350 Uneven Cranking & Won't Stay Running After Break In

[Baprace]

FWIW if at first assembly you went 3/4 turn after zero lash and the lifters pumped up fully then around.031” multiplied by rocker ratio was added to valve lift at all points.

Can you describe the type of clip that holds the lifter plunger ? is it a round wire type or does it have flat type with a hole on each end of the clip ?

[HQM383]

FWIW if at first assembly you went 3/4 turn after zero lash and the lifters pumped up fully then around.031” multiplied by rocker ratio was added to valve lift at all points.

Can you describe the type of clip that holds the lifter plunger ? is it a round wire type or does it have flat type with a hole on each end of the clip ?

Question for the O/P?

[EXCELLENCE AUTO]

Man, I'm glad you got this running!

[1980RS]

SHE'S ALIVE!

I did the Ellison valve adjustment method. It was pretty simple to do, don't have to keep track of your positioning and whatnot. Once they were all at zero lash, I gave it 3/4 turn like he recommended.

NOPE! Too much. I'd say it was worse than before! So I backed them each up 3/4 turn and got them back to roughly zero lash. Pumped the gas a couple times, hit the ignition, and she started right up. They're definitely still on the loose side, as they are noisy. It's interesting - I gave them 1/2 turn on the engine stand (with no oil in lifters) and that was good for break in, minus the few that got loose on me. Then I did 1/4 turn, and that was still hanging a valve open. The Ellison method above with 3/4 turn was obviously too much, and zero lash is of course too little. 1/8 turn maybe?! Weird.

I think my best bet might be to cut up one of these old vortec valve covers and just adjust them while it's running. Either that or I'll have to keep trying different amounts of preload and see what it does.

I'm pretty sure I found the reason for it idling high as well. I sprayed some carb cleaner around my carb gasket, and the idle dropped. I reused the gasket, which I've had success with before, but I guess it's time for a new one.

Next up is getting the valves adjusted right so I can at least move the car and run it without worrying. Then I can dial in the timing and see if I can get the double pumper running happily. Then I'll take it for a quick drive to make sure the rings seal up, then change out the break in oil. After that I'll have to start thinking about the heads. All the comments about the lift has me a bit worried.. I definitely beat the piss out of this car.

Just wanted to again thank everyone for thinking this one out with me. I appreciate you guys a bunch.

Congrats on getting the engine running right. On Hyd cams I only use 0 lash plus 1/8 turn down as almost every Hyd cam I ever ran with most lifters at 3/4 turn down went into lifter pump up at high RPM. Not sure how my BBC will be next year with my Hyd roller cam, might have to experiment with those a little.

[Tom68]

Congrats on getting the engine running right. On Hyd cams I only use 0 lash plus 1/8 turn down as almost every Hyd cam I ever ran with most lifters at 3/4 turn down went into lifter pump up at high RPM. Not sure how my BBC will be next year with my Hyd roller cam, might have to experiment with those a little.

Yer I think Evil had trouble setting dry lifters with feel between resting on the plunger and collapsing the lifter, pays to do it before the manifold goes on if you don't have the feel for it yet.

[cgarb]

I think you have some lifters that are bleeding down. Some you are setting correctly with preload and the ones that are bleeding down you are already at the bottom of the travel and putting your 1/4 or half turn there and it's holding those valves open. I don't mess with hydraulic cam and lifters a whole lot. I drag race and use all solid or solid roller stuff. The last SBF 302 I had that was hydraulic I used to roll the motor over by hand till the cam was on the base circle of that valve. Then I would tighten the poly lock until I could just feel no wiggle of the pushrod. That was zero lash. I only would do 1/8 to 1/4 turn preload. I only ran that cam one year and next time I had the engine apart I swapped to a solid lift Reed camshaft.

[FishFry]

It's interesting - I gave them 1/2 turn on the engine stand (with no oil in lifters) and that was good for break in

You just answered your own question.
The Ellison method requires dry lifters - you just did it with wet lifters (pumped up - and maybe some of the are already bleeding down a bit while you are working at them), so there is no more 3/4 turn to compensate.
A quarter or half turn should be more than enough.

Frank

[rebelyell]

Watch Ellisons Machine Shop YouTube video on valve adjustment and follow his procedure exactly. Hopefully you were just a little out of adjustment on the 3 loose rockers. Good luck!

IIRC, ellisons method begins with Dry, Empty lifters.
perhaps, pull all 16, carefully disassemble (do NOT mix parts between lifters), thoroughly clean all bits w/ brake or carb cleaner, reassemble with only kerosene or wd40 or similar light lube internally.

[evilws666]

I think you have some lifters that are bleeding down. Some you are setting correctly with preload and the ones that are bleeding down you are already at the bottom of the travel and putting your 1/4 or half turn there and it's holding those valves open. I don't mess with hydraulic cam and lifters a whole lot. I drag race and use all solid or solid roller stuff. The last SBF 302 I had that was hydraulic I used to roll the motor over by hand till the cam was on the base circle of that valve. Then I would tighten the poly lock until I could just feel no wiggle of the pushrod. That was zero lash. I only would do 1/8 to 1/4 turn preload. I only ran that cam one year and next time I had the engine apart I swapped to a solid lift Reed camshaft.

I think this is what's happening too. Either that or one (or more) lifters collapsed which is basically causing the same issue when i am adjusting the valves. It's been a few days since I've been out in the garage, but I am going to adjust them all again, and see if I can pinpoint any suspect lifters.