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Hi All, Just after a little help, Tried looking at the parts picture but I am not sure if a 38 110 engine should have valve shims under the valve springs. I have a partially dismantled engine which I am trying to rebuild and can tell that the work that has been carried out on it over the years hasn,t been that great. I have some valve shims but not 12 so I am not sure if some valves have been shimmed over the years and some haven't, or maybe some shims have been lost over the years. Does anyone know?. Many Thanks Allan

Dear Allen:

Nothing is listed in the parts book and I don't recall those motors having spacers.

If they are flat washer like shims, that means the motor has been rebuilt by a professional who used those spacers to set the installed height of the valve springs.

You can check the thickness of the shims and use a straightedge across the motor to figure out which valve springs need a shame. Valves that are low in the motor will need a shim to compensate for reduced spring tension.

I am not an engine rebuilder so I don't know much BUT the following is a quote from my shop manual.

"NOTE: Serrated washer at the top end of each valve spring is to prevent valve rotation. Make sure that top of spring and serrated washer are fully seated in counterbored recess in cylinder block."

Maybe someone can expand more fully on this.

As Tim said, some engine rebuilders might have used shims to compensate for out-of-spec valve springs though a far better route would have been to replace questionable (or all) valve springs. But yes, the upper end of the spring should be separated from the block by a serrated washer to prevent rotation of the assembly. That said, there are engines designed for valve rotation by use of something like a "rotocap", but not applicable in this case.

Thanks for that, I had another look today and the shims are not serrated. They are very nicely machined (look factory) and are over 100 thou thick.I,ll buy a new set of springs and when I set the up the valves, I,ll check spring pressures at the installed height on the old springs and new springs to see if the thick shims are needed or I can just use a normal type of valve shim.