Don't be misled by this video. While the process shown is perfectly adequate, there was a lot of truing done off camera, I'm certain. There is no way a crank ever assembles this accurately in the press before dropping in the truing stand. Even using a die-set to position the halves very accurately, this still doesn't happen. Typically when just using a press such as in this video, the 2nd crank half is pressed onto the crankpin just a very small distance, and then the crank is trued fairly closely. Then press it further, and check/true again. This process is repeated a few times during assembly, because it's MUCH easier to true ("clock") the crank halves before the crank is fully assembled. The video is nicely done, and a clever use of other parts to build the indicating stand, however the video simply does not show the entire process. Be advised. :-)
I have several custom fixtures I have built over the years, especially for multicylinder Jet Skis and snowmobile engines,, that allow me to get extremely close to "dead on" straight cranks right out of the press. Back in the days of two stoke watercraft I averaged at least 1 crank rebuild a day thus the need for the fixtures: efficiency and speed.
For a single cylinder crankshaft like these, its nothing complicated really, we usually press it right away, then hit it, it will come out good, if the part is good. If it doesnt, then there are something wrong with the part, either the shaft is deformed or the crankpin hole isnt in correct distance or angle, which mean any further adjustment is impossible.
Hey Paul. Love the Crankshaft Truing stand. Always makes life easier when you have the right equipment for the job. Thanks for posting the video. All the best. Peter.
blackdaan He has left out a few “ tricks of the trade “ . Notice he seems only to true up one side , but the jig is designed to do both . You can do it with just one gauge but you have to keep swapping sides and sometimes it impossible to get both sides perfect at the same time
E. Duarte not true , you can have different amounts of run out on each side , right up to the point that you can have zero on one side and some on the other .
one thing still seems very mysterious.....how do you decide exactly where to strike with the copper hammer? does the dial indicator point at the correct spot? do you always strike the crankshaft flange? i suppose you learn by trial and error
Its simple really, there is only one hinge between 2 flange, when we hit it we only position the hinge either on the top or the bottom, and then hit the middle. If the dial get worse, rotate 180 and hit the middle again.
Actually its the best option, If your bearing failed then you are pressing the damaged part of the pin through the crank, this way you press the cut pins toward the center saving the crank bores from galling.
Can I ask how you know what point of the crank to hit when reading the gauges? As I can get mine good but I get lost on knowing what points to hit when reading the guages. Its The only think holding me back.. thanks
@@PaulXchannel so for instance.. if your on the flywheel side and the guage is at its highest point (with the rod furthest away) would you hit the primary side or the flywheel side? Thanks for your reply
04:00 not parallel by a long shot, or it's just the filming? no need to reposition,or hit it with the copper hammer to bring it to parallelism before assembling,you feel? also,no need to use the indicator on the left? thanks,nice video.
Ahm is plenty of room on left side. Key way not taking up all of crank area. Full hack even using a grinder. Tipping its a backyard crank job lol. Why post this shit teaching younger kids to grind away... you have a press and you use a grinder. Fukwit
Thank you for posting this. I've never attempted to repair one myself but watching this gives me confidence. Is there any advice you could offer to someone like me? Sub'd and liked👍
Hi , because it is better for crank. No bad pressure for crank when disconnecting. Sometimes can a thin motocross crank burst. Then is better crank cut.
It goes a lot easier if you just start the other side on 1/3 of the way then check and adjust. Then press it down 2/3 of the way, check and adjust, then all the way and check. The way your doing it by pressing it on the whole way then truing makes it much harder to get it to move where you want it.
Hi, because it is better for crank.No bad pressure for crank when disconnecting.Sometimes can a thin motocross crank burst. Then is better crakn cut. It is preventiv against demaging of crank.
Its easier to press half of a pin out than trying to press a full pin out common sense it not gunner hurt nothing is it if the rod is nackerd in the first place dont get why this lad has got so many thumbs down when all he has done is used is head and done it the easier way instead of coursing damage by pushing a full pin out
Hi , because it is better for crank. No bad pressure for crank when disconnecting. Sometimes can a thin motocross crank burst. Then is better crank cut. See my another video with standard disconnecting.
Hi . Because it is better for crank. No bad pressure for crank when disconnecting. Sometimes can a thin motocross crank burst. Then is better crank cut. See my another video with standard disconnecting crankshafts.
Hi. What is wrong with this procedure? Or how do you do that? Give a link to your work. Thank you for your interest. Look on my other videos another videos about crankshaft balansing.
hrmmm.. i believe i can make one of those truing stands. gonna give a shot. im thinking a nice sheet of 1/4 steel. maybe 1.5 foot by 1.5. 2 dial stands. some steel and some bearings. along with a caliper and i think could make one for about 150 bucks to 250.
If you can budget the extra cost I prefer and use an air over hydraulic. They are more controllable when it gets down to the final millimeters of moving parts.
Use a 10mm sheet of glass with 80 grade wet and dry sandpaper and smooth off the crank webs if the scoring marks are more than 0.5 mm deep ,, don’t bother just buy a new crank ,, but if the are less than 0.5 reface then so you can get the correct conrod side clearance of 0.15 to 0.5 depending on the model ,,, make sure your conrod side clearance is within spec this is 100 times mor important than the outside width of the crank webs ,,,
I doing this more than 15 years. Some important moments are not record.... And at the end you check the shaft only on the clutch side??!. It is always necessary on the both sides (clutch and magneto) at the same time!
