Here is a picture of my cam cover. As you can see it has a crack through one of the oil holes where the bushing goes. Is this something that happenes often? Is it fixable or should I just get a new one. Thanks for your help.


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What model bike is this from?

But, would not chance trying to fix. Looks like it needs to be replaced.

 

Oh man, I hate to be the one to tell you this, but the cover should be replaced. That crack is at the rear intake-cam/ignition. Replacing the cover is a very big deal however! See my recent post on what is involved in doing that.

You may want to first want to take it to an indy shop that does Tig welding. Ask them their opinion on giving it a little Tig heat and touching an aluminum rod to it just to join it back together.
If they say they cannot do that without deforming the bronze bushing, then you are faced with the problem of finding another cover and the agony of the install.
I wish I had better news, but that's the story. Good luck on getting it Tig tacked back together.......pg

 

Well the crack is big enough the bushing will fall right out, so I think I will just replace it. I thought that might be the best bet, but just wanted to make sure...Thanks again for you help pinion

 

The bushing falls out because of the expanded aluminum is no longer holding the bushing tight of course. All of the bushings hold the outboard ends of the camshafts and the end of the piniongear shaft at the bottom.. The inboard ends of the cams sit in needle bearings, fit to the crankcase right half.
The bushings for another timing cover have to be line reamed so the the camshafts line up without binding. Then the cams have to be shimmed with the .005 and .007 shims to establish the correct end play.
Line reaming the bushings requires that the engine cases be split and the entire engine dis-assembled. That is why it is such a big deal.........pg

 

There is 2 optios you find new cam case and you need to line reamed to line cams. Or you TIG-weld old case and line reamed it as PG told. Shimming cams is the easy part of project.
The "big deal" is as PG wrote what ever you do you need disassemble whole engine to split cases, there isn't any easy way to do it or walk a rounds. Atleast so that you can relay that it won't broke it at next week.

 

Well the engine is down to the caseand I am putting new cams and bushings in itso I was going to have to reem it anyway.I figure I might as well get a new cover instead of fixing this one and wondering if it is going to brake again. Thanks again for the great advise guys...

 

If the bushings are reamed properly and the cams are installed shimmed to spec, you should never have a problem again, particularly having a timing cover crack.
I tell you truth, I have never seen a cover crack before like yours, and I suspect someone got something caught in between the cam gears when the engine was running to have done such damage.
Maybe sepxlh will weigh in here with his thoughts on what the cause may have been?.........pg

 

Ya Pinion I think you are right...This is the engine I was telling you had the 2 shims laying in the botton of the case and they were pretty ate up. The cam had deep scratches and gouges on the lobe and where it goes in the bushing. I dont know the proper name for it, but the piece that goes by the bearings that goes next to the lobe and conects 2 cams it has to be some kind of thrust washer or something..I hope I described it good enough so you know what I am talking about. Anyway it has scratches and bluing on it so I am pretty sure there was alot of things going wrong in there.

I dont know how many shims it usually takes to shim a cam, but that one cam had the2 that were in the bottom of the case which were originaly out by the bushing (there was pieces of the shims welded to the gear) and two other shims next to the thrust washer thing.thosewere blued a little bit but still in one piece.

 

Yep, I know what you are talking about there. The plates are called cam gear plates and there are two of them. The shims are called cam shaft washers and they come in 2 different thickness......005 and .007 inch thick. I call them shims myself. These fit on the cam shaft between the cam and the cam gear plate. The number of shims it takes depends on the dimension of your particular engine.

The washers are prone to slip off as you are installing the cams. So that is what happened to yours. Someone had the cams out, did not know what they were doing most likely and dropped some of the shims while trying to get the cams installed. Buttoned up the timing cover with the improper cam end play and a few loose shims floating around in the bottom of the cover.
Started the bike and one or more shims gets picked up and run through the gears.....crunch! There goes your cover. Blue cam plates tells me that it got hot inside,

When you replace the bronze bushings in the cover, also install a new set of needle bearings in the case side. These took a whack when all that stuff happened and now is the time to fix it.
The shims are used to set the cams end play.

When the time comes, install the cam plates and cams.
Have the lifters and housings out of the engine.
Put a dry gasket on the cover and bolt on the cover tight using all of the screws except the generator bolts.
With a screwdriver and the lobe of each cam sticking straight up, move the cam toward the cover as far as it will go.
Then take feeler gages and determine what the space is between the cam and the cam plate. Write it down for that particular cam.
Do each of the other 3 cams, repeating the exercise for each.
Now you can take it apart and use those .005 and .007 shims to get the correct end play in each cam.
The cam end play is a minimum of .001 and a maximum of .005 inch.
Build a stack of washers to obtain the correct end play clearance and put them on the respective cam.

When you do this you need the factory manual in front of you. Installing the cams requires shimming the cams as I described, and also will require timing the oil pump breather and the cam timing before you button up that cover for the last time.

I could describe it here, but you are quite a ways off from needing that now and it will be better for you to have the manual in front of you. Got any questions, just ask. Someone here will have the answer..........pg