Morris Minor Owners Club

My 1098 minor smokes badly at tickover. I have removed the head and decoked, replaced valves and valve guides. fitted top hat seals on the inlets and new std seals on exhausts. New head gasket. Put it back together and set the clearances.

I have static timed the engine to 3 degrees before tdc (although this is a bit of a guess because the pointers are hard to read!) I have set the mixture to the best of my ability. i lift the pin and it just increases a little (although the plugs look rich to me).

I have compression tested the engine and all bores sustain 180 which seems pretty good to me.

If I drive the car the smoke clears and runs well, until I stop and then after a while on tickover the smoke comes back and the longer it ticks over the worse it gets. Even if revved up the smoke is still there, only clears after driving! I can drive it hard and get no smoke! The smoke is grey and I would have said looks like oil smoke but I just cant see why its happening.

Any Ideas anyone?

Strange since you seem to have done everything! you could get whiteish
smoke caused by water but you would see a drop in water level and, if
it is oil you should see a drop in oil level. Timing will have no effect on your problem.

I haven't really driven it far enough to see if the levels drop smoke clears after quater mile or less, but I suppose if i use it for work this week it will give me a clue. could be white smoke but looks more greyish to me! How can I test the breathers could this be a problem?

if your 1098 is the type with an outlet from the rocker box straight into the air filter then just remove the rubber pipe and blow through it as they can get clogged with mayonnaise gunk. then reconnect the pipe to the rocker box end and blow hard through it to clear any obstruction inside the box. if your breather pipe goes straight into the carb' then ensure that you have an oil filler cap which has the wire filter in it.

Well I checked the breathers and they are clear. took the top pipe which goes to the air filter and this is clear, I can blow into the rocker cover too. Theres no cream present at least no this morning when I had the rocker cover off. I took the tapet cover off and blew through that breather pipe too. Seems fine. I have the un-meshed filler cap so i guess thats not the problem. How else can I check for water getting in?

The only way I can think of is to check for water level dropping. It is possible that bubbles could appear in the radiator but probably difficult to see. When you have done considerable work on an engine it sometimes produces smoke as various coatings wear away with use, I have no other ideas.

Your compressions sound excellent - but there could still be a problem with the oil control rings. If you fast idle the engine - and remove the oil filler cap - is there a plume of fume/smoke ? You should also try putting one of the breather tubes to vacuum - later carbs have a connection for this on the side. And - do you have a servo fitted ? These can sometimes leak hydraulic fluid (scarey!!) which results in whitish smoke - but usually as a 'puff' just after braking. If it's none of the above - then I'm afraid you will need to pull the pistons and have a good look at the oil rings.

No plume of smoke with filler cap removed and no servo fitted.

I did wonder about oil control rings but thought it would smoke under load too. However i seem to be left with oil rings or cracked block/head. i'll run it for a few days and check the levels so I know for sure if its oil or water.

Any tips for finding a cracked head or block?

I doubt it will be either- that would involve water consumption and steam. I suppose it's just possible that somehow the oil for the rocker gear is finding it's way across the head/block surface and into the bore of #1. But it seems a bit unlikely.

so its more likely oil rings then.
If i'd stuffed up fitting the head gasket it would show on compression test right?

Yes - but what's the history of the engine? Has it just had new rings fitted ??

no, I just bought the car a few weeks ago. As it was smoking at tick over I thought i'd do the head. Figured oil was coming down not up!

Hmmm - ask the vendor!

do you think its likely that its had new rings recently then? Theres nothing in the service history and the previous owner told me about the work he had done when I bought it. He certainly didnt mention rings and claimed not to have much mechanical knowledge! I knew there would be work to do and I dont mind doing it if I know what to do!

Well it turns out that the number 4 piston is badly scored below the rings and the bore also is scored. I guess as the scoring is low in the bores it wasn't dropping the compression but was allowing oil past as the rings could't seal. There are some metal fragments in the sump and rubber which looks like it may have been a seal but as yet I dont know where it came from!

So its a rebore and rebuild. Oh Joy, but at least the puzzle is solved.

Is the smoke too much to just 'live' with it - at least for a while ? There are sometimes quite low cost 1098 engines on ebay/on here - would at least give you a simple swap-over. And then your own engine could be investigated/overhauled at leisure - and either sold or swapped again!

Is the smoke too much to just 'live' with it - at least for a while ?

The MOT ran out last week and it wouldn't pass another with the smoke!

I would be interested in a replacement engine but I don't want to hang around and I could end up buying another pup! At least if I rebuild i'll know the engine is sound.

If anyone has a good engine or just a std block with good bores for sale around Dorset area let me know!

Run a search on ebay under '1098'