[mtnbiktn]

I just bought this 1998 van that has 88,000 miles with stock PS and took it in to Ford to diagnose a miss. They checked all cylinders and say the compression is great and replaced two injectors, however they are puzzled about the amount of blowbye. The technician drove it and was pleased with the performance but could not answer the blowbye question. I do not know any of the history on this van. It is not blowing smoke rings out the oil fill cap, but they seem to think it is an above normal amount of blowbye.

Any ideas?

 

[Patrick Feeley]

Did they actually measure it? I think there is actually a procedure to do so. Unless they do it, they are only speculating. Cheers!

 

[mtnbiktn]

They told me they checked the compression on all cylinders and it was good. ( what good is, they didn't say ).

What do you think?

 

[Patrick Feeley]

There is a procedure to test for excessive crankcase pressure (tell them to see PCED Section 14A, Performance Diagnostic Procedure 13). Cheers!

 

[brahamfireman]

Do you know this procedure??? I was just gunna post cuz I want to know how to test mine.


Diesel Rod

 

[Patrick Feeley]

I've never had it done or done one, but it is detailed in my Powertrain Control and Emissions Diagnosis manual. Some special tools required. Cheers!

 

[F250Jockey]

I don't know the details, but I've heard Ford uses a device that has a oil cap adapter with a tube attached to a calibrated hydrometer type gauge. Apparently, your blowby will push the fluid in the hydrometer up in a calibrated tube. There is a certain level that the fluid can go up to before you are considered having too much blowby.

I've seen sevearl of these types of hydrometers. If someone had the details of the setup and calibration/parameters they use, one of these testers would be inexpensive, and easy to make. /ubbthreads/images/graemlins/smokin.gif

 

[mtnbiktn]

I did talk to the Ford tech today, and he was aware of the test. His thinking was since the van ran so well and the compression was so good, he would not worry about it. If I did have the test done, it may or may not detect too much blowby. If it had too much, he says the test would not show where the excess blowby is coming from. According to him, the 1997 and 1998 models had very few problems and for me to just go drive it and not worry about it. I think I will read this forum and make some changes like a bypass oil filter, etc. and just use it.

 

[302boss]

Good idea. I see someone selling a crankcase hose bypass kit for the superduty's. Is that what your considering?

 

[swh22]

If that's how they are measuring it make sure the crankcase vent isn't plugged up.

 

[Gone Fishen]

I do this test all the time however I have never done this on a Powerstroke engine. I do this test with a 'manometer'. It is a plastic tube in a U shape and it has a colored liquid [water] in it. The tube has a ruler [like a tape measure] on the area between the 2 tubes. When the engine is tested at FULL LOAD the pressure pushes the water down 1 side and up the other. The combined readings are the results. Example a Series 60 on the dyno having a side of 2" and the other side of 2" is a combined reading of 4". The amount of 'inches of water' as we call it is compared to max spec's and the owner is informed as such. Hope this explaines the procedure. You could have a plugged muffler,bent/kinked tailpipe, plugged catalytic convertor. Things like this will cause a vent to 'push out vapor'. Hope this helps.

 

[fourhatz]

The Powerstroke is tested at full throttle no load and should be below 6" H2O.

With good compression but visible blowby I would want a reading of the blowby and if it was below 2" than I would suspect water in the oil and you are seeing steam instead of blowby.

 

[brahamfireman]

most likely what he was seeing, both of mine spit out a fair amount of whispy steam looking smoke, I never gave it a though, use the ol' truck still runs, dont go looking problems theory. /ubbthreads/images/graemlins/wink.gif


Diesel Rod

 

[302boss]

Yes, never checked when mileage was low but have seen 200K trucks that "puff" out the oil cap a good bit. Seems the PSD's make alot of blowby and or vapors. It maybe the dealer just wasn't up on the PSD in this case /ubbthreads/images/graemlins/shrug.gif