New invention, old problem...

xj4play · 03-14-2005, 12:44 PM

In my continuing futile efforts to keep the oil on the inside of the engine, I finally gave up trying to thwart the blow-by monster. Okay damn it, if you need to throw my oil out of the crankcase, at least I'm gonna tell you where to throw it!!

Sooo, I created a catch can for the blow-by residue to land in. This will work on '87-'90 4.0's, fitted with a cone-type air filter (airbox removed).

I went to Lowes, bought an empty quart-sized paint can, a couple of 3/8" right angle brass hose fittings, a 1/2" copper tubing elbow, a 3/8" straight hose fitting and a length of 3/8" hose. Also needed are 1 grommet (brand: HELP! Part # 42059) and 1 APC Breather filter, both available from Advance Auto Parts.

First, drill two 1/2" holes in the sides of the can toward the top lip, opposite each other. Install the right angle fittings in the holes by soldering - one with the nipple facing straight up, and the other angled at 45 degrees.

Next, solder the straight hose fitting into one end of the elbow (a little grinding may have to be done to get it to fit). Install the grommet in the front hole of the valve cover. Fit one end of the hose to the straight fitting and insert the other end of the hose on the angled fitting of the can. Insert the other end of the elbow into the new grommet on the valve cover. I sealed the grommet and elbow junction with Permatex.

Now install the breather filter on the other fitting of the can. Sit the can on the inner fender where the old airbox used to be.

I painted the assembly with Rustoleum hammered black paint. For now, it is just sitting on the inner fender, but I plan to mount it and install a petcock to drain it. To empty it right now, I have to disconnect it and pop the lid off to dump it out. Yeah, it's a bandaid, but at least it keeps the engine bay dry.

I'll post pix as soon as I can get some shots of it.

ddoffroad · 03-14-2005, 02:37 PM

thats awesome...im looking to do something like that on my 93 ZJ. Do you have any pics of that assembly.....?

Thanks,
DDO

**BeachinXJ** · 03-14-2005, 02:49 PM

I wonder if you could just dump the oil back in?

Nice idea.

thackney · 03-14-2005, 03:42 PM

Nice write up. Can't wait to see the pictures of it.

Dvs_Lance · 03-14-2005, 03:44 PM

I thought I had a blow-by problem and was going through air filters like crazy. Replaced the lines coming off the valve cover, and it hasn't gotten oil on a airfilter since. Just thought you might like to know

ssnsltd · 03-14-2005, 08:37 PM

I did the same thing with a plastic can myself before I rebuilt the engine.

FYI on Blow-by.
On all three of the 4.0l engines I took apart, the head on all of them had some of the oil drain passeges blocked/gummed up. The block that had it the worst had ALL of the passages clogged. I would encurage you to take the valve cover off and clean these out. At highway speeds, the oil just builds up in the valve cover turning the PCV and Air Cleaner into a snorkle and the engine just sucks the oil out.

xj4play · 03-15-2005, 05:28 AM

...as promised...

Not very fancy, but functional!

Installed where the airbox used to be...

The hose from the valve cover to the can...

xj4play · 03-15-2005, 05:32 AM

Quote:

Originally Posted by ssnsltd

I did the same thing with a plastic can myself before I rebuilt the engine.

FYI on Blow-by.
On all three of the 4.0l engines I took apart, the head on all of them had some of the oil drain passeges blocked/gummed up. The block that had it the worst had ALL of the passages clogged. I would encurage you to take the valve cover off and clean these out. At highway speeds, the oil just builds up in the valve cover turning the PCV and Air Cleaner into a snorkle and the engine just sucks the oil out.

Yeah, been there, done that... passages are clean. This thing has 261K on it, so I know it needs rings. This can thing is just a temporary "diaper" until I can get a rebuild done.

thackney · 03-15-2005, 06:49 AM

Thanks for posting the pics.
I'll be doing the same here this spring.

jlayne · 03-15-2005, 08:47 AM

cool i know some guys that do the same thing, it works great... i have one of these on my jeep it is a
crank case scavaging kits this site shows it on a car, but you'll get the idea.. it creates a negative pressure in the engine and should solve the problem.. plus it blows all the goo out the exhaust.. me 2.8 blew out 2 rear mains before this.. since then.. not a drip

ssnsltd · 03-15-2005, 12:34 PM

Hmm, nice job. The gizmo I put in did not have the filter, I ran a hose back in to the air cleaner intake like on the stock system.

xj4play · 03-15-2005, 01:13 PM

Quote:

Originally Posted by ssnsltd

Hmm, nice job. The gizmo I put in did not have the filter, I ran a hose back in to the air cleaner intake like on the stock system.

