Cam followers.
Frans, did you reface them? How?
Frans, did you reface them? How?
807 Competition motor.
- Thread starter Frans
- Start date
Did you harden them before engine assembly or relied on your run-in method?
Hi, the followers do have their own hardened part, often visible as a flat piece that looks like it has been silver soldered or sweated on and that is about 1mm thick. good enough for a few re-surfaces.
All the work hardening and running in is for the camshaft. It is just a cast iron item. There are billet cams that can be hard surfaced but not so much on the cast iron cams.
Frans
All the work hardening and running in is for the camshaft. It is just a cast iron item. There are billet cams that can be hard surfaced but not so much on the cast iron cams.
Frans
Hmmm. I am not so sure. Mine look like they don't have anything, or maybe my eyes don't see it.
Anyway.
What do you do about tappets? These need refacing and are cast steel, and I am pretty sure they need hardening too.
How do you harden these?
Anyway.
What do you do about tappets? These need refacing and are cast steel, and I am pretty sure they need hardening too.
How do you harden these?
Hi SZ,
If you look at post 34 on P2 you will see what I mean on picture 3 and 5. The hardened part is clearly visible as an extra disc and it is a decent thickness. But I can also see the following one that was sand blasted is not visible. I think you don't need to worry about it, it will have the hard part in it.
With tappets I take it you mean rockers? I do that on a fine stone grinding wheel and remove just enough to get it "clean". They are either hardened or will work harden the same as the cam. I'm not sure about them but "so far so good".
If you look at post 34 on P2 you will see what I mean on picture 3 and 5. The hardened part is clearly visible as an extra disc and it is a decent thickness. But I can also see the following one that was sand blasted is not visible. I think you don't need to worry about it, it will have the hard part in it.
With tappets I take it you mean rockers? I do that on a fine stone grinding wheel and remove just enough to get it "clean". They are either hardened or will work harden the same as the cam. I'm not sure about them but "so far so good".
Yeah, you're right. Tired last night when wrote that one, I meant rockers.
Well, if you have a chance next time you have a look at the innards of your engine, would be interesting to see what's goin' on.
What I found on the old ones I am looking at here is a number of patterns of wear.
One pattern is where they developed flat surfaces at different angles on the rounded surface that pushes against the valve end. These are parallel surfaces with a common side, running across the face (or parallel to the rocker shaft as one would expect). These can be either two or three surfaces about 1mm wide, and look like they are either seriously work hardened or seriously worn (very shiny - mirror like).
Another wear pattern is a circular "scar" like an indentation left by the valve end in the rocker face. These rockers look like they pushed against the valve stem side, as if the rocker arm was too short, and when it reached the end of travel (full valve opening) was pushing on the very side of the valve stem. There are distinct round contours of the valve stem end imprinted in the rocker face. The circular imprint is also pitted. Or maybe the cast steel was porous and the wear uncovered the little pores just under the surface (poor QA/QC from Renault?).
Well, if you have a chance next time you have a look at the innards of your engine, would be interesting to see what's goin' on.
What I found on the old ones I am looking at here is a number of patterns of wear.
One pattern is where they developed flat surfaces at different angles on the rounded surface that pushes against the valve end. These are parallel surfaces with a common side, running across the face (or parallel to the rocker shaft as one would expect). These can be either two or three surfaces about 1mm wide, and look like they are either seriously work hardened or seriously worn (very shiny - mirror like).
Another wear pattern is a circular "scar" like an indentation left by the valve end in the rocker face. These rockers look like they pushed against the valve stem side, as if the rocker arm was too short, and when it reached the end of travel (full valve opening) was pushing on the very side of the valve stem. There are distinct round contours of the valve stem end imprinted in the rocker face. The circular imprint is also pitted. Or maybe the cast steel was porous and the wear uncovered the little pores just under the surface (poor QA/QC from Renault?).
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