Hairline cracks in case from cam bushing

[james]

It looks like I have 2 hairline cracks in my right side case half at the cam bushing. They are about 1 and 2 inches long.
How worried should I be?
If I should be worried what are my options.

At least they look like cracks, casting marks, I don't think so.

Need some answers from experience.

Thanks, Jim

Buy the way does this forum always get sort of dry towards winter?
Nothing real exciting lately, except for that case number, 47 panhead thing everyone was getting all twisted over.

think Spring

[fourthgear]

Its not cracks with out photos ! LOL
Some photos would help ,if ya can.
Ya winter does slow things down a bit . Wait till spring when those who have waited to do some work on there bikes, to get rolling again.
Hell , I rode to work today for the first time in almost two weeks. Had to think about where the volume was for the tunes on the Ultra.

[Panacea]

Fourthgear, is that the ultra mega supra?...Mike

[mbskeam]

need a pic,
fix it while they are small. trust me on this, I know...LOL

Clipboard14.jpg

[fourthgear]

Fourthgear, is that the ultra mega supra?...Mike

Yes , I'm now spoiled , my Pans are sitting collecting dust. I know WTF ,but I work six days a week and riding to work is all I have time for & thats why I bought the "03 " Ultra , its a work bike . Never had it so good , cruse & tunes & all that fairing ,almost makes it too easy to ride in the rain. Its in the upper sixty's down here , sorry ,I had to bring that up .

Jim
If it looks like mbskeam"s , he gives good advice.

mbskeam

Damn ,that sux , putnear ate your motor. Did it make a lot of noise ?

[Underdoggie]

[quote="mbskeam"]need a pic,
fix it while they are small. trust me on this, I know...LOL[quote]

Mike,
I am interested in your repair. Did you remachine the cam bushing bore and faces on location after the repair? I am interested in how you set that up. I am in the process of doing the same thing for a buddy of mine on a 49 case. It is cracked at 12, 3, 6 and 9 O'clock. On his I set up the cover establishing a centerline thru the cam and crank, then found the position of all the bores. Using those numbers I then set up the case using the two dowels and cover face to verify position of the same features in the case, everything checked less than .002" except for the cracked cam bore which was O/S and out of round by .007". I then created an AutoCAD layout of the case with all the dimensions. My plan is to use those numbers to go back and establish the bore and faces after weld. It looks like my weld approach is a bit different than yours. I took a .250" end mill and cut thru the bore removing .12" at the four positions on the I.D. then with a 90 degree end mill cut into the face about .3" deep in the four cracks on both sides of the top and bottom of the cam bore boss. Here is a couple of shots of the set up, If I can figure out how to attach a PDF I will send the AutoCAD layout later, I forgot to take pictures of the cuts I made for the welder. What are your thoughts on this approach.

Checking the cover in X

DSC02402.jpg

Checking the cover in Y

DSC02404.jpg

Zeroing in on the lower dowel for X & Y and using the other dowel for Z rotation

DSC02455.jpg

[Underdoggie]

OK, Here is the AutoCAD layout I mentioned previously. This particular view lists the descriptions of all the features I recorded measuremnts for. The actual dimensions are shown on another layer.

Bradcase.jpg

[fourthgear]

Impressive ! I believe the two bushings (cam )are line honed though, but I have seen people change the whole gear case cover & work fine .

[Underdoggie]

Impressive ! I believe the two bushings (cam )are line honed though, but I have seen people change the whole gear case cover & work fine .

Yeah, I plan on line honing after I bore the aluminum, press in a bushing and bring it close to size.

[mbskeam]

see if we match up.....

casemeasurements.jpg

this was given to me some time ago, and I was wondering if it is correct.

very cool as to what you did.....

[fourthgear]

mbskeam,That looks like a Shovelhead cam chest. Are the demensions the same as a Pan motor ?

[RUBONE]

fourthgear,
You weren't asking me but I saw your question. Yes, all the dimensions are the same in a Shovel camchest and a Pan. In fact those dimensions go back to 1936 and run through the Evo engines. Differences occur in diameters but not center to center measurements and layout.
Robbie

[mbskeam]

as to the cuts into the alum. for welding. I/we cut about 1/2 way thru in a V, then flip the part over and do the same on the opp side. this lets the weld have full penetration, just dont cut the groove real wide or the case will pull around more than it has too.
you should think of clamping the case and set a support under the pinion boss area and clamping this with a thru stud, this will hold the case as you put the heat to it when in the oven when it is preheated to 450deg and when it is welded, when done welding put back into oven and allow to cool down slow.

[fourthgear]

fourthgear,
You weren't asking me but I saw your question. Yes, all the dimensions are the same in a Shovel camchest and a Pan. In fact those dimensions go back to 1936 and run through the Evo engines. Differences occur in diameters but not center to center measurements and layout.
Robbie

Ya , after I thought about it , they didn't change a whole lot in there , just got rid of the gen. & circuit breaker (timer/distributor, what ever ).

[mbskeam]

when my bushing spun at 2000 miles, I was getting on it going up a hill, I do remember the bike slowing down and making a high pitched squeal, about 2-3 sec. and then it took back off again, rode for about a week more like this, and then a piece of the case got into the oil pump and sheared off the key, was only about 1/4 miles from home.
found it when I took it apart.... fixed it, then. rode for about 3000 more miles

at 5000 miles I decided to just pull it apart to fix some leaks, kinda funny about those ya know, then I went and re-trued up the cases back to 45deg on the decks and within .001 to the crank pin center-line from the deck surface.
put them under my bench for about 3 weeks, and when I went to clean them up I found bigger and more cracks that showed up when I used lacquer thinner to clean up the cases real good, surface dried but the cracks stayed wet.
got a diffrent case and when I went to put the crank in I found it had .015 run-out at the end of the pinion. this was from my pinion bottoming out in the flywheel, the taper was to wide and the shoulder was flush with the inside of the wheel, this is what I believe lead up to the case cracking in the 1st place. twice...LOL

am interested in your repair. Did you remachine the cam bushing bore and faces on location after the repair?

yes to both....