Sounds nasty now - why?? Test your ears..

I couldn’t resist grinding the valves while it’s off. Nothing to lose and it’s the best way to get a look at the condition of them.

Got all the rollers and slides out and they all look good. Got 4 of the tappet guides out but 4 won’t come out. Is there a knack to get difficult ones out? Manual says something about a service tool which I don’t have. The others slide out easily with just a long finger. These 4 won’t budge…

Mine come out ok, you will have removed all the little bolts. you need something to pull them out from bottom …. Threaded bar with rectangular bar on bottom to suit slot turn 90deg or bolt and strong cable and lever them up.
What’s cam lobes look like , rollers and slides nice and free in slots ? could try tapping them down a bit first to loosen them but if they won’t come out need to make sure they still align with bolt holes

Got another one out but last 3 will spin freely and move up and down a bit but get stuck near the top. Might make up a puller or am tempted to leave them in as they, and all the others, look in good nick.
All rollers and sliders also look in good condition - nothing missing or split and still seem shiny and move freely. See pic:

Cam lobes also all look good - clean and shiny and when turning with my finger on them i can feel no flat spots or issues. Hard to get pic that's worth a damn but here's an effort of a couple of them:

In short - seems to me like what we thought might have been the issue doesn't appear to have been. Unless I'm missing something (easily possible...) then all the components look to be good and should be doing their job fine. Will give everything a good clean up anyway ready to replace at some stage.

While I was there I took a closer look at the pistons - all move smoothly and bores look clean and no scores or scrapes. Piston 1 though does have some pitting amongst the carbon - see pic - but don't think that's any cause for concern is it??

Got a spring compressor coming today or tomorrow so plan to remove the valves next since i'm checking everything else. But am beginning to think I'm not going to find anything that could have caused the noise in the top end and maybe i'll need to go back underneath and look at the shells after all.
If any of you think i've missed something do shout!
On the plus side with no pressure to get it running on a deadline, and this all being new to me, and it not raining, it's actually been an enjoyable strip down so far with almost all going to plan. Which is rare and i've probably jinxed it now...

The top of that piston has been hit bi sumthin. I’d guess a loose swirl pot.

it’s in the wrong side so something has been floating about in there. Won’t be a valve but something hard enough to make those repeated impressions.
May have been years ago.

Progress update: Got everything off and cleaned up now, including valve springs & stems etc. Most components looked in good order - though a couple of the stem oil seals weren't attached and were free to bob up and down. Will put on a new set when I re-assemble.
That No 1 Piston has definitely been bashed about by something - though don't know how long ago, or for how long - cleaned up you can see fairly nasty damage:

God knows what got in there but it ain't there now (it's possible it was in there but when i removed the head it fell out - certainly i didn't see anything).
Bores all look good and rest of piston heads fine.
Did notice some slight play in that No 1 piston though - in that at tdc i could move it ever so slightly in the bore - maybe 1mm or so. none of the others had any noticeable play. Compression test when engine last running didn't show any issues though.
Bearing in mind a re-bore or anything major like that is pretty much out of the question financially do you think that amount of play is a disaster at this time? Inclination is to leave it but could that be the cause of the noise do you guys think?

Movement up and down or side to side?

Entirely up to you obviously and only you know where to draw the line but I’d be tempted to renew that piston.
All my pistons rattled 1mm left to right when I stripped my engine. Very little back to front, but the oil filler neck blew like a compressor when running.
If the compression test was ok then might be worth not going down that particular rabbit hole. Unless of course that was what the noise was.
If all the divots were covered in old carbon then possibly an old issue.

I’d be having a look at the bottom end before the head goes back on. You don’t want to be taking that off twice.

How do the rockers look. Check the surface that meets the valve top for hollows.
If they have a dimple in them it’s almost impossible to set their gap with feeler gauges later.
I had to polish mine flat (following the curve) with a diamond stone but fitted a set of caps on the valve stems when rebuilt off the later engine. They increase the surface area and help it not happening again. Not dear.
If all else fails you can set dimpled ones with a dial gauge rather than feeler gauges.

