When putting the crank, bearings. Transmission and all the other parts should you pre oil or grease anything? How do you clean them and the cases? Thanks.
Cleaning bottom end
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The service manual has a decent reassembly guide and actually covers what needs to be lubricated and with what during reassembly.
I can give you a few pointers though: the ball between the two clutch pushrods NEEDS lubrication and the clutch fibers need to be soaked with transmission fluid (whatever type you're going to use).
The output shaft seal (the one behind the front sprocket) needs some heavy grease on it while you're sliding the transmission gear sets into the left side case. The factory service manual recommends installing a small o-ring into the groove on that shaft to keep the seal from "grabbing" the groove but it's been my experience this isn't necessary unless this is a new seal (and you're a gorilla while reassembling!). The old seal is already the correct diameter and only needs a little grease inside of it to allow it to slide right over.
I've always had trouble installing a new crank into a new stator side seal if the seal is pressed in first.... I don't know why that is but it's normal procedure now to pull the crank through a new crank bearing WITHOUT the seal in place, lube the seal and case with fresh 2T oil, and then drive the seal CAREFULLY down into the case. Everytime I try to pull a crank through a new seal, the seal lip grabs the crank and pulls the seal out backwards (no matter how much lube I use).
Liberally dose the rebuilt crank and post sweated crank bearings with 2T oil before reinstallation. You DO NOT want them starting dry, it will reduce their service life. Make sure that the wrist pin gets a good coating of 2T oil before installation of the piston as well. Most people forget that and while it doesn't guarantee immediate destruction... you don't want any sliding surface dry on start up.
I can give you a few pointers though: the ball between the two clutch pushrods NEEDS lubrication and the clutch fibers need to be soaked with transmission fluid (whatever type you're going to use).
The output shaft seal (the one behind the front sprocket) needs some heavy grease on it while you're sliding the transmission gear sets into the left side case. The factory service manual recommends installing a small o-ring into the groove on that shaft to keep the seal from "grabbing" the groove but it's been my experience this isn't necessary unless this is a new seal (and you're a gorilla while reassembling!). The old seal is already the correct diameter and only needs a little grease inside of it to allow it to slide right over.
I've always had trouble installing a new crank into a new stator side seal if the seal is pressed in first.... I don't know why that is but it's normal procedure now to pull the crank through a new crank bearing WITHOUT the seal in place, lube the seal and case with fresh 2T oil, and then drive the seal CAREFULLY down into the case. Everytime I try to pull a crank through a new seal, the seal lip grabs the crank and pulls the seal out backwards (no matter how much lube I use).
Liberally dose the rebuilt crank and post sweated crank bearings with 2T oil before reinstallation. You DO NOT want them starting dry, it will reduce their service life. Make sure that the wrist pin gets a good coating of 2T oil before installation of the piston as well. Most people forget that and while it doesn't guarantee immediate destruction... you don't want any sliding surface dry on start up.
I really don't like to reuse bearings, but some time the wallet doesn't have enough to give so i have used throttle body cleaner and blew it dry with my air compressor until i felt no resistance. I don't know it this is an approved method however. But did work for me
Ok thanks and how do you guys press in the crank bearings? I got new ones do you have to take it to local dealer?
Same way heat with a torch evenly around the bearing ......aluminum expands faster than steel ....they should just fall out
It's a process called "sweating" bearings.
Bearing outer races are made of steel, the case area that holds the bearing in is aluminum.
The coefficient of expansion of aluminum is *ABOUT* 2 times that of steel so heating the cases allows the aluminum to expand to an actual size greater than that of the steel bearing race while the bearing is actually the exact same size (or possibly even larger
) as the case hole at room temperature. This is called a thermal press fit or interference fit and it allows a "no fastener" approach to the bearings. Under normal circumstances, they'll NEVER move because the case is "clamped" down around the outer race but they CAN be removed by heating the cases up to a reasonable temperature. Reasonable being more than operating temperatures will ever reach but less than liquidus temperature. In other words, the bearings won't come out while it's running but can be taken out without melting the case half...
