Hot Rods Solid lifters, what causes them to need to be adjusted all the time?

I have a cam I dearly love in my attic. It's an old vintage grind from Engle. It's an Engle 95 for a 283/327. It's mild by todays standards, but it has a great power range and it sounds great in a short stroke small block. I ran it in my 283 in high school. It's perfect for a period correct 3x2 327 with double hump heads.

I was wondering why solids require lash adjustments all the time? Is it the rocker arm nuts? If I ran a modern style poly lock, would that help eliminate the constant need to adjust?

I'm getting lazy in my old age.

 

On Chevies that was the biggest problem, lock nuts should help. Also the larger the clearances the more problem you will have.




Bones

 

how often are you adjusting them? what makes you think that they need to be adjusted often?

 

More than hydraulics.....

 

Hydraulics never need to be adjusted, once the preload is set. Solids...just to make up for wear. But they should settle in after a little while, and not need adjusting often. If they keep needing adjustment somethings wrong.

 

I have solids in 3 of my cars, all sbc's I check em when I tune em up , usually nothing too far outa wack.

 

Whoops..4 cars , the 57 has a solid roller.

 

Everytime you move a stock nut on a lifter stud, I gets a little looser. It depends on how many times the nut had been run up and down the stud. Back when I was building Chevy race engines we had some heads that had been used quite a bit and we had trouble keeping the cam lash set until we got some of those long nuts with a set screw in the top of them. On my OT 289/271 Hp car , I only adjusted them twice in 100,000 miles.Just my experiences.



Bones

 

Back in those days the rocker studs were pressed in. It was standard practice to install screw-in studs if you could afford it; if not, then they sold rocker stud pinning kits. If you had to make constant adjustments something was moving, nuts, studs or the cam was wearing excessively. I had several sbc with solids but they all had pinned or screw-in studs and Poly-locks. BTW; remember the first gen screw-in studs, they had no hex, they looked just like hardware store studs.
You should have better luck today with better valve train parts.

 

Always use screw in studs with a hi po cam I can actually remember fools back in the day pulling valve covers and hammering their studs back in cause they were pulling out of the heads

 

That’s what I was thinking. Everyone says they need adjusting every 1500 miles. I just have to wonder where the material is going if the lash is changing that much? I ran this cam in the 80’s and I don’t remember adjusting them that much, but I was a kid and had nothing but time.

My solid roller is always spot on when I check it, but it never sees a lot of mileage. Just 1/4 mile at a time....

This cam was probably ground in the early 60’s.

 

As Jim has said- always a myth to solids....... This is/would be if your racing/revving the piss out of it, and just checking/piece of mind. Weren't we all tought that? Myth Busters......
Yes!= Things move around, loosen up, etc........ On the street= Not so much, but periodical maintenance should be performed, never hurts to run lash from time to time...... If they're coming loose, there's other issues...... Run it, maintain it, rumpity rump it..... Cams/rockers/ locks, have come a long way...... Set up correctly, there should be no issues......

 

Also normal wear will see the exhaust valve pounding the valve seat moving the valve HIGHER in the head decreasing the clearance.

 

You'll never completely eliminate the need for valve adjustments, at best you can extend the interval. There's too many wear points, and while any one of them may not show enough wear to make adjustment necessary often, add them together and you can get meaningful differences in valve lash.

The most wear IMO is at the valve/seat. That's the one unlubricated spot in your valvetrain and can be more than you think. There can be considerable wear without degrading the sealing. As an example, I mess around with DOHC motorcycles that use shim/bucket adjustment. There's only three wear points; the cam, the shim, and the valve/seat. On these the valves tighten as things wear, not loosen, all due to valve/seat wear from what I've seen. I have yet to find a shim with measurable wear. The particular bikes I do I usually pick up for cheap because the owner has failed to do needed maintenance and they've either quit running or are running poorly. The last one I bought had compression readings of between 15 and 90 lbs across the four cylinders, which would lead you to believe the motor would need major work. After just a valve adjustment, I got 180-190 across the four. And as was pointed out above, the exhaust valves were the ones the most out of adjustment.

The factory valve adjustment interval is 12K miles, from what I could tell the one above had probably been run to about 40K to get as bad as it was.

