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[Brazilla]

If I can see something in there that moves when I crank the engine what could it be? Inlet valve had over tightened during a short run, connected? Thanks, a bit worried

[Norm]

piston? or top of piston seen that before, put a screwdriver on it and it drops down

[Beezabryan]

Piston crown, pistons have a hanit of moving up and down when the engine turns over

[Brazilla]

Yes, I suspected that until it moved side to side?

[Nettshubby]

Valve "overtightened"? Do you mean seized? Probably the head of valve snapped off and dropped onto piston? You don't say how big or what she the thing is. Has decompressor fallen apart and little valve dropped in. More info required!

[Nettshubby]

That should be what SIZE the thing is!

[Thack]

It's just the edge of the valve, surely. I've seen it myself. Nothing to worry about.



When you say "overtightened" I take it you mean you had the tappet set too tight? So long as you fixed it promptly, no harm will be done.

[Brazilla]

Yeah sorry I didn't put too much detail as am at work. It appeared running along one edge of the socket about a centimetre or so inside and then after cranking I noticed similar on the other side. That made me think it was the valves, just surprised I'd not seen before. Yeah, the tappets were ok when I set off but when I tried to put piston to tdc when I parked up, I realised there was no compression. When I checked tappets the inlet one had no movement at all! Hoping I'll get home ok!

[Thack]

Hey, Brazilia, can I persuade you to cancel your plans for this evening and fix that tight inlet valve before driving it home again?



It'll be inconvenient, but I wouldn't want to risk burning it.

[Presto]

Brazilla, are you talking about movementm or rather no movement, in the push-rod?
Be careful - there should be no movement UP or DOWN in the pushrod when adjusted correctly - but the push-rods should spin freely. And make sure the engine is cold and the piston is at TDC with both valves closed. (Or maybe I'm missing something )