1275 crankcase breathing

Post by **aupickup** » Sun Nov 13, 2005 1:45 pm

ok
how do you guys breath the crankcase on a 1275 ital marina engine.

Post by **Alec** » Sun Nov 13, 2005 4:13 pm

Hello aupickup,

I have made up a breather pipe (as per 1098) and bolted it to the fuel pump aperture. However, I understand that not all 1275 blocks are machined for a fuel pump. If the engine is out of the car and dismantled then it will be an easy job to drill the block there.

Alec

Post by **bmcecosse** » Sun Nov 13, 2005 5:52 pm

Just use an early rocker cover -with breather pipe - don't know why they ever did away with it. There is usually also a breather on the timing cover - this is a real nuisance on a Mini - but maybe ok on a Minor.

Post by **Pyoor_Kate** » Sun Nov 13, 2005 9:49 pm

Well, there's normally, as BMC says (shock, Kate agrees with BMC), a breather pipe on the front of the timing cover. It's a bit of a pain, in so far as it fouls the fan on the Minor; There's two solutions to this. People seem to lop the front off the chamber and put a flat front on it.

I just bent the fan blades a bit

Post by **bmcecosse** » Sun Nov 13, 2005 9:55 pm

Careful if you flatten the breather on the timing cover - all too easy to make the casing rub against the timing chain.

Post by **Cam** » Sun Nov 13, 2005 11:30 pm

bmcecosse wrote:Careful if you flatten the breather on the timing cover - all too easy to make the casing rub against the timing chain.

How? You cut into the breather and weld a flat side on it. You don't disturb the rest of the cover at all.

See:
http://potteries.mmoc.org.uk/Members_Ca ... 412_01.JPG

http://potteries.mmoc.org.uk/Members_Ca ... 412_02.JPG

http://potteries.mmoc.org.uk/Members_Ca ... 412_03.JPG

http://potteries.mmoc.org.uk/Members_Ca ... 412_04.JPG

On my Ital engine, I use the front timing cover breather and the original Minor rocker cover with the breather pipe. I also considered using the mechanical fuel pump hole (as I have a cover over mine) but I never got round to doing it.

It's been OK like that for around 4 years so far...

Post by **bmcecosse** » Mon Nov 14, 2005 10:34 am

Aye - it's ok that way - but lots of the Mini lads just take a hammer to it - and then wonder where the machine-gun like noise came from !

Post by **Matt** » Mon Nov 14, 2005 10:37 am

thats in the way on a metro engine in a mini too! we took a hammer to it! (but its not that that destoyed the fan, it was a bit of rope tied to the bonnet!)

Post by **aupickup** » Sat Jan 28, 2006 5:19 pm

hi cam

so if fitting a rocker cover with the bent outlet, do i fix a pipe onto that .
if so where do i attach it when running it past the manifold.

do you have any pics i could see please

Post by **bmcecosse** » Sat Jan 28, 2006 5:35 pm

Yes put a pipe on it - and connect it to the carb if it has the little breather connection on the side. Otherwise - I made a new hole in the air filter casing - INSIDE the inner diameter of the filter so any oily fume is drawn straight into the engine and doesn't plaster itself all over the paper filter. It works - no nasty smell and no oil leaks.

Post by **aupickup** » Sat Jan 28, 2006 7:14 pm

i have k&n air filter
i have the front breather from the timing case onto one of the pipes on the carb
it is an ital 1275

Post by **Cam** » Sat Jan 28, 2006 9:05 pm

aupickup, if you wish, you can just vent that pipe to atmosphere (I use a little k&n breather). It won't suck out the crankcase fumes and combust them but it will allow it to vent.

I can't find a decent picture of mine but basically I have a breather pipe going from the rocker cover up to near the fuel pump (on the inside edge of the battery box). It is held in place with a cable tie and has the filter in the end of it.

You can JUST see it in this piccy:

If you need a clearer picture just yell and I'll take a proper one.

Post by **aupickup** » Sat Jan 28, 2006 9:17 pm

hi cam
did this help any oil leaks???? that is my main problem
a clearer picture would be appreciated
thanks
can you send to my email please
many thanks

Post by **Cam** » Sat Jan 28, 2006 9:29 pm

Well, it did not HELP with the oil leaks but it did not cause any. To be honest if it sucks the fumes into the carb then the crankcase will be under slight neg pressure and that will help a bit with oil leaks.

I can't send attachments with the MMOC e-mail system on here so to save time here are the two pictures that I have just taken:

http://potteries.mmoc.org.uk/misc/VentHose1.jpg

http://potteries.mmoc.org.uk/misc/VentHose2.jpg

Just save them to your computer when they display.

Post by **aupickup** » Sat Jan 28, 2006 9:38 pm

THANKS CAM

the timing case breather is clear no gunge, and a pipe from there i have attached to one outlet on the carb, i think it is a hif 66, the other outlet is blocked , there is one outlet near the manifold and one outlet next to it (on the carb) not sure if that bit makes sense.

Post by **Cam** » Mon Jan 30, 2006 11:17 am

Has the carb got a square bottom or the 'normal' type jet visible and a side mounted float bowl? If it's got a square bottom and it's 1 3/4" then it will be a HIF44. If it's got a side mounted fuel bowl and it is 1 3/4" then it will be a HS6.

The three connections on the side of the carb are: Fuel inlet, Fuel overflow, and Breather inlet.

The fuel inlet should be connected to the fuel pipe from the pump (obviously!), the breather inlet should be connected to an engine breather (or blanked off if not), and the fuel overflow should be open to atmosphere (a little pipe going to the floor or something similar) it should not be blocked really.

Post by **aupickup** » Mon Jan 30, 2006 6:29 pm

sory cam yes it is a hiff44.
it has the square bottom, and on the back of the carb has 2 pipes, and of course fuel inlet.
so the one pipe nearest the manifold is the breather, then overflow.
i have the pipe nearest manifold blanked off, and the next one goes to the timing case breather.

also do i need a vented or non vented oil filler cap
au

Post by **Cam** » Tue Jan 31, 2006 12:47 am

au, the larger of the two pipes (and the highest one up) is the breather.

With your set-up and what you are hoping to do, I would say a vented cap is better, but if the rocker cover outlet is going to be vented to atmosphere then it does not make a HUGE difference. Your crankcase is not going to be under neg pressure anyway so (to my way of thinking) the more vents the better (certainly for performance engines certainly) so I'd go for the vented cap (which I have got on mine).

As a word of warning though, when I last bought a vented cap it was so poorly manufactured that the 'vent' was still blocked through the plastic injection moulding process so if I had fitted it as it was it would have been non-vented.

A quick poke with a screwdriver and a blow though it sorted it out though.

Post by **aupickup** » Wed Feb 01, 2006 7:01 pm

thanks for all the info cam.
will try it all out the weekend and let you know how i get on
thanks again
au

Post by **aupickup** » Sun Feb 05, 2006 6:17 pm

have changed it all round now, timing cover breather to the proper pipe, and fuel overflow pipe open to atmosphere.
had to richen the mixture a bit, and engine seems to run hotter .

will keep it this set up and see