So I've been thinking about installing a breather box in my Spyder. It is currently vented only from the oil filler neck to the left carb. This isn't enough for a 2276. I get oil in that carb all the time.

The idea I had was to get a piece of 2.5 " aluminum pipe about 30" long and cap off the ends. Then welding on some mounting tabs, drilling 5 holes and welding 5 barb ends onto it. This tube would be mounted to the frame tube and it'd be out of the way, allowing me to do regular maintenance. The barb end for the oil filler neck would come out the bottom of the tube to act like a drain. All the others would come out the side. Of course the barbs would have rubber hoses going to there designated places. I was thinking about .5" hose.

A few questions to those in the know:

-Would the 2.5" x 30" pipe be enough volume? Something should be better than what's there now.

-Is a vent coming from the fuel pump cover plate necessary or even effective?

-Should I have all, but the vent going to the carb, come out the bottom of the tube?

-Should I just forget about venting to the carb and just install a small air filter in that position?

Thanks in advance.

breather

BTW, the tube in the picture is a roll of paper.

Attachments

Photos (1)
Original Post

Large stroked VW engines always seem to have breathing problems, as there's just not enough volume inside the engine case to accommodate the air in the cylinders under the pistons being pushed back and forth. If the builder doesn't open up the windows between the cylinders and notch the area between the center main bearing web and the top of the case there's just not enough area for the air to move inside the engine easily. If we can slow down this air movement, it won't carry so much oil with it.

I seem to remember being told (by someone in the know) that a breather that has 25% of the engine's displacement is enough for a street engine. A 2 1/2 x 15" tube is 1207cc's, which should be more than enough extra volume for a 2276.  Will a 3" tube fit in the space? A 3x12" tube will provide almost 1400cc's, and the bigger diameter will slow down the air movement in the tube itself. This will allow more oil to fall out of suspension faster. Also, Gordon found that 5/8" hose cured his breather woes, as the larger hose itself added enough volume so the airspeed was reduced enough for a lot of the oil to return to the engine before it ever reached the breather. I think the hose size is really important here.

A couple of stainless or copper pot scrubbers stretched out inside the tube will give more surface area for the oil that makes it to the breather tank to condense on as well. Al

Ditto the stainless steel pot scrubbers for catching the oil particles - along with a lower drain bung maybe back to the fuel block off plate/oil filler/crank case.  The line (s) to carb air cleaner induces a slight vacuum from dual carburetors to scavenge crankcase pressure which decreases internal pressure and subsequent oil leaks.

Nicely welded polished aluminum would look cool!  There are several off the shelf 356 look ones available too - but they are smaller.  First is CB Performance (EMPI has copy too).

Related imageImage result for porsche replica oil breather

Danny's breather is as Carlos describes. 2 inches diameter, I think, with baffles welded in (I don't know if he has steel wool too). It's made to look and work similar to the original 547 unit. I plan to do something like it on the car I'm building now, even though my 1914 probably doesn't need it.  

Attachments

Photos (1)

Carlos, I'll have to get some pictures up. 2" angled tube, about 18" long or maybe a little less. 1/4" drainback line to where the oil filler would be on a type3/universal case. One 1/2" fitting to each valve cover, and one to the oil filler. Two baffles welded in the upper half of the tube with 1/4" holes in them. And one 1/2" hose running to the right side carb. Mounted over the trans and angled low by the starter and high on the right near the carb.

However, I also have a line from the case running to a solenoid that triggers over 5000 rpm. This line goes to a venture in the exhaust. My thinking on this is Bug engines weren't designed to go above 5000. Or have this much displacement(mine is 2165). Extra vapors get dumped out behind you. I now have a clean engine, except for the dust........

I was wondering why that tube in Ed's picture was angled, to aid in drainage.

I've changed my design a bit. I'm going to have all of the exits, except for the carb vent exit, come out the bottom of the tube. They will all act as drains. I also had plans on welding in some baffles on the inside on either side of the carb exit.

