2.8 diesel 5l air blowing from oil filler

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godimento, Feb 5, 2:42pm
I removed the oil filler cap from my non turbo 5l with the motor idling and the air puffing out is definitely noticeable, feel like a small exhaust. Searching online tells me this is how to check for blow by but searching online also tells me this is normal? It has a couple of oil leaks but I want to make sure I am not wasting my time fixing them if they are caused by excessive crank case pressure. As far as I can tell there is no egr valve, just the tube from the valve cover to the intake.

tweake, Feb 5, 3:00pm
normal.
blow by at idle is actually worse than when under load.
inside the rocker cover is the breather system oil collector. they are known to block up a bit and cause oil leaks. can be worth pulling it apart and cleaning.

btw the 2.8 is the 3L. the 3 litre is the 5L.

godimento, Feb 5, 3:27pm
Doh, yes it is 3 litre. I just pulled the vent hose off where it goes into the valve cover with the engine idling, I could feel air coming out but feel like compared to what was coming out of the oil filler cap that maybe it should be more so I will look into it.

intrade, Feb 5, 3:37pm
as long as its air . once oil starts comming out of there then you have a problem like a runawaY Diesel. You would open oil filler pull dipstick and rip that hose off and then if it still dont stalls put your tshirt in to the air intake and underwear to stall it if its automatic. once it runs away.

tweake, Feb 5, 4:59pm
the other thing is to do the dirty trick of venting the breather pipe to air. (don;t forget to block the breather intake port)
fit a catch can to stop oil dripping out if you like.
it will run better, especially at idle because its not sucking unregulated egr all the time.

godimento, Feb 5, 8:25pm
A little oil comes out but I do not see how it possibly couldn't with the air coming out and the camshaft flicking oil everywhere. There is some oil in the intake but that is probably to be expected.

My main concern is if I do have excess crankcase pressure there is no point fixing the oil leaks but as long as the valve cover is not clogged up that should not be an issue as the pressure would just be vented into the intake?

marte, Feb 5, 8:55pm
I think it really needs ' flow' thru the engine, but at no more than the crankcase self pressurised.
You need to get rid of condensation & fuel fumes & waste oil mist.

So it needs a inlet after the MAF into the crankcase, a one way valve on that so nothing goes backwards into near the MAF.
And a outlet a fair bit downstream of the MAF just before the inlet manifold, with a one way valve on that so a sudden rush of incoming air won't pressurise the crankcase via its outlet.

So with crankcase vacuum, it will suck in fresh air from just after the MAF, and on crankcase pressure, ( and vacuum in the inlet manifold ) it will suck dirty air out of the crankcase into the inlet manifold near the inlet.

Would this be right?

tweake, Feb 5, 9:58pm
no.
no MAF of these engines. sounds like your talking petrol not old school diesel.

all diesel needs is a pipe for it to go out.

tweake, Feb 5, 10:00pm
where is the oil coming out of?

keep in mind these are 20+ year old engines, your going to get some seal/gasket failure at times.

godimento, Feb 5, 11:22pm
Sump seal and rear main. Sump seal was fixed but leaking again

franc123, Feb 6, 1:10am
Get a cylinder leakage test done. This will give you what percentage of combustion gas is actually leaking past the rings. Normally only requires glowplug removal to complete and a special air tool. If its deemed to be excessive then yes it's getting worn and increasingly difficult to keep the oil seals functioning right.

tweake, Feb 6, 11:08am
i'm going out on a limb and say get a better mechanic.

the sump doesn't have a separate gasket, its "glued" on. its the last thing that will fail due to excessive blowby.

philltauranga, Feb 6, 11:26am
In my experience transporting old machines to the wrecker, operating and repairing all sorts machines. I have found excessive blowby just pops the dipstick out if the breather is blocked.
+1 for the leakage test if you are worried if its worth repairing oil leaks, if the dipstick is the type that just slips in, I think blowby is unlikely to be the cause of them, if the breather is blocked.

intrade, Feb 6, 11:30am
rear main seal leaking . i hope they did not damage the crank .
You have to test blow-by with leak-down test . and compare each cilinder to another my money is on number 3 is bad . Then you have 2 options only. ! if it turns out you have excess blow by gas. i will rite the story of what i done in my next post. for if its pi$$ing past the rings.

