Stuck tappet - how do I get it out?

[johnsimister]

A weird thing has happened to my engine. During a run last week I heard a sound as of a loose nut crashing around the cam cover as I slowed down for a junction. It was worst at idle and seemed to disappear at around 2000rpm, so I drove the couple of miles home very gently.

Off with the cam cover to find that number four inlet tappet is sticking. The rattle was caused by the massively increased tappet clearance, and possibly (though I hope not) the valve touching the piston. The tappet can move down further to open the valve fully, but doesn't return all the way up. It's impossble to rotate it, which makes me think the tappet is somehow snagging in its bore. If a valve spring had broken or the valve had bent, the tappet would turn.

I wondered at first if the shim had become displaced, then somehow got trapped between valve spring and the inside of the tappet's sides, but I don't see how that could happen given a) the generous depth of the recess in the valve cap in which the shim sits and b) the closeness of the valve spring to the inside of the tappet. The clearance had been slightly wide on that valve but only by a couple of thou, and the valvegear was quiet.

Does anyone have any ideas as to why this has happened? And, more pressingly, how I can extract the tappet? I've had thoughts of trying to drill and tap holes in the tappet so I can screw in a small bolt or two as something to pull against, but I suspect the tappet might be too hard. And if the tappet has partially seized for whatever reason, then maybe its bore is damaged and the head will have to come off and go to a specialist.

It was running so well, too...

John

[RichardS]

John

During a run last week ....It was running so well, too...
John

Were you making the run in the wake of the Europa SE as proposed in your Evo article??!! Atmospheric piece which I enjoyed reading last night.

I'm afraid my engine knowledge is very limited so my reply is of absolutely no help to your question but I am sure someone will have the answer!

Richard

[elan_fan]

have you removed the cam to try and remove the follower or does it not come back up it's bore after you rotate the cam?

The top of the cam bore is recessed at both sides to allow the rotation of the lobe, you normally extract the follower using a valve sucker tool. You can obviously grab at the offending item (but risk damaging it) if it comes past the recesses.

pics would be good

regards
Mark

[Tonyw]

John,

Those tappits are hardened steeel and will not drill readily if at all. If you have a bent valve that may prevent the tappit from returning, I am thinking that you will need to remove the cam shaft and see if you can get some compressed air down the side of the tappit and see if you can get it to raise up, try cleaning the tappit top off and use a valve lapping tool to see if you can get it to turn a little, if so use some solvent, wash it out and dry it with compressed air to try and free it up some more.

If you cannot move it in a passive sort of way you may have to resort to using a Dremel and cut some grooves in it to either tap it around with a small chisel or cut a hole in it so you can get a tool inside to pry it out.

I would not like to do this kind of surgery while the head was on the engine.

Tony W

[neilsjuke]

Strong magnet

[GrUmPyBoDgEr]

Surely this is a head off job in any case, in which case the tappet can be forced out using a drift through the valve guide.
The amount of wear described more than suggests the need for a general cylinder head overhaul.
More than likely the piston will need replacing which would mean a bottom end rebuild to boot.
A new water pump should also not be forgotten.
Sorry if that's what you didn't want to hear but to risk running the engine with that amount of wear is bound to lead to a catastrophic (read here, even more expensive) failure in the near future.

Good luck
John

[johnsimister]

Almost no wear in the engine. It was rebuilt about 3000 miles ago, sat for many years after initial use, was then in use again before I bought it. The water pump gave up recently due, I think, to water seeping past the seal while the car was laid up, so I've had the head off to replace the pump. Inside were clean pistons (new Omega) and fresh honing marks on the cylinders. The camshafts were new at rebuild time, the PO says they're Cosworth L2.

I'm thinking head off and over to a specialist. I'd have taken it to QED but they don't do rebuild work any more. Any recommendations? I'm in Herts so the nearer the better, but ultimately distance is much less important than getting the right people to resurrect the head.

John

[curly type 26]

Hi sorry to read abou woes, looks like head removal best bet. once off all hopefully revealed i use steve at vulcan engineering in hanwell i have used there services since the 70s cant recomend them enough. Best of luck colin

[tdafforn]

I second the idea of a big magnet!
Get one of those Neodynium magnets from the back of an old loud speaker..
I use one, and it was strong enough to pick up the whole head!
Only issue was getting it back off the follower...
Cheers
Tim

[alan71]

I once pulled a stuck tappet out by super gluing a spare one on top (upside down) to give you something to get hold of. You will need to make sure all the oil is cleaned off, but with two flat surfaces like that you can get a strong bond with super glue.

Alan.

[GrUmPyBoDgEr]

I once pulled a stuck tappet out by super gluing a spare one on top (upside down) to give you something to get hold of. You will need to make sure all the oil is cleaned off, but with two flat surfaces like that you can get a strong bond with super glue.

Alan.

Now that's clever thinking
John

[john.p.clegg]

You could as a final resort weld something to it so that you can get a grip on it....

John

[johnsimister]

Thank you all for your suggestions and lateral thinking - and no, Richard, this didn't happen in the North Pennines, thank goodness. It has just started to snow here in Arctic Hertfordshire, though.

Further investigation makes me think the outer valve spring has broken, with the broken part jamming the tappet as it moves up. It's much easier to press this tappet down than the others, so there's clearly less spring pressure. If I'm right, my guess is that the 15-year period of inactivity meant that number four inlet valve stayed open all that time, which can't have done the spring any good. So it has now fractured.

I'm about to start taking the head off. Then I shall push hard on the troublesome tappet, wedge the valve open with a piece of wood between valve head and seat, then pull the no-longer-binding tappet out with a valve suction tool. Then out with all the valves, give everything a decoke as required, replace all the springs, put it all back together and drive off into the sunset. That's the rose-tinted version. We'll see soon if it matches reality.

John

[elansprint]

John i have removed tappets in the past by welding a bolt to the tappet to get a grip on it even if you get the valve out be careful pressing down the valve guide the material is hard & brittle & it may crack or push a piece out.
Ian

[512BB]

John
Yes, sorry to hear of your woes. Re head and engine work, i was out for a drive last "SUMMER"? and quite by chance, came across an engineering firm down a country lane. It was a Saturday, and they were closed, but i stopped to have a look through the windows. A chap came out, mainly to admire my car, and we started chatting.
It turns out, that his company used to do all the engine work for Peter Day, one of the best old Lotus restorers to ever walk the earth. You may not have heard of him, as you have only recently purchased your elan, but others will confirm, i am sure. They only stopped carrying out his work when PD called it a day, prob some 6 years ago, no pun intended. Having spoken to the guy, and looking round the premises, i shall be taking all my work to him. After all, if they were good enough for PD, they are good enough for me. They are Cambridge Rebores, i will look out their details if you cant find them on the web.
Should you require a second pair of hands with your car, you know im only up the road to you.
All the best
Leslie