BXProject

mnde · Post by **mnde** » 10 Dec 2007

Right, since BXC is well and truly fooked I'll post my tech query on here.

Twice recently I've left my BX standing for two weeks and after (eventually) getting it started it's somewhat noisier (tappy/rattly) than usual for the first few minutes, after which it settles down to normal.

Is this because it's overdue for an oil change, or my oil isn't thick enough to be pumped to where its needed quickly enough? Or what? I've been using Total 15W 40. The oil level is halfway between MIN and MAX on the dipstick. I've laid up the GSA for long periods but as far as I can remember it's never sounded any different from normal when started.

Cheers,

Mark.

mickey taker · Post by **mickey taker** » 10 Dec 2007

could be valve stem oil seals are on there way out and the oil is draining down the valve stems ,

does it smoke a bit on start up ? coz that would probably confirm it ,

I would deffo change the oil and filter as well though

Philhod · Post by **Philhod** » 10 Dec 2007

How many miles on the Meteor ( I presume that`s the one we`re discussing here) As the engine gets on a bit the spring and drive to the pump(oil) weaken. couple this with the fact that in the length of time standing, all the oil will have descended into the sump. It`s quite a way from the sump to the camshaft, hence the noise, which dissappears as soon as the slippy stuff arrives.
Another item which will exacerbate the noise is the tappet settings. when was the last time these were checked and re shimmed accordingly? Hint, it`s a head off job to do it properly

the good bit is you do the stem seals at the same time, also clean up and regrind in the valves

Hey! top end good as new

mnde · Post by **mnde** » 11 Dec 2007

The Meteor's done roughly 100K and I dunno when the last time the valve clearances were checked. Probably about 10 years ago when according to the service history the cambelt went byebye and all the valves, seals, gaskets etc were replaced for a rather large bill. I would rather like to check em because it's always been a bit rattly on the move - not at idle.

The BOL does recommend 15W 40 *or* 20W 50 so maybe I should try the higher grade to help out the pump? (I use it in the aircooled GSA as oil pressure is crucial) Or perhaps invest in some good old Castrol Magnatec? Or something similar supposed to leave a film that protects "from the first turn of the key".

Was unaware it was a head-off job...

Thought it was just rocker cover, check clearances, then if needed cambelt off and remove camshaft and tappets/shims? Still a bloody faff compared to a TU engine...

I don't think it smokes on startup, but I'll ask someone to stand behind one day and find out. It's got that black ring round the end of the tailpipe though.

Cheers,

Mark.

Post by **Vanny** » 11 Dec 2007

Philhod wrote: Hint, it`s a head off job to do it properly

Why is it a head off job? Does it not have buckets ala the XUD? Will it be a TU engine then? or a K series?

I ask as i can see it being a job i'll need to do one day, only done clearances on the XUD (and found TWO very friendly engine repairers who where happy to supply shims to any size, which was nice)

Philhod · Post by **Philhod** » 11 Dec 2007

It`s just a question of the last word PROPERLY.
Like, if the shims do need doing all the other stuff will need doing also. If you are going to remove cambelt and shaft anyway, it`s hardly any more work to do, to sort your top end for another 100k is it?

David · Post by **David** » 11 Dec 2007

I think the point is that to "do the valve clearances" is indeed just a cam out job, but the very fact that the valve clearances need adjusting in the first place points to something more serious. XU/XUD engines should never need the valve clearances adjusting between major overhauls.

Mark... When you start the engine from 2 weeks of not using it, does the oil pressure lamp take noticeably longer to go out? If not, then I don't think that is the problem, as the moment there is oil pressure there will be oil in the head too.

Other than that I struggling to think of anything else that would be different between startup after 14h or startup after 14 days. The petrol in the carburettor may evaporate, but that will be replenished within seconds. Err... maybe something like deposits on the valves that are left open moving a bit over 14 days and jamming in the valve seats for a couple of minutes until they're mashed away...

Dunno...

docchevron132 · Post by **docchevron132** » 11 Dec 2007

Indeed, valve clearances, easy, cam out. Jobbed.

But as Phil mooted and David said, if you've reached the point where the tappets need adjusting, chances are the valve seats at least will need recutting, or replacing..

XU's are known for being a bit rattly on start up when left for periods.
Especially the XU5 and XU9.
If theres no clouds of smoke on startup, and the rattle goes quickley after start up, I really wouldn't worry.
If it gets worse, or doesn't go away that would point towards low oil pressure.
the heads in these can suffer from oil starvation problems.
Weak relief spring in the pump would do similar things, although thats usually accompanied by the bottom end knocking.......

David · Post by **David** » 11 Dec 2007

That's a good point actually... The XU9 in the digit rattles rather on startup if its not been run for a while. Doesn't actually sound particularly sinister, just rattly. Goes away fairly quickly though.

smiffy · Post by **smiffy** » 11 Dec 2007

You should have heard the rattle I got last time I changed the cylinder head on my C15D!!!

It was a very dry, (read no oil in there at all) head, which had been gathering dust for ages. I was told the shims were ok, and the cam was present, so, jus fit it, and drive home.

I did just that, and it took 15 miles for the thing to shut up, and get some oil into the shim buckets!

Rattly engine after layup