Austin (Rover) Metro (1980 - 1990) - 89 998cc jammed valve.

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Mon 20 May 2002 16:33
89 998cc jammed valve. - deltaseven
I have a 1989 Rover Metro 1l. I needed to replace the head gasket on it. That done, turning the engine over by hand (on the crankshaft), the engine turns almost a full revolution, but jams solid when it comes to closing no 5 valve. Also, the pushrod for no 5 does not rise as high as the other push-rods (even with the tappet open).

what could be causing this to jam?

Edited by Pugugly on 28/02/2008 at 20:34

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Mon 20 May 2002 17:29
Jammed valve on Metro 998cc - Richard Hall
I haven't a clue, but try the following:

Remove the valve rockers and pushrods, also the spark plugs. Rotate the engine by hand to 90 degrees before top dead centre, so the pistons are well clear of the head, and tap each valve sharply with a hammer, and check it returns fully to its seated position - this will eliminate sticking valves. Check none of the pushrods are bent or damaged from incorrect seating, and make sure all the valve rockers are free to move. Finally, without refitting the valve gear, try turning the engine by hand. If it still locks up, you have probably left an object (such as a nut) on top of one of the pistons when you put the head back on. If oil or water squirts from one of the plug holes, you have a hydraulic lock caused by fluids getting into the combustion chamber (did you refill the engine with coolant before you tried to turn it?) Either way it's off with the head again.
Richard Hall
bangernomics.tripod.com
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Mon 20 May 2002 19:52
Jammed valve on Metro 998cc - John S
deltaseven

My guess you displaced a cam follower (or tappet) out of its bore as you removed the push rods - easily done as the oil holds the push rod in the follower and when you pull them out you lift the cam follower too. It's probably come right out of its bore and dropped into the tappet chest. Seen it done more than once on an A-series engine.

Always give the push rods a twist and ensure they're free of the cam followers before pulling them out. With the cam follower out of the way, when you drop in the push rods it allows them to drop right onto, or more likely slightly to one side of the camshaft, and that's what's jamming the engine. This is also consistent with a reduced movement of the push rod.

Easy (well, relatively) to fix if the engine's got tappet chest covers - more tricky if it hasn't. You'll need to check the push rod is straight before reuse.

Regards

John S
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Tue 21 May 2002 12:22
Jammed valve on Metro 998cc - deltaseven
Thanks John,

That sounds like a very likely scenario. I will have a look tonight, and see where it gets me! Will update you tomorrow morning! d7
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Wed 22 May 2002 08:32
Jammed valve on Metro 998cc - deltaseven
Many thanks John - you've solved my problem! I opened the side covers last night, and there it was, tappet out of its bore!

She is now running sweetly again.
D7
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Wed 22 May 2002 08:42
Jammed valve on Metro 998cc - John S
d7

Excellent! Another success for the Backroom.

Regards

John S
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