CCV Breather hose catch can

[xjtrailrider]

Long story short; Our 89 MJ with 170k on the clock, one "easy over" and one flop(stayed running for 5 min upside down LOL!) is starting to get oil into the air tube/intake.

I need to slow the bleeding down while I look for a replacement motor.

Do I need a catch can on both lines or just the front. I realize there is probably oil being sucked into the orifice line as well.

I have done the valve cover mod so we can rule that quick fix out.

 

[O-Gauge Steamer]

A catch can sits in the line between the rear elbow and the intake manifold. The front is the air intake port for the PCV system.

I run a Moroso Oil/Air Separator part on my XJ so as to be able to remove those pesky oil vapours from the PCV system.

IMO, clean out the line to the front elbow and make sure the system is actually drawing air. An engine would have to be very sad to vent out of the front as long as the rear vent is operating properly.

 

[xjtrailrider]

A catch can sits in the line between the rear elbow and the intake manifold. The front is the air intake port for the PCV system.

I run a Moroso Oil/Air Separator part on my XJ so as to be able to remove those pesky oil vapours from the PCV system.

IMO, clean out the line to the front elbow and make sure the system is actually drawing air. An engine would have to be very sad to vent out of the front as long as the rear vent is operating properly.

This engine is sad LOL! Running upside down for 5 min or more was not good for it.

 

[joe_peters]

Search--Cruiser54 has posted up a mod for trimming inside of the VC on the Renix 4.0 that helps with picking up too much oil into the CCV.

 

[xjtrailrider]

Search--Cruiser54 has posted up a mod for trimming inside of the VC on the Renix 4.0 that helps with picking up too much oil into the CCV.

Ive done that, thanks Joe.

I have a lot of blow by with this engine. It may be worse than just ring wear but it runs strong and smooth. I'm looking for another engine now.

 

[MoFo]

Why not just put a set of rings in the engine you have?

 

[O-Gauge Steamer]

He can't just pop in a new set of rings. If it is blowing by as bad as he indicates then the bores are shot and it will require a rebuild that includes the cylinders to be bored. The cylinders wear with time and that causes the rings to leak more than they do when new.

All engine have blow by. That is the reason behind the Positive Crankcase Ventilation in the first place. None of you, OK most of you, do not remember "road tubes" which dumped the crankcase pressure directly out into the atmosphere.

If the OP were to re-ring the pistons, most likely they would never seal. Also, it is possible that the compression would be so low as to make even starting it problematical.

 

[xjtrailrider]

He can't just pop in a new set of rings. If it is blowing by as bad as he indicates then the bores are shot and it will require a rebuild that includes the cylinders to be bored. The cylinders wear with time and that causes the rings to leak more than they do when new.

All engine have blow by. That is the reason behind the Positive Crankcase Ventilation in the first place. None of you, OK most of you, do not remember "road tubes" which dumped the crankcase pressure directly out into the atmosphere.

If the OP were to re-ring the pistons, most likely they would never seal. Also, it is possible that the compression would be so low as to make even starting it problematical.

Correct! I plan dropping in another motor while I go through this one. All 4.0's are rebuild able if they do not have a hole in the block! The one in my XJ had #3/#4 pistons melted completly down to 3/4 of the pistons were left. The cylinders had severe scaring and I thought it would never run again. That was 20,000 trouble free miles ago. I bored it .040 and decked.020/milled .020. Its a damn strong runner! This engine has heart as well but its needs surgery!

 

[O-Gauge Steamer]

You are correct Sir.

As long as the block is free from extra ventilation locations and cracks, you can rebuild until you run out of room to bore the cylinders. Then, you sleeve the block and start all over again.

Personally, I always have both the block and the head magnafluxed to ensure the parts are in good nick for the rebuild. A small bit of paranoia is a good thing...

 

[MT Mike]

I've been running one of these for 6+ months. It works well enough and the price is right. YMMV.

 

[joe_peters]

I've been running one of these for 6+ months. It works well enough and the price is right. YMMV.

Super deal on that buy-it-now price. :cheers:

 

[xjtrailrider]

I've been running one of these for 6+ months. It works well enough and the price is right. YMMV.

Nice!

 

[O-Gauge Steamer]

As long as there is something in the can for the oil to coalesce around, you can't beat the price. Having a site gauge is a nice touch.

 

[xjtrailrider]

Most of my oil is coming from the front tube? The rear tube is not clogged either. Should I put one of these on each tube?

 

[MT Mike]

Most of my oil is coming from the front tube? The rear tube is not clogged either. Should I put one of these on each tube?

My rear tube is clear also, I have my front tube run into the catch can and then from the catch can to the air box tube.

 

[xjtrailrider]

My rear tube is clear also, I have my front tube run into the catch can and then from the catch can to the air box tube.

That is what I will do as well then.

 

[xjtrailrider]

I finally got around to fixing this today. I ordered a catch can from the above link. The can fits nice.

 

[MT Mike]

Good mounting location! :thumbup: I still have the stock airbox so I just put a self tapper in the lid through the bracket to hold mine in place. Mine only needs to make it through the winter while I build another engine.

 

[xjtrailrider]

Well the catch can has made the problem worse. Now its blowing oil out all over the place. Could I have something hooked up wrong with the can? It acts like the breather is no longer breathing.

 

[MT Mike]

Looks like your catch can is hooked up right to me. The only difference I can see is I ditched the cheesy blue vinyl tubing and went with quality breather tubing from the local auto parts store.