Mike65

Have you got the blacktop Zetec? If so the PCV is at the back of the block (assuming you have it on a rear wheel drive car and not sideways) on the right side. Look down below the headers at the rear side of the block and you'll see a pipe coming out of the PCV which is simply pushed into a rubber grommet - you can just pull it out. Unless the valve is being operated by a vacuum source, which your setup isn't doing, then you risk the same problem I had,

I've had a good chance to get my head round this now. When I fitted the 45s I lost the vacuum to the PCV that was originally on the downdraught Weber. I did the old school trick of running a hose from the PCV and hang it under the car. I had no outlet at the top as the Retro Ford BDA cover for the Zetec is on the left side and very close to the twin Weber linkage. So I blocked it off thinking the PCV would be enough. Big mistake. The PCV doesn't operate with positive pressure in the crankcase, only with a vacuum lift from a source (such as the inlet manifold). I tapped into the inlet manifold to do this but it played hell with the carbs so I blocked that off too. 6 months down the line and the engine was pissing oil out of every gasket and seal. I now know (from useful info above) that taking out the valve in the PCV AND opening the valve cover outlet and running both into a breather catch can has solved the whole issue. It's not sufficient for modern emission engines but fine for our old stuff. I was worried I had blown out a gasket or crank seal but the engine is now oil tight and dry again. So is my garage floor!

I ran mine for over a year with no breather but it gradually started pushing oil out of the engine gaskets, crank seal etc. cos the internal pressure was too high. The ebay item no. is 12184093998 and cost £35 from 'aclubuk'.

Finally finished the job, fitted a breather catch-can (£35 off ebay). One hose in from the valve cover, one from the empty PCV. Given the car a fast blast for 1/2 hour and absolutely no oil blow. Result. One tip: I wanted to route the hose round behind the engine and needed to get some 'bends' into it. I cut 2 lengths of a wire coat hanger and shoved it into the hose, then it could be bent into any shape and the bends stay there. Don't know if it's a first, but it works great.

So following the good advice above, I 'gutted the PCV' on the basis that it was not connected to a vacuum source and therefore permanently closed. This was certainly causing too much crankcase pressure which was causing the oil to pump out of the only opening, my valve cover outlet. See the pics how I got the valve out of the PCV. Put the empty PCV back in, blasted the car out on the A23 for 5 miles and Bingo - no oil pumped out anywhere. Just waiting for the oil catch-can breather to arrive so I can put the valve outlet pipe into something a bit more proper than a Coke can. Thanks for advice guys. Pic 1, cutting off the bottom of the PCV with a hacksaw. Pic 2, the valve and spring out. Pic 3, just a quick file and pop the empty PCV back in.

Thanks guys. I'm using that Retro Ford BDA cover, it's expensive but fab. Its got a baffle inside but I reckon Katana is right, all the time I got the PCV in, I got too much pressure in the crankcase. I've ordered a neat 1/2L breather catch can and will hook it up next week. This weekend I'll remove the PCV and see if I get less oil blowing out the valve cover. Got the pipe stuck in a Coke can for now. Let y'all know.

Thanks for the reply Katana. When you say gut the pcv, I guess you mean stop it operating as a valve, just as an outlet from the crankcase. ? I'm going to run one hose from the pcv outlet and one from the valve cover, both into a vented catch can. Judging by the amount of oil that blew out of the valve cover when I revved the engine hard, looks like I'll be emptying the catch can often (?).

I've had a blacktop 2 litre in my Mk1 Cortina for a few years. Went over to twin 45's last year but need some advice on a breather set-up. I've obviously got too much pressure as the gaskets have started leaking. Currently only got a PCV but no breathing from the cam covers. Recently drilled an outlet into the cam cover but it blows out way too much oil and don't know where to send it. Don't want to tap into the inlet manifold as I think it will upset the carbs. Any advice would be appreciated guys.