Road draft tube

[crashnzuk]

I was doing some checks on my dad's truck today, one of his compaints is that it uses oil. The intake was VERY wet with oil and I mentioned the talk of a RDT and that all of the cool kids were doing it. He said let's try it. His truck has an ATS turbo kit on it, so I just cut his hard tube that was connecting the CDR to the intake housing and put a hose on it and ran it down the bell to the side of the trans. I then capped the nipple on the intake housing. Having looked inside the CDR, it doesn't look like oil will make its way out since there is no "suction", so hopefully it won't drip on the ground. I did notice there is a fair amount of blowby coming from the tube at idle. Hopefully this isn't a bad sign for his engine, it is a 50k mile reman. He was hoping that this mod would curtail his exhaust smoke, but that seems unaffected. Just thought I'd share. I didn't take any pics either, I'm a bad interweb poster
Travis..

 

[Diesel Max]

If the intake is that wet and you are seeing that much blowby, I would be willing to bet you will see oil dripping out of that RDT as soon as you drive it much. Have you tried changing the CDR ?? Sometimes they get gummed up and quit working properly but what what your describing seems to be more then normal blowby due the oil consumption issue.

All these trucks use some oil. I had one 7.3 that used a quart every couple hundred miles, turned out that engine was "dusted". The truck I have now uses about 1/2 quart every 3K miles.

 

[crashnzuk]

We'll see how the oil dripping goes, this is 100% reverseable. I don't know how much oil it's using, I don't recall him saying anything about it really during his cross-country trip this spring, but now he is saying he's having to add some oil
Travis..

 

[Diesel Max]

You should find out many miles he is going in between adding oil. If the truck is not leaking oil anywhere and it is burning it, knowing how much oil your burning might give an indication of how bad the blowby is.

 

[flareside_thun]

I have one question, how is installing an RDT and bypassing the CDR going to solve the oil consumption problem?

 

[Diesel Max]

I have one question, how is installing an RDT and bypassing the CDR going to solve the oil consumption problem?

There's a theory out there that when running through the CDR the "suction" will pull more "oil mist" or blowby through the CDR and into the intake.

IMHO there will be no improvement in oil consumption or blowby by running a RDT, however it will keep the intake cleaner and free from oil.

 

[CDX825]

One thing thats been mentioned here before is these trucks seem to like being run a quart low and Ive noticed this with my truck.

Before I knew this I would try to keep it at the full mark all the time and it used allot of oil. They seem to use that first quart very quickly then after that oil usage goes down.

The oil was also meant to be checked hot so if your checking it cold it will show lower and you could be overfilling it.

 

[crashnzuk]

I have one question, how is installing an RDT and bypassing the CDR going to solve the oil consumption problem?

There's a theory out there that when running through the CDR the "suction" will pull more "oil mist" or blowby through the CDR and into the intake.

IMHO there will be no improvement in oil consumption or blowby by running a RDT, however it will keep the intake cleaner and free from oil.

^^ What he said. I don't know if it will help with oil usage or not. I looked inside the valve cover and there is a baffle under the CDR, so between that and the way the CDR is constructed I can't believe too much oil could find it's way out without assistance. Who knows, might be just as bad but it is worth a try and is reversable. I will have to ask him exactly how much oil he's having to add. I have a very finite number of days to work on his truck since he rarely stays very long, so I'd rather try something than do nothing.
Travis..

 

[idi traveler]

If the CDR is not venting properly it can increase crankcase pressure and cause increased oil leaks and oil consumption. I don't know how much crankcase pressure it would take to blow out the CDR but I've seen vent systems in gas and diesels cause all kind of problems.

 

[dansvan]

Oil seal on the turbo may be bad. It would account for the smoke and the wet intake.

 

[crashnzuk]

^^I don't think that's the case, the whole pipe leading from the CDR was oily. I'm gonna have the truck for the next week to 10 days-ish, so I'll put some miles on it and see how it is. I checked the oil today and found that it is ok. He just misread the dipstick when he put fuel in it at his last stop.
Travis..