If you want to eliminate the cyclone you could always disconnect the pipe from cyclone to intake pipe and route in into a catch bottle (also blank the intake pipe) and give it a try. If it still smokes then you know the cyclone isn't the main cause. You can also remove the pipe from the intercooler to intake manifold and give it a quick try (don't drive around as it will be like driving a NA (and you also won't have a working air filter). If it still smokes then it is an 'internal' oil leak (piston rings / valve guide seals), if it doesn't and the air from the intercooler is oily then it will be turbo or residual oil in the I/C
300 Tdi Rebuild
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Excellent! I definitely need to get geared up to try these tests. There's certainly a lot of oil coming through the turbo, intercooler and in to the inlet manifold. I can see it in the pipes. What I don't know is if that is the only way the oil is being used up. The first thing I'll try is removing the I/C pipe from the inlet manifold. That should have an immediate effect. Then I'll try catching the oil out of the cyclone to see how much is coming through. Great tests. Thanks!
jamesmartin
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theres allways oil in the induction side in that hoses will seem wet, to much is hard to say ,heavy breathing would suggest bores and ringsExcellent! I definitely need to get geared up to try these tests. There's certainly a lot of oil coming through the turbo, intercooler and in to the inlet manifold. I can see it in the pipes. What I don't know is if that is the only way the oil is being used up. The first thing I'll try is removing the I/C pipe from the inlet manifold. That should have an immediate effect. Then I'll try catching the oil out of the cyclone to see how much is coming through. Great tests. Thanks!
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I'll be horrified if that's the case, James. For obvious reasons! What could I have done wrong for the bores and rings to be leaking so badly? If that's what it turns out to be.
The compression tester should arrive by Tuesday, so that will help indicate the issue.
jamesmartin
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not you the the quality of honing,if its put on too lightly it doesnt take out the boring finish and is polished off
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Did you look at the picture I posted. Do you think it was too light?
jamesmartin
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its hard to say from the pic but i wouldnt say id be impressed,if you think that when a bore is cut you end up with a very fine screw thread type surface when you hone apart from cross hatch angle its best to take out 2 thou to ensure that screw thread surface is completely removed and raw block honed ,you need to check simple things first ie turbo but a litre in a few hundred miles is some useage, you expect some pressurisation while bores run in but youve done quite a few
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I've done about 850 miles in it since it was first fired up. Should be run in by now.
The turbo is newly reconditioned, so I presume it's ok.
What do you think of the honing devices you can get that attach to a drill?
jamesmartin
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you can never presume anything once youve built enough stuff you find out that ,they are ok if you get the 45 degree angle ie speed of the drill and up/down rhythm right and do it enough ie a complete surface rather than just a few scratches
if it comes to that you will only know when head is off
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OK, so if it comes to having to take the head off, then I presume I'll see very little sign of the honing marks- if that is the problem?
jamesmartin
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yes there will still be some but boring surface will be noticeable, id be surprised if it were valve guides tappet setting is possible
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But the boring surface wasn't noticeable before, was it?
I checked the tappet settings about 80 miles after first start up. I'll check them again though, worth checking the simple things several times!
I wonder if the machine shop did a good job of grinding the valves in to the seats! Could this be another issue?
jamesmartin
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you tend to hear poor seating valves as an echo in manifolds, its not so easy from pics but its not uncommon for macninists to bore to size the put a quick hone on,when whats needed is boring to size minus a thou or three to hone to finished sizeBut the boring surface wasn't noticeable before, was it?
I checked the tappet settings about 80 miles after first start up. I'll check them again though, worth checking the simple things several times!
I wonder if the machine shop did a good job of grinding the valves in to the seats! Could this be another issue?
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Hmmm..........that could be problematic. If I do end up honing the bores myself, will taking off another couple of thou in the process cause me other problems with the rings fitting properly? ie will the bores then be oversized for the pistons and rings?
jamesmartin
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you wouldnt take a couple of thou off and slightly bigger but a good surface is better than correct and poor,
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Ok, doing a bit of home honing could be a plan of action then, depending on what crops up with the compression tester etc.
Cheers, James.
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Well, got home tonight and thought I'd try a few tests. The Mrs had just beaten me home, so the engine was hot. Started it up, looking down the side to see the exhaust give it a few loud blats from the FIP. A little dark smoke visible on high revs. Took the top hose off from I/C to inlet manifold. Engine sounded like a lion with a sore throat. Blasted it from the FIP again and there was even more smoke from the exhaust. I put the inlet manifold pipe back on and took the cyclone breather to air intake pipe of the cyclone. Revved it hard to see how much oil came out of the cyclone and nothing for the short time I tested it. I'm not sure what that tells me yet exactly! Maybe the amount of oil I have in the I/C pipework is normal and I'm not burning oil that is coming via the cyclone and through the turbo?
Anyone have a non smoking engine, that has the same amount of oil in their I/C pipes?
The compression tester arrived today. Amazon said it would, but I still didn't think it would get here until Tuesday. I work late on Mondays and Tuesdays, so earliest I might do a compression test is Wednesday. Forecast is rain though.
Does that trick of doing a compression test and then putting some engine oil in and doing it again, really work to show if ring seal is dodgy?
Anyone have a non smoking engine, that has the same amount of oil in their I/C pipes?
The compression tester arrived today. Amazon said it would, but I still didn't think it would get here until Tuesday. I work late on Mondays and Tuesdays, so earliest I might do a compression test is Wednesday. Forecast is rain though.
Does that trick of doing a compression test and then putting some engine oil in and doing it again, really work to show if ring seal is dodgy?
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My 300Tdi in our 1988 is smoke free unless you hammer it up hill - and then it is the usual black smoke and even then only a haze and not clouds of soot....and I have traces of oil in my intake hoses.
A teaspoon of oil down the bore does work to seal the rings on a petrol - never done it on a diesel.....I can only imagine it would do the same thing!
A teaspoon of oil down the bore does work to seal the rings on a petrol - never done it on a diesel.....I can only imagine it would do the same thing!
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Cheers, Saint. Appreciate that. It's probably a while since you looked in, but can you remember if the amount of oil in your intercooler pipe work is a similar amount to mine?
I'm going to wait until Saturday to do the compression tests. I think I'm having to build myself up to it
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Oil amount is similar from memory, will have another look - but may not be until the weekend before I get the chance....will report back.
