Hydraulic lifter adjust

[Fred_M1010]

Aren't you just repositioning the piston in the lifter?

That was my conclusion as well, when I examined how my lifters worked...
But maybe I'm missing something

 

[mr250twostroke]

i dont know why you guys are questioning scott ( 4x4high ) since he built motors for years in his own shop and even a few for members here.

This is my thought as well. Scott's knowledge is vast as ALWAYS right in my personal experience with him.

 

[nsxxtreme]

Aren't you just repositioning the piston in the lifter?

I'm not sure what that means or what it infers. But the lifters fills up with oil. Liquid doesn't compress so the "piston" would be fully extended once oil got in there. So even though that "piston" goes down when you you tighten the valves it will go back up once it fills up with oil. So preloading the valves would be the end result.

 

[British Slave]

I'm not sure what that means or what it infers. But the lifters fills up with oil. Liquid doesn't compress so the "piston" would be fully extended once oil got in there. So even though that "piston" goes down when you you tighten the valves it will go back up once it fills up with oil. So preloading the valves would be the end result.

Depends on oil pressure vs spring pressure.

And that means and infers the amount of pressure provided by the oil pump and the amount of pressure applied by the springs when compressed.

 

[nsxxtreme]

Depends on oil pressure vs spring pressure.

And that means and infers the amount of pressure provided by the oil pump and the amount of pressure applied by the springs when compressed.

The comment made was that it would decrease higher RPM operation. Which infers the oil pressure would be high.

 

[Fred_M1010]

i dont know why you guys are questioning scott ( 4x4high ) since he built motors for years in his own shop and even a few for members here.

I can't see what's wrong with a good and sound debate.
And I doubt Scott has anything against that either.

As Albert Einstein once sad "the important thing is to never stop questioning things"

Because what you're doing is preloading the lifter and the more you preload it the less RPM you'll get before the valve starts to float.

I can't see how that could cause valve float.
IMHO Valve float is caused by too weak valve springs for the application.

But I can see how a lifter with more pre-load can cause more damage if you get valve float, since they can get pumped up more.
But maybe that was what you meant?

 

[British Slave]

The comment made was that it would decrease higher RPM operation. Which infers the oil pressure would be high.

I thought there was a relief spring in the oil pump to limit how high the oil pressure could get.....infered or not.

 

[nsxxtreme]

I thought there was a relief spring in the oil pump to limit how high the oil pressure could get.....infered or not.

I'm assuming these motors came with the HV, HP oil pump from the factory. Mine did. That's about 80 psi at 4k rpm. Not sure when it reaches 80 psi but I assume it occurs fairly quick in the rpms. Those lifters are going to fill up fast. Wether or not there is enough valve spring pressure to over come the oil pressure I don't know for sure. I'm no expert, but I suspect there is. If you push that piston down without the engine running then when it does run it's going to push the valve open more. And when the valve tries to close it wont go all the way down. Thus as the RPM's increase and you get more oil pressure in there the chances of floating a valve go up as the RPM's increase.

The lifters that I bought for my recent rebuild have relief valves in them. I've heard differing opinions on these also.