 

It’s really small by today’s standards. I would guess it is in the range of a 300 hp 327 cam. Maybe a .440” lift adv and maybe a 260 degree duration. I just pondered throwing a 1.6 rocker on it and running it for nostalgia sake in my 327 I have on the stand. I have 2 or 3 new cams in the boxes on the shelf in multiple grinds.

 

do you have the lifters that ran with it? or would you be using new lifters?

 

I would have to use new lifters.

 

In the 70's I was running a SBC in a dirt track modified. Solid flat tappet cam and roller rockers with the long nuts and set screw locks. Some, not all valves would be out .005 to .009 at the end of each race day, not the same ones all the time. Someone suggested a stud girdle and that stopped it. Check them at mid and end of season and had no movement. Must have been the studs flexing enough to stretch a little. Never broke any.

 

My 57 Fuely had the 097 solid cam. Ran it a good bit but seldom had to adjust valves-stock nuts (new) pinned studs. A couple would need a touch of adjustment if really I leaned on it alot--other wise not much at all with normal driving.

 

^ ^^^^^^^

 

So I'm not the only one who was under the impression that solid lifters require a "lot" more adjustment. No experience with them...just stuff I've heard over the years...apparently the wrong stuff. Good to know. Still, I always thought that if I wanted to someday run solids, I'd live with the necessary maintenance requirements.
Thanks for bringing it up, Roothawg.

 

A properly designed, properly maintained engine with solid lifters should need adjusting no more than every 20,000 miles or so. Even then you should find all except 2 or 3 valves very close. In other words, you shouldn't need to adjust them all even after 20,000 miles.

The exception was old air cooled VWs. They recommended valve adjustments every 4000 miles and usually 2 or 3 needed adjustment, especially #3 cylinder which ran hotter than the others.

Apparently 'properly designed' lets Chevrolet out. If others in this thread are correct they need some mods to the valve adjusting mechanism if you want them to hold their adjustment.

On the good side if you do the valve adjustments as you should the valve gear will remain quiet for the life of the engine. I had a slant six Dodge pickup with 160,000 miles on it and you could not hear the engine run with the hood closed. This is the only quiet slant six I ever owned, and the only one that had been maintained by the book. You could tell the truck worked hard on the farm, but that the owner never neglected maintenance.

I have never seen a hydraulic lifter pushrod engine that did not get noisy after 100,000 miles or so.

 

Seats not wide enough. Some mechanics and machine shops ground them too narrow for a variety of reasons, but the end result is pitting, rapid wear, and valve burning if not kept in adjustment.

 

think of us poor flathead guys; ya gotta remove the intake to adjust lifters (providing they ARE the adjustable type). mom always used to say, "here comes a ford-- i can hear the tappets!"

 

shoulda got a Caddy flathead...hydraulic lifters! and they are spectacular to work on.

I guess it used to be that way, but modern cars don't seem to have that problem.

 

Thinking back to the 327 in my 57 Panel and the 283 that was in my T and then in my 48 I'd have to say that Bones and Bchtcybob pretty well hit the issues with my engines on the head in posts 9 & 10 Old heads with pressed in studs and old nuts that when used with solid lifter cams managed to get out of adjustment a lot more often than the norm for other engines with solids. The 327 was allegedly a fresh build when I bought the panel and the hottest engine power wise I have ever owned before or since runniing 12.5 pistons, 202 heads and an Engle cam with a Corvette intake with 2 4 barrels. . The 283 ran and old 30-30 cam and power pack heads and wasn't too fancy. I ended up adjusting the valves in either of them at least once a month.

 

I always wondered about that myself. I never had a hot rod with solid lifters. Some guys with them seemed to be adjusting them every week. Some seldom had a problem. My only experience with solid lifters is in slant six Mopars. A lot were never adjusted in the life of the engine.

 

I ran solids on my big block in a stock car with an L88 cam. It had screw in studs, poly-locks. I recall checking them after 3 races, made a minor adjustment. Checked them a month later and it wasn't worth the effort to adjust.

 

This particular cam has been in multiple engines. Never had a problem as long as I used new lifters. This is more of a question on where the increased lash comes from, rather than a should I run and old cam post. If that makes sense...