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claymore 03-06-2011 09:17 AM

DIY The $10.00 Catch Can
Well here it is my latest experiment. Awhile back there was a "discussion" on catch cans and their effect on the fuel mixture arriving at the combustion chamber so I decided to build one and went looking for a proper container.

I was hoping to find one of the metallic Heineken "bottles" that were offered here awhile back but no luck in finding one now so my search continued. I cogitated that it must be capable of withstanding the heat of possible oil coming from a running engine and metal would be best. So my search continued and nothing was looking good enough until .............. Mrs. claymore came home from school one day with this....

It's an all metal mini-thermos that they use here for boiling water to make tea so it's good at withstanding high temperatures. I thought hummm this would work real nice it's metal that's good, it's CHEAP she said it cost her about $3.25 so that is good, she said they were on sale all over that's good, BUT in the photo you can see it has been dropped on it's top a couple times and it is dented, that's bad because I wanted a nice new one for my project so the search continued.

I looked all over for one I mean I went into every store in the neighborhood and couldn't find one. The closest I came was one store that said we had a bunch of them in a display last week but they are all gone now. :(

Then last week I was in another store looking for something else when whammo I spotted this baby.......

WOW it's perfect it's vivid pearl blue just like my car. So I checked the price
and it was triple in price a whopping $9.75. It must be kismet, fate, or karma whatever but I just couldn't resit a Vivid pearl blue Catch can so I bought it and brought it home to build my project.

I dug through my "good stuff" that I had saved from other projects and came up with some things to fabricate my new catch can......

What you need: This one is pretty easy all you need is a suitable container, a pair of brass hose nipples, some epoxy, a length of "universal" bracket material, some silicone, and tools including a drill with bits or the right size.

I got my hood opened and after some searching around and thinking about it I found the I could combine the mount for my "breather" oil mist separator and my new catch can together and save some fabrication. The new catch can is VERY LIGHT it feels just a bit heavier than an EMPTY coke can so the new bracket doesn't need to be very substantial.

DISCLAIMER: My enginebay has been changed substantially like removing most of the metal hard pipes, hoses and attachments for the TB water system so I probably have more room for my new catch can. So anybody else that tries this should beware that the position you end up with for your new Catch can may be a little different than mine.

The basic reason I picked this spot was it was close to the original hoses for the stock system and trying to bring this in the cheapest I could I found in this position I could get away with using the stock hoses.

So onto the modifications needed to turn a mini-thermos into a catch can.

One word of caution...... the length of the inside of the can is shorter than the average drill bit so remember not to drill an "Extra" hole across from the new hole you will be adding. Here is an old trick to prevent any unwanted holes.

Just wrap a length of tape (any tape will work) around your drill bit at the depth you want and unless your really force it the tape stops the drill from penetrating too deeply.

All you have to do is drill a hole that JUST lets the brass hose nipples slip into it as small as you can keep it so there is less to seal later. The can itself is VERY THIN metal and drills very easy so go slow and don't dent your new catch can by using too much force.

I got the holes drilled on different levels and not inline with each other so the incoming air would not go directly back into the exhaust port but would have to travel a bit so any suspended oil would have more time to separate and fall to the bottom.

I slipped the nipples into the new holes and decided to even shorten the exhaust one a bit to move the ends further apart and added a short length of old hose to make the separation as large as possible.

Once the new holes were drilled and everything cogitated on and looking good I sealed the inside of the new holes with some silicone sealer to make a new vacuum seal inside the inside layer of the two walls of the catch can.

Mine is even better than Mrs. claymore's as mine has a plastic coating inside.

You can see the silicone sealer and extra hose section.

I finished my location survey and figured out where it was going to go so it was time to mount it. Since it is so lightweight and the bracket is just supporting it I decided to use epoxy and got my parts lined up and mixed up a batch and poured it on.

This epoxy is great if you know what you are doing as it dries solid in about 5 minutes so you can move the part around without the epoxy "flowing" more as it dries. This way you can move onto other things while the epoxy dries.

I didn't remember to get any photos but I made "Dams" out of masking tape to seal the outside of the cans and make sure the nipples stay where they should be.

All I did was slip a piece of hose onto the nipple after putting some saliva on the OUTSIDE of the hose and a bit of silicone on the inside so it would slip off the nipple easier.

Then I just ran some lengths of masking tape around the hose making sure to really seal the bottom edges to prevent any epoxy from leaking out.

