Club 80-90 Forums

I'm trying to set the tappets on my 2ltr CU, and struggling. To understand the Haynes. I get the I/2 turn in from touching as recommended on here, but which ones do I adjust when which one is rocking if that makes sense. Or do I adjust the ones that are rocking? Inline engines, no probs but I can't turn the crank and watch the valves on this one. What I mean is, normally the bokk will say adjust 1&3 when 2&4 are rocking, whereas the Haynes just says adjust 1 at TDC, the turn 45 degrees and adjust 2. Basically, I don't want to mess it up. And also, is there any freeplay at all in the tappets, because there is non in mine no matter where the crank is turned to.

take the rocker covers off, and watch the rockers.
take the dissy cap off, and watch the rotor, when the timing marks line up, the plug lead the rotor is pointing to is at firing point so both vales are closed on that cylinder.
haynes gives you the firing order and the step by step quide.
oh and btw, you need touch and 1/4 turn, not as the haynes says, its wrong.

So are they the ones to adjust then, the ones that the rotor arm is pointing to the lead of?

yes, when both valves are closed the pushrods are under the least pressure...and the rocker arms are furthest out.

yes ..when both are still and the piston is at TDC
you could put a cork in the plug hole and when it pops out that's the compression stroke

I use the the 1 1/2 turns method.
The plunger in the lifter can move a maximum of 4mm in the bore but it would bottom out if it did. In order to keep the spring on the plunger in contact with the lifter body, the spring is compressed just enough (about 1.5mm or 1.5 turns) during manual valve adjustment to center the base of the plunger relative to the bottom of the lifter. When the engine is running the exact amount of adjustment varies with the oil pressure and expansion of the engine. Remember that the design of the lifter is only trying to eliminate a few thousands of an inch of clearance but it must be compressed 15x that in order to prime the check ball cavity.

The construction of the lifter has the tightest manufacturing tolerances of any part in the engine. It's a precision part that is designed to self-adjust based on oil pressures and spring tensions calculated by the factory.

read this article....
http://www.ratwell.com/technical/HydraulicLifters.html" onclick="window.open(this.href);return false;

All you need to know

I found 1 1/2 turns better.
try this site for a pretty good walkthrough
http://greenbug.damiankolbay.com/Tech/H ... djust.html" onclick="window.open(this.href);return false;

Thanks for all the advice guys but just a couple more questions if I may - adjust when cold and been stood for a couple of days, adjust cold but ran the night before or take for a quick run and then adjust when warm?
Oh, and a really dumb question - I take it 1 turn means 360 degrees?
I'm trying to diagnose why my left bank of cylinders seems to be dead as when I remove the leads on that side it makes no difference to the idling, which is lumpy and on the verge of stalling. Also the plug in number 3 is really oily, and I've tried a couple of old plugs and leads to rule out the ignition side of things. If it's not the tappets then I presume it's either a burnt valve, melted piston, that sort of thing, but before I try and take the head off I just want to be 100% it's nothing else first as it's my daily driver.

have you done a compression test. a must i`d say before you start messing with the tappets. if you have good compresssion then methodicaly working through everything else should eventually find the problem. always start with the complaint and work from there. ie " my engine idles roughly... possible causes A+B+C+D+E ect " if you have an oily plug then thats not good but you should still start with a compression test.

I'd love to but my compression tester is in the UK and I'm working in Germany. I might try and buy one locally, but even then it won't neccesarily tell me the problem, hence I'm working my way through everything else. There's a big spark, and I've tried other plugs and leads, albeit old ones and that made no difference. However, when I was adjusting the rocker I notice one of the pushrods wasn't seated properly against the tappet inside the engine, it had fell down and was just resting on the edge of it, so maybe I have a bust hydraulic tappet which would explain the lumpy running, soiled plug and smokey exhaust. It's the inlet on number 3 which is the one that has the has the oily plug. How would I know if I have a bust tappet?

Remove the #3 and #4 side rocker cover, rotate the engine to TDC on #3, then take a screwdriver and try to push in the lower end of the rocker arm on the #3 valves. If it moves, then your tappet is soft.

Removing, cleaning and reassembling soft tappets worked for me, rather than replacing. I'd be wary of putting a new tappet against an old and worn cam lobe.

yes cleaning could help as the tiny oil hole can gum up.
The usual suspect though is the return spring (weak or broken)
The distance from the valve body to end of spring is 8mm any less would indicate a worn or weak spring.