Elvis said propane torch but it's been my experience that a propane torch can only heat the case area around the bearing so effectively as the entire case acts like a very large (and very efficient) heatsink and carries the heat away faster than you add it with a propane torch. It's been my experience that you need more heat and more directed heat. A MAPP gas torch is a readily available type of torch that uses a special fuel in the same basic way that a standard propane "plumbers torch" works except that the fuel burns hotter. The resulting flame focuses the heat on the case area around the bearing race to get it to "that temperature".
Properly heated, a crank bearing will actually simply fall out of the cases.... believe it or not, properly heated, a crank bearing will simply fall right back into the same hole.
I can give you one simple tip and anyone who's done a set of crank bearings (especially those who I've advised!) can tell you the same. There is no "magic" number or amount of time you should heat the cases in order to make sure they're hot enough for the bearing to come out. There is a simple and nearly guarnateed indication that you're there though! Heat around and around the outer bearing race until the light film of transmission fluid in the transmission half of the case begins to smoke. When the transmission fluid is boiling off the cases, the around the bearing is hot enough to flip the cases over and push the bearing out with a socket. If the bearing does not come out easily, flip the case back over and look to make sure it's not "weiner-eyed" in the hole (usually are if they don't just fall out on their own). If it's crooked in the hole, just lightly tap the socket down focusing on the side that's "highest".
When you get ready to install (if you're REAL good, you can remove and reinstall the crank bearing with on heating all at one time), use a pair of work gloves and throw the bearing in the freezer in a plastic baggy overnight. Freezing the bearing isn't necessary, I've installed room temperature bearings many times with NO problem at all but it does shrink that bearing a tiny bit more.... and make sure you drop the bearing in straight while the case is VERY hot (again, boiling transmission fluid is a really good indication!) and then use a hammer handle to KEEP pressure on the bearing. The case will actually try to force the bearing up and out of the hole slightly as it cools so keep pressure on the bearing for 30 seconds (or longer if you're not a particularly lucky fellow).
If you don't get the bearing in straight away the first time, DO NOT beat on the bearing. Re-heat the case allowing the bearing to fall into it (if gravity will do so for you) or the bearing to fall back out and then drop the bearing back in by hand.
And some dude survived falling off the Golden Gate bridge one time. Doesn't mean I'm going to recommend it....
Just 1 case bearing siezing due to lack of heat from a propane torch is enough to drive you to draggin out the oxy-fuel rig and heating that aluminum until it starts to smoke. I know not everyone has an oxy-fuel setup so I didn't say "that's the only thing I use". Plus, a MAPP gas torch is approximately the same purchase price as a propane torch setup and provides A LOT more heat.
For most "general purpose" jobs requiring rosebud heating I recommend a MAPP gas torch anyway, crank bearings included!
MAPP gas torches and propane torches are available at most any hardware store including home depot and lowe's. I did a quick search for MAPP on both their websites and they both carry "benzomatic" self igniting models which are a little pricy (not really any more so than the self igniting propane torch heads though) but I'm sure in store they also have the regular heads.
Propane bottles are blue or green, MAPP gas bottles are yellow. Both torch heads should be VERY clearly marked and I *believe* the MAPP gas torch head has a different thread on it to keep you from using one on the other (different fueling rates)
I've heard of using an oven to heat the case evenly and install bearings that way. There are a few problems.... One, an oven will heat the case perfectly evenly and all of the bearings are interference fit which means if you turn the case over, all of the bearings could come out at the same time. Most people don't have an oven in their garage or work on their quad in the kitchen and transporting the case outside to put bearings in, the case would loose a lot of the heat you've put in it and would probably be too cool to get the bearings in or out.
You COULD use the kitchen oven as a "preheat" and then a propane torch once you get the already hot cases outside to "push it over the edge" to get it hot enough for the bearings to slip in and out....
Thanks SI for the great info, especially holding the bearing in while the case cools. Have a spare motor that needs crank bearings and probably would not have thought about that.
When putting all the parts together does anything go back in a certain way.. Like the balancer turned to a certain position ?
http://www.blasterforum.com/general-support-17/downloadable-yamaha-blaster-manual-17325/
TADA! A service manual for your quad provided free of charge. It has a step by step reassembly guide in the "engine" section.
It shows, step-by-step how to put that baby back together.
TADA! A service manual for your quad provided free of charge. It has a step by step reassembly guide in the "engine" section.
It shows, step-by-step how to put that baby back together.
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