I might stick to a 2.5" tube so that it fits up out of the way better, but I'm going to make it longer than 15". Maybe 20". I need to get a piece of tubing and see what it looks like first. Too bad I can't just tap into the frame tubing. This would also keep the inside of the frame from rusting.

I'll have to see what fittings I can find for the valve covers that will fit 5/8 hose. Does anyone know of some? They do not give dimensions on any of the sites that I've looked at so far. I have Revmaster valve covers, btw.

I'm going to weld -10AN male threaded bungs to the tube. This way the whole shebang can be easily removed if needed. All the oil fittings on my car are Fragola Performance bits and use the push on hose. I'm going to use the same to keep everything consistent looking. This might be overkill for this application, but it'll look good. That's the artist in my head getting in the way again.

Any thoughts?

@Carlos G

Your idea of using the frame tube reminded me of a guy I ran into a while back who was out four-wheeling. The guy was Marlin Czajkowski who invented the Marlin Crawler. A gear system for four-wheel drives that allows gear ratios to reach more than 1000:1 for off-roading. Anyway, he had converted the entire roll-bar setup in his off-road truck to hold pressurized air for tire inflation and combined with a small onboard compressor he could run some air tools with the system. 

I was going through some old boxes and ran across some tins that some wine bottles came in. I knew I saved them for something, so I made a breather box, or should I say tube, out of one of them.

Breather tube 1

I figured, before I went ahead and spent the money on fabricating one out of aluminum, I'd try this first. I'm only venting the oil filler and fuel pump block off plate.

The can that I used is 3.5" by 12". I also wired three pot scrubbers together a couple of inches apart from each other, and slid them in it before I sealed the lid. Since this is an experiment, I just zip tied it with some padding to the frame tube. I might also vent the valve covers, but we'll see.

Breather tube 2

I'm not a fan of the worm type clamps, but they'll do for now. I need to source some spring clamps. I'm also not a fan on how the fitting was fitted to the carb lid. Kinda janky, but that's how it came. I'll fix that later also. Hopefully this cures the oily left carb problem. Now I need to clean the engine compartment.

Attachments

Photos (2)

A 3 1/2x12" tube is huge, and will be way more than enough. What about putting all the inlets at 1 end and the outlet to the air cleaner at the other (up high on the end?) so the air has to travel through all the pot scrubbers before exiting? For that matter, it might be worth trying a breather filter on the end so you don't have to worry about intruducing oil to the carb. I would imagine the scrubbers are moving around a little with all that room- maybe add 1 or 2 more for even more surface area for the oil to condense on? I wouldn't pack them tight or anything, just enough so the bulk of the free space has material to intercept the oily mist. 

As I mentioned earlier, Gordon found that 5/8" hose cured his breather woes, as the larger hose itself added enough volume so the airspeed was reduced enough for a lot of the oil to fall out of suspension in the hose itself and return to the engine before it ever reached the breather. I think hose size is really important here. Al

PSSince you're positioning the breather horizontally, the can is a mock up and you're going to make (or have made) the actual piece, what about making it with a slightly bigger diameter at the inlet end (3 or 3 1/2", it could be more of an oval if front to back clearance is a problem) so when the thing is bolted/strapped to the tube frame oil will run down hill to the inlets? Oh- and if you vent the valve covers, only do the 1/2 side, as the 3/4 cover fills with oil at speed (the whipping of the crank doesn't let it drain as fast?) and tends to pump oil up that side breather tube instead of draining back to the sump. Most people place the breather fitting on the front top corner of the valve cover, and I've been told that a small welded piece acting as a shield so the oil can't shoot straight up the opening also helps. 

Ok, now I'm finished (I think)

Thanks for all the feedback.

The 3.5x12 inch tin is what I had. It is a little big. I have another one that is 3x13.

The pot scrubbers are wired so that they are vertical. there is one in front of the carb vent and one on either side by a couple of inches. A couple more would be better. I need to source some coarse copper wool, then I can engineer a better oil mist catcher for the end product.

I chose the drain locations for the most direct route, that still offered me enough clearance to get at the fan belt nut for turning the engine or tightening the belt. The carb vent ended up being between them and I don't know if you can tell, it angles down just a bit to clear the clam shell when it's closed. That with the interference of the Blazecut mounted on the back of the clamshell, I was limited for placement.

