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View Full Version : lashing valves? (move to M,T&R)



medivh66
12-04-2004, 04:03 PM
not really sure what it means but im told its a good idea to do it every 20k miles. i know it has to do with putting the cam back into spec or something. also if anybody wants to purchase/send me a dinan chip it would be much appreciated.

Dr.Auto
12-04-2004, 07:02 PM
The reccommended interval according to toyota is every 60K miles. It is not difficult at all if you understend what it is that you're doing. All you are doing is checking the clearance between the cam and the valve /bucket/shim assembly. Too loose and it gets noisey (and doesn't open the valve as much in thousands of an inch however) too tight and you can burn a valve. Thats the main reason why you should do it.

The way to check them is once the valve cover is off you just use a feeler guage to determine the clearance with the cam lobe pointing up as to get a accurate reading. you should also check them cold.

medivh66
12-04-2004, 10:27 PM
yeah mine could be a little quieter. what would you do to fix them if there is too much of a gap. oh yeah and this is on a bmw by the way.

Dr.Auto
12-05-2004, 04:40 AM
I am not familular with BMW valvetrain setup. If I were you I would verify the type of valvetrain setup you have first as there are a few types.
One is hydrolic lifter which are either good or bad and cannot be adjusted for the most part (with some exceptions like older chevy small blocks).
The other would be screw type. You just have to loosen up an ajuster screw and adjust it to the correct lash with a feeler guage.
The other (which toyota is famous for) is shim and bucket. The cam is dirrectly over the valve itself with no rocker arms. there is a bore cut in the cyl hea with a bucket that goes in the bore than sets on top of the valve. Dependant upon manufacturer and/or application there is a shim installed into the bucket either on top of or inside. You shange the thickness of the shim to adjust valve lash. This method is the most difficult and the most expensive. You need spacial tools, and a selection of shims to choose from. The dealership has shims that you can go and get but need to have already measured lash, measured shims and already know what you need to correct it.

If you want to know even more I can elaborate ....let me know.

Sean
12-05-2004, 10:52 AM
Very good advice given up above!

Adjusting the valves/ lashing the valves can be simple, or it can be complicated. I imagine on a BMW, it would be a lot more involved then the older 350's im use to working on. My experience probably wouldnt help out to much hear, i just know that its a pretty involved process.