What this pipe for ? (1 Viewer)

[David*BJ70]

What this pipe for ?? Between exhaust and the oil filter (3B engine)

I think I've read someone redirect it to the air intake ??

Anyway, I want to redirect it because it make little smoke. (Is that little smoke is normal ?)

So any idea ?

 

[esh]

I think that's the blow-by pipe. It alleviates pressure built-up in the engine by gasses that get passed your rings during ignition.

 

[VTCruiser]

i believe eshelbyk is right.

 

[Greg_B]

Yes, that is correct, and yes, some people have directed the blowby gasses into the air intake, post filter pre intake manifold.

Some smoke it normal. Lots means worn rings/cyl wall.

Do a search of the DTLC at Birfield.com and I believe there is discussion about this.

hth's

gb

 

[baby_troupe]

We call it a breather pipe

 

[David*BJ70]

Thank Greg... it not make to much smoke !

And who know if redirect can make problem possible... make nothing... give power (wow !) ... or just less smoke ?

I will chek on birfield anyway.

 

[cruiser_guy]

I would be reluctant to reroute the blowby pipe permanently. There is always a little bit of oil that leaks out from there as well and in time that is bound to block any hose used to reroute causing problems.
If it is causing emissions testing problems then reroute it temporarily.

 

[baby_troupe]

I would be reluctant to reroute the blowby pipe permanently. There is always a little bit of oil that leaks out from there as well and in time that is bound to block any hose used to reroute causing problems.
If it is causing emissions testing problems then reroute it temporarily.

If you want to reroute it permanently, take a look at how more modern engines are set up for some tips.
They run a hose from the tappet cover to the air intake (between the air filter & the fuel injection / carby)
The oil / fumes are then able to be burned by the engine, which should actually reduce emissions anyway

 

[Greg_B]

There are a few people who have run the 3B pipe into the air intake and there has been no issues that I have heard. In fact, as mentioned the 13BT/12HT/1HZ etc all direct the blowby from the valve cover to the air intake, instead of dumping it to atmosphere. As baby-troupe says...the blowby gets recirculated and burned...not a problem at all.

As long as you have not created a U in the piping, there should no buildup of oil.

hth's

gb

 

[cruiser_guy]

As long as you have not created a U in the piping, there should no buildup of oil.

hth's

gb

That's the problem! That pipe needs to be cut real short and even then I doubt you could route it to the air cleaner without a "U".
Don't the newer engines have some sort of filter that drains the oil back to the crankcase and lets the fumes get burned?

 

[David*BJ70]

... As long as you have not created a U in the piping, there should no buildup of oil.

hth's

gb

So the first picture (sorry I'm not Picasso ) create a problem. Why ? The oily residu gonna jam the pipe ? What about a little hole on the lower point of the U

And on the seconde one, I figure to redirect all the pipe up to the air intake. For the oily residu... the gravity will make the job ?

So the question is : is the pipe should be straight UP ? If yes, this pipe should be cut and replace by a new one ?



Enjoy the drawings

 

[baby_troupe]

So the first picture (sorry I'm not Picasso ) create a problem. Why ? The oily residu gonna jam the pipe ? What about a little hole on the lower point of the U

And on the seconde one, I figure to redirect all the pipe up to the air intake. For the oily residu... the gravity will make the job ?

So the question is : is the pipe should be straight UP ? If yes, this pipe should be cut and replace by a new one ?



Enjoy the drawings

Drilling a hole at the bottom of the U would achieve 2 things (both negative).
1 it will basically do the same as not having the hose to the air intake, in that you will still be dumping on the ground & 2 it will create the opportunity for water etc to go up that openning to both the engine & the air intake.

Cut the thing off & go straight up to the air intake, that way any excess oil will run back into the engine

 

[s79bj40]

there is a huge baffle thingy on the inside of the pushrod cover that stops almost all oil from just coming out that pipe by itself. If it is spitting oil around there is a big problem. Any oil that does come out would mostly be airborne, so its no big deal re-routing to the intake.

 

[Leitrum3]

there is a huge baffle thingy on the inside of the pushrod cover that stops almost all oil from just coming out that pipe by itself. If it is spitting oil around there is a big problem. Any oil that does come out would mostly be airborne, so its no big deal re-routing to the intake.

"Spitting oil around there is a big problem"....So I have a big problem? Everything below my breather tube is coated in oil, not to mention the side plate it's mounted to is leaking oil (I have a new gasket, just need to install it). Additionally, it often looks like I have two exhausts with how much exhaust comes out of it sometimes. I've thought about re-routing like the above mentioned posts, but don't want to just fix a symptom if this is telling me something.

 

[AJAEbj42]

Holy thread revival batman! Good searching!

My drive shaft has a nice shine to it because of the breather oil vapors that blow onto it. If you have enough smoke coming out like it's a second exhaust, that might not be good. Do you have a lot of 'soot' as well? Do you have enough oil vapor coming out that it drips on the ground? That would also not be good.

Pics of what your engine bay looks like might help as well.

 

[Leitrum3]

Well, I figure that the all the rigs are 20-30+ years old already, not a lot has changed since the last time this post was current.

I'll take some photos and maybe video tonight. Not sure if video will be any good though, it's dark for a couple hours by the time I get home usually.

 

[Leitrum3]

Here is my engine bay around the breather tube. Pics are not the best since it was night and I couldn't see what I was doing.


Okay, so if I can't get the pics to show up, here is the link: Picasa Web Albums - Leit Downing - BJ60

 

[eleblanc]

Holy thread revival batman! Good searching!

LOL, i was going to say; David...WTF you have 2 cruiser and you don't know about 3B the blowby?

 

[David*BJ70]

LOL, i was going to say; David...WTF you have 2 cruiser and you don't know about 3B the blowby?

Wôôôôôô là. I wrote that in November 2004 ! I was pretty new in LC diesel at this time !

I would say: worn piston rings can do that.

Anyway, I did not see the smoke with you engine in operation but your engine bay don't look that bad.

 

[Leitrum3]

So, I'm going to give this another go since it looks like I'll be making the 2500 mile drive from Anchorage to Seattle in a month. I replaced the side cover plate gasket two months ago and nary a drop of oil out of it since (great success!!). However, now the oil dripping out of the blow by tube is even more noticeable and on a recent drive up the highway, I think I had more visible exhaust out of that tube than the exhaust! I took some better pictures now that the area is a little less like an oil slick.

Any further thoughts? Would YOU drive this thing 2500 miles through the middle of nowhere?