Hi Ian, I know of the "Rope trick" but I do not advocate its use as it is a good way to introduce abrasive contaminants into the cylinder. I guess if you did not have access to a compressed air supply & you were really stuck somewhere in the never never it could be a useful LAST RESORT. Also I would NEVER perform a lapping operation on a valve & seat without having the ability to visually inspect the components, and being able to thoroughly remove all traces of the lapping compound. You could not possibly achieve this with the head still on the barrel.
Regards JGV _____ Date: Fri, 7 Nov 2014 20:41:08 +1100 From: [email protected] To: [email protected] Subject: Re: [DOG mailing list] L2000 rocker shaft clip - bent valve? Very interesting John. There is an old (very old) LAME trick to do a valve grind with the head in place. It is feed rope into the spark plug hole with the cylinder near the bottom of stroke. Then bring piston up and thus jams the valves in place then remove springs. THe valve grind only works if you have another plug down the bottom. As after the valve grind you need to wash out the paste through the bottom hole. Only LAMEs 60 years old or more will use this method but trust me it does work. Often done when an engine has say 400hrs to go before TBO. Ian M On 7 November 2014 15:27, salto <[email protected]> wrote: Hi Rob, Been around Limbachs & more particularly VW's for more years than I like to remember now & although I know of clip failures (rare) I have never come across a bent valve as a result, so I doubt that is the cause of your distress. You can dismount the valve springs without removing the head:-you need to pressurise the cylinder using an adapter made from an old spark plug bottom end welded to an air line fitting. Once you have the rocker shaft off it will not matter where the cam is: the cylinder will pressurise, but make sure piston is at Bottom dead centre first or prop could whip around on you. Once the valve springs are off I always secure the valve(s) by using a bit of lockwire about 6" or so, secured in the collet grooves to stop the valve falling into the cylinder and also so that I can pull the valve back up. Once this is done you can decompress the cylinder and ease the valve down the guide. Any stem damage will be obvious. Hope this helps Regards JGV on 05/11/2014 8:22 PM, "Rob Thompson" <[email protected]> wrote: G'day All, After our L2000 rocker shaft clip popped off things haven't gone so well. I replaced all the clips on both side rockers but it is now running quite badly with a noticeable chatter at higher RPM's and a loss of power. I am suspecting that the sideways movement of the rocker after the clip came off may have bent the valve and it is sticking. It is not a bent pushrod. Has anyone had similar experiences? Rob Rob Thompson 0429 493828 Please note that my new email address is [email protected]
