No oil pressure

[rust bucket]

Just got back from Norway and whilst away I lost oil pressure 3 times. It always occured after stopping and starting again when hot. The oil level was full and the warning light was was flashing, its not the sensor as you could hear the crank knocking due to no oil.The only way to get oil pressure was reving it to 5000rpm not good but nothing to loose, and it would build pressure in about 3 seconds then once running it was fine?
I have removed the pressure relief valve and its not sticking and has no scoring and the bike is fine at the moment but for how long. Also my center stand bolt sheared off and when cleaning the bike yesterday the gearbox mounting bolt fell out-bloody hell.
I have absolutely no idea what is causing it, when I started it after replacing the relief valve the oil light stayed on for about a second then extinguished no problem. I have heard that some oil filters can cause this problem, do they have a non return valve. Any Ideas Cheers

 

[rust bucket]

I've checked the internet and have never found a problem like this. It has happened 4 times in total, once in Spain last year and each time it happens it seems to get slightly worse?.The first time I was using 5/50w oil and the second 5/40w both fully synthetic. I don't think its the bearings or oil pump as it seems fine when its running. I'm probably not doing the bearings any good revving it with no oil pressure but it was that or have the bike recovered to a dealer in Norway (too expensive). I figured if it is a major oil problem the at the worst I'm probably going to have to strip the engine and replace the crank bearings.
Its only got 32000 miles on it and I bought it with 23000 and a full BMW service history not that that means anything. I'm at a total loss to what causing it as it happened on the first week then its been fine for 2500miles, its not a oil burner as it only used .25 litres of oil.
I think the oil is draining from the engine into the sump and the oil pump does not seem to able to prime itself but I'm just clutching at straws.

 

[davegs]

I've checked the internet and have never found a problem like this. It has happened 4 times in total, once in Spain last year and each time it happens it seems to get slightly worse?.The first time I was using 5/50w oil and the second 5/40w both fully synthetic. I don't think its the bearings or oil pump as it seems fine when its running. I'm probably not doing the bearings any good revving it with no oil pressure but it was that or have the bike recovered to a dealer in Norway (too expensive). I figured if it is a major oil problem the at the worst I'm probably going to have to strip the engine and replace the crank bearings.
Its only got 32000 miles on it and I bought it with 23000 and a full BMW service history not that that means anything. I'm at a total loss to what causing it as it happened on the first week then its been fine for 2500miles, its not a oil burner as it only used .25 litres of oil.
I think the oil is draining from the engine into the sump and the oil pump does not seem to able to prime itself but I'm just clutching at straws.

Might be a good idea to try a new oil pressure switch first.

 

[rust bucket]

Thanks Dave, I don't think its the sensor because you can hear the crank rumbling and knocking due to no oil pressure and as soon as the oil light extinguishes the knocking stops,you wouldn't believe the noise it sounds horrific. I have ordered a new filter from Motorworks.
I had thought it could be the oil pressure relief valve but that seems fine its not binding and there are no marks on it to suggest otherwise.

 

[cookie]

if it's making the noise as described then the crank bearings and possibly the crank will be toast making the oil pressure worse each time.

 

[Deleted account 211025001]

The noise could be the cam chain knocking. The tensioner is hydraulic.

I've had it knock like a good 'un when the engine has been very hot (heavy traffic, abroad in summer) and running thinner 'synth' oils like you currently have in the bike. Since reverting back to thicker oil it's not happened again.

Andres

 

[birdseye]

5 guage oil is pretty thin . I would be inclined to try a 20/50 oil - the boxer engine has pretty wide tolerances being air cooled and in any case we are not talking a highly tuned multi cylinder racing engine that might justify 5/50 synthetic.

 

[tanneman]

10W50 or 20W50. BMW recommends the 10W50 but since I don't ride the bike in sub zero temps I like to use Castrol Act>Evo 4T 20W50. A bit cheaper and no problems with it.

 

[Sgt Bilco]

I've used 5w oil with no issues last year so wouldn't have thought that was the culprit.

 

[rust bucket]

Thanks for the replies,I only used the oil as halfolds had an offer on and BMW spec 40w oils up to 20c and I knew Norway wouldn't be that warm. When the bike is hot it idles fine with no knocks or rattles at least it sounds ok. It always starts fine from cold and the oil light extingiushes almost straight away but it sounds a bit rough initially but quietens as it warms up. I might try to see if I can plumb an oil pressure gauge somewhere. I'm going to change the oil filter use thicker oil and check the old filter to see if it has a check valve. Other than that I'm just going to keep running it. If the bearings are damaged eventually the oil light will come on at low speed and I'll know its either the pump gone or the bearings are worn although I can't see how unless a previous owner has run it dry? I'm going to cut the old filter open and If I find anything I'll let you know. I would post some photos if I knew how but i'm hopeless with computers

 

[Bendy toy]

This lab test will show if there are metal wear products in the oil. http://www.amsoil.com/shop/by-produ...t-postage-pre-paid/?page=/storefront/oai.aspx

 

[rust bucket]

I think Ottomunch could be right I never considered the hydraulic cam chain tensioner, I've also found that the chain at the front of the engine which drives the oil pump also has a hydraulic tensioner which can also rattle,so this could be the source of the noise.
I've still got find out what causing the pressure loss I'll let you know if I find anything when I get round to removing the filter.

