Is There A "Good Way" To Set Lashing? 350

Hello all. I'm having some trouble with a noisy valvetrain on a Buick 350. I bought the engine "rebuilt." It was my family's first Buick V8 and little-did-I-know the lifters were shot, the pushrods were all wrong, and it destroyed the camshaft. I now have a TA cam (specs can be provided), new Crane lifters, new rocker assemblies, and adjustable pushrods from TA. Is there a tried-and-true way to set up those pushrods? I've made 3 attempts and my best so far was to lengthen them until I can no longer wiggle the pushrod up and down, and then add a full turn. Am I close? Am I missing a step? I really don't want to ruin another camshaft and I'm afraid to go racing.

 

You should be able to use stock length pushrods and just tighten down the rocker bar. Did you do a proper cam break in on Int start up?

 

go 1/2 turn

 

If you have stock pushrods go back to them. I never had luck with adjustables. I did them with engine running and loaded them up after noise stopped. That's the best I had them. Never true them again.

 

Yes, the cam did receive the proper break-in procedure. That was last summer.
We did try a full set of stock length pushrods, but the problem (we believe) is that the valves weren't all seated at the same height. So with the stock length rods and the rocker shafts torqued to spec we still had a rattle. (Come to think of it, that was before the cam change...) So far the adjustable pushrods have gotten the engine the closest to "quiet" it's ever been.
I'm probably going to try giving them another 1/2 turn and see where that gets me.

 

The easiest way is to adjust them one by one. Attached is the procedure that I find easiest and just ignore the part about measuring the adjustable said your not planning to swap them for solid versions. Gary P wrote it:

 

If the valves are not all the same or very close its going to be trial and error.

 

what if the cam has a reduced or different base circled compared to the previous cam? best bet is to use an adjustable to set preload and then remove it to compare to stock.

 

He has adjustables so all he needs to do is follow that set of instructions I posted above.

 

Thank you. I'll try this. I had been using a Chevy hydraulic lifter method with the crank on the basis that they share the same firing order, doing half of the pushrods on TDC (for the valves specifically listed to do in that position) and then the other half after turning the crank 360 degrees.

 

That is exactly how you should do them. Start with #1 on TDC, go through the loose ones, make a revolution of the crank back to 0 on timing mark, go through loose ones, then 2 more revolutions and you should have all of them done, but again, it takes 4 full turns to go through all of them. I zero lashed mine, then gave each adjustable pushrod a 1/4 turn more for preload.

 

Well, I finally took a crack at this. I did one cylinder at a time. It still isn't as quiet as I expected, but then again I don't know Buick engines too well and it's actually running very well now.

 

TA adjustables have 1/4 -32 UNEF thread, so one full turn is .031", 1/2 turn is .016" and 3/4 turn (my personal choice) is .023" preload.

 

6 years later, I found out that I had a lifter not spinning. It was on the driver's side, just like the 2 lobe failures I had on my first camshaft.

 

The trick is to put cam and lifters dry and spin the cam to see which lifters are not spinning and change them to different holes to see if they spin. Some lifters took 14 revolutions of the cam to make a revolution some would do it in 7-10 I keep moving them around to get the most out of all of them. Mine made noise for 25 years I just figure it is the nature of the beast.

 

Hey Fox,
Let me get this straight. I can just put my camshaft in the engine, put the lifters in, dry, and spin the camshaft and the lifters should spin? Very cool

 

Yes assemble dry and rotate the engine by hand. If a lifter doesn’t spin then some people machine then face of the lifter. Personally I just bought another set of lifters and swapped out the ones that didn’t spin.

https://www.motortrend.com/how-to/check-flat-tappet-lifter-crown-lobe-taper-lifter-bores/amp/

 

So you just keep buying new lifters until you get the rest to spin? Why would you machine a new face on a new lifter to get it to spin? Or would you just sent the whole group of lifters back and get a new set?
Yes that is the way I read it, put in dry and see which ones do not spin. The article Sean put up said to put downward pressure on a pushrod, I did not do this, since it was on the dry side with very little oil. After I was done I numbered the lifters, wiped with lightly oiled towel and put them back into the box until I was ready to put in.

I do have the Howards lifters and they have the taper on the lobes, going to try and see if I can get a reading off the cam.
When I started to Put together the parts 3 years ago money was real tight, not working a lot either, did what I had to do to make the change. Right now, this all bothers me about putting in a flat tappet cam and hoping it survives.
I didn't think it was going to take this long but it is, parts were a lot more expensive. This should not be hard and scary to start up but seems to be that way with flat tappets. I think if I was doing this today I would just bite the bullit and get the roller cam.

But it would be a solid roller cam if you are going to spin it to 7 grand, might as well make sure it can get there why screw around.

 

I would inspect each lifter bore for nicks, burrs, upsets, etc. That could cause interference and hinder the lifter to spin freely.