crank case breathing

[rocket]

Hello all,

My 72 plus 2 has the usual crank case to air box connection and also a breather pipe at front of engine.This pipe routes straight down to road.I have recently been on a mission to cure leaks in general,only leak left is a dribble from this pipe.Whats best fix for this? Was thinking either catch bottle or route it into air box,any other ideas or opinions on best solution?

Cheers,

Ian

[Tonyw]

Ian,

If I were you I would use a catch can, the problem with routing it into the engine air stream messes up the fuel mixture and gums up everything upstream of the pipe, much simpler to use a catch can.

Tony W

[Frank Howard]

Ian,

First of all, if this is your last leak, congratulations.

I'd route the pipe back to the air box. That's what they do on modern cars to reduce emissions and that's what I did to my Europa. With all due respect to Tony, I wouldn't worry about the small amount of oil mist from the crankcase pipe having any effect on the fuel mixture. Good luck.

[stugilmour]

Ian, I am using a Moroso catch bottle with an air filter cap from the head vent. Mounted a small drain cock on the base of the bottle, so emptying should be very easy. The PO had removed the air box, so this seemed the easiest in my case. Found lots of room for the bottle in the Plus 2 nose cone, and with your vent on the front of the engine strikes me as the easiest solution.

[simonknee]

You say you have the usual connection at the back of the airbox. Is the extra breather pipe in the front of the cam cover?? The twink never came with a second second breather.

I am curious as my cam cover has a hole for such a breather but I have mine sealed up with a nut and bolt. Was there once a fashion for extra breathers? Does anybody know why this was or whether there was a particular party/dealer responsible? Miles/Ian couldn't see a need for it on mine.

You can fit a catch tank and then run it to the air intake. Or you can probably just seal it up like mine.

Simon

[Frank Howard]

Simon,

The extra breather is the one in the front of the cam cover. You are correct as there once was a time when an extra breather was in fashion, probably started by the racing community. http://www.davebean.com/ actually sells a special fitting to go into the hole that you connect a hose to. I believe the theory was that when racing the car, the high crankcase pressures would have a tendency of blowing the cam cover gasket hence the breather modification.

The previous owner installed one on my Europa routed to a plastic washer bottle. I have since routed it to a hole that is already present on all Europa Stromberg air boxes. The Elan has never had one and I have no intention of adding one either. Hope this proves helpful to you.

[billwill]

How much oil tends to accumulate in a catcher bottle anyway?

In road use how often typically would you need to empty it?

[elansprint71]

When I bought this Elan it was fitted with skinny K&N filters and the DPO had routed the breather pipe into the filter in the vicinity of cyl 4 inlet, resulting in much oily grunge in that carb choke and when the head was off that piston was clearly much dirtier than the other three.
I got some proper K&Ns with space to fit short trumpets inside and reverted to the olde skule breather set-up: rubber elbow with short length of 15mm copper tubing, vent to atmosphere.