re oil evaporation

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Hi all been a while since I have posted I have a problem with my modern diesel engines seems I am using a lot of oil I have fitted a provent 200's on all my modern diesel engined vehicles I use the vehicles fortnightly for a 4000 kilometer trip in that time I use about a liter of oil the oil is being caught in the provent catch can each time I do a trip I end up with 500ml oil in the catch tank under the provent The vehicle has a 15,000 service interval this is the 3rd CRD type diesel I have owned and this one had 3,000 k,s on the clock when I bought it I fitted a provent to the other vehicles same problem I was originally using amsoil euro 5W40 but the cost versus usage I decided to go to a mineral oil the usage of oil diminished dramatically the grade of mineral was 15W40 I started to use the same 15W40 mineral in my older higher mileage vehicle as it was evaporating of the synthetic oil as well in that vehicle I plumbed the provent with a check valve back to the motor sump so as not to have to check the engine for oil usage as much Back the the 2013 model I switched from 5W30 factory fill to amsoil synthetic 15W40 diesel oil the catch tank is full again Last service I went back to a 5W40 penrite low saps oil no difference the catch tank is full again after a trip when I look at the oil that is coming from the the provent its horrible and I can only imagine what this must have been doing to the engine going back through the crankcase breather mixing with EGR gas then into the combustion chamber I have also had the EGR valve switched off on all my diesel engined vehicles through a tune of the ECU I do this to all my diesels having had to rebuild my first modern diesel engine because of this problem Since switching of the EGR's and fitting the provent's the engines blow hardly any smoke only the tell tale puff under hard acceleration The engines are still consuming oil not through the engine through the crankcase breather into the catch-tank under the provent What I am trying to figure out is it the oil I am using or is it my driving style I usually sit on the speed limit using the cruise control drive fairly conservative to get the best fuel economy which is fantastic just seems I have a lot of oil coming through the crankcase breather At my next service I am going to use a low saps 229.51 rated 10W50 to see if this controls the oil usage I did not want to attach the return of the provent back to the sump on the new van or the jeep as I intend intend keeping these vehicles for a long time and looking at the oil that comes from the crankcase breather it horrible the thought of plumbing it back t the engine is not appealing Any ideas on this would be appreciated
 
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I don't think that the oil is evaporating...it really can't get that hot, except in the turbo, and the ring belt. Bulk oil temperatures, the oil floating around the cylinder head etc can't be any more than 150C top end IMO. Given that you have a couple of them doing it from my reading of your post, I'm wondering if you have removed the restrictors that were (probably) in your pipework from the factory...I know that there's one in my Nissan, and it's comparatively tiny. Particularly big 4 cylinder diesels will have quite big pressure pulsations in the crankcase, as there's a big difference in crankcase volume between 2 up/2 down, and 2 halfway either direction...6s are better, 8s better still. The restrictors try to stop the crankcase "breathing" in and out twice per revolution. My guess is that the crankcase breathing has some pretty high velocities that are carrying excessive amounts of oil to your set-up. Find the OEM restrictor, and try it in the supply line to your provent.
 
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Are there any baffles inside the engine, just before the PCV? They should help reduce liquid down the pipe. Too much blowby? Give Redline oils a whirl, they're great!
 

XJR_Boy

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Thanks guy's When I fitted the provent's I didn't remove any restrictions just plumbed them in line where the crankcase line went from cover to inlet manifold on the Jeep I even used the original hose because it had some sort of design we thought was a restrictor of some sort I have just fitted another provent to my mates Audi A3 diesel because he was complaining about the oil coming from the turbo when we fitted the provent we cleaned the intercooler and pipes and cleaned the whole inlet system got nearly a litre of oil out of it same thing when I fits fitted the provent to the Jeep the intercooler had a litre of oil in it had to get it ultrasonically cleaned to get all the oil out of them It is pretty hot where I live its 8.35 in the evening middle of winter raining and it,s 21 degrees celcious still My oil supplier recommended 20W50 and I might try it for the van when it comes to summer just that where I go its cold well sort of -3 the other morning when I got up to head home but thats 2000 kilometers from home I just bought a 20 litre drum of 10W50 with Mercedes rating 229.51 that's mercs highest rating its also low saps I don't worry about low saps got all my EGRs switched of and run provent's to stop the inlets gunking up When its due for next service I'll try that just want to have one oil for all my diesels hate having to use so many different oils got 5 cars and 5 different oils not to mention my bikes I don't know what NOACK is so please enlighten me
 
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NOACK is a test at which oil is heated to a 150*C and total oil evaporation loss is measured. To meet basic A3/B4 spec limit is set at max of 13%. C3 is the same IIRC. MB( and some other manufacturers) limit this lost to a 10% max on some of their oils.(229.5/229.51). They oils are generally used in a engines that are on variable oil change interval. I'm not sure your problem is oil related. Plenty of small diesels in Europe, non of them use anything thicker than 5w40, even in south of Spain and Italy.
 
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XJR_Boy, the Noack evaporation measure is keeping the oil sample at 250C and measuring how much goes missing. It's designed to measure what happens typically in the piston ring belt area, and correlate to transfer of phosphorous and sulfur into catalysts and DPFs and the like (which poisons them). Like I mentioned earlier, chances are London to a brick that you are getting near Noack test temperatures for the bulk oil, so I really doubt it's part of your issue.
 
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Originally Posted By: Shannow
XJR_Boy, the Noack evaporation measure is keeping the oil sample at 250C and measuring how much goes missing. It's designed to measure what happens typically in the piston ring belt area, and correlate to transfer of phosphorous and sulfur into catalysts and DPFs and the like (which poisons them). Like I mentioned earlier, chances are London to a brick that you are getting near Noack test temperatures for the bulk oil, so I really doubt it's part of your issue.
Yeah, it's 250C, not 150C.
 
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Originally Posted By: XJR_Boy
I just bought a 20 litre drum of 10W50 with Mercedes rating 229.51 that's mercs highest rating its also low saps
According to Mercedes Benz there is no 10W-50 oil with MB 229.51 approval.
 
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