Once I had the hose circled in tape with the bottom sealed to the can real well I simply wiggled the hose carefully and pulled it out of the tape so all there was left was a circle of tape sealed to the can but with a space around the nipple.

Using a pair mini-scissors I carefully cut the top of the masking tape so my dam was about a 1/2 inch high and I had plenty of room to pour in the epoxy.

The epoxy was left to dry in the first dam on the first nipple and then I did the same on the other.

A day later I trimmed the epoxy a bit with my trusty dremel tool to smooth it out and ended up with this. (The Pepper can is just for size comparison).

And I used an "old time" method of checking to see if it "held" a vacuum. With the lid on and closed tightly I covered the hole in one nipple with my finger then I sucked on the other one and sealed it with my TONGUE. This method was even in some old factory repair manuals for checking the vacuum advance canisters on distributors and interestingly enough most humans can pull -1.5 HG vacuum with their mouths. :eek:

This is where I found out that the color of this was EXACTLY THE SAME AS VIVID BLUE PEARL stock Fit/Jazz color :p

The epoxy comes out black so I got out some of my VPB touch up paint and tried it on the bottom of the can where it wouldn't show and sure enough IT WAS AN EXACT MATCH. The blue paint around the new nipples is Honda Jazz VBP touch up paint and you can tell from the photos it looks just like the can color.

So after a nice layer of wax to protect the paint it was time to mount it. A quick shot of flat black was sprayed on the mounting bracket I had fabricated earlier. Here it shows how the "Breather" separator mounts right to the same bracket and uses a thumb nut for easier removal.

As you can see the bottom of the breather can sits on a hard line and helps support the weight of them both.

Yea yea but what does the new catch can look like mounted.........

I could have used both stock hoses but the one in front used to come out right between the insulated silver hose and the black hard coolant pipe but it didn't look "perfect' so I dug out some hose left over from other projects.

I re-routed the original hose to this new location and just cut a length of new hose just maybe an inch longer than the stock hose and this way it looks "cleaner" to me.

I also didn't fit any hose clamps to the connections at the catch can as the new nipples are longer than stock and it's a vacuum situation anyway so the pipe will be sucked tighter not blown off and it looks better.

with this mounting I can remove the cap to check for any oil caught and to remove it for emptying there is just one nut to take off. I would have used a wingnut to make it even easier maintenance but for some reason nobody sells wingnuts here. I have looked high and low but not one hardware store has them here........ nuts................. :p

OK time for the new engine bay shot........

So there it is the $10.00 catch can.. could you do it for $10.00? Probably if you have some epoxy, and silicone sealer hanging around. The can was $9.75 and the nipples are about 50 cents a piece so you may go over a bit but it's still LOADS cheaper than a $100.00 catch can.

So the experiment begins will it catch any oil or not... we shall see but even it it doesn't it was cheap. :p

claymore 03-09-2011 11:15 PM

Well took a little trip today 20 minutes one way and back another 20 minutes at around town speeds of 25-30 mph with a bit of time at higher speeds of 45-50 mph. This is the first time I have driven with the new catch can and guess what IT WORKS GOOD.

Got home and took the lid off and presto changeo a drop of LIQUID OIL on the bottom and mist tracks on the sides from the OIL & AIR mixture hitting the side of the catch can.

As you can see with your own eyes the tracks are from when I had it turned upside down there is enough REAL LIQUID OIL to run when turned upside down.

Now imagine if it caught this much driving at slow speeds for 40 minutes how much is it going to catch on a nice long trip or over the course of a month or so. Stay tuned for updates.

claymore 03-13-2011 07:14 AM

Found one more benefit of a catch can that should make our tree loving members happy. The Twin loop muffler I have has a large maybe 3 inch outlet and as a normal part of my car washing I use my special wheel and wheel well sponge and I wash out the end of the muffler and usually there is some residue on the sponge.

It's not too much you can't really see it but there used to be enough that you could see it on the sponge. Today got a nice surprise the sponge came out CLEAN no residue that I could see.

So it looks like separating the oil from the air being passed back onto the engine to be re-burnt helps clean the air too. The heaver petroleum distillates like engine lubricating oil don't burn as quickly so there is more residue that doesn't get burned in the combustion chamber. That residue gets passed out the tailpipe which a catch can prevents.

Just remember to dispose of the oil collected in the catch can in an environmentally safe way.

claymore 03-19-2011 12:19 AM

Finally got to take a nice "hot run" on the local expressway at very high speeds today. There is a correlation to how much liquid oil is separated out of the oil/air mixture coming out of the PCV system when the engine speed is considered.

