New crank and bearings in the casings but not turning very freely ?

[Awesomesilverado]

kinda tight not as free as I believe they should be, any help ?

[pachanga90]

It sounds like one of the bearings may be cocked in the housing a little,causing it to bind.Try removing the crank,look closely,maybe you can see where one is sitting a little off,or try to lightly tap them in with a small-punch,make sure they fully seat in the bores.Did you put anything on the outsides of the bearings(oil,loctite,grease)alot of times people do this assuming it will aid installation,but it actually can cause them to bind or stop before they seat.Hope this helps.

[madoc1]

try taking a dead blow hammer and hitting the crank at each end. might help seat everything.

[Awesomesilverado]

used a crank puller and a thin coat of grease on the single side, other side used the freezer oven method as well with putting on the bearings on each side.

[pachanga90]

I would have just pressed or driven them on.The interference fit on them is very light.The freezer/oven deal,I wouldn't do,its' fine for bearing-races,but I wouldn't put engine parts thru that,since its' not an even heat/cool change.We used to heat Cam-Gears for Cummins motors in a pan of motor-oil on a hot-plate,that spread the heat evenly thru the entire gear.As I stated earlier,don't lube the shaft or race of the bearing.A press-fit needs to be dry,and any residue can prevent it from seating evenly or bottoming in the bore or shaft.Hope this helps.

[Awesomesilverado]

I have used this method with many two stroke dirt bikes engines and all but most of those have bearing retainers inside the casing, the crank puller is just like a press but instead of taking a chance on warping the crank using a press it just pull's it strait into the casing and a very light film of grease was used just to prevent gaulding and putting shavings in behind the bearing and casing, and every thing seems fine it turns with out binding or hanging its just not as free turning as I "thought" it should be I have never replaced a crank in one of these engines and "was just wondering if it was normal to turn with some resistance" just the crank with new bearings installed in the block with seals installed but no flywheel or cylinder in place.

[felber61]

I just rebuilt by '87 last week and I was slightly worried about the tention that it took to turn the crank with the new bearings installed also. I'm used to 2 stroke bikes also and it seemed to be too much resistance. We did as stated above and tapped the crank ends with a rubber mallet and that helped but with all my worries when I installed the motor the only thing I've noticed is that it takes more to crank it over but once she fires there is no noticable difference in performance. I believe they all must be more snug than what we bikers are used to but that was my first bottom end in a cart so I'm not promising anything just lettin you know my was very similar to what your describing and no problems yet with about 15 hours of moderate to rough use.

[Awesomesilverado]

yeah I have already done the mallet on the crank ends and even used the crank puller on each side to seat the bearings in the casings and it turned pretty freely until I installed the seals and that's when it got tighter than I thought it should have but hey they are just seals lol any way I plan on going ahead with the rest of the build and just go with it, hopefully it will be O.K. I would rather it be a little tight than as loose as it was before the new crank and bearings.

[Awesomesilverado]

do you have a manual for the lower end?

[madoc1]

check out "cart tech" at the top of this forum. go to the thred with the gold stars and find the link to bennetts. they may have what you need.