evanmc Posted January 21, 2018 Share Posted January 21, 2018 1985 110 2.5NA Please see the attached movie. Smoke and oil are coming through the middle nut in the rocker cover. OK, it was probably doing this before -- the rocker cover was completely covered in old oil before I cleaned it up, but now I'm starting to get smoke in the passenger compartment. Is this excessive blow-by? Worn rings? I don't want to just cover up the symptoms by putting rubber gasket on the nut to keep the oil from coming out. Thanks for any pointers. -Evan- rocker-cover.mov Quote Link to comment Share on other sites More sharing options...
monkie Posted January 21, 2018 Share Posted January 21, 2018 it does look like excessive blow-by to me. This could be caused by a few things including worn bore/rings as you suggest, or heavily glazed bores or stuck rings. But from what you say it seems to have suddenly started doing this, which in mind points towards a head gasket leak. Quote Link to comment Share on other sites More sharing options...
Cchase Posted January 22, 2018 Share Posted January 22, 2018 Evan, Do you have a breather hose from the oil filer cap to the 'cyclone' breather? I was having a lot of oil leaking from the same stud hole and put a rubber o-ring and washer underneath the nut. This stopped the oil coming out. I did not have smoke however, but do have the crankcase breather hose attached. My engine is newly rebuilt. As it is becoming worn in I am getting less of the positive crankcase pressure. A picture of your whole engine bay would be helpful. Quote Link to comment Share on other sites More sharing options...
evanmc Posted January 22, 2018 Author Share Posted January 22, 2018 I should have been more specific above... I was seeing a bit of this before (slight escape of smoke), but it certainly wasn't visibly spewing oil out. This is much worse after taking things apart to replace the water inlet gasket -- seemed like I would never get it started again. Perhaps the excessive cranking pushed things over the edge? Can I replace the rings with the engine in place? I'll have to remove the head anyway, so replacing the gasket won't be much more work. Yes, I do have a breather tube from the filler cap to the cyclone. -Evan- Quote Link to comment Share on other sites More sharing options...
monkie Posted January 22, 2018 Share Posted January 22, 2018 1 hour ago, evanmc said: This is much worse after taking things apart to replace the water inlet gasket -- seemed like I would never get it started again. Perhaps the excessive cranking pushed things over the edge? I'm not sure what you mean by "water inlet gasket". Do you mean the thermostat housing (front of the engine protruding on the head) gasket? Cranking the engine over shouldn't cause this problem, what else did you disturb while doing this job? 1 hour ago, evanmc said: Can I replace the rings with the engine in place? I'll have to remove the head anyway, so replacing the gasket won't be much more work. You can replace rings with the engine in place, but you don't know this is the problem at this point. I think you need to take the head off and look carefully at the cylinder head gasket, pistons and bores. Are you able to borrow a compression tester (for diesel engines) to do a compression check before you do anything else? Quote Link to comment Share on other sites More sharing options...
evanmc Posted January 22, 2018 Author Share Posted January 22, 2018 I replaced this gasket. https://www.lrdirect.com/ERR1607-Gasket-Water-Inlet-2.25-2.5Pddt2T/ I disassembled quite a bit (removing the timing case to get at that gasket), but nothing that would seem to have an impact here. I'll get a compression tester (assuming I can find the right size glow plug adapter) and test. -Evan- Quote Link to comment Share on other sites More sharing options...
monkie Posted January 22, 2018 Share Posted January 22, 2018 1 hour ago, evanmc said: I replaced this gasket. Okay, now I see. I don't think this is anything to do with the cause of the high crank pressure. Presumably you changed this gasket as it was leaking, so do you have high pressure in the cooling system? I've had a head gasket fail causing both high crank pressure and a hiss when I took off the coolant cap when cold. 1 hour ago, evanmc said: I'll get a compression tester (assuming I can find the right size glow plug adapter) and test. Ensure the one you borrow is suitable for the much higher compression in diesel engines, the most easily available testers are often only designed for the lower pressures found in petrol engines. Quote Link to comment Share on other sites More sharing options...
evanmc Posted January 27, 2018 Author Share Posted January 27, 2018 Finally had the chance for a compression test: 420PSI, 420PSI, 440PSI, 240PSI. -Evan- Quote Link to comment Share on other sites More sharing options...
western Posted January 27, 2018 Share Posted January 27, 2018 is that cylinders in order 1,2,3.4 from the front of the engine, if so No4 is well down. compared to the other 3. Quote Link to comment Share on other sites More sharing options...
evanmc Posted January 27, 2018 Author Share Posted January 27, 2018 Yes, 1-4 from the front of the engine. I'll check to see what is the expected values -- a 23:1 engine should have 338 PSI at sea level? Seems low, so I'm sure I'm thinking about this wrong. 1 Quote Link to comment Share on other sites More sharing options...
monkie Posted January 28, 2018 Share Posted January 28, 2018 Around 420 is what I would expect. So I think it shows your problem is a head gasket leak most probably into the space in the block for the push rods hence your high crank case pressure. Quote Link to comment Share on other sites More sharing options...
evanmc Posted February 11, 2018 Author Share Posted February 11, 2018 Finally got time to remove the head off. Sure enough, I see this on the #4 cylinder. 1 Quote Link to comment Share on other sites More sharing options...
monkie Posted February 12, 2018 Share Posted February 12, 2018 Great result. It should start and perform better once fixed. Quote Link to comment Share on other sites More sharing options...
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