Shim Issue

[fergy150]

Bought a new engine to use while I'm giving mine a full rebuild, told it was in "perfect working order, only done 16,000 miles" took it apart and found this....



I've scoured the engine put magnetic tool round every nook and cranny, drained the oil and the shim is nowhere to be found.

I put a spare shim in that I had lying around so I could measure its clearance, measured in at 0.422mm, spun engine round by hand a few times and it went down to 0.391mm, spun engine a few more times and was down to 0.385mm.

So question is if I continue to spin the engine/crank it over on starter without starting is it likely to bed in (if thats the right term to use) and return to a reasonable clearance or is it completely knackered and if so whats the easiest way to go about fixing it?

[banner001]

I would simply stick in a correct size shim and leave it at that, check the cams and rocker arm for wear and leave it like that. I would advise you to remove the oil pan and oil filter to see if the shim is in there, its possible of course that someone put the engine together and forgot that particular shim...

You can also check the magnet in the timing cover to see if its stuck there, maybe remove the generator cover too and see if its stuck to the magnets there...

[Miles]

Same thing happened to me. Looked for hours for the shim , in the end fitted a new one and carried on.

A few months later I had to lift the rocker cover and it turned out the missing shim was stuck to the underside of it.

[fergy150]

Thanks for the replies I'll give all of that a go and see how she sounds

[Mxdeano]

Hello there , unfortunately I’ve made the fatal mistake of dropping a shim down an oil well yesterday tried putting magnetic tools down after it to no avail , any advice on where to start from here cheers

[banner001]

the oil drains into the sump, i would take some pipe cleaners and make sure that its not stuck in the oil drain channel.

if its not in there then its sump-off time...

[Mxdeano]

Cheers for the reply , ya I’ll have to take the sump off are those oil drains easily accessible from below in the sump Incase it is lodged in there ? , also with the valve clearance cylinder 4 intake valves read 0.7 and the other .11 can the 0.7 one be shimmed or has it gone to low have not measured the shim yet , got caught looking for the lost one , and finally is it common for there to be quite a bit of resistance for a rocker arm to go back into place over shim as I’ve noticed with one of mine tks

[banner001]

I would drain the oil, if it doesn't flow out of there then it's oilpanoff time and see you can find it in there

I'm assuming you mean a 0.07mm gap, that's too tight so you need a smaller shim.

The rockers shouldn't be tight onto the shims, even a 0.1mm gap will be notified.

[Mxdeano]

Thanks will do , yep 0.7mm was the gap, with the rocker arm I mean I moved it across to the right with a screwdriver to expose shim , but now I’m trying to guide it back left to where it’s supposed to be (over shim) but it will only go half way and stops like something is catching it and I’m afraid to put too much pressure on it Incase I break something, this is all new to me , one thing I’ve learned for sure is I’ll be stuffing rags in them holes in future, nightmare...

[Mxdeano]

Got it out took sump off got no joy there , pulled engine out today was gonna take off the head to see if I could fish it out but before I done anything I turned the engine upside down and gave it a good shake and low and behold out popped the shim , delighted , I think it’s safe to say I’ll never make that mistake again

[banner001]

Yamaha have little fingers on the head gasket that protrude into this hole so oil still flows through, but shims can't get through...amazes me that Kawasaki don't do it too...

Glad you found it, you will remember to use rags when you change yours from now on

[Mxdeano]

Cheers,,Definitely mate , can crack on with it now