expanding oil return tubes

[turbo ride]

Guys-
I foresee the replacement of both passenger side oil return tubes on my car ('91 964 Turbo). I've been searching and what I'm most dreading is the in situ expanding of the tubes. They sound like a real PITA.

First - I'm planning on using genuine Porsche parts.

Just curious what kind of advice and BTDT you guys can offer regarding methods you've used to get them expanded/installed. And any lubrication on the seals...

Thanks!

Ohh and since you guys like pics - here's a pic of my car taken right after I got back from a 820 mile drive - all 2 lane mountain twisties. Tons of bugs - but they're hard to see. And (I'm told) a 1 of 10 Japanese market only 964 Flachbau I saw at a shop. Next to it was a 964 3.8 RS...

[turbo ride]

Ok first they posted upside down and stuff and couldn't figure out how to change so I just deleted them - here they are:

[Spenny_b]

Originally Posted by turbo ride

Guys-
I foresee the replacement of both passenger side oil return tubes on my car ('91 964 Turbo). I've been searching and what I'm most dreading is the in situ expanding of the tubes. They sound like a real PITA.

First - I'm planning on using genuine Porsche parts.

Just curious what kind of advice and BTDT you guys can offer regarding methods you've used to get them expanded/installed. And any lubrication on the seals...

Thanks!

Ohh and since you guys like pics - here's a pic of my car taken right after I go tback from a 820 drive - all 2 lane mountain twisties. Tons of bugs - but they're hard to see. And (I'm told) a 1 of 10 Japanese market only 964 Flachbau I saw at a shop. Next to it was a 964 3.8 RS...

Hi, nice motors!

Can't help with the expanding oil return tubes, I fitted new single piece items as part of my rebuild, but I did use silicone grease (equivalent to the Dow Corning stuff often referred to on here and in the Engine Rebuilding forum). A small smear on the o-rings and they pop in with a little persuasion, not hard at all. Not sure what the issues are with the expanding ones; iirