340lc and 440 lc restore and rebuild

[red19lite]

my two year old siberian husky he kinda liked the sound of that zenoah too! made a couple laps of the the house and shop he went nuts ;D

[rupprat]

WOW Thanks so much for your time and trouble. It must have taken almost as much time working on the thread as it did working on the engine. Great job !

[red19lite]

here a neat little coolany recovery tank (keeps green rippers from dripping) it just velcros on you can get one a motorcycle shop motion pro part no11-0025 there about 25 bucks , if you cant find one pm me ican get it for you it has a eight oz bottle with a overflow too its pretty neat

[red19lite]

also added a bleeder for cooling system its a air compressor bleed off cost about 4 dollar at lowes this helps in purging the air out the system

[red19lite]

put a better used seat cover on tonight got the taillight and brake lite up and going catching up on a lot of little issues on this sled did aliittle cleaning its starting to come around

[red19lite]

got the comet 108 alined and center center set ,cleaned up secondary and installed new pucks in it, were out of snow here, but it started snowing little tonight, i need to put some different skis on it and aline them and get a working tach, and fix the speedo needs short drive key and cable, then it will be safe and can start tuning on the clutch and carbs ,

[mrrupp1]

red19lite, Thanks for all the pictures and information. The Xenoahs are my favorite Rupp power plant. It's great to see somebody spend time building one. I have 19 liquid cool Nitro's and one Liquid Magnum. Most of them are in parts or need restored, but five are together and are my main trail sleds. I hope when I'm ready to build a fresh motor I can call you and pick your brain. Thanks Clint

[gruppski55]

very interesting red19lite wish i had all your engine rebuild knowledge great job gary GO RUPP

[red19lite]

mrrupp1 thats a whole lot of zenoah you got, ask anything, if i can tell what i know of it i will, no big secerts here just want to see you suceed with your xenoahs, 20 engines thats alot bearings, gaskets,seals and pistons ,guruppski55 now you have some of my engine building knowledge maybe your the next to take this xenoah thing a bit farther, all comments thank you , if any of you guys have a xenoah trick you want to share you should start a thread on them, the only dumb question youll ask is the one you dont ask , these things havent been built since 1978 but they keep on keeping on. some of the recent sucesses of these engines are just guys not giving up on them i knew they were a winner all the time later kevin

[nitroenforcement]

That is a fantastic rebuild you have done. Outstanding!!!! Are you possibly going to be showing it this year at Waconia?

[red19lite]

here a little deal i been playing with gas guage fot 76-78 nitro and mag, you drill the cap out in the center to 1.250 and get some simplicity zero turn gas guage parts,

[red19lite]

the parts no.s for the simpicity parts are 5023197sm for the guage and 5022917x1sm grommet, the nice thing about it is the guage can be turned to the position you want in the cap if you dont have a simplicity deaLer near you ican get you the parts there 25.00 just pm me if you like

[motoclimber]

All of the work you have done is AWESOME!! It has been a pleasure reading up on everything. GO RUPP

[red19lite]

there seems to be alot of confusion on 76 verses 77-78 440 xenoah pistons on the left are three 76 samples oem and two wiseco 2264 series one with cs type ring one with L ring, there was also a 2283 that had thin tool steel rail ring, i will atemp to tell you the differences between 76and 77-78 all 76 piston have the ring pinned in the center of the piston on the intake side ,oem 76 piston have cast pin boss with a .877 width, some wiseco 2264 have a cast pin boss at .908 uses stock 76 thrust washers that are .136 thick, some 2264 have milled pin bosses ranging from 1.006 to 1.031 and were supplied thrust washer with the piston from wiseco thickness wasfrom .195 to .211 the wiseco stuff was all over the place

[red19lite]

here a pic of 76 pistons showing different pin boss widths

[red19lite]

here a pic of 76 on right and 77 on left connectting rods , 76 rod is narrower but has a 25mm bore for the bearing on top the bearing size is 20mmx25mmx19mm wide the bottom pin is 22mm and the bearing bore on the bottom end is 32mm, the 77-78 rod on the left is wider and uses a 20x24x22mm wide bearing on the top, the bottom pin is 25mm and bearing bore is 35mm, the only thing thats the same between 76 and 77-78 is 20mm wirst pin diameter ,

[red19lite]

here another pic of rod 76 on left 77-78 on right

[red19lite]

here some widths on rod thrust washers combinations on 76 rods left is stock oem ,left is for wiseco or 77-78 oem piston to 76 rod with the large pin boss 1.004

[red19lite]

heres some 77-78 piston two on lfet are wiseco one on far left is a 2281 and has the tool steel rail ring the middlle is a 2269 with cs type ring the one on the right is a oem xenoah piston, all 77-78 piston have the ring end gap offset from the center of the piston becuase of different port layout. dont use 77 pistons in 76 clyinders the piston ring will eventally break in the transfer ports, 76 pistons are tobe used in 76 cylinders only also,

[red19lite]

all 77 -78 pistons have 1.004 pin bosses some of the wiseco run wider, you can run 77-78 pistons and cylinders on a 76 bottom end use the .195 thick thrust washers, you also can run 76 pistons and clyinders on a 77-78 bottom end if you use the wisecos with the wider pin boss 1.004 + you can use the stock 77-78 thrust washers .136 thick the oem and early wiseco pistons coulbe used if the pin bosses are milled out farther , i you didnt the thrust washers would be to thin to hold up very long, the 77 crank is long on the mag end because of the extra bearing on that end the water pump bracket is also wider on the 77-78 everthing else interchanges if you putting a 77-78 crank and cases on a 76