sloper valves

[chapmast]

I didn't realise that they were called lash caps and have managed to find a few that will fit 3/8 valves online. Unfortunately they seem to be mainly in the US or Australia.

I made a couple this morning and will probably also try some silver steel.

If valve caps aren't used then the difference in rocker angle is 3.6 degrees, but this is in the direction of the compression so it should be Ok -the Sloper isn't a precision instrument after all. I intend to try using valve caps anyway though.

In terms of the spring compression then it should only become a problem if the elastic limits are exceeded. So with respect to an extension spring you can keep pulling it apart and if you don't pull it too far then its fine. But if you pull it only once over it elastic limit then its permanently deformed.

I put some old A10 springs in a vice this morning and fully compressed them. They then sprang back to exactly the same length. If you watch the valves open and close on the Sloper then they don't descend very far and are no where near fully compressed. So there really shouldn't be a problem. At the end of the day the springs will weaken over time and to put things in context, then when the Sloper stops one of the valve is always left open. Hence the machine will have a set of Springs fully compressed for a relatively long period of time. When I restored my Sloper the exhaust valve springs were much shorter than the inlet, because it had been left with the exhaust valve open.

[craigc11g]

unlikely to make a difference , the valve maybe lighter , the distance you state would be about 3 too 5lb higher fitted so should not damage the valve train

[Mike Farmer]

 

Gotta say that info about the springs is very valuable and certainly puts my mind at rest to a large degree.
Thanks

Mike

[craigc11g]

if you send me the spring i can tell you exactly the lb it is when fitted and when open if you know the lift , this is not a hi reving motor and the lighter the valve train the easier on the motor , some valve springs are far to hi for the weight of the valve and expected rpm  , its just wasting power and waring cams .

[Mike Farmer]

 

Thanks for the offer but I reckon we just about covered this one. My only concern was the fact that with the shorter valve stems the springs would already be compressed by 1/10th inch then they are further compressed by the cam/rocker action which might make them harder work for the rocker arms etc.

Mike

[craigc11g]

as long as they do not go to near spring bound it will be ok

[Mike Farmer]

 

Thanks again. I understand what you mean.  Must confess the jury is still out on this one and in all honesty the cost of new valves is not a great addition when taking into account the overall cost of a complete engine rebuild. We'll see.

I'm having difficulty making a decision on this one.

Mike