Rotated the engine withhout a couple of shims in place

Liffa

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Yes...this I just did and I knew instantly that I f*cked up when I couldnt turn the engine 🙈 So it looks like the bucket where the shims sit is in the way for the cam to rotate. What do I do now? I guess I cant rotate the engine the wrong way to put the shims back?? I turned the engine slowly so hopefully nothing is damaged.

I would be very grateful for any advice how not to make it even worse 😂
 
I did the same thing.
If memory serves, I had to push the bucket down (the valve spring is tough, though) to shove a shim in there. Use something that won't gouge into the bucket. I think I also used the valve shim tool to provide a bit more room between the shim and lobe.
Slowly rotate the engine so the cam lobe is at the opposite side of the bucket from where the shim goes in.
Take your time not to bend or break the rim of the bucket. Oil the shim a bit to help.
 
I did the same thing.
If memory serves, I had to push the bucket down (the valve spring is tough, though) to shove a shim in there. Use something that won't gouge into the bucket. I think I also used the valve shim tool to provide a bit more room between the shim and lobe.
Slowly rotate the engine so the cam lobe is at the opposite side of the bucket from where the shim goes in.
Take your time not to bend or break the rim of the bucket. Oil the shim a bit to help.

Ok, thanks for your advice. The lobe is already stuck on the other side of the bucket (exit side). I will see if it is possible to get a shim in at all.
 
This was difficult 😪 What happens if I slowly rotate the engine the wrong way until the lobe exits the bucket on the entry side? Do I risk damagaging somethong else than the bucket?
 
The cam lobe can damage the bucket ridge, increasing risk of any shim that eventually is in there, to shoot out while the engine is running. A shim bouncing around the valve train could cause big problems.
 
The cam lobe can damage the bucket ridge, increasing risk of any shim that eventually is in there, to shoot out while the engine is running. A shim bouncing around the valve train could cause big problems.
Yeah, that would suck. I dont see how i can press the bucket in (from above) when the cam is in the way. Looking at the attached picture, this is the position of the lobe where you managed to put shims in?
 

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The cam lobe can damage the bucket ridge, increasing risk of any shim that eventually is in there, to shoot out while the engine is running. A shim bouncing around the valve train could cause big problems.
I was thinking since the lobe managed to enter the basket without damaging the ridge (at least it looks like it) it would also exit the basket that direction without problems.
 
I don't think that is right. I looked for that option. If the shims don't seat all the way, when the cam lobe presses on the edge of the shim, it will begin to force the shim out as the lobe rotates into the bucket. Eventually the shim is pressed out and the lobe falls into the bucket.
With that said, we change shims via the shim tool, giving us room to get shims out when the cam is out of the way. AND, the cam lobe never touches the bucket when the shim is in place. So, if you have the shim tool in place, you can try prying up on the cam lobe as you slowly rotate the engine to see if you can get enough clearance for it to come out. After all, the cam lobe is high enough to clear the bucket when a shim is pushing against it.
 
I don't think that is right. I looked for that option. If the shims don't seat all the way, when the cam lobe presses on the edge of the shim, it will begin to force the shim out as the lobe rotates into the bucket. Eventually the shim is pressed out and the lobe falls into the bucket.
With that said, we change shims via the shim tool, giving us room to get shims out when the cam is out of the way. AND, the cam lobe never touches the bucket when the shim is in place. So, if you have the shim tool in place, you can try prying up on the cam lobe as you slowly rotate the engine to see if you can get enough clearance for it to come out. After all, the cam lobe is high enough to clear the bucket when a shim is pushing against it.
Yeah, I have the shim tool. I noticed that it leaves some very fine metal shavings after use. This bothers me also 😆

Both cam lobes on cyl4 intake side are stuck in their baskets. This makes it more complicated to create a clearance.

I am thinking I might have to remove the camshaft. I am not sure what this involves and if I can get it back in place myself.

Another idea I have is to cut a shim in half and make two ramps for the lobes to slide on up above the ridges of the baskets couunter clockwise. The shims are super hard I guess, so I would probably have to make the ramps from a softer metal.
 
Not a horrible idea. If you could find something rigid enough that was plastic, you might be able to make a ramp for the lobes, too. I'm thinking like an autonotive trim tool or something.
Unfolding the end of the cam is an option, too. That was my backup plan when I was in your situation. The cam chain will be holding the cam shaft down a bit, but you might even be able to unbolt it around cylinder 4 and use a ramp at the same time.
 
Not a horrible idea. If you could find something rigid enough that was plastic, you might be able to make a ramp for the lobes, too. I'm thinking like an autonotive trim tool or something.
Unfolding the end of the cam is an option, too. That was my backup plan when I was in your situation. The cam chain will be holding the cam shaft down a bit, but you might even be able to unbolt it around cylinder 4 and use a ramp at the same time.
It worked lika a charm! I made the ramps out of a trim tool like you suggested. Inspecting the lobes I can see tiny indents where they hit the baskets. Perhaps sanding the lobes with a very fine grit sanding papper (3000) would work?

I will inspect the baskets more carefully for any damages.
 

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Congrats! Personally, I wouldn't sand the lobes unless there are high spots. And even then, you would need to be careful about metal shavings in your oil. But you're definitely in a better spot!
 
Congrats! Personally, I wouldn't sand the lobes unless there are high spots. And even then, you would need to be careful about metal shavings in your oil. But you're definitely in a better spot!
Hmm. This shim removal tool has left alot of tiny aluminium shavings in the oil. How bad is this? I am fishing around with a magnet in the oil to try and collect as much as possible.

Also, the valve clearance is 0.06mm for almost all valves. I understand 0.13mm is the optimal clearance. So it looks like I will have to replace almost all shims as most are 2.90mm thick. These shims are quite expensive and often comes in increments of 0.05mm. So shall i go for a clearance of 0.11mm or 0.16mm?
 
The spec for these bikes listed in the service manual is too tight and honda acknowledged this later. I just looked at my notes and I didn't write down the updated clearances. I want to say it was 0.08mm to 0.1mm (0.003 - 0.005"). But please look through the forum to verify.
 
The danger of turning the engine with shims missing, is that the cam lobe catches on the raised edge of the bucket, causing the edge to distort and bind in the head when the valve is opened. If the bind is sufficient to hold the valve even slightly open, then valves can foul each other (inlet to exhaust) or contact the piston at TDC.
Personally, I would remove the cam, remove the buckets and discard them, fitting replacements and shimming correctly.
I've never had any issues with swarf forming when the correct tool is used in the correct manner - you're not trying to use the tool as a lever, turning the tool to force the tappet bucket down, are you? The correct method is to insert the tool with the valve at full lift them turn the cam until the lobe is off the shim. You shouldn't be generating swarf if you do it right.
 
Ok, that doesnt sound good. Maybe removing the cam is the way to go then. Is this a big job?

Sounds like I was not using the tool the correct way. I checked a few videos and they all seemed to be using the tool this way. Eg 15 minutes into this video

So this is not how I should use the tool? Material comes off the tool when it slides on and pushes down on the two baskets I guess.
 
Or just grind/sand the coating off.
I am not sure it is coating. I believe the metal is just very soft. I noticed it got harder to use with time as is got somewhat distorted underneath and now only is capable of pressing down one bucket at a time. I cant find the original tool to buy, it would probably cost a fortune anyway :)
 
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