1979 Trailfire Problems

[xcr800]

How hard is it to change the seals? And is there a how to on how to replace the seals

[Rodimus Prime]

Remove clutch and recoil, remove 4 bolts holding engine mount in place remove engine from sled, Remove engine mount, remove flywheel, remove fan housing, remove stator, remove all bolts from bottom of engine case, tap with dead blow hammer or rubber mallet to split bottom of case, remove ribbed seals, clean seal area throughly with cleaner and sand paper, get replacement ribbed seals ( there is a groove in that case if you dont use ribbed seals they jsut spit them out) take scotch pad to outer edge of seal to remove teflon packing material, use threebond 1104 sealant sparely to outer edge of seal ( this helps because most cases are now pitted on bottom edge.) put grease on inside lip of seal ( this prevents premature seal damage when installing) its best to clean and polish area of crank where seal sits, install seals while still tacky, make sure both mating surfaces of case are clean and free of any previous sealant.. put more 1104 sealant on case mating surfaces, put bottom case on engine, press down by hand, bolts should have clean threads if not wire wheel threads put a dab of oil on threads to prevent sticking, DO NOT PUT LOCKTIGHT, bolts should have a 1/2 lock washer and flat washer replace the washers if damaged or compressed, flat washer have a natural concave to them the concave should face engine. install all bottom bolts turn in so that they just touch case, Make sure new seals are correctly seated and not offkilter ( common cause of premature failure ) torgue bolts down in increaments and follow torgueing pattern available in most generic manuals, retorgue again after you have finished, at this point you can throw a dab of locktight on outside of bolts if you feel the need, put engine componets back onto engine, make sure the stator plate mark is aligned to split of crankcase. reinstall engine into sled, whole process sounds difficult but is actually really easy takes about 4 hrs total.

The reason you dont put locktight on threads into an aluminum case is that there is a very good chance that should you have to remove bolts again they will most likely remove the threads as well ( seen way to many of these cases) the locktight will hold a bolt just as well on outside of bolt as on threads. There is other brands of snowmobiles where you have little choice but to use locktight as they dont have lock washers or even flat washers however most of these machines also have usually a variety of oversized bolts after a couple years as well.

If you get the chance you can look up the history of locktight its rather a good read.

Something i prefer to use on snowmobiles is an inch pound 3/8 drive torgue wrench as the scale allows for greater accuracty and all you have to do is multiply the ft pd measurement by 12. Dial torgue wrenchs are good so are plain needle ones, the snap it type can be a little frustrating as they wont always snap at the right torgue, they are supposed too but after checking with another torque wrench i have found that even brand new snap on wrenches one in seven are torgued a ft pound or two over while others are under, On bigger engines this is within tolerances. on small engines,,,well a pound or two can make a big difference.

[smitfire]

Where are you at?? get this done??