WoodyO said:

Movement up and down or side to side?

Click to expand...

Side to side ever so slightly

In for a penny, with the big end caps caps removed you can push the pistons out through top , this allows to check for big end shells, broken piston rings, check piston sides and gudgeon pin play , you will need a spring compressor to get them back in but they’re cheap.
If those all ok then you can check main bearing caps removing one at a time , check and replace.
You expect the top half of conrod bearings to be the most worn and bottom half of main bearings, if worn you will start to see the copper showing underneath the white metal

No need to buy a ring compressor. I got one a month or two back to do mine and I hope to be dead before those pistons come out again.
If the pistons are coming out PM me your address and I’ll get it over to you.

What does intrigue me is those pistons ain’t got the ‘V’ in em.
Wonder if they are off a petrol.

You’ve got to feel sorry for those that buy a new car or know it’s history. Look at all the fun they miss out on

Bobsticle said:

No need to buy a ring compressor. I got one a month or two back to do mine and I hope to be dead before those pistons come out again.
If the pistons are coming out PM me your address and I’ll get it over to you.

Click to expand...

Top man - Thanks. If it comes to that I’ll shout. (Mine is a petrol btw - but you’re still right, trying to work out what’s happened to it in its previous ownership is always a joy!)
Thanks again for the offer - and all the help from everyone so far. Not off again til Friday now so things on hold (time to ponder pulling the sump again and doing the bottom end - sensible - or double check rockers and reassemble and see (lazy)

TS2304 said:

Top man - Thanks. If it comes to that I’ll shout. (Mine is a petrol btw - but you’re still right, trying to work out what’s happened to it in its previous ownership is always a joy!)
Thanks again for the offer - and all the help from everyone so far. Not off again til Friday now so things on hold (time to ponder pulling the sump again and doing the bottom end - sensible - or double check rockers and reassemble and see (lazy)

Click to expand...

Ah. Petrol. No wonder trying to work out what would make those shapes from a diesel head. Must be a bit of spark plug.
That’s an hour I won’t get back.

Ha.oops sorry. I did mention it first up but it was a lot of pages ago now and age affects the memory ;-)

*Update*
So having had the head off I cleaned up everything (left the piston in the end as figured as the compression was fine, it was probably OK). Replaced the cam followers as on closer inspection a couple had small flat spots. Cam lobes themselves seemed to be OK tho feeling them from the top down. Put on new stem seals. Double checked rockers and all seem OK. Surprised myself by putting everything back together easily and without incident. Re-set tappet gaps to [EDIT - thanks lynall!] 0.25mm - all surfaces smooth and level. Fired it up - started first time. But the noise is still there. No change that I can discern.
Sounds like this (sorry won't embed for some reason):
https://youtube.com/shorts/BjnifiJpacQ
I could swear the noise is from the tappets - sounds to me like middle of engine at the top. But having just stripped it all and put it all back nicely I can't for the life of me figure out where or how the noise could be happening.
Be happy to hear any ideas - could it be 'piston slap?' (I don't really know what that is but read about it and as i had a slightly loose no1 could that be something??)
Failing any new thoughts I guess I have to take the bottom off and look at the big end caps and shells - though still sounds like from the top to me but I'm running out of things to take apart..

Is one of the rockers loose on the shaft?

Col

well they all rock freely ...
when i put them back on the shaft there was nothing to 'attach' them in any way - just held in but the springs and the fixing bolts to the head on the relevant ones. You think they can slip about somehow? Didn't spot it when ran previously with cover off, but can certainly take it off again and look once more next time i get the chance

It would be unusual for a rocker to have to too much play but it must be possible. They obviously should rotate freely but there shouldnt be any free play. If any rocker can be moved up and down in relation the the shaft there is a problem

Col