The fittings that I found would not support 5/8 tubing. For the end product, they will be welded on, so I'll have more choices.  After a few weeks, I'll remove it and open it up to see what's going on, and go from there. I'll also monitor the carb filter lid for oil.

These cars are ever evolving.

BTW, you'll never be finished, and we're grateful for that. Thank you.

CG

 

not a fan of running a breather hose to the air cleaner. just oils up the carb. our go to lay out is to run the bottom fitting of the breather box to the oil filler housing if using a stock filler setup or if your not running a mechanical fuel pump we run it to the fuel pump location. min size is #8 for most street motors but we also use #10 on some motors also.

When Pat D built my engine he said he only breathes the passenger side valve cover because the other side gets a lot of oil thrown at it due to the way the crank rotates. I have one hose going into the right filter. I’ve noticed no oil in the carb top or in the oil cap. Seems to work well with just two hoses

buckwheat posted:

the factory wised up in 66 by putting vents in the heads, you can do the same by doing it in the valve covers, makes a difference. bill

 

Vents in the heads? Can you expand on this, as I don't remember any vents on the heads on the 1300 (or the 1500 or 1600, for that matter).

66 and up were 1600 with the vents on the right side close to rear of sheet metal on the left side they were just north of the intake, they were hoses that ran to the vapor fill can. bill
 Bill and Jean Demeter

On Friday, February 9, 2018 8:51 AM, SpeedsterOwners.com <**************> wrote:


Reply By ALB: Breather box
| == To reply by email, write above this line. == |
|
| |
| Hello, buckwheat: We're sending you this notification because you are either following the forum, the content, or the author listed below. New Reply To Topic
| Subject: Breather box Reply By: ALB In: Spyders / Engines/Mechanical | |


buckwheat posted:the factory wised up in 66 by putting vents in the heads, you can do the same by doing it in the valve covers, makes a difference. bill 
Vents in the heads? Can you expand on this, as I don't remember any vents on the heads on the 1300 (or the 1500 or 1600, for that matter).   View This Reply
| | Unlock Premium Membership Just $49.00 Per 12 Months |

SpeedsterOwners.com - 356 Speedsters, 550 Spyders, Replicas and more https://www.speedsterowners.com To adjust your email notifications for this site, please update your notification settings. To suspend ALL email notifications from this site, click here. |

|
buckwheat posted:
66 and up were 1600 with the vents on the right side close to rear of sheet metal on the left side they were just north of the intake, they were hoses that ran to the vapor fill can. bill
 Bill and Jean Demeter

Maybe on type 3's, but type 1's have never vented the rocker cover area. And in 1966 Beetle engines were 1300's. Have you got a pic of this?

i was refering to the 912 porsche 1600. bill
 Bill and Jean Demeter

On Friday, February 9, 2018 10:31 AM, SpeedsterOwners.com <**************> wrote:


Reply By TRP: Breather box
| == To reply by email, write above this line. == |
|
| |
| Hello, buckwheat: We're sending you this notification because you are either following the forum, the content, or the author listed below. New Reply To Topic
| Subject: Breather box Reply By: TRP In: Spyders / Engines/Mechanical | |

Ive owned any number of VWs. I dont recall any of them having vented heads. The only one I never pulled the motor on was the type 3.    View This Reply
| | Unlock Premium Membership Just $49.00 Per 12 Months |

SpeedsterOwners.com - 356 Speedsters, 550 Spyders, Replicas and more https://www.speedsterowners.com To adjust your email notifications for this site, please update your notification settings. To suspend ALL email notifications from this site, click here. |

|

I've noticed this "drift" phenomenon on this site. It gets pretty bad on some threads. I guess this is what happens with a such a gregarious group, but that is one of the reasons I spend way too much time on this site. It's entertaining, but it does make it hard to search for a particular fix or how-to sometimes.

