Talk Morgan Forums Morgan Sports Cars Morgan Three Wheeler & Super 3 Valve Train Noise

This S&S engine has the noisiest valve train I can remember on any engine I've owned.

This amount of tapping would traditionally suggest that the gaps are too wide and that the rockers are hammering on the valves.

Has anyone ever done a dry clearance check to verify valve train lash?

No, but I have installed the roller rockers in an attempt to lessen the noise, especially for after a long run, The roller rockers do lessen the noise some or tend to deaden it somewhat due to the deadening effect of the AL. Also a side benefit is that they bump the rocker ratio somewhat and I (seem) to notice a slightly more crisp snap in performance.

+1

i was wondering is the engine still non contact if the cam belt goes with the roller rocker conversion (higher lift ratio) I would think of doing this mod if its still safe!

On some engines, if you fit roller rockers, you can decrease the gap slightly. No idea if that is true on the S&S.

Mind you, the tappet gap on the JAP LTOW is a whole 2 thou, and they are still noisy.

So the rattle cans are often left off.

The tuning parts list indicates with 569 cam (0.569" valve lift with stock rocker ratio of 1.76) the engine remains non-interference. Given that the stock 548 cam with roller conversion (1.8 rocker ratio) gives less valve lift (-8.5 thou) it seems reasonable to assume this combination will allow the engine to remain non-interference, especially as valve overlap is likely to be less with stock cam.

Good news thanks Richard..kit looks about 350 USD I prob get kit from Krazy Horse?

WOW a Whole 2 thou not much room for heat expansion!!!! stays cool out in the breeze i suppose .

I believe that running clearance is greater than that, but when cold you do set them very close. When warm the motor expands and the valve lash increases automatically.

As far as the valve noise on an S&S motor, the newer Harley Twin Cams have a very similar problem. The cam profile has a lot to do with the valve train noise. On some of the Harleys with S&S lifters, they over tighten the push rods to add more preload and this does help in some cases.

Typically roller rockers in automotive motors are noisier than non-roller rockers. S&S I believe uses GM V-8 rockers, cheaper to buy something that already works than to make their own.

Hi JamesB,

I used to run Mobile Synthetic 1 20w50 oil for VTwins in my M3W and also noticed a lot of engine and tappet sounds. Certainly this is an excellent oil. I tried Royal Purple Max-Cycle 20w50 synthetic oil and noticed a significant reduction of engine and tappet sounds from day 1. I've been very happy with this product and will be using it from now on.