intrade, Feb 6, 11:41am
Ok this is going to be half a book again and there is actually more drama had from doing stuff to well but i wont include that as it has nothing to do with how to fix your problem."if you have exess gas going past the rings"
Right i got me a direct injector the first one italian iveco and was sold one with failing engine. However i did not know this untill i had engine oil all over the diesel tank and chassi and found the oil came out the pipe venting to atmosphere= its blowing past the rings When turbo boosted under load. So in order to use it still i removed the sponge like filter in block , drilled a hole in to the oil filler cap and fitted a old heat resistant oil bottle like a funnel on top of the oil filler as back then no one did know what the word catch-can was . I drilled a hole on top and routed the crank vent in to the funnel. and driven that for 1 year like this Till i rebuilt the engine for 5000 bux chf thats like 9 grand nz To fix this problem.
Them iveco had engine wear issues and i did not know that it was normal for them to wear the boors out and that most are fubar at 200,000km
When i was driving a 1,7 fiat Diesel with 360,000km and no such problems. Expensive lesson Do research before you buy was burned in my brain due to what money was burned up back then.
i sold that thing 10 years later fro 4500 bux with the engine having about 2000km on it. i could not bring it over as it had a 4 by 2 meter box on the back and was left hand drive .

philltauranga, Feb 6, 12:11pm
A quick googly tells me the 5L has a slip in dipstick, you could do a simple test, disconnect the breather, start the engine, block the pipe. I'm willing to bet it will just pop the dipstick up a little bit to relive the pressure, this should put your mind at ease about repairing the oil leaks, because I find it unlikely they are caused by excessive blowby pressure. Most engines I have seen the dipstick tube only goes into the block not all the way down to below the oil level, so it shouldn't heave any oil out of the pipe, only air.

franc123, Feb 6, 12:20pm
Or some lardhead has had the sump off and used that hideous orange RTV to seal it back up again. I cant believe some people still use that rubbish when theres far far better sealants about from the likes of Loctite or ThreeBond.

franc123, Feb 6, 12:26pm
It's what those old L series Toyota diesels do when they're old. They just start leaking from every orifice, its unusual to see a 90's Surf or Hiace with one in it which isnt at best leaking from at least one of the oil seals, especially turbo versions at worst it looks like the whole thing had been dunked in a waste oil tank. You've got to weight up what justifies a repair which may or may not work because it will just start leaking elsewhere. Unless its chomping through oil at a great rate and/or blue smoking from the exhaust it's often best to leave well alone!

philltauranga, Feb 6, 12:32pm
Sound like a Detroit truck engine, they mark their territory like a dog, pissing everywhere.

shakespeare6, Feb 6, 8:16pm
Fix the oil leak and drive it. Forget about the rest

godimento, Feb 9, 2:04pm
Thanks, I am guessing to leakdown test a diesel you need a special tester as the petrol ones only go to about 100 psi?

Also does the fact the sump and rear main leak mean I should do them both at the same time or can I just do the sump with new oil first? As I understand to do the rear main they might need to pull the plate/cover around it off and the bottom of it is basically sealed to the sump. So if I only do the sump first here is a chance it could leak again when the remove the cover for the rear main?

intrade, Feb 9, 4:50pm
leakdown is not compression test. You feed air in the closed cilinder and listen where the air blows and how much is loast should be the same as petrol Diesel is more tight or should be.
https://www.youtube.com/watch?v=tCShoS0XkPM

intrade, Feb 9, 4:57pm
if the rear main seal leaks then its gearbox off and flywheel off to get to that seal to replace. Its why you would replace it when doing the clutch So you dont have the whole labour again plus some as what it is for doing the clutch
on auto you would change the torque converter seal in box as that can also only be done with gearbox off.

intrade, Feb 9, 5:01pm
How easy does this cold start as with a bad bores you would have longer crank times.
leakdown would be to buy the kit for glowplugs or modifie drill and weld airline on a glowplug to feed air via glowplug holes in to cilinder for leakdown instead of sparkplug holes.

godimento, Feb 10, 8:23am
Cold start is pretty much instant, has a little idle shake, idle speed looks ok.