Keith
173 posts
Joined: 13/09/2004 07:56:05
Location: United Kingdom (Excluding channel Islands)
A-Hem...
On A+ motors for many years valve stem seals were fitted to both inlet AND exhaust valves to help with emissions issues. The seals do not melt on the exhausts. If the oil smoke/blue smoke does not appear at aby other time than start-up, it isnt a huge issue YET. But suggets theres oil leaking past the guides. If theres blue smoke out the exhaust on acceleration - this usually means the piston rings/bores are work out. If theres blue smoke on decceleration, then its likely to be the guides. The problem here is - assessing what the problem is unless you are pretty knowledgeable. Fixing the problem can rapidly escalate in cost. Generally its cheaper to simply go for a reconditioned head - that way all bases are covered if youre not sure what you are looking at. KC.
Posted: Feb 06, 2006 11:16 PM
T. Perks
57 posts
Joined: 19/11/2006 09:21:16
Location: Wotton under Edge United Kingdom (Excluding channel Islands)
non cooper 1275 90's intake valve size?
if youre only doing 7k then i wouldnt bother using hard seats, in my rally car i dont use them and im sure it gets a harder thrasing than any road car, i also dont use any additives just the best shell optimax type stuff, as for guides use std iron guides for std valves and use alloy bronze for stainless valves, again on my mini i use bronze on the inlet and iron for the exhaust and no stem seal.
Posted: Feb 12, 2007 01:59 PM
John
1948 posts
Joined: 28/05/2006 16:49:46
Location: cambridge United Kingdom (Excluding channel Islands)
White smoke From exhaust
the valve guides and seals are just most likly a little worn, when u start the oil that has run down these from being stationary gets burnt off. its nuthing to worry about common thing with higher milage/older engines.
Posted: Jun 13, 2007 11:30 PM
MS
7 posts
Joined: 18/04/2007 04:49:18
Location: Kota Kinabalu, Sabah Malaysia
Attached please find the photo shows on the white smoke exhaust out from my mini. Besides, i notify some water came out from the exhaust pipe as well.
If the valve guide & seal is worn, is it difficult to repair the worned valve guide & seal?? how much need to spend??
Posted: Jun 15, 2007 10:30 AM
cylinder head
id get head rebuilt, a 1983 head wont have hardened seats so valves may well be sinking causing poor compression as they are leaking. valve guides are prob worn seals are prob well gone by now. cheak compression with bit of oil in cylinders if it still doesnt improve ur valves are prob the truble, if it does improve its the piston rings/bore wear.
Posted: Sep 14, 2007 03:37 PM
Roobz
223 posts
Joined: 15/12/2005 01:31:36
Location: Redbridge United Kingdom (Excluding channel Islands)
oil burn on over run
Sounds like worn valve stem oil seals to me. if there worn or not even there, then oil will be sucked down past the valve in its guide and then burnt.
Posted: Sep 26, 2007 05:27 PM
if it is the valve seals/guides it will normally smoke on starting. it is common thing on older engines the oil runs down seals when left then burns off in first few seconds of running. it isnt normally seen in normal running just on starting. if its smoking during running it will either be to do with piston rings/bores or crankcase ventilation.
Posted: Sep 28, 2007 05:50 PM
Tim
1850 posts
Joined: 18/10/2004 09:40:59
Location: Bournemouth United Kingdom (Excluding channel Islands)
smoke
It could be valve stem seals (most likely) or it could be badly worn cylinder bores. Did you replace the seals when you did the head gasket? Even with new seals, you can get oil problems if there's a lot of wear in the valve guides (i.e. side to side movement of the valve). Have you done a compression check on the cylinders?
Posted: Jul 07, 2010 10:40 AM
diddi
37 posts
Joined: 13/09/2004 09:03:12
Location: St. Ingbert Germany
Smoker
Might be worn exhaust valve guides/stem seals. Cheers, Diddi.
Posted: Jan 17, 2005 10:10 PM
Blue Smoke - Valve Seals
I dont think its possible to change the seals without removing the head. You then release the valve springs and bobs your uncle. While the heads off, it will be worthwhile checking the valve guides, and replacing those if necessary. Its probably worth doing a compression test first, as that will give you an indication of bore wear. No point overhauling the top end if the bottom ends gone as well!
Posted: Jan 31, 2006 08:19 PM
An interesting variation
seals and or guides are worn keith calver does some uprated ones that will hopefully last little longer than the rubber ones. ul need to replace headgasget and have valve spring compressor to replace them urself. personally id not worry too much about it just top up and change oil regarly. 6000miles as a min between changes, the more frequent the changes the longer its gunna last. use 20w50 oil as it needs thick oil for syncro in gearbox.
