Can this be done (breather hose)

K-Jetronic · 04-11-2004, 04:22 AM

Hi there,

Was inspecting my engine today and found a LOT of cracks in the breather hose running from the oil tank filler neck to the back of the airfilter/air flow sensor boot. On the picture (which was taken a few years ago) it's the one running from the top middle to the left. Did some search in the archives and was hoping it could be replaced with the engine in. What do you guys think and how would you start doing this. In the archives I read it can be done but are we talking about the same breather hose? Thanks so far.

Regards,

Gerko
1978sc

PS Have got a Porsche driving academy coming Tuesday and due to easter are unable to get a replacement hose before this. Do you think this would be a problem? Engine is running fine at the moment (so I think/hope no vacuum leaks so far), for safety I have wrapped it as far as I could reach with isolation tape.

palle7688 · 04-11-2004, 06:19 AM

It can be done, just hard to get into at the back, for some it's very hard.
You need long thin arms broken in 3 places:-)
Hopefully your clamps are not rusted.
You can gain some ekstra space by lowering your engine at the back.
Raise you car and lower it onto supportstands, put your floor jack under the engine and loosen you rear engine support bolts and while checking that nothing get torn (wires and hoses and and and....) lower engine.....
It can be done.

K-Jetronic · 04-11-2004, 10:22 AM

Thanks for your reply Palle, when considering doing this without a drop do you think it's possible to do this by removing the two clamps that hold the air flow sensor boot pulling this forward with the breather hose attached, replace the hose and then put the boot back? Also would it be assumable that right now I don't have a vacuum leak if my engine is running smooth and when I remove the oil filler cap I see a drop in RPM. Or does this just mean I have enough vacuum? Would you also replace the boot while your at it?

Thanks,

Gerko
1978sc

K-Jetronic · 04-11-2004, 10:23 AM

By the way Palle from your CP I see we're in the same industry.

palle7688 · 04-11-2004, 11:26 AM

K-jetronic you have a PM.
I seems like your hose is not leaking.
Most often it's only the breatherhose that's cracking and mostly on the outside.
I've never removed the boot with engine still in so I don't know, as seen on your pic it seems like there is a second hose which you need to disconnect. If you do, take care nothing falls into cavities.
With one hand feeling the clamp the other unscrewing, it's really not that hard. And I would remove the clamp on the boot ( it has a better angle for the screwdriver) and remove hose with 90 deg. angle.
I would wait untill you have more time.

moosthuizen · moosthuizen's Garage

Gerko; I've removed the rubbercap with the hose attatched to it, after disconnecting the hose at the oil tank side. Then replaced it with a new hose. Was very simple. This way you have much more space, and it only takes 30 min or so.

The only problem encountered was the two large clamps holding the rubber boot in place (over the fuel distributor) would not allow the rubber boot to go back on, while the clamps was still on the rubber boot. What I did was to totally remove the clamps fit the rubber boot, and only then did I put the 2 clamps around the rubber boot.

Marius
'80 911 sc

tsuter · 04-16-2004, 05:12 AM

That hose is for crankcase ventilation. You don't need it back there at all. If you get it off the back of the boot, just plug that hole cut the hose much shorter and clamp it onto the large nipple on the right side of the air box just across from the oil filler spout.
If needed I can find a picture of the reroute.

tsuter · 04-16-2004, 05:15 AM

Here is the pic showing the oil breather hose reconnected to the side of the airbox instead of the back of the boot.

kqw · 04-16-2004, 05:25 AM

When you replace this hose, I am pretty sure that inside the hose on the tank side, there is a small restricter type valve. Make sure you install this in your new hose.

K-Jetronic · 04-16-2004, 10:57 AM

Thanks for the replies guys, wanna hear the good news. I was able to replace the hose without removing the rubberboot. Total time was about 10 minutes on and off. Put my left arm (with a very small wrench and a 7mm socket) behind it and was able to unscrew it!!! So seems I was lucky and first time it was really handy to be not so tall.

Regards,

Gerko Hoek
1978sc