Atlas White Smoke

Have you drained the sump to make sure that it is not oil build-up there which is causing the problem ? ...and it couldn't have been mis-fuelled with diesel could it ? That causes lots of white smoke. I discovered that the hard way !

Socket 1/4 Whitworth. RGM sell a box spanner for that task.

look at this

https://www.youtube.com/watch?v=UcGsy4u58l8

If the bike had wet sumped and you started it without draining the sump then put the bike back together, drain the sump and try again before removing the head..

Could this simply have been wet sumping? If the bike had been standing a good long time it would chuck out white smoke and even smoke rings for a minute or two. Run it for 5 minutes and if it stops smoking it would indeed be wet sumping. In that case the simple solution would be to drain the sump before starting (but make sure there is oil in the tank first) and starting should be a smoke-free procedure.

Personally, I don't bother draining the sump on my Dominator if it has been left for a while. I just make sure the shed door is open to disperse the cloud when I start it.

Maybe too late now but next time do not stick to 40mph, give it some revs under load to get the rings to seat.

Maybe too late now but next time do not stick to 40mph, give it some revs under load to get the rings to seat.

I wonder if the pressure release ball valve in the timing case has stuck? It happened to me years ago. I can't remember exact symptoms but I do remember lots of smoke from oil in the wrong places.

Previously john_holmes wrote:

look at this

https://www.youtube.com/watch?v=UcGsy4u58l8

That is a little unfair, John. The bike in the video is not even a proper Atlas. It is an N15 mounted high up in a featherbed so that the head can't come off.

Head removal-Atlas no issue. remove all bolts/nuts and of course the head steady. Get astride the bike, raise the head with your hands either side (where the plugs would be) than use your fingers between the head and the barrels to raise/jiggle the push rods up inside the head, tip the head back and out.

No problem.

Looking forward to the next installment.

It is possible that oil was put in to protect, if not then you will be back where you started. I would have heated the head up and tapped the valve guides out enough to put some sealer round them,also checked that the rocker spindles were the right type and turned the correct way round. Piston oil ring type is also important with later oil bleed rods. oil drain hole clear in head and all the way down?.pressure release valve stuck?.oil returning to tank?.Oil residue from previous attempt to start with full sump?

Compression rings can be put in upside down and be a problem, New bores need bedding in , oil bleed rods need their own type of piston rings ,head not tightenned down evenly, oil getting accross joint, plenty of things to check,don't be in a rush to reassemble till you have checked around, Easiest thing to take down and rebuild and be back to square 1. Been there ,done that, most frustrating.

Hello Now what year is your Atlas I ask this because there are two types of oil pumps fitted to The Norton Atlas Early machinery had the 3 Start oil pump and after 1965 every thing went on to 6 start oil pumps and higher oil presser so to balancethis out they fittedpain rocker shafts and bleed hole in the con rods and shell bearing, where as the early models had NO oil holes in the shell bearings for the con rods so my prognosis is you have oil consumption and since the rebuild JMC will not know this information and fitted the later type shell bearing so your bottom end is not getting the right oil presser and the oil pump is over oiling the large ends which is the cause of oil getting up the bore and the oil ring not being able to cope with the large amountof oil and your engine runs rough oiling the spark plugs and you have oil coming in from the push rod tunnels to has the cylinder head was not torqued up right you do this in stages starting with the center nut by nipping it up first and then the 4 side bolts the rear one the two under the front the last two up front of the head then go around again, Now I just stripped a Norton Atlas Bottom half it is 1963engine bottomhalf and been rebuilt by some IDIOT who as used blue silicon on the crankcase halves and in doing so he has blocked up the savageside hole in the cases and fitted the wrong shell bearing and to top this off has fitted two odd con rods into the bargain no woulder there were signs of picking up on the shells so the crank needs a regrind now, all becauseof wrong shells and a blocked savage hole I only use STAG wellseal sparingly with a artists bush that all you need a thin layer of WELLSEAL will do the trick, Siliconsealants are NOT to be used ON any Vintage Nortons and make sure all mating surfaces are true before any engine assembly

Yours Anna J

Hi Anna,

Thank you for your information, i have got 03/03/1967 on the log book, and engine crankcase numbers 2C/115983/P if that is of any help.

I was at a bike night in Skegness last thursday night and got talking to a fellow british biker and i got round to talking about the Atlas with the smoke problem and he basically said most problem solving can be performed without taking the engine out and he seems to reckon its the oil pump pressurising up and throwing oil up the bore.

Maybe a sticking ball in the pump and check it is pumping oil back to the tank.

I have sorted the clutch and will post the results on my other thread

Andrew

Hi ,

A update with the progress. I put new castrol 20/50 oil in the tank 2.56 litres, and some fresh fuel in the tank and she started second kick. I checked for oil returning to the tank which it was at a nice pace then it slowed up a little, but no white smoke. I thought this is too good to be true which it was. The engine breather pipe was throwing some out on the floor i thought fair enough and then i looked at the right hand carb and i saw what i thought was fuel dripping down the back of the barrel . It turned out to be clean oil instead of petrol which was a relief . So i have just got to find where the oil is seeping from.

I am not out the woods yet because the oil is going three ways and if it wasnt would i be pressurising up at the bottom end .

Andrew

The cam followers may be reversed? They drain quicker the correct way round.

Before taking the head off again, which can get a bit frustrating, try going round the head fixings with a torque wrench (in the correct pattern of course) , take care as its easy to overdo this if the data is wrong. It stopped a similar leak on my 99. Avoid stainless bolts.

White smoke is oil, could be going past valve seals or round the outside of the guides . A good way to find out whether the oil is comming from the head or from the pistons is to block off the head feed and ride it. Sounds a bit drastic but it won't do any harm for 5 miles at least. Smoke stops ,its the head,smoke carries on its from down below. You are then not so clueless!!.