Hi Mike, your pic does not seem to show that things are coil bound or close to the guide.
I concur with Peter something is not right with the pulley. Check everything at that end inside too!! Any debris in the oil????
Ian.
Technical vibration / balance
- Thread starter Mike r
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Technical vibration / balance
Hi Mike, your pic does not seem to show that things are coil bound or close to the guide.
I concur with Peter something is not right with the pulley. Check everything at that end inside too!! Any debris in the oil????
Ian.
Hi Mike, even if you feel it's only a small amount of movement on the pulley check it out!!!!! you should have NO movement at all. see copy from previous post " the rocker arm should be parallel at half cam lift"
take out the plugs and rotate the engine until you can measure half lift, if the rocker is not parallel or damn near, reduce the length of the pushrod to suit. BUT be careful doing this the design of the pushrod places a small steel insert down the inside of the hollow rod from the steel rocker cap on top, you cannot just hack off a portion and hope it will work. The steel cap with it's attached insert must remain in one piece!!!!
Ian.
Hi Mike, as far as I am able to determine draw a line between the rocker arm pad (normally in contact with the valve stem) to the lower surface of the threaded area that holds the adjusting screw. As the engine turns you should be able to see if the cam lift is available (what cam do you have fitted and what is the max lift figure) with your fitted pushrod, given the ratio of the rocker you should have max valve opening for the maximum time, But, If the pushrod is too long the valve will open early in the cycle and remain open too long in the cycle. It will depend on your cam and the accuracy of it's timing too. This problem only gets serious with wild cams for racing applications.
Ian.
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Ref Ian's comment regarding the crank-shaft pulley---there should be NO play in it at all. I would follow his advice and get that checked--broken/cracked 'Woodruff' keys are not unknown. As Ian is, from your pictures, of the opinion that there is no problem with your push-rods/rockers, I would get the crank pulley drive checked, and sorted, as a matter of priority
Hi Mike, Yes, BUT, please remember It is all dependant on the Cam you have fitted, the pushrod length, how old your valve springs are AND most importantly what valve guides you have in the head, (I have seen several different types) unless an engineer strips, checks and measures everything you cannot be sure that getting the rocker angle right is going to give you any better valve operation. My engineer is a very picky man, he will always do his best to get the most from an application no matter what level you require. I would get the play in your pulley sorted first.
Ian.
...bad news indeed. But that's a flippin' lot of play. It could even be loose or stretched big-end bolts or a problem with the gudgeon/piston-pin at the "little" end. 
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Hi Mike, for me as the BIS crankshaft was the last of the engine line, and because the counterweight is closer to the longitudinal centreline it seemed the better option. The stroke is standard. A lot of engine makers still use the standard crank for whatever reason and I know of one German company who 'Tuftride' them to stiffen the casting for higher revs. It is simply a case of 'pay your money and take your choice'!!!!
I am using lightweight conrods with standard BIS (80mm) pistons and the balance shop had to drill my BIS crank to get it in balance. It will depend on your parts as how any balance pans out (to add or remove weight) my bearings came from Axel Gerstl
in Germany.
Ian.
