Pics of my "Home Depot" oil catch can

Ok ... just finished making my oil catch can with stuff I found from Home Depot. Many thanks to Dr. Dyno for posting the instructions on his website. I used epoxy putty, which is easier to form into shapes with your fingers than JB Weld. Total cost for everything was about 5 bucks.

Here is a basic shot of it, showing the connections and the visual gauge:



Overhead view:



Detail of valve cover connection, made from 1/2" copper pipe. Notice that the part outside the can is fatter than the part inside. That's because I "sweated" (brazed with plumbing solder) a junction piece onto the end of the pipe. That gives it those nice lips for holding on the hose to the valve cover (please ignore the sloppy soldering job. I'm cleaning that up with a file.):



Upside down shot showing drain hole on bottom:



Detail of the drain nut epoxied onto the bottom:


I still haven't decided what to put inside. It will either be sponge or the "scrub brite" steel scouring pads that Dr. Dyno used. The last step will be to put on a lid and seal it up with more epoxy.

Then we'll have to see if this thing catches any oil!! My 4.0 motor has about 3 thousand miles on it, and it seems like the rings have sealed up very well. So I probably won't have a lot of blowby. But it's still good to have this there, and it's a hell of a lot of fun to build!!

hymm looks pretty interseeting.

Looks like a micro moonshine still. Neat work, let us know how it does and post some installed pics..

I'm so confused... What exactly does this thing do?

If it's to eliminate blowby, why not just re-do all the cheap plastic tubing with rubber tubing, and pulling the valve cover, and cleaning things up a bit? Pulling out the rear orifice plate, and drilling out the hole to 1/4" usually keeps the vacuum pulling things in the right direction, and eliminates the blowby issue-

Especially if you've chosen to go with a less restrictive intake setup...

I was ready to install some kind of tobacco chaw "spittle-can", until I spent some time re-doing the vac lines on my 91. THEN, I realized that the damn thing WOULD work right, but it had to be "tweaked" a little. The designers were a little anal about sizing the orifice, and probably didn't consider the coking-up it would get over the lifespan of the motor.

George2 said:

I'm so confused... What exactly does this thing do?

If it's to eliminate blowby, why not just re-do all the cheap plastic tubing with rubber tubing, and pulling the valve cover, and cleaning things up a bit? Pulling out the rear orifice plate, and drilling out the hole to 1/4" usually keeps the vacuum pulling things in the right direction, and eliminates the blowby issue-

Especially if you've chosen to go with a less restrictive intake setup...

I was ready to install some kind of tobacco chaw "spittle-can", until I spent some time re-doing the vac lines on my 91. THEN, I realized that the damn thing WOULD work right, but it had to be "tweaked" a little. The designers were a little anal about sizing the orifice, and probably didn't consider the coking-up it would get over the lifespan of the motor.

Click to expand...

Yah no doubt George2. I redid the setup on my 92 with 2000 parts and I have had no problems whatsoever. Took care of the blowby problems.

This Home Depot can thing is a joke. Why spend the time bandaiding the problem instead of fixing the actual problem?

I wonder how long the JBWeld will last?


.

waxer said:

Yah no doubt George2. I redid the setup on my 92 with 2000 parts and I have had no problems whatsoever. Took care of the blowby problems.

This Home Depot can thing is a joke. Why spend the time bandaiding the problem instead of fixing the actual problem?

Click to expand...

Did either of you read the whole post. He's got a brand new 4.0, he doesn't have blowby problems, he just wants it to catch what little oil there is.

87manche said:

Did either of you read the whole post. He's got a brand new 4.0, he doesn't have blowby problems, he just wants it to catch what little oil there is.

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You tell 'em Tonto!

not all blow-by can be stopped by replacing the vacuum lines and plastic tubes, or even by removing and cleaning the valve cover and the shield things. i have done all of that.

my 4.0 has almost 300,000 miles on it, and it blows an insane amount of oil because of piston ring slap/ wear. instead of having oil dumping into my air filter, it is dumping into an empty oil bottle. every week i add one quart and use the empty bottle to replace the full bottle that catches the blow by, i have been running like this for a while until i can rebuild/replace my motor.