Posted: Sep 13, 2007 10:56 PM
J. Clarke
Colourtune
u fit new valve seals too on exhaust guides? if your mini is pulling to one side its likly that one of the front brake caliper pistons is seazed. if its pulling right will be left side one doing it. rear may also have issues but dont normaly cause such major problem as rear contributes small proportion of stopping force. rusty discs may also not be helping if one side is worse than other for some reason. so i suggest a pair or rebuilt calipers, new hoses, disc and pad kit (minispares do one for just £23 with ebc blackstuff pad). its worth getting it properly sortted as it is dangerious if you have to brake hard on dual carrageway can pull u into anouther car or lorry, thas how my m8's sis mini ended its life and iv almost been in same situation with my beamer.
Posted: May 23, 2008 11:54 PM
That looks like oil smoke to me! Water droplets are quite normal while the engine warms up.
The seals are little rubber caps that fit over the inlet valves. They cost virtually nothing but you have to take the cylinder head off to get at them, and this in turn means replacing the head gasket when you put it back again. But it's a simple job for most mechanics.
The valve guides are more work. Again the cylinder head has to come off (so it makes sense to do them anyway if you've got the head off to change the seals) and you have to press or hammer the old guides out, and carefully press the new ones in. This is best done by freezing the guides in your freezer overnight, and warming the cylinder head carefully over a gas burner, as they are a very tight fit.
You may also need to replace the valves themselves if they're worn. The cost of the valves and guides isn't huge, but it's several hours' work so if you're paying a mechanic rather than doing it yourself that's where the main cost will be.
Hope this helps.
Posted: Jun 15, 2007 03:13 PM
Thanks for your reply massage. Mr. Tim Robert & J. Clarke.
I will plan to replace the valve guide & seal nxt month and replace the head gasket as well.
Posted: Jun 16, 2007 02:06 AM
little_mini
23 posts
Joined: 14/05/2006 07:23:43
MPI CO too high at idle?
You might have a slight oil leak or loose valve guides. I had a CO measurement off the scale once when the inlet valve seals failed and let a little oil in.
You do have the CAT fitted still with that RC40 exhast don't you?
Posted: Jun 29, 2006 07:44 AM
sheers
2 posts
Joined: 13/11/2005 10:54:21
Location: hereford United Kingdom (Excluding channel Islands)
smokey engine
just had head converted to run on unleaded on my 67 998 cooper new valve seats valve guides and stem seals put back together but now the engine smokes very bad, it used to smoke a bit before but i thourght by having the head done it would cure it, also i run the car up the road for about 10 mins and took the rocker cap off and there seems to be a build up mayonnaise in the rocker cover in that short time,all the breather have been cleaned .any thoughts???
Posted: Mar 06, 2006 08:31 PM
burning oil
That's a fair bit of oil to be getting through, and if it's not dropping on the road it's surely coming out of the exhaust as a light blue haze which you might not be able to see in your rear view mirror but I bet the guy behind you can see it and smell it!
New rings may help, but it depends how badly worn the piston bores are. Only opening it up will tell. Also worn valve guides and seals will contribute to this.
Posted: Jul 04, 2006 10:03 AM
James
161 posts
Joined: 28/06/2006 11:39:53
Location: Downham Market United Kingdom (Excluding channel Islands)
Ohhh dear!
Hi Chris, Nope, running the complete 1098 setup, with fuel additive... keeping the 998 head, as that is going to be part of the eventual 998 rebuild project, so we will eventually have a complete 998 again! Pistons are dished on the 1098. Gotta consider a head stripdown and rebuild though, as Ive just moved it off the drive to let Clair out in my Pug, and it was a tad smokey when cold... its alright when hot. Reckon it could well be the valve stem seals, being the silly little O rings, and some oil has run down the inlet guides when warm and thin with the engine stationary. Had a MK1 Astra that was a pig for that, until I did the head! Shes still a little rocket though! :-) James
Posted: Aug 08, 2006 08:19 AM
998 Unleaded Head For Sale
Appears to be an aftermarket head, as no U can be seen in the casting number.... Was removed from a 1989 998cc City. Its obvious that new seats have been fitted at some stage, just by looking. Seats in A1 condition. Could really do with new valve guides, but never smoked, as proper stem seals fitted as opposed to O rings. Just the bare head on offer. Make me an offer! Cheers, James g0fhm@cqmail.net
Posted: Aug 09, 2006 04:06 PM
jag_clarke
engine
oil pressure may be set too high its determined by spring in oil pressure release valve could also be sticking. if the smoke is at start up usually indicates that valve guides/valve guide seals are worn if its on acceleration then worn bores/piston rings may be issue. That model didnt exist in uk, there were several factorys in affrica making bmc cars this may of been from one of them they didnt follow the uk specs/models. however think they mostly ended in 70's so may be export.
can u please clarrify that u mean when u say when your car is at high compression?
Posted: Nov 04, 2008 01:12 PM