BMC breathe

[ditchy]

Hello everyone.

I was just nipping a fuel line that I suspected was leaking a little...Job done. Then a curious look around the engine as u do admiring the minor oil leaks when this caught my eye. On the top of the rocker cover where there's a breather pipe, there's some sort of bolt blocking the pipe and tied away neatly. Im not having engine trouble at the minute but was wondering if you guys on here had any advice on a filter to attach or weather I should just leave it alone and move onto other jobs. Here's a picture. Thanks in advance.

I can't work how to add photo, but I don't think there's much more to explain.

[bizzard]

Hello everyone.

I was just nipping a fuel line that I suspected was leaking a little...Job done. Then a curious look around the engine as u do admiring the minor oil leaks when this caught my eye. On the top of the rocker cover where there's a breather pipe, there's some sort of bolt blocking the pipe and tied away neatly. Im not having engine trouble at the minute but was wondering if you guys on here had any advice on a filter to attach or weather I should just leave it alone and move onto other jobs. Here's a picture. Thanks in advance.

I can't work how to add photo, but I don't think there's much more to explain.

Assuming this is a 1.5 or 1.8 engine, yes that pipe should go into an air filter unit to ingest the fumes. However there should be another crankcase breather on one of the engines camshaft cover side plates which are very very prone to gunging up and blocking, Yours must be ok at the moment or pressure would have built up and blown oil and fumes out from various places like oil filer cap, dipstick tube, crankshaft main seals ect.

[ditchy]

Thanks alot bizzard for the fast reply. Yes mines a 1.5 engine. So do you think one of those universal filter will surfice? I cant belive that I've not noticed this before. Sometime you just have tunnel vision on engine components until the point you have a problem and then you start looking. Also i take it that it wouldnt hurt to locate this cranck case filter and give it a good clean too. (what does it look like?)

[bizzard]

Thanks alot bizzard for the fast reply. Yes mines a 1.5 engine. So do you think one of those universal filter will surfice? I cant belive that I've not noticed this before. Sometime you just have tunnel vision on engine components until the point you have a problem and then you start looking. Also i take it that it wouldnt hurt to locate this cranck case filter and give it a good clean too. (what does it look like?)

Yes probably extend that breather tube a bit more and tie it up higher than the engine. It doesn't necessarily need a filter on it but some kind of a little hat to stop dirt getting in or even a bit of say nylon stocking tied over the end would keep dirt out and allow it to breath.

Yes I'd remove that side plate and give it a good clean out.

[ditchy]

Thanks for the advice! I'll fit that job in this week.

[Darren72]

Wheres this exactly on the 1.5?

[Tony Brooks]

Where's what?

 

The original post seems to indicate that he has a breather hose on the rocker cover as per many BMC vehicles..

 

There is usually other breather connection on one of the two side cover that are located below the manifolds. It is often the front one but could be the back one.

[ditchy]

The one that I was refering to is on the top of the rocker cover. Only a short hose with what looks like a massive bolt head blocking it. Ive not had a chance to investigate or change things there as yet.

Edited March 27, 2014 by ditchy

[Tony Brooks]

That's typical for vehicles - from which very many marine BMCs were sourced - but the official Newage/Tempest ones did not have a breather on the rocker cover.

 

Some Calcutt engines used a "Ford" type oil filler cap with a mesh inside it that acted as a breather and I think the plastic BMC version would also fit. These would give a high level breather with oil mist separation.

 

My personal view is that as BMCs seem to develop a fair bit of crankcase pressure it would do no harm to fit a longer hose and run it down into an old pop bottle beside the engine but it really should not be necessary. Especially if you do as advised and make sure the oil separator on the breather on the side cover is nice and clear. If by some chance you do not have that side mounted breather then please do unblock the top breather and use that.

[ditchy]

Thanks for the advise...Theres not enough proactivity these days.

[Speedwell]

Shouldn't the rocker box breather be fed back to the inlet manifold or is this only the 1.8 ?

Edited March 31, 2014 by Speedwell

[RLWP]

Shouldn't the rocker box breather be fed back to the inlet manifold or is this only the 1.8 ?

 

And the answer is... it depends

 

If the engine has a crankcase breather pointing into the bilge, and it has somewhere along the line acquired a rocker cover with a breather from a vehicle - what would be the benefit?

 

And there are other arrangements - Tawny has a breather on the oil filler connected to the filter housing

 

Richard

[ditchy]

Turns out one of the side cover that is below the manifold is being fed to the side of the air filter. Now the one on top of the rocker cover that was the one in question, what shall i do with it? Hold it high and stop crap getting in with top hat, gause etc or extend it and send it to the bilge to collect in a bottle? (or leave it blocked off?)

Im probably making more fuss about this than needed. Thanks for the feedback nevertheless.

[bizzard]

Turns out one of the side cover that is below the manifold is being fed to the side of the air filter. Now the one on top of the rocker cover that was the one in question, what shall i do with it? Hold it high and stop crap getting in with top hat, gause etc or extend it and send it to the bilge to collect in a bottle? (or leave it blocked off?)

Im probably making more fuss about this than needed. Thanks for the feedback nevertheless.

Hoping you've removed that side plate to clean the baffle and passage way at the back of it. The breather tube on the valve cover could either be extended up higher than the engines top and protected with a hat or filter or looped down into a bottle.

[Tony Brooks]

or even blocked off as long as the side cover one is clean and free of crud. I would lead it down into a bottle.