Breather tower / vented catch can

[T25Colin]

I took the pancake off the 1.9dg to sort badly perished fuel line (don’t buy Halfords e10 pipe it didn’t last 8 months) and I found the recently rebuilt carb on the recon engine (4k miles) to have a reasonable amount of oil/fuel mix around it. It got me thinking about connecting the hose from the breather tower to a vented catch can and blanking off the inlet in the pancake to stop the new engine breathing crap. Can I ask if anyone has done it? I have tried and tried to find out if the 1.9dg needs a vacuum on the engine case to draw the gases away or if it can simply vent to the air via a vented catch can. The tower appears to have no working valve inside so I guess it is just permanently venting to the intake hence the oil. Grateful for thoughts and experience? I’m also not sure at which point a working tower valve operates and have read that it is closed at idle and also another that it is open at idle. All very confusing! Also not sure if the done thing but had anyone changed the air box on the dg to a new pipe/better filter combo to get rid of a knackered air box? I’m trying to clean it all up and remove the feed of oily air to the mixture.

[Aidan]

oil vapour isn't bad for the carb or the engine generally so if the engine is running clean enough to pass emmissions then stay stock would be my advice
 

[T25Colin]

Thanks Aiden, would you recommend changing the tower to assist with venting at the right time?

[T25Colin]

Aidan… auto correct…

[hubcap61]

Fitted a catch can to my DG last year. Check it every few weeks, usually 1/4 to 1/2 full. I use my bus as a daily driver. A lot of early morning cold weather journeys. Condensation build up is caught in catch can rather than going into my nice clean Weber. Fitted mine to the right behind number plate flap. I have it vented to atmosphere just above exhaust heat shield. Cheap enough to buy and easy to fit.
Just passed MOT last week and sailed emissions test.

[T25Colin]

So have you picked up the feed from the tower and capped off the other inlet to the breather catch can so it just has the one feed and the filter on the top? Really grateful if you could share which one you fitted? Toying with any lost benefits from lack of vacuum draw in the crank case and Vs those of having nice and clean air entering the carb. Is it oil that you are seeing or a more of a mix of water, oil and fuel?

[hubcap61]

Blocked off inlet at pancake, Tower outlet to inlet of catch can, then outlet of catch can to atmosphere. Mainly water vapour condensation in catch can. Mixing with oil vapour and emulsifying.

Similar to this kit.

[T25Colin]

You are a gent. Thanks for sharing. I hadn’t seen one with anything close to the connection size of the existing pipe from the tower!

[hubcap61]

I used a short length of larger diameter silicone hose to connect supplied hose to tower. Pretty straight forward to install.

[T25Colin]

looks like a trial is going to be done next week! Out of interest are you running the stock air intake in yours?

[hubcap61]

No, I have a K&N style large cone air filter connected to a length of flexy hose . Filter is located r/h rear corner of engine bay. Had this set up for the last 3 years. No issues.

[T25Colin]

Forgot to update the thread. I took the tower off and turned it 180 degrees. Ran a pipe to the catch can and then used the exiting breather tower pipe to plumb back into the intake. The carb is much cleaner now and runs very well. I will catch about 2cm deep worth over a a couple of weeks in winter and less during long drives in the summer.

[SurfT25]

Hi T25Colin, like your set up.
Any chance you can give details of the breather?
I am interested in following your lead.
Cheers
Peter