14.5 OHV Crankcase Breather Tube

Ok so have a custom breather setup on my 14.5 and no longer using the plastic breather assy that bolts to end of carb. Which now I have the issue of the crankcase breather hose not having anywhere to hook to. I think the only job of the breather hose is to allow un used gasses/oil out to the carb to be burnt?
I thinking of attaching the hose to a homemade "puke tube" (like the 50's & 60's cars had) and let it run out under the frame?
Do you think this would work?

yup mike, but the carb may need adjusting. It was designed to burn that crapola that comes outta the crankcase. I'd simply stick a breather cap on it and let it be

It has been my experience that the mixture does not need adjustment when removing the PCV. The crankcase is subject to pressure changes, from the piston(s) moving up and down. The case MUST be vented to atmospheric pressure, or else seals will blow, and other bad karma. Some treehugger back when, decided that releasing those hydrocarbons straight into the atmosphere, would nearly instantly catapult us into the next ice age, and therefore decided to attempt to burn them by directing them back into the combustion chamber via the carb.

In reality, it doesn't matter WHAT you do with it, as long as it remains vented. Many (including myself) stick a cheap inline automotive fuel filter on the end to keep crap out, and pretty much call it good.

The can comes into play if you have too much oil, are running abnormally high RPM, or tend to operate on extreme angles. Back in earlier times, a crankcase vent hose was simply run stright down, and pointed at the ground.

Ok i thought so i had a snowblower and basicly just had a tube facing the base. Im just gunna run a dump tube so its not getting all over my engine.

Do whatever you need to. I do not often have problems with the PCV actually hacking up oil.

Doc Sprocket wrote:

The can comes into play if you have too much oil, are running abnormally high RPM, or tend to operate on extreme angles. Back in earlier times, a crankcase vent hose was simply run stright down, and pointed at the ground.

thats how the breather on my tecumseh is, on my bolens. it'll occasionally spit up a little, and at higher RPM's it will blow smoke out (serious blow by on the piston/rings). it just fires down onto the frame and ground

I had excess oil in one of the B&S I was working on; It was quite hilarious after running it for a bit to be enveloped in a massive smoke screen when the PCV puked oil back into the intake.

I might just make a puke tube or a catch can depending what looks better on my build lol

From what I've learned venting the PCV is a cheap little HP gainer they used to use on the old cars and what not that wont hurt the engine in any way. I also have it vented on a few of my tractors.

The other day I was reading a section in a Briggs engine manual and it had said not running the breather to the carb will shorten the lifespan of the engine. I don't know if its some bogus trying to say your better off running it through your cab or if it has been tested and shown to actually lower the lifespan. Usually the book has some interesting tips and stuff but that caught my eye.

Just thought id post it on here to see what people would think about it.

the54 wrote:

From what I've learned venting the PCV is a cheap little HP gainer they used to use on the old cars and what not that wont hurt the engine in any way. I also have it vented on a few of my tractors.

Horsepower gainer? One would have to go a long way to convince me of that. The crankcase MUST be vented, to relieve the pressure of pistons' downtravel, and relieve the vacuum of uptravel. In a 2-stroke, the engine makes use of these "side-effects". In a 4 stroke, this would cause seals to pop, dipsticks to blow out, etc.

Quote :

The other day I was reading a section in a Briggs engine manual and it had said not running the breather to the carb will shorten the lifespan of the engine. I don't know if its some bogus trying to say your better off running it through your cab or if it has been tested and shown to actually lower the lifespan.

I call total BS on this one. That's an emissions thing (running it to the carb) and what we have here, is some creative propaganda- designed to scare you into being a good little treehugger.

Like everyone else Id just run it out somewhere else just point it at the ground and maybe just maybe if I really like the engine itll get a brass diffuser plug just to keep bugs out and whathaveyou

the54 wrote:

The other day I was reading a section in a Briggs engine manual and it had said not running the breather to the carb will shorten the lifespan of the engine.

thats absolute rubbish. my 74 tecumseh runs like a friggen top other than a bit of smoke. came stock with the breather just dangling off the block pointing at the ground

yup, fartknockin rubbish

It SHOULDA read "removing this breather tube may help prevent carbon buildup on your pistons"

If you pull a slight vacuum on the crankcase, which is what routing the pcv into the intake does, it can help make power, but you'll never notice something like that on these engines.

I'm gonna have to see some kind of empirical evidence of this.

Doc, he is technically right... the vacuum helps decrease resistance of the piston on the downstroke; But so does allowing the crankcase to VENT. The HP gain is so negligible that I wouldn't even consider it worth the trouble to add a joint on the intake. It was ridiculous Propoganda, perpetrated by the manufacturers to comply with EPA regs.

Well- with THAT I will agree.Any difference WOULD be entirely negligible- to the point that you would need an INCREDIBLY sensiteive test instrument to detect the difference. Anybody claiming to feel it on the butt-dyno is full of hogwash.

I've never washed a hog. What's the deal with that?

Here's my crank case vent tube on my simplicity. I route the breathers toward the ground on most motors I mess with.

You can see that the fog of oil from various engine leaks has been cleaned off right below the carb. I still haven't added a fuel shut off valve...

Doc Sprocket wrote:

the54 wrote:

From what I've learned venting the PCV is a cheap little HP gainer they used to use on the old cars and what not that wont hurt the engine in any way. I also have it vented on a few of my tractors.

Horsepower gainer? One would have to go a long way to convince me of that. The crankcase MUST be vented, to relieve the pressure of pistons' downtravel, and relieve the vacuum of uptravel. In a 2-stroke, the engine makes use of these "side-effects". In a 4 stroke, this would cause seals to pop, dipsticks to blow out, etc.

I see what you mean and I would never plug the vent due to positive crank case pressure. Im just saying that the blow by mixing with fuel doesnt make for a fuller combustion compaired to fresh air with the vent tube disconnected.

Lol yea the engine damage thing over time does seem like a tree hugger scam!