a temporary fuel tank, and run the engine for a few minutes. It gives me time to evaluate how it’s running, look for coolant leaks, etc. It also gives me the chance to record what jets are installed and the clutch engagement speed.

The carbs on this sled were fairly clean; someone must have stabilized the fuel. No varnish! It looks like the jetting was updated at some point as well.
Both sides were:

Power Jet: 80
Main Jet: 120
Pilot Jet: 40
Needle Jet: P-4 (159 style)
Cutaway: 3.5
Needle: Forgot to check, will do tonight

Both the main and power jets are pretty lean according to the Fine Tune Manual. I’ll order and install the recommended jets before she hits the snow. Also of interest, the float tangs on both carbs were bent waaay down, lowering the fuel level in the bowls. Someone has done some tinkering! I reset the float height to the level recommend in the service manual.


The sled runs great! Super stoked. Time to tear it apart.


As I prepared to pull the clutch, I noticed that the puller threads in the end of the clutch were stripped…. . Not a good sight!



After some judicious thread chasing, and modification of my puller to improve thread area I got the clutch off. Major pucker moment there, can’t do much on these JD’s without removing the clutch! At this point I noticed…


It was an Arctic Cat clutch! Even more past tinkering…. Not sure which Cat it came from, but an El Tigre might be a likely donor. I am debating whether or not to use this clutch. My biggest worry is stripping out the puller section entirely at some point in the future.

It seems like a previous owner invested some time trying to dial this thing in. I’m going to pull the chaincase cover next and see what gearing is in there.

[idMXLT]

The engine is out. I have some serious cleaning up to do. Every nook and cranny of this sled is packed with cedar needles and spiders. All part of the glamour that is vintage snowmobile reseotration!






Next up is the engine teardown and evaluation. What secrets does this dirty beast hold within? Stay tuned and find out.




I'm considering leaving the heads and cylinders together and removing them as a unit. This will hopefully avoid the head sealing issues encountered by others. Any thoughts on this practice?

[idMXLT]

So I pulled the chaincase cover, looks like I have the factory 22/35 gears. I will likely need to change this given the mountain riding we do, but I'll run it first to be sure.


I also got started on the engine teardown. It actually had oil in the gearcase, woo!






Bit of a whoops...



But corrected it



Found a crack in the engine mounting plate. I'll TIG this up.



I tested the oil pump by spinning it with a drill. I was concerned that it might not function, since the oil injection was disabled. Seems like it works fine! Delivery volume varies with arm position, and it pumps out of all 3 discharge ports.

[nick80lf]

I'd be very cautious with that pump. I have one that will pass the test in the tech manual but doesn't seem to pump enough oil when riding. The tech manual has you measure the output with the banjo check valves disconnected. I think in my case the pump doesn't pump with the added back pressure of the banjo check valves, but I haven't got to that project yet.

I guess what I'm saying is I'm not very confident in the test in the tech manual. My opinion is run premix until you're sure the pump using the correct amount of oil.

Sent from my Motorola RAZR MAXX using Tapatalk

[sledhead16]

We are currently endeavoring in the same project! but I have to do x3 so your lucky! But your post is more impressive with all the pics!

[chriszildjian17]

Are you doing a stock restoration or Adding some custom touches?? I just pick up one these my self. Looking foward to seeing your build.

[sledhead16]

Just stock resto, no trailer queen just good clean trail worthy

[idMXLT]

I'd be very cautious with that pump. I have one that will pass the test in the tech manual but doesn't seem to pump enough oil when riding. The tech manual has you measure the output with the banjo check valves disconnected. I think in my case the pump doesn't pump with the added back pressure of the banjo check valves, but I haven't got to that project yet.

I guess what I'm saying is I'm not very confident in the test in the tech manual. My opinion is run premix until you're sure the pump using the correct amount of oil.

Sent from my Motorola RAZR MAXX using Tapatalk

Thanks very much for this bit of info. I am usually paranoid after any oil injection work and run premix for awhile, but I will see about testing the pump with the delivery valves installed as well.

We are currently endeavoring in the same project! but I have to do x3 so your lucky! But your post is more impressive with all the pics!

Ha, 3 times as much fun later on though!

Are you doing a stock restoration or Adding some custom touches?? I just pick up one these my self. Looking foward to seeing your build.

Mostly stock for me, correcting the usual 80' LF issues (jetting, gearing, clutching, steering column, etc.). I think I'll steal some of Rainville's suspension ideas as well. My formula is typically clean 'em up, make them reliable, and ride 'em hard!

[idMXLT]

One more piece of the puzzle acquired! I scored a Liquifire airbox off eBay, so now I don’t have to engineer a solution for that problem.
The next hurdle is the steering shaft. The lower bearing is wallowed out, and the welded construction of the shaft is making it difficult to machine and fit a bushing.

Any ideas? Find a later shaft?