Today while traveling at high engine speed for about 45 minutes starting with an empty, clean catch can and when checked after the trip there was about 6-7 drops of oil in the catch can about the same size as the drop in the photo in post #2.

Looks like it's doing it's job pretty good. :p

claymore 03-21-2011 01:42 AM

Got to go on another high speed run and you can see from this photo just how it's working.

If you look closely at the wall of the can you can see how the oil and air come in the black hose then the oil sticks to and runs down the wall of the catch can to be collected in the bottom just as I predicted. :p

This amount of liquid oil is two days of high speed driving maybe an two hours total with some surface street speeds in there also. Note the oil residue on the end of the hose and the LACK of residue in the brass outlet this is working great. That oil without a catch can would have been injected into the intake manifold and into the combustion chamber lowering the denotation point for your engine.

If you look REAL close at the largest oil blob you can also see some small black pieces of debris I THINK it must have come from inside the section of hose that I used as it had been hanging around in my "good stuff" for maybe two years and possibly some dust got in there. Will keep an eye on it to see if more shows up as the can was clean when it was installed.

You can also see the new upper bracket I fabricated out of some more universal bracket, and an old aluminum coat hanger wrapped around and cut off after making loops for bolts. Then it was painted VPB with my trusty old touch up paint. After I thought about it and watched it with the engine running I deduced that another bracket on the top section would be a better way to hold it more securely.

You also should be able to see that THIS is the correct installation procedure connected into the PCV SYSTEM not the breather system as some people on the other forum are recommending. :rolleyes:

macbuddy 03-21-2011 03:20 PM

Hey claymore, according to the freaky site, this catch can will not work without using a piece of screen material to condense the vapors into liquid. Therefore, the "imaginary" oil at the bottom your can does not exist! :)

EXWRX 03-21-2011 04:13 PM

It's all photoshopped!!! :p

claymore 03-21-2011 10:08 PM

Yea their so-called "experts" sure need to bone up on their physics lessons. It's really very simple there is no reason to "Condense" anything because of that old buddy GRAVITY. The oil is heavier than the air so just moving across a gap it falls out of suspension toward the center of the earth just by gravity as gravity has a stronger pull on things that are more dense (heavier).

Maybe he thought that up to use on his "3 speed powerglide".

And he is the same one that talks about the fuel air mixture and how the heavier fuel gets separated inside the intake manifold and the lighter air moves on while the heavy fuel sticks to the intake manifold walls. Copied and pasted I think or he would understand that the same thing is happening here.

Disclaimer: I have to say I DID use squashed metal wire on my breather system capture can BUT in this case there is no lid and the exhausted air/possibly oil mixture is open to the atmosphere so there is no vacuum to direct the flow of the exhausted gasses.

In this case the squashed wire is used to trap any oil and prevent it from splashing out of the container not for separation which uses gravity again even in the absence of any vacuum. But I'm pleased to note there has been only a MINUTE film of oil collected on the squashed wire and absoulety NO LIQUID OIL, NONE WHAT SO EVER collected in the 3 YEARS that is has been installed on my car.

I have never found anything collected just proving my point that installing one into the breather system is a complete waste of money.

If you are boosted and or have an old engine with a lot of miles and you are collecting any substantial amount of liquid oil in a separator installed into the breather system that means one thing .................. YOUR RINGS ARE NOT DOING THEIR JOB OF SEALING THE COMBUSTION CHAMBER FROM THE CRANKCASE and you have larger "issues" to worry about than capturing the blown out oil from your failing engine.

claymore 04-11-2011 12:11 AM

Well it's been a little over a month and now I have a drop the size of a quarter about 1/8 inch deep collected in the bottom. The oil doesn't flatten out like water on the coating inside the can it beads up like water on a fresh wax job and collects in one blob of oil. Will make clean up very easy with a paper towel.

It's working great to catch that much oil as it's been a month but I only drive it like every three days or so.

claymore 04-20-2011 01:01 AM

Today after a nice little high speed run on the expressway figured I would clean out the collected oil. Ended up with about a half dollar sized blob about 1/8 inch deep.

Just rolled up a paper towel and stuffed it down to the bottom waited 10-15 seconds and pulled it out and nice and clean. The plastic coating on the inside of the catch can works great the oil doesn't stick to it so the paper towel just sucked it up.

Of course for all you tree huggers I collected the paper towel with the oil and put it into a ziplock bag to be saved until hazardous waste day rolls around.:rolleyes:

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