Time to crack open another beer.

it goes to the atomesphere, and its free. bill
 Bill and Jean Demeter

On Saturday, February 10, 2018 12:16 PM, SpeedsterOwners.com <**************> wrote:


Reply By DannyP: Breather box
| == To reply by email, write above this line. == |
|
| |
| Hello, buckwheat: We're sending you this notification because you are either following the forum, the content, or the author listed below. New Reply To Topic
| Subject: Breather box Reply By: DannyP In: Spyders / Engines/Mechanical | |

Yeah. So how does your breather work?   View This Reply
| | Unlock Premium Membership Just $49.00 Per 12 Months |

SpeedsterOwners.com - 356 Speedsters, 550 Spyders, Replicas and more https://www.speedsterowners.com To adjust your email notifications for this site, please update your notification settings. To suspend ALL email notifications from this site, click here. |

|

my 2 sense, I have built customer breather boxes due to space issues. but my go to breather box is the 1 quart RLR  unit. polished or black powder coated and can be ordered with push on or AN 8 or AN 10 if you go to the 3 qt unit. best money spent. all those bolt on units to the gen tower don't compare. RLR boxes have inlet for each rocker cover, and a lower one to use as a drain back to fuel pump block off or the stock oil filler housing.   I may hurt some ones feelings but those cast alum units may look cool but I never saw one that didn't leak.

one other breather set up that works is the Gene Berg units which mount to the gen tower, but they sometimes become a clearance issue with your carb linkage crossbar.

thats what i used to build in the 70s for my e production 356 race car, worked great. bill
 Bill and Jean Demeter

On Saturday, February 10, 2018 12:28 PM, SpeedsterOwners.com <**************> wrote:


Reply By Anthony: Breather box
| == To reply by email, write above this line. == |
|
| |
| Hello, buckwheat: We're sending you this notification because you are either following the forum, the content, or the author listed below. New Reply To Topic
| Subject: Breather box Reply By: Anthony In: Spyders / Engines/Mechanical | |

my 2 sense, I have built customer breather boxes due to space issues. but my go to breather box is the 1 quart RLR  unit. polished or black powder coated and can be ordered with push on or AN 8 or AN 10 if you go to the 3 qt unit. best money spent. all those bolt on units to the gen tower don't compare. RLR boxes have inlet for each rocker cover, and a lower one to use as a drain back to fuel pump block off or the stock oil filler housing.   I may hurt some ones feelings but those cast alum units may look cool but I never saw one that didn't leak.one other breather set up that works is the Gene Berg units which mount to the gen tower, but they sometimes become a clearance issue with your carb linkage crossbar.   View This Reply
| | Unlock Premium Membership Just $49.00 Per 12 Months |

SpeedsterOwners.com - 356 Speedsters, 550 Spyders, Replicas and more https://www.speedsterowners.com To adjust your email notifications for this site, please update your notification settings. To suspend ALL email notifications from this site, click here. |

|

@DannyP  I think this breather does the trick. I did notice that the tin that I used wasn't exactly sealed, so I got some weeping at the ends. I still notice some minor moisture on the carb lid that it vents to, but it's way less than it was before. My oil mist catching device in the breather wasn't ideal. These are things that will be rectified in the final. Now to find some time to do it.

MusbJim posted:

Its the way of the SOC forum! 

Exactly like sitting on the back porch BS'ing with a bunch of beer buddies. 

Carlos G posted:

I've noticed this "drift" phenomenon on this site. It gets pretty bad on some threads. I guess this is what happens with a such a gregarious group, but that is one of the reasons I spend way too much time on this site. It's entertaining, but it does make it hard to search for a particular fix or how-to sometimes.

Time to crack open another beer.

I do like beer! It is a little early, so maybe I'll have breakfast first...

Here's what I did: a $50 eBay catch can, my fuel pump block-off line and oil filler lines in one side, vented down and out to the ground. 3 SS "Chore Girls" inside the can. I eliminated the carb line all together. Keeps it much cleaner. 

 

And in in a stroke of luck, the can mounted between my roll bar tubes with 4 rubberized cable clamps just like it was planned that way. Oil breather

Add Reply

Likes (1)
JB356SR
Post Content
×
×
×
×
×