Lash Adjustment Procedure

[Boostedtsi]

I need the lash adjustment procedure for a 1987 conquest tsi. these are mechanical lifters and im using a stock head. thanks.

[JAinsworth]

Here is some instructions per Shelby:

 

Adj. tappets will always be heard,

I've also found that the best results are doing the adjustment on a hot engine, hot meaning recently ran, not necessary to be 190 degrees , and i use .006 for the intake and .009 for the exh., also go back over the valves after you have done them a couple of times. Time can be saved if you go by firing order , do only the intakes first, then do the exh., when right the .006 should have a little drag on it when going under the tappet, if it is real loose the lash is not tight enough, to double check your self use a .007 if it goes in then you know your too loose

 

i place the feeler gauge in place and snug down the adj. until the feller can't be moved easily now lock the adj. nut and the pull on the threads will give you the clearance you need to move the feller gauge, it takes a bit of practice to get it right but it's not hard to learn the feel , our engines increase the valve lash as the engine heats up unlike most cars

 

also never use the starter to turn the engine use a wrench on the crank pulley to turn it clockwise , never back it up , and i have found many cams that have low spots on the base circle , meaning there are spots that maybe a .001 or so smaller then other spots , if you hit a high spot on the base to ad.j the lash it can be loose at other spots , also the base of the cam lobe where the rocker starts to raise can have a bit of wear , this can cause a valve to sounds looser then it really is , the major thing is to have them all even with none making more noise then the rest,, and NEVER try to make them as quiet as hyd lifters that’s asking for trouble , you will always hear the lifter click that’s normal

there are some late model engine s that the injs make more noise then solid lifters when they are running, some injs. are very noisy when working

[Boostedtsi]

thank you for your reply.

after i place everything to TDC, i adj the clearance (lash adjuster) of cyl 1 (what clearance do i use?); next, where do i stop after turning the crank pulley to adjust the lash adjuster for the cyl 2? i apologize for my limited knowledge

[mikec]

Look at the rocker arms... the end opposite the lash screw rides on the camshaft. You'll see the cam lobes are exaggerated egg shapes. Turn the engine crankshaft pulley bolt (clockwise only as you face the engine!) to put the rocker arm on the "low" spot of the camshaft opposite the "peak." That low spot is when the valve should be closed and the rocker should be "loose." As Shelby posted the "low spot" on the camshaft lobes may not be constant... so you'll have to slowly turn the engine until the rocker slides down the ramp... now measure the valve clearance. Turn the engine just a little bit (quarter turn at the crankshaft) and measure again. Keep doing this until the rocker arm is getting close to riding up the ramp again. Turn the engine over (and over... it'll take a couple revolutions) to get back to whatever was the lowest of the low spots --> wherever the clearance was highest. Remember the crankshaft has to make 2 full turns/revolutions for each camshaft revolution.

 

Since you have an 87 do you have lash adjustment screws on all valves or on just the dinky "jet" valves on the intake side of the cylinder head? 87s came with auto-lash adjusters on the main valves - nothing for you to adjust there. Rocker arms with auto-lash adjusters should NEVER be loose no matter where the rocker is on the cam lobe. If the rocker arm "rocks" (is loose) when you have auto-lash adjusters then the lash adjuster is bad (jammed, or the oil inlet hole is plugged), the oil line through the rocker arm shaft or rocker arm itself is plugged, etc. Whatever, things need to be taken apart and fully cleaned. Also, worn rocker arms can have damage in the part holding the auto-lash adjuster pill... the hole gets mashed too deep for the auto-lash adjuster to do its job. The jet valve clearance is 0.0098 inches on a warmed-up engine, 0.0067 inches on a cold engine. (0.25millimeters & 0.17 millimeters if you have metric feeler gauges).

 

mike c.