-tim

Do you have pics of it installed yet?

Alright, I'll bite...

Yes, I understand it's a new motor, hence my confusion- setting it up correctly the 1st time is what this board has always been preaching and teaching me; I mean't no offense- and I really AM curious how this thing will work!

300k miles? I understand that direction too. On an older motor, some kind of device actually makes great sense, so again, I'm curious how it works.

I ran across a fishing/camping tour guide from the far-north country in Canada this past weekend that had an 87. He confessed that he abused it , but it had 270k on the ticker, and a bad real main seal leak. He just keeps pouring in fresh oil when the level drops- and he plans to do nothing more until the damn thing just up and dies- but he's been trying for years to do just that, to justify buying a new rig.

I wasn't trying to harsh- I just don't see the point of this on a new mill.

montanaman said:

I still haven't decided what to put inside. It will either be sponge or the "scrub brite" steel scouring pads that Dr. Dyno used. The last step will be to put on a lid and seal it up with more epoxy.

Click to expand...

I'm going to take the Scotch Brite scouring pads out of mine and replace them with sponge. The sponge is a better filtering medium and has more chance of trapping more oil. Then I'll reseal the lid with epoxy steel and paint the whole can red so it can look ghetto. .

Paint it yellow, and put some "radioactive" stickers on it.
That'll screw with some heads.

George2 said:

Paint it yellow, and put some "radioactive" stickers on it.
That'll screw with some heads.

Click to expand...

I thought yellow made it faster?

I would also like to see pics of it installed and a update later after you have put some miles on it. I have about 8k on my stroker and I dont have any huge blow by issues but there still is a very light coating of oil on the filter.

AARON

Here! make this into a sticker and put it on it! GREAT SCOTT!

I prefer this model:

http://forums.thevboard.com/viewtopic.php?t=60146&highlight=greddy+catch

Ok ... thanks for all the responses.

Here is some more info: I did NOT create this device to try to fix a blowby problem. The word "blowby" refers to the gasses blowing past worn piston rings or worn valve seals. The only way to truly fix blowby is to overhaul the motor. My motor is completely remanufactured and is doing great. I've also replaced the rear vacuum hoses.

One of the symptoms of blowby is increased pressure in the oil sections of the motor, which can blow out your rear oil seal. It will work its way up to the valve cover and make trouble there too. If your vacuum hose is clogged, it will blow oil into the air filter.

Here is how the CCV system works: You have a vacuum hose going from your intake manifold to the rear of the valve cover. This sucks gasses out of your motor and into your intake manifold. The hose on the front of your valve cover merely goes to the air filter box to provide a clean air intake to replace the gasses sucked out of the valve cover.

Drilling out your vacuum connection at the rear of the valve cover, and putting a fatter vacuum hose on there isn't a good idea, IMHO. This will allow more air to be sucked into your intake manifold, which is also called a vacuum leak. It was designed with a specific diameter of tubing. The nipple coming off the intake manifold has a larger inner diameter than the skinny plastic tubing. I'm going to keep that skinny tubing, because I think that is the air "bottleneck" designed by the Jeep engineers. Anything larger might create the vacuum leak.

No matter how great your motor is, there will be some oil splashing around under your valve cover, simply from the action of the pushrods and valve tappets. I think (not sure) that there is also an oil "mist" created under the valve cover from all of this action. Occasionally, a bit of that oil will get sucked into your intake manifold to be burned. That is what we don't want. Take your vacuum hose off your intake manifold, and the chances are you will see the black crud that has been getting sucked into there.

The oil catch can is supposed to catch the oil being SUCKED (not blown) out of your valve cover. You run a vacuum hose from your intake manifold to your catch can, then from the catch can to the rear of your valve cover. If there is any oil, it will collect in the can, rather than be sucked into the intake manifold, providing a cleaner fuel/air mixture to the combustion chambers.

Sorry ... I don't have any pics of it installed yet, because I'm an idiot . I put the fat inlet and thin inlets on the wrong side of the can. So ... I've got the intake manifold connection pointing to the rear valve cover, and the valve cover connection pointing to the intake manifold. I'm going to have to take it apart and do it again with a new can. Soon as it's installed, I'll post some pics.