Page 1 of 2 12 LastLast
Results 1 to 10 of 12
  1. #1
    steve45's Avatar
    Join Date
    Feb 2008
    Location
    Texas
    Posts
    6,835
    +1
    656

    Aluminum Crankshaft

    Ha! Thought that would get your attention!

    I've been wishing that there was a way to put a 4-stroke engine in a Kawasaki Ultra 150. Many thanks to Ultra 15F for leading the way by installing the Kawasaki 1500 cc 4-stroke in his Ultra 150.

    I had the privilege of visiting him a couple of months ago and seeing his 'Ski in person. He has done a beautiful job on it. He has been quite helpful and encouraging to me with my conversion.

    One thing he suggested was to find a blown up engine to strip down and use as a pattern when installing different engine mounts and getting everything aligned. Trying to do this with a complete 150 pound engine would be a royal PITA. Using just the case and crankshaft is much lighter and easier to move. However, I was surprised at how much the crankshaft weighed (I'm used to 2-strokes).

    I had a piece of aluminum bar stock laying around in my shop and decided to make a stub shaft out of it to get the proper spacing and alignment for the driveshaft coupling. It probably saves 25 pounds or more. Here's what it looks like:



    My case did not have the crankshaft bushings, so I put the case halves together and measured the diameter of the bearing web where the bushings go. I made my stub shaft that diameter. I had some trouble getting it to fit because the holes were not round. Notice the hole in the PTO end of the case. I guess that rear bearing took a beating.

    I don't know why I made it so long, I didn't have to, but it only adds a few ounces. I still have to make a couple of bearing caps to hold it in place instead of having to install the top half of the case.

    Just thought I'd pass this along to anyone that is swapping engines. Hopefully it will make your job a lot easier!
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Aluminum Crankshaft.jpg 
Views:	152 
Size:	73.6 KB 
ID:	456018  


  2. #2
    LPG256's Avatar
    Join Date
    May 2009
    Location
    NOBLESVILLE, IN
    Posts
    111
    +1
    14
    Good looking piece. I'm in the same process on my 4-tec build. I was about to just throw a crank on the chop saw.

  3. #3
    steve45's Avatar
    Join Date
    Feb 2008
    Location
    Texas
    Posts
    6,835
    +1
    656
    It's easy if you have a lathe. And, if you don't, it's a good excuse to go buy one!

  4. #4

    Join Date
    Mar 2010
    Location
    Long Island, NY
    Posts
    853
    +1
    74
    Couldn't you just rig up the stock output shaft to do the same thing? I know it's on the short side, but you could probably stick the end of a broom handle into the output shaft to extend it. Wouldn't be quite as nice as yours, but could be rigged up in 5 minutes without a lathe.

  5. +1 by:


  6. #5

    Join Date
    Mar 2010
    Location
    Long Island, NY
    Posts
    853
    +1
    74
    BTW - Ultra 15F bought some Ultra 260 cams from me to see if the bigger lobes improved performance on the 15F motor. Wondering if they made a difference???

  7. #6
    Ultra 15f's Avatar
    Join Date
    Jan 2014
    Location
    Overland Park, KS
    Posts
    145
    +1
    27
    Nice work steve45. Yes grumpy i did get those cams installed but to get any real gain from them i had to put a set of adjustable gears on them from kawi preformance. The cams definitely made a difference on the bottom and mid range, i didnt have any better top end.

  8. #7
    steve45's Avatar
    Join Date
    Feb 2008
    Location
    Texas
    Posts
    6,835
    +1
    656
    Quote Originally Posted by grumpy_steven View Post
    Couldn't you just rig up the stock output shaft to do the same thing? I know it's on the short side, but you could probably stick the end of a broom handle into the output shaft to extend it. Wouldn't be quite as nice as yours, but could be rigged up in 5 minutes without a lathe.
    Well, I suppose. However, the length and centering are somewhat critical. You really want the coupling in the correct position relative to the engine mounts.

  9. #8

    Join Date
    Mar 2010
    Location
    Long Island, NY
    Posts
    853
    +1
    74
    Well, Steve... your metal-working talents are impressive. I'd never be able to do something like this, so I'd have to go with the broom handle and maybe add the rear cover to help with centering and positioning. I'd use the all-purpose solution to everything, duct tape, as a bushing to center the broom handle on the crankshaft supports.

    Your shop cart is also quite an accomplishment.

    There's one more tool you need to add to your shop... a patent lawyer. Once you get the patents on that cart, I'll watch for you on Shark Tank.

  10. #9

    Join Date
    Mar 2010
    Location
    Long Island, NY
    Posts
    853
    +1
    74
    Some observations about what you're doing...

    Don't you need the top half of the crankcase to attach the front motor mount brackets?

    Don't you also need the rear cover for the same reason?

    Is the coupling on your template far enough to the rear? It looks like the coupling is way too close to the block.
    Last edited by grumpy_steven; 11-18-2019 at 09:19 AM.

  11. +1 by:


  12. #10
    My name is Sean and I am addicted to STXs smokeysevin's Avatar
    Join Date
    May 2008
    Location
    Houston
    Posts
    4,774
    +1
    359
    Quote Originally Posted by grumpy_steven View Post
    Some observations about what you're doing...

    Don't you need the top half of the crankcase to attach the front motor mount brackets?

    Don't you also need the rear cover for the same reason?

    Is the coupling on your template far enough to the rear? It looks like the coupling is way too close to the block.
    I agree, the coupler is probably too close. The rear output shaft bearing is a pretty tight fit to the output stub shaft iirc and has the rear motor mounts cast into it.

    I have one our now of you want it Steve.

    Sean

Page 1 of 2 12 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Replies: 1
    Last Post: 06-04-2013, 02:30 PM
  2. zinc anode or aluminum anode (combination of aluminum,zinc and indiumon) for jetski
    By rotortiller in forum Kawasaki PWC Performance (4-stroke)
    Replies: 23
    Last Post: 01-03-2013, 10:08 PM
  3. Replies: 11
    Last Post: 04-12-2011, 11:35 AM
  4. aluminum shavings
    By Jason Durham in forum 2-Stroke Performance
    Replies: 12
    Last Post: 01-18-2011, 07:22 PM
  5. Aluminum stand
    By L Carlson in forum Kawasaki Classifieds
    Replies: 3
    Last Post: 03-21-2009, 02:47 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •