Nonwoven29

So it's a 86 tpi lb9.

I had the engine out for all new seals rebuilding the heads. The machine shop reused the valves I beleave 3 angle valve job,resurfaced not decked ,new federal mogul Oem springs and seals etc.

New comp flat tappet lifters, reused the pushrods, new summit 1.5 stamped roller tip rockers,comp baby cam #12-388-4

New double roller crane timing gear set. New composite head gasket and bolts all TQ to specs,new 55hv GM oil pump.

I have the no1 cyl tdc, both lifters are down on the no1. 0 mark at the balancer yet when I just start to snug remove the lash the dam thing dosent spin freely like there physical interference. Yes all spark plugs are removed.

Very annoying I'm trying to figure this issue out so I can stuff this engine back in the Iroc. Any ideas as to why it's like this?? Key way is pointing perfect at the no 1 and the marks are a perfect 6 o'clock and 12 o'clock cam/crank???

I would find it real hard to beleave that a name brand like crane would've misaligned the marks on the gear sets?

Any help would be awsome guys!

Nonwoven29

I also ment to say the machine shop also installed all new valve guides and stem seals. I also noticed that when trying to follow the chilton manual i couldn't get the no 4 and 8 exhuast valves since they where not seated in the bore all the way partially up.


























Timing gear sets at a perfect 6&12<br/>

Nonwoven29

I think i maybe adjusting the rockers to tight. I see guys are saying to spin the push robs just til they stop and than the 1/3 turn past zero lash.

Is this the same for my roller tip rockers ad well??

85Special

My advice would be to set your valves to zero lash TDC one cyl at a time, than do the valve adjustment live.

Start the engine one velve cover off and allow the oil to start flowing back the rocker off till it taps back till it stops than 1/4 turn. It's messy and ole scool but it works. Type of rocker doesn't matter. If you need a photo of a round camshaft to motivate you I can provide it lol. I tried to preload it too and bad things happened.

MrPackstin

iTrader: (9)

It should be difficult to spin, but really no different than before all this work. I would zero lash it for now while test spinning with the harmonic balancer bolt...maybe around 20 ft. lbs. Maybe someone has more precise figures on this. Removing distributor...does that change things, spins freely out of the engine. Spin oil pump with long screwdriver, difficult/binding?

Cam went in smooth and rotates smoothly with push rods, rockers and timing chain removed? Be careful here to not scar the cam bearings. Can you scan the instructions to the timing gear/chain set and post them? My setup (not the same as yours) stated to put the circle on the cam gear at 12. Lubed cam lobes VERY generously before installing?

When "spinning" does is it difficult or stops abruptly?

It could be slightly more difficult to spin resulting from stiffer springs for the lift added by the cam. Did machine shop mention this?

This is my precursory inclinations.

big hammer

1.

MrPackstin

iTrader: (9)

That is what I was getting at....It really doesn't matter though because the plugs are out and he is just rotating it by hand on the engine stand so it should rotate at about 20 ft. lbs.

Are you 100% sure that is the correct notch for the crank gear?

big hammer

Try this.

Put the dot on the cam gear to the top.

Adjust both the intake and exhaust valves on #1 to a half turn past zero lash.

Spin the crank 1/4 turn.

Now adjust the # 8 intake and exhaust valves a half turn last zero lash.

Spin the engine 1/4 turn again

Do # 4

Spin the engine 1/4 turn again

Follow the firing order until they're all done

big hammer

I like 1/3, some guys like 1/2. Either are fine. 1 turn is too much IMO.

tmoble

that method as given in pics is bad. It's for old time flat-raters working on stock engines with stock cams and doesn't work very well even with them. With non-stock cams it's no good at all. it has you adjusting valves that are not on the base circle of the lobe.

Try this method, well known since the 80's, will work correctly on any 4 stroke engine with any cam.

with stock rocker nuts:

spinning the pushrod with fingers is just a way to find the zero lash point.

back off all your rocker nuts at least two full turns. turn the engine with balancer bolt or remote starter switch till #1 exhaust just starts to open. judge this by eye, you can see it the pushrod move up. Turn the intake nut down to zero lash, confirm by rattling the pushrod up and down and spinning until the play goes out. adjust the intake to 3/4 turn preload. Look at number 8, turn the engine 1/4 turn, see the #8 exhaust pushrod start to move up, adjust the #8 intake as on #1. then turn the engine 1/4 turn, see the #4 exhaust pushrod start to come up, adjust the #4 intake as before. go thru the firing order 1-8-4-3-6-5-7-2. back to #1, turn the engine till the #1 intake valve goes to full open and starts to close, it will take like a full turn of the engine. adjust the #1 exhaust like all the others. turn the engine 1/4 turn, see the #8 intake go to full open and start to close. adjust the #8 exhaust as before. Give the engine 1/4 turn, see the #4 intake go full open and start to close. adjust the #4 exhaust as before. go the rest of the way through the firing order as before. Sanity check: when done all the nuts should be about the same height with about the same amount of threads of rocker stud sticking out. If any are way off do that valve again. This method ensures that the lifter is on the base circle of the lobe when you're adjusting the valve. Incidentally, when the dots on the timing gears are together, 6:00 on the cam gear and 12:00 on the crank gear, the engine is at TDC on the firing stroke for #6 cylinder, not #1. This is due to some weird design decision made back in 1953 and has caused many, many guys to stab their distributor 180° out of phase. Resulting huge fireballs out the carb are spectacular but no fun.

tmoble

here's the same procedure written up for engines with poly-lock rocker nuts. usually any roller rocker uses these.

exhaust opening, adjust intake

intake closing, adjust exhaust

Well known since the 80s.

spinning the pushrod with fingers is just a way to find the zero lash point.

back off all your polylocks at least two full turns. back off the setscrew in each one at least two full turns. turn the engine with balancer bolt or remote starter switch till #1 exhaust just starts to open. judge this by eye, you can see it the pushrod move up. spin the intake nut down to zero lash, confirm by rattling the pushrod up and down and spinning until the play goes out. adjust the intake to 3/4 turn preload. run the setscrew down to lock, then give the nut another 1/16 turn to jam the setscrew firmly. go to number 8, turn the engine 1/4 turn, see the #8 exhaust pushrod start to move up, adjust the #8 intake as on #1. then turn the engine 1/4 turn, see the #4 exhaust pushrod start to come up, adjust the #4 intake as before. go thru the firing order 1-8-4-3-6-5-7-2. back to #1, turn the engine till the #1 intake valve goes to full open and starts to close, it will take like a full turn of the engine. adjust the #1 exhaust like all the others. turn the engine 1/4 turn, see the #8 intake go to full open and start to close. adjust the #8 exhaust as before. Give the engine 1/4 turn, see the #4 intake go full open and start to close. adjust the #4 exhaust as before. go the rest of the way through the firing order as before. Sanity check: when done all the nuts should be about the same height, all the setscrews should be about the same depth. If any are way off do that valve again. Incidentally, when the dots on the timing gears are together, 6:00 on the cam gear and 12:00 on the crank gear, the engine is at TDC on the firing stroke for #6 cylinder, not #1. This is due to some weird design decision made back in 1953 and has caused many, many guys to stab their distributor 180° out of phase. Resulting huge fireballs out the carb are spectacular but no fun.

If you have a solid lifter engine instead of setting the pre-load to 3/4 turn you'll adjust the lash using a feeler gauge. I use "Go - No Go" feelers, the tip is 2 thou thinner than the body. IOW, an .018 gauge is .017 on the tip and .019 on the body. if 17 goes in and 19 doesn't, close enough to 18. If you have roller rockers pull the gauge in from the side, not straight under the roller. this will normally result in the lash being a couple thou tight.