Crank breather blockage?

[mrmorrisminor]

Hi all,
Having a bit of trouble with excessive oil leakage from the rear laberynth seal on my standard 1098. I have started by investigating the crank breather as excessive build up of pressure would blow the oil out (am I right?) Anyhow on my other minors the breathing has been from the top of the rocker box however on this one this is not the case...... there is a strange affair coming out of one of the side cover plates (access to the cam followers). It is a large 90deg elbow with a cylinder about the size of a loo roll and onto this the breather pipe is connected to the air filter. (I've found a pic from the internet to show the part I'm talking about, mine does not have the rocker breather....yet!)

I have blown down this and it appears to be blocked as it is VERY difficult to blow through. My question is, what is inside this cylindrical housing, is it some type of gauze? And what would be the best way to clear it?

I'm thinking of putting my spare rocker cover on (with breather) and changing the side cover plate with a standard one if it is going to be too difficult to clean out......


Any suggestions or knowledge gratefully received [frame][/frame]

[brucek]

You have the last type of breather arrangement and the cylinder is the same as the type used on the 1275 midget engine except on the 1275 the breather is on the timing cover as there is no tappet chest for it to fit to. Inside is a gauze material a- a bit like a pan scourer - but it is very difficult to remove it to get it clean. I know some folks have carefully cut the breather open and removed the gauze that way but it's a lot of work. I think the gauze sits on a little rib inside which also makes it difficult to pull out or put back. If it's blocked (and it does filter out a lot of crud) try soaking in petrol overnight and then , if you can, blow an air line through it. A toothbrush will clean as far as it can , especially those with the flexible necks. I cleaned my 1275 breather this way but have no real idea if it is as completely clean as it should be as the engine isn't back in the car yet. Good luck

[mrmorrisminor]

aha! good thoughts.... well I have spares of the earlier type (rocker cover) so have a plan B. it was a recon engine about 20k miles ago, it has always leaked a bit out the back but has got worse recently.... it made a right mess at Brooklands on Sun, but guess a blocked breather is a good place to start.... don't really want to be pulling too much apart!!

[brucek]

Just having a look at that photo again - and it looks to me that this car is set up to breathe via the tappet chest AND via the rocker cover. The late 1000's had the breather arrangement via the tappet chest and using the cylindrical breather as previously described. It also used a plain, no vents, rocker cover. Early 1000's used a vented rocker cover that fed to the air filter. It seems that this car has both systems. If yours is set up like this one is then that might explain your problem.

[mrmorrisminor]

No, mine just has the elbow out the side of the crank case (which is blocked)..... and an un-vented rocker cover. So my guess is it's getting a little 'pressurised' to say the least.

I'll try the petrol and if that does not work I'll revert it to the earlier set up like my other minor

[bmcecosse]

Wash it with petrol etc - if still blocked - one 'cure' is to set it on fire........ But beware how much petrol is inside first........