excessive pcv blow-by? (solved)

[adam_c]

This is my first diesel car, so I'm not sure if this oil blow-by is too much or normal.  The car is a 1986 Volvo 740 Turbo-Diesel with the VolksWagen LT35 (Volvo called it the D24T).  If you're not familiar with the engine, it is an in-line 6-cyl. indirect injection non-intercooled turbo-diesel with EGR supposedly similar to a lot of 4-cyl. diesels that VW put in their cars :?:

Here is a pic of the engine.  More pics of engine and car are at
http://www.k-jet.org/mycar_diesel.html



So anyway, I'm getting a lot of blue smoke out of the exhaust, at all times, not just when starting or warming up.  At first I was like "Oh no, my rings/valve guides/turbo bearing seal are shot, I'm doomed."  But I took the PCV hose off (marked #1 in this labelled pic, below) and the thing is completely lined with oil.  Lots of it.  Dripping everywhere.  



If I put my finger in the rubber tube (#1) up to the first knuckle, it comes out soaked in oil, with oil dripping off my finger. In fact, you can see some oil that has leaked out at the metal pipe and down onto the manifold.

Like I said, my first diesel, so I don't know if this much blow-by is normal or if something is plugged up or whatnot.  I was thinking I should do the Wingnut CCV system 3.0 ( http://forums.tdiclub.com/showthread.php?t=121576 ) ? Will that help?  I don't want to just open it to the atmosphere, it would drip oil everywhere.

The engine is in good running condition otherwise, and has lots of power.  If I put this in the wrong section, sorry...it is a VW motor though  P.S. Does anyone know what the thing marked #3 is? I have no idea.  :oops:

Thanks a ton...or 2 for this car  :wink:
-Adam

[adam_c]

well no one responded so I just decided to wing it.  I found a solution that worked out very well in case anyone cares.  This is copied from my post on forums.turbobricks.com

Well, I decided to just wing it and make my own PCV filter/catch can for my 740 Turbodiesel.  What I did was install a particulate filter for an air compressor in the line.  I think it's far superior to the oil catch can setup. Here are the pictures.









Zip-ties FTW!

Filter stats:

Manufacturer:  Arrow Pneumatics, Inc
Retailer: Northwest Compressor
Model: Series F370W (aka F37W) Particulate Filter
Filter: EK37 - 40 Micron Sintered Bronze Element
Features: Re-useable element (clean in solvent) - oil sight to see how full it is - drain cock at bottom of bowl for easy draining. 3/4 inch NPT fittings.

I also bought two 3/4 inch NPT hose nipples and some hose.  The filter apparatus cost $64.10, and with the fittings and hose, it was a total of about $78.00 (the fittings were $4 each).  After I installed it I wished I had bought more hose, since I didn't have much to work with and I ended up needing more than the 4 ft. that I bought. I might go back later and get some more hose to mount the filter farther away from the turbo.

I would say the amount of blue smoke from the exhaust has been reduced from a lot all the time (visibile in rear view mirror) to no blue smoke at all, so it was definitely worth it.

For more info on this project, see my webpage;

http://www.k-jet.org/mycar_diesel.html

[Darkness_is_spreading]

The catch can approach is a pain in the arse,  I may be able to work around it by just cleaning the NA valve cover mesh screen.....

Catch can, was a bigger pain in the ass than having oil shoot out the dipstick, the tiny oil droplets covered the entire engine bay in oil, but the motor got to the point of being impossible to start, so I'm going to be bidding on a compression tester to see if shes dead, and ready for a mechanical NA swap

[jtanguay]

should probably look into some totalseal rings

[adam_c]

The catch can approach is a pain in the arse,  I may be able to work around it by just cleaning the NA valve cover mesh screen.....

Are you serious? This was probably one of the easiest mods I've ever done.

[houseofdiesel]

I hope that system does not restrict the flow...otherwise your going to blow your crank seals and other oil seals when the excessive blow by finds a way out of the engine. Very common on Mercedes diesels when lots of blowby to fix one seal only to have another leak right after from the crankcase pressure. Your only fix is rebuilding it...
Greg

[adam_c]

I don't think restriction of airflow with this thing will be a problem.  I found the flow rating on the arrow pneumatics website: 245 std. cubic feet per minute.  That's a lot of air flow.

[nkb]

I don't think restriction of airflow with this thing will be a problem.  I found the flow rating on the arrow pneumatics website: 245 std. cubic feet per minute.  That's a lot of air flow.

245 cfm at what psi tho... you could get alot of flow thru a pin hole with enough pressure. like injectors, i have a set of 445cc/min injectors at 45psi in one of my cars but less pressure, less flow.
on the other hand if you can freely blow thru the catch can and its working for you than its a great temp fix!

[Darkness_is_spreading]

Although if not vented properly, eng oil covers everything.....

[adam_c]

245 cfm at what psi tho...

sorry, i should have said that std. cubic feet per minute (SCFM) means the following conditions are present:

psi = 14.7 PSIA (aka absolute pressure which is gauge pressure + atmospheric pressure)
temp= 68°F
relative humidity = 0%

so yeah 245 scfm is a lot of air flow i think.