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Tomos APN4/4L 4/5 Speed Engine Build Timelapse

50 year old engine – restored and upgraded! There are lot of videos on my channel, where you can see it running and dyno tests. Be sure to subscribe so you don’t miss new tests and tuning tips! Anyway, I hope you enjoy!

Unscrew the nut almost to the end and strike with a hammer to knock out the wedge. unscrew three bolts that hold the panel of the ignition remove the wire locker on the nut of the clutch and unscrew the nut remove the transmission pyramid (attention – washers) unfold the tabs from the safety washer and unscrew the nut remove the clutch drum (sometimes a puller is required)

Heat up the block and instal the new outer part of the bearing remove the gearbox and the starter shaft (attention – washers) remove the oil seal and the outer part of the bearing with the puller remove the inner parts of the bearing press in the conrod pin and fit the new connecting rod pressthe inner parts of bearings (be careful – suitable thickness of washers) insert

New oil seals and push them evenly with a press (attention – evenly and not too deeply) replace the remaining oil seals. these are not so sensitive, so they can be pushed in with hands all bearings that are falling out of the block, should be glued (watch out – clean well with solvent) insert the starting shaft (attention – position of the retaining ear) join the blocks

Together ( dont force them or hit them with the hammer ) tighten the screws, crosswise and evenly in two rounds insert the wedge of the drum (clutch), you can also do this before inserting the crankshaft into the block put the drum of the clutch on the crankshaft and retaining washer and tighten the nut soak the seal with oil and install the gearbox cover crosswise and

Evenly, in two rounds, tighten all six screws lubricate the lever shafts and the clutch thrust bearing (pay attention to the sequence and correctly inverted bearing surfaces). tighten the nut slightly. precisely adjusting the clutch is easiest when the engine is already running. screw the ignition plate – three screws (be careful not to pinch the cable) stopper the sump

With the paper. that allows the piston pin lock not fall in the sump and holds the connecting rod in place. insert the piston into the oiled cylinder (watch out – the arrow on the piston faces the exhaust) insert the needle bearing (not necessary if there is a bushing) put the cylinder with the piston and push the piston pin into the connecting rod insert the piston pin

Lock, remove the paper and push the cylinder down installed the head seal (attention – the orientation of the cooling fins) instal the washers and the nuts (attention – position of the two high-nuts) install the side cover (watch – spring for the starter)

Transcribed from video
Tomos APN4/4L 4/5 Speed Engine Build Timelapse By Stealth Tuning