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[Mark2]

Hi Simon and all,

Continuing on from my post of 20th August, i am trying to identify an engine rattle. I stripped the head down where the noise seemed the strongest. the valve adjustment was fine and in the end nothing was amiss,i replaced the valve end caps as one of these did seem to have a bit of wear but nothing major. Unfortunately engine still rattled once warmed up,so can only presume the problem lies even deeper. I like the idea of waiting till a failure occurs,at least you can tell what you are looking for, but I cannot stand the damned noise. Listening to the music from below is one of the major plusses to riding the bike. I shall have to start singing to cover it up.

[simon]

Yes it's a weird business. Does yours rattle continuously or is it like mine an occasional occurrence?

[Norm]

Has to be a loose valve seat

[Mark2]

engine starts to rattle after about one mile once warm. Seems loudest when on a neutral throttle and the bike is just running along. Doesnt seem so bad when you gather speed but it might be masked by the increase in noise. how do you check for a loose valve seat and what can you do about it norm ?

[Chris Tindal]

Mark are you sure its not just the normal rattle these engines make? Have you compared it to others? They seem to vary in noise level but they are generally fairly clattery anyway. Mine sounds like a cement mixer compared to my mates but everything seems to be in order so I just ride it.

[m1ks]

Have you used a sounding stick to verify the exact location of the noise? Assuming it rattles at idle, if you get it warm then use a long screwdriver or long length of dowel with one end firmly on the little cartlidge flap on your ear use the other to wedge firmly against each portion of the engine in turn, (much like a stethoscope).
It's amazing the way it clarifies the location of sounds.

[simon]

The valve seat idea of Norm's has enormous intellectual appeal but sadly I have proved at some considerable expense that it isn't the issue. With mine at any rate. My rattle will start after a short fast run and park up and then another run. Almost as if something has got hot but not everything. This fitted valve seats perfectly but sadly whilst I have a beautifully reconditioned head the rattle (every few weeks) persists. My feeling is the noise is definitely valve train related though and I'm wondering if it could be the pushrod ends coming unstuck. The only issue with this is the fact that the idle is perfect despite the clatter. Another thought is that its something to do with the followers but I have to work on that theory.

[Mark2]

Hi all,

Yes I have used the screwdriver trick for listening to the engine,exhaust valve area noisy,inlet valve area not so bad, cylinder, not so bad.Even had the exhaust valve cover off with the engine running, all seems to be in order. You cant influence the noise at all with a screwdriver held on various components.

im not saying simons problem is the same as my problem which is there everytime the engine is warmed up just that if you listen to his video then it seems similar. I know these motors are noisy but this has appeared only in the last few weeks.It seems strange that nobody else is reporting a lot of excessive noise, but then I do not know anybody else with an enfield so cant make comparisons.

Regards Mark

[Norm]

Hi Simon, loose seat may not be your problem but loose seats are something that occurs with Enfields. As for loose pushrod ends I doubt it because the ends should basicly remain under tension unless the tappets were loose enough to allow the ends to move, but nothing is beyond possibility

[fjr]

I do think it could be the rocker blocks expanding with the heat of a hot engine. My 98 500 starts off with no rattles but after 10- 15 miles it has a top end rattle. I think this causes an increased valve clearance, hence the rattle.Oil supply to the rockers is still in good supply,tappet clearance is right when cold.