The ISM is IN

[Brian Diehl]

Just a quick update ...

I got the ISM in the bus last night!  Sorry, no pictures yet ....  Tonight I tested removing the valve cover so I can be sure it is possible given the tight space.  I got the engine cradle bolted down and started hooking up all the wiring, plumbing, etc....

Question, does anyone know the correct torque to apply to the U-Bolts holding the cradle down?

[Sam 4106]

Hi Brian,
Congradulations! I am really impressed with your progress. Do you have an estimate for when you will take your first test ride? Keep up the good work.
Sam 4106

[skipn]

Good news is always a happy event.


   So are you making plans on where the first big trip will be to?


   More hard work and more good news (sounds like a Lutheran Ministor/Professor I once knew)


   Skip

[Brian Diehl]

Hey guys,
Thanks for the kind words.

-- I think at this point I will be able to do the first start some time in July and if there are no problems I should be able to do the first test drive shortly after.

-- I am hoping to take a few extended weekend trips this summer.  My main priority is to just put some miles on the bus to work out any bugs/kinks.  I want it running perfectly for my December trip out east for a family event.

I'm taking the drive shaft in to our local heavy duty repair shop tomorrow to find out the damage $$$ involved in getting it shortened.  Holding my breath ....

[bobofthenorth]

I don't know whether you want to tackle shortening the driveshaft yourself but I had a guy working for me one summer who did it while I watched & it really is remarkably easy.  You cut the tube to the right length in a hacksaw.  You grind the old tube off the plug on the yoke.  Then you get the end of the tube hot - not red hot but hot.  When it is hot you quickly stuff the plug into the end of the tube.  Then you weld it.  Apparently what happens is that the tube expands - the plug is cold - that's why it goes in.  Once it is in the plug cools the tube which shrinks tight which is what holds everything straight.  Then you weld it all together.

We were swapping out a diff on a high floatation truck late at night so it would be ready to go back to work in the morning.  I thought we were beat until a machine shop opened up because we needed to shorten the driveshaft.  Glen told us to just get busy and bolt the housing in place while he went and shortened the driveshaft. 

[JackConrad]

If you shorten the driveshaft yourself, when you re-install the "plug", make sure the u-joints are in time. Out of time u-joints will create a terrible vibration.  Jack

[TomC]

If you do it yourself, you should still have it spun balanced-like what a professional shop should do everytime.  Make sure to have this done.  Good Luck, TomC

[captain ron]

If you mark the driveshaft the full length and onto the yoke you should be able to line everything back up as it was following  bobofthenorth's instructions and you should be good to go. Spin balance should be the same but getting it checked won't hurt. Good luck.

[prevost82]

I wouldn't cut it with a hacksaw if the ends are not cut square you will get vibration because the yoke will be cocked. Driveshaft should be cutoff in a lathe with a small land on the face and V-groove the yoke should have the same treatment. This ensures that the yoke and tube are square to each other.

As said the yoke have to be inline with each other before welding. Also some drive shafts are made of DOM or CDSMT and have a smooth bore with no weld seam But some are made from EWST and have a weld seam on the inside that has to be machine out as well as the bore should be machine where the spigot of the yoke will sit it the tube as this tube is rolled and welded.
Ron

[bobofthenorth]

I wouldn't cut it with a hacksaw if the ends are not cut square you will get vibration because the yoke will be cocked.

That's what I would have thought too prior to seeing it done.  There may be a large number of factors which I am not aware of.  We were dealing with seamless tubing so machining out the inside of the tube wasn't an issue.  The plug on the yoke penetrated deeply enough into the tube that it had to end up square, no matter how sloppy the hacksaw cut was.  Once the tube cooled onto the plug it simply had to be square. 

Like I said I was absolutely amazed at how simple a project this actually was.  Sample size of one I know but that truck ran for a lot of years after this particular fix and I know the drive shaft never gave any problems.  As far as I know it is still running. 

[Dallas]

I did the same thing as BOTN talks about on an old KW K100E. It broke the weld at the front yoke in the middle of nowhere, Wyoming and there was no place around to get help. (Look up Buffalo Gap). I had no choice but to fix it myself, so with the help of the rancher who happened to have a Lincoln buzzbox handy, I cut off the rough piece, heated the drive shaft with a propane burner and slipped the yoke back in. After welding it it looked kind of rough, and I figured it would vibrate badly under load or at high speed. My thinking was to get it fixed at the first large town I came to. Unfortunately, it was after 9 pm when I got near town and I had another drop the next morning so I went on.
And on, and on, ....... for 2 more years, until I sold the truck to a guy that used it to haul hay cubes and potatoes in Washington.
I wonder if he ever fixed it?

Dallas

[Brian Diehl]

It turns out the shaft just plain can't be shortened enough.  So, I had to buy all new parts designed for the shorter length I need.  Thanks for all the ideas.