blowby and engine mods

[jimfoo]

Several things going on here, #1 is blowby. The engine was rebuilt less that 1 year ago, but has gotten hot a lot. When a head gasket fails, can gasses also get into the oil passages or is it usually just water passages? Due to battery fumes eating through my air intake hose, unknown quantities of dirt/dust have been ingested by the engine, so the cylinders, rings and pistons may have the crap scraped out of them. If this is the case, how hard are oversize AAZ pistons to find? If very hard, can I get TDI oversize pistons and a TDI head and put it on my AAZ block or would I need a TDI crank and rods as well if they will fit? I know I could reline it as well, but if the pistons are really bad, I know the stock IDI's are expensive and hard to find as well.
To run a AAZ pump as an M-TDI pump what needs to be changed, just the camplate or more than that? Or can my IDI pump and a TDI pump be melded as an M-TDI pump?
Sorry, but I didn't know if I should post this in troubleshooting, IDI, TDI or what as it touches all topics.

[jtanguay]

thinking of running an m-TDI now?  :twisted:

definitely invest in some total seal rings.  i have yet to test mine out, but everyone i know who has them speaks highly of their ability to eliminate blowby.

just a few extra little benefits would be better cold starting from no ring end gap (more compression) and better economy from no blowby.

i'm not sure if the AAZ block could be converted to a TDI, but the 1Z block is VERY similar to an AAZ.  the tdi pistons have these domes in them that reduce the CR, so it wouldn't work with normal AAZ head & pump.

i just need to gather a head gasket and some coolant hoses and get my injectors done.  then i can assemble the motor!  not looking forward to getting the turbo hooked up with the manual vane control, but it will be a nice challenge that i think i'll be able to handle.

and for your initial question.  yes gasses can get into oil passages!  but the pressure is mostly bled back into the engine through the vent system.  1.9's have that nice sump vent to help bring the gases back to the engine, but on older 1.6's they either have to go through the piston rings, or back through an oil port, or even through the dipstick tube! (mine keeps pushing out  :?  :lol: )

[jimfoo]

I would buy a TDI head if I went that route as I know the IDI wouldn't work.
I also if going M-TDI might help my temp problems due to it's greater efficiency. I do have Total Seal rings right now, and I had no blowby, which is why I was wondering about gasses getting into the oil passages, but if enough dirt got in the engine, I can see gasses getting by the rings if they and the cylinders are all scratched up. I just need to get my other car drivable so I can start looking at this one.

[jtanguay]

already have total seals and blowby issues.. uh oh.  did you check for cylinder ovaling? any honing before installing the rings?

[jimfoo]

I don't think it is the rings fault. I also had a leak on an oil line that I didn't notice until I had about no pressure due to lack of oil. This was on a long trip, so I don't think that helped matters any.

[jimfoo]

Guess I'll be finding out what the problems were as the engine crapped out on a trip. At first it just got a little louder, then I was getting smoke inside the car, and the engine soon got very loud metallic knocking noises. I stopped and it was pouring smoke out the exhaust. Oil was dripping from the air hose going into the turbo, onto the exhaust manifold. It must have been coming from blow by. I drove slowly to the nearest town, but the water temp was up and EGT would easily get to 1500 or above with not much throttle. Boost was about normal, but power was way down. When I got to the town, the oil pressure was very low. I was afraid it wouldn't start again, so I tried to put oil in with it running, but I bet there were almost more gasses coming out the valve cover than coming out the exhaust. Also by this time the smoke was absolutely terrible, but looked more white than anything. The clanking sound was so bad I decided we weren't going anywhere.
 I had a few friends tow me, and finally got home today. As soon as the garage is clean enough and the engine compartment washed, I will start tearing things apart. I have no idea what is wrong, but I'm sure it will be apparent.

[jtanguay]

yea that is total crap.  sorry to hear man  take pics though!

[mtnsammy]

Sounds the same as mine. I am still parking it to see if I can find out what happened. I have white smoke out the exhaust all the time, more throttle more smoke. I know it is not fuel cuz I can turn up the power screw and get it real black.

The only thing that has happened is my kid rear ended a van with the rig. No body damage but I hear a slight knocking and the smoke. Battery was knocked loose, motor mounts both snapped, but no external mechanical damage. Car runs well with no overheating issues. Smoke has always been a gradual issue but I think the collision may have increased it some??

Let me know jimfoo what you find inside.

[jimfoo]

Bad bad stuff! See http://vwdiesel.net/phpBB/viewtopic.php?t=11337
I'm thinking mine died due to excessive oil in the cylinders possibly, not enough to hydrolock, but enough to cause enough pressure to deform the head enough for the cup to get loose and hammer the piston to death. That or a ring broke, breaking the piston, hammering the cup