Elio Engine Valvetrain

[Dustoff]

The point is very simple. Having someone cobble a description of the operation of hydraulic cam followers and present it under the letterhead of an Elio tech talk is confusing to say the least. Like everyone else here I am trying to gather information from this and other forums.I have read in several different places that classed shims are used. I've also read that hydraulic cam followers are used (which makes more sense even though more expensive). Just trying to get answers.

There is a rendition of the valve train. There is an explanation of the workings of a hydraulic valve. There is a conclusion.
It was presented to dispel the rumor of shims, which would be rather difficult to work with.
If you have any knowledge that the valves will be anything other than hydraulic, then please share.

 

[ThreeWheelBurnin]

Remember that era well. Some really bad quality control back then especially the late 70's and early 80's. Here is an example of some of General Motors work back then.

I need to stop looking at that picture. It's giving me a headache!

 

[zelio]

I need to stop looking at that picture. It's giving me a headache!

Is it for real or is it photoshopped because it is having the exact same affect on me! LOL :-) Z

 

[BlioKart]

Ahem. It wasn't the engineers that made that decision. It was the bean counters who are to blame. Engineers know separate functions should be on separate fuses. Bean counters only care that the extra fuse costs $0.10 more.

If you were driving any Malaise Era GM vehicle (1970-2000, roughly), it was designed almost entirely by the bean counters who utterly destroyed GM.

There is some irony that I've committed to buying a vehicle that it focusing heavily on reducing cost, with the head of sales even relating a story of how Mr. E. was walking around the P4 and pointing to places where they could save another dollar or two.

It is Ironic but in the end I know the Elio will not be perfect. I just hope it isn't a complete engineering mess. I think little issues get fixed by the aftermarket or by the manufacturer in newer model years. One main reason I always take manual transmission cars. 1 less thing to go wrong.

 

[Terrence]

Hoorah for hydraulic valve lifters within the Elio motor! Excellent design feature. :-)
Terrence Bernard

 

[ArthurKent]

Use you heads , people. Paul Elio's principle guiding light is low costs - low fuel costs, low initial price,
low maintenance costs. That rules out mechanical lifters (cam followers) Period. No one designing
a car like this woud EVER allow mechanical lifters into their engine. That would be insane.

 

[skygazer6033]

With the design of the valve train used in the IAV /Elio engine the simplest method of adjusting valve clearance is by use of hardened steel shims classed in different thicknesses. They're about the size of a nickel and fit into a recess in the cam follower bucket. If some provision is made to access the cam lobes with a feeler gauge then it's simple replace shims as needed to obtain proper clearance. Very simple, very reliable, very inexpensive. Hydraulic cam followers on the other hand are more expensive and may require a larger oil pump and oil passages. Another consideration is this type of engine usually have no cam bearings with the cam running directly on the head and caps. This in turn usually means a high volume oil system operating at lower pressure.

Use you heads , people. Paul Elio's principle guiding light is low costs - low fuel costs, low initial price,
low maintenance costs. That rules out mechanical lifters (cam followers) Period. No one designing
a car like this woud EVER allow mechanical lifters into their engine. That would be insane.

 

[CheeseheadEarl]

With the design of the valve train used in the IAV /Elio engine the simplest method of adjusting valve clearance is by use of hardened steel shims classed in different thicknesses. They're about the size of a nickel and fit into a recess in the cam follower bucket. If some provision is made to access the cam lobes with a feeler gauge then it's simple replace shims as needed to obtain proper clearance. Very simple, very reliable, very inexpensive. Hydraulic cam followers on the other hand are more expensive and may require a larger oil pump and oil passages. Another consideration is this type of engine usually have no cam bearings with the cam running directly on the head and caps. This in turn usually means a high volume oil system operating at lower pressure.

Shimmed solid lifters may be a cheaper "shelf" price, but the cost is in assembly/maintenance. Hydraulics are a drop in item.

There's no effing way that an aluminum block and head will run a bearingless cam either.

 

[skygazer6033]

Shimmed solid lifters may be a cheaper "shelf" price, but the cost is in assembly/maintenance. Hydraulics are a drop in item.

There's no effing way that an aluminum block and head will run a bearingless cam either.

I have worked with aluminum overcam engines for 30 or 40 years and I've never seen a cam bearing. All Honda engines(car and motorcycle) have cams that ride directly in the heads so does Mitsubishi, Acura, Cadillac Yamaha Suzuki and I'm sure many others (these are from my personal experience)

 

[CheeseheadEarl]

So you're telling me that the forged steel cam rotates directly against the cast aluminum block and head?

I'm finding this hard to believe.