Yeah, I was going to do that and still might - I just want to see how much crap this thing collects before I run a hose to the cone adapter. I did something similar with an oil bottle when I still had the stock air box on it. It caught alot of the blow-by, but still managed to screw up one end of the air filter. I don't want to mess up my K&N!

Dana44 · 03-15-2005, 01:14 PM

Hm, When i put a cone filter on my MJ (cuz its got the same engine), i had no problem with blow-by, i just stuck a little PVC filter/venter thing, and left it at that, works good

do you get a whistling noise when you take off? or driving?

xj4play · 03-15-2005, 01:18 PM

Quote:

Originally Posted by Dana44

Hm, When i put a cone filter on my MJ (cuz its got the same engine), i had no problem with blow-by, i just stuck a little PVC filter/venter thing, and left it at that, works good

do you get a whistling noise when you take off? or driving?

No, not so far...

Dana44 · 03-15-2005, 01:20 PM

Quote:

Originally Posted by xj4play

No, not so far...

hm, because my friend put a intake and filter on his jeep, and when you shift it whistles, the intake that is.

03-14-2005, 03:44 PM	#5
Dvs_Lance Registered User Join Date: Feb 2005 Location: B'ham Alabama Posts: 391 Profile Gallery Classifieds My Jeeps	I thought I had a blow-by problem and was going through air filters like crazy. Replaced the lines coming off the valve cover, and it hasn't gotten oil on a airfilter since. Just thought you might like to know __________________ 1988 red 4 door XJ 4.0, AW4 Command-Trac 3" Skyjacker Softride with AAL and Nitro Shocks 30x9.5 ProComp All-Terrains Hella H-3 100watt bulbs in factory fogs(upgraded wire) 50x4 Pioneer Head Unit and Pioneer 5.25" rear and Infinity Kappa 4" front 10" Infinity BassLink; Cobra CB 4' Firestik II (USA limited) Dana 30 front, Dana 35 rear, NP231 [SIZE=1]next mods are lockright front, SYE conversion, and BB![/SIZE]

03-14-2005, 08:37 PM	#6
ssnsltd Registered User Join Date: Jul 2003 Location: Ft Bragg, NC Posts: 52 Profile Gallery Classifieds My Jeeps	I did the same thing with a plastic can myself before I rebuilt the engine. FYI on Blow-by. On all three of the 4.0l engines I took apart, the head on all of them had some of the oil drain passeges blocked/gummed up. The block that had it the worst had ALL of the passages clogged. I would encurage you to take the valve cover off and clean these out. At highway speeds, the oil just builds up in the valve cover turning the PCV and Air Cleaner into a snorkle and the engine just sucks the oil out. __________________ '87 with 193k and '88 XJ with 153k

03-15-2005, 08:47 AM	#10
jlayne Registered User Join Date: Sep 2004 Location: milledgeville, ga Posts: 216 Profile Gallery Classifieds My Jeeps	cool i know some guys that do the same thing, it works great... i have one of these on my jeep it is a crank case scavaging kits this site shows it on a car, but you'll get the idea.. it creates a negative pressure in the engine and should solve the problem.. plus it blows all the goo out the exhaust.. me 2.8 blew out 2 rear mains before this.. since then.. not a drip __________________ 98 TJ 4 Banger, lift, tires... blah blah blah (wifes DD) 86 XJ 2.8 V6, 4 barrel carb, lift, tires... blah blah blah 61 CJ6 4 Banger, PTO winch, Stock, Rusty 00 F250 Diesel 4x4, To the trail hauler. Several others. Mostly Fords.

03-15-2005, 12:34 PM	#11
ssnsltd Registered User Join Date: Jul 2003 Location: Ft Bragg, NC Posts: 52 Profile Gallery Classifieds My Jeeps	Hmm, nice job. The gizmo I put in did not have the filter, I ran a hose back in to the air cleaner intake like on the stock system. __________________ '87 with 193k and '88 XJ with 153k

03-14-2005, 03:42 PM	#4
thackney Registered User Join Date: Feb 2005 Location: NE Ohio Posts: 101 Profile Gallery Classifieds My Jeeps	Nice write up. Can't wait to see the pictures of it.

03-15-2005, 06:49 AM	#9
thackney Registered User Join Date: Feb 2005 Location: NE Ohio Posts: 101 Profile Gallery Classifieds My Jeeps	Thanks for posting the pics. I'll be doing the same here this spring.

03-15-2005, 01:14 PM	#13
Dana44 Senior Member Join Date: Mar 2005 Posts: 748 Profile Gallery Classifieds My Jeeps	Hm, When i put a cone filter on my MJ (cuz its got the same engine), i had no problem with blow-by, i just stuck a little PVC filter/venter thing, and left it at that, works good do you get a whistling noise when you take off? or driving?