 

[davegs]

Oil light

I had the pro like this on my 1150 the light kept staying on. But when I pulled the wire from the switch it stayed on!. So turned out to be a short in the wire where it passed under the r/h cylinder, repirs carried out all ok. S this could be similar but intermitant.

 

[B4ndit]

I had the pro like this on my 1150 the light kept staying on. But when I pulled the wire from the switch it stayed on!. So turned out to be a short in the wire where it passed under the r/h cylinder, repirs carried out all ok. S this could be similar but intermitant.

I had similar on my 1150. Old bike with bad earthing at dash. Wasn't thinking it was relevant for you but now its been mentioned check your wiring.

 

[Bendy toy]

My oil pressure light kept coming on after a few minutes riding while engine still cold, but there were no nasty rattles. I bought a new switch but the original is working again so it's sitting quietly on the shelf.

 

[Pukmeister]

Just got back from Norway and whilst away I lost oil pressure 3 times. It always occured after stopping and starting again when hot.

My first 2004 model 1200 ran on 10W40 oil as supplied by BMW. Whilst riding through Alton town centre on a hot summers day in heavy traffic I got the oil warning light on at tickover and the start of bottom end knock unless revved. Once out of town and some airflow across the oil cooler and it didn't happen again, although I rode straight to Bahnstormer (then called SPC) and they said don't worry, they all do it when hot.

Within a few months, BMW had revised the oil spec to 20W50 allegedly due to the problem I (and others) experienced.

I would say that 5W oil is going a bit too thin for hot conditions and maybe you should try using a heavier base grade oil and see if the problem is cured. Most 5W oils seem to be used in modern turbo diesels with low ash/SAPS(particulate).

 

[rust bucket]

Thanks for everyones help I don't think the thinner oil helps the problem, however the problem is intermittant and I had 5 bars showing on the temp gauge after a long slow climb with loads of hairpins and it was ticking over fine with no oil light or rumbles.
I'm starting to think it could be the oil filter I'm sure it was genuine, I got it from Motorworks. If the oil filter has a non return valve and its faulty you stop the bike when its hot the oil drains back into the sump, then you restart the hot bike and the pump is struggling to prime itself worsened by the fact I'm using such thin oil.
Will be having a look later in the week when I've got some time

 

[trainman]

Thanks for everyones help I don't think the thinner oil helps the problem, however the problem is intermittant and I had 5 bars showing on the temp gauge after a long slow climb with loads of hairpins and it was ticking over fine with no oil light or rumbles.
I'm starting to think it could be the oil filter I'm sure it was genuine, I got it from Motorworks. If the oil filter has a non return valve and its faulty you stop the bike when its hot the oil drains back into the sump, then you restart the hot bike and the pump is struggling to prime itself worsened by the fact I'm using such thin oil.
Will be having a look later in the week when I've got some time

i don't think the filter has a drain valve, and even so as it sits on its back it surely stays full of oil when engine is off as its pretty close to the lowest point on the engine?
there is an oil thermostat near one of the oil cooler hoses on the top of the engine somewhere, my manual has gone walkies but if you have Haynes or similar I am sure its in there somewhere, I would think if its causing problems then you would notice the oil cooler being cold or colder than engine as it blocks oil flow when the engine is cool, lack of oil through cooler would give your problems in hot riding or running engine with bike static for too long I would imagine
suggest you try what you have said but keep the 'stat in mind

 

[Pukmeister]

Genuine Oil Filter

I just took a look inside a brand new genuine BMW filter I have in my garage spares (part number 11 42 7 673 541). The filter body itself is marked 1142 7673541-01 517504-10 12W37 Made in Austria.

It does have an internal relief valve in the centre of the element housing.

Can't see how it would make a difference to your oil pressure unless your current filter is blocked/contaminated and the relief valve has failed to open and bypass the element. I presume your bike was otherwise serviced as standard prior to using the 5W grade oil ??

Only one incidence of oil filter causing engine damage I can recall from years ago on a badly neglected VW Golf 1.3 Petrol I took a look at (cheap pattern filter, no relief valve, oil like treacle).

A very good point above about a possibly jammed oil thermostat.

.......As the great Toyah Wilcox once sang "It'th a Mythtery"

 

[rust bucket]

Ok got my parts from Motorworks today, the filter is not in BMW packaging but is made by Mahle Part no 0C306 whom I assume supply BMW. There seems to be some sort of valve located in the center and when I remove the old filter from the bike I intend to cut it in half and have a look. There is a an oil thermostat in the oil line however this does not affect the lubrication circuit as the engine has two oil pumps - one does lubrication, the other cools the exhaust valves and although the pump is one unit the two circuits are completely seperate.