Doing my valve clearances - Updated!

[911f]

I'm planning to check the clearances on my NC30 sometime in the next couple of weeks so I'm in here sponging up as much info as possible.

Viper_Biker: Thanks for the guide in the other thread, very useful info.

Oliherst: Cheers for posting this thread, I would have just followed the photos in the Haynes manual and done the same thing.

I'm getting the impression that it's worth going through and pulling all the shims to get a record of their sizes for future reference and I like having as much info on hand as possible.

It was mentioned earlier in the thread that cranking the engine round with the shims out is a bad idea so I'm wondering what the proper procedure is if you have quite a few shims that need replacing. I guess if you just buy them in new then there is no issue because you can leave them in until replacing them, but what if you want to do a swap? Do the cams have to come out in that case?

I am not sure I agree with removing all the shims and measuring them up so its done. It nice info to have, so you can swap shims instead of buying new ones - but the shim type is one used on a BUNCH of hondas using shim under bucket - so getting individual replacements is easy to do as most shops will have them in stock. Personally, they wear so slowly once an engine is broken in, that I would just remove the ones in need. Unlikely you will need to do much additional adjustment for a very long time. For me, each one I removed was another chance to drop it somewhere. Regarding that - use foil or paper towels but cover any hole they could drop into. you will drop one. And get a narrow, STRONG magnet to help you. The one I had was too large but strong, or too weak but small. helped me to drop them. Cover the holes (sparkplug, tunnels etc - and the rocker arm is spring loaded so it can snap back and ping your shim in all directions so cover cover cover.). But I would say for practice at least, do the easiest to see first and get the hang of it before you have to do the number 2 outer most intake valve. Unless you have a spare shim or two you can't swap a shim without rotating the engine with a shim out. I did this gently to remove a donor shim that swapped perfectly and had no problem. Obviously don't run the engine. You will have to pop the rocker arm out from the shim recess after with a thin driver blade. Or pick up a few spares of the appropriate range size - of course if you put in too big you could have worse issues. Just my 2 cents from doing it recently.

[Jono035]

Cheers for the info. I get what you mean in terms of it being more chances to drop them etc. I'll see how it goes with the tools I have. If it's a pain, I'll leave it otherwise I'd still like to know.

Good warning about the rocker arm flicking back, too, might save a bit of pain and suffering.