
Originally Posted by
camchain
I've just re-shimmed my valves and found it a very straight forward job. I was worried about getting the cams timed right, but this is easy to do. Happy to give you step by step on how I did it if you like (about 6 steps). I'm glad I did it myself, it's easier to do than it looks at first glance. Fear not your 4 stroke engine.
Was going to take it to a shop but mechanics from 2 local dealers (Mt Eden) were very unhelpful re ballpark figure on hours/cost to do it. I was slow and v careful 1st time. Next time I reckon inside an hour half easy. If you get the shop to do it can you post cost on here? Curious to know.
As far as cam position for checking clearances goes, as long as the lobes are well clear of the top of the buckets (part that cam lobe pushes directly onto), which you can see visually, and they will be off when at TDC compression stroke anyway, you'll get an accurate feeler reading. The valves stay closed a few degrees back or forward off TDC anyway. You only have to be aware if you have a valve lifting auto decompressor on an exhaust valve (If you have one, its the fancy little contraption on the end of your exhaust cam. If it's engaged you'll get a false and very large clearance on one of your exhaust valves. keep rotating engine to observe when it's not engaged. (Also, removing spark plug makes it easier to turn engine over easily and accurately)
BTW and FYI other 4 strokers: Just read some interesting info on modern valves. Standard OEM titanium valves are apparently not as reliable as stainless. The stems are welded to the heads and can fail at the weld (stainless are one piece). Also hardness layer is also very thin, hence need for lots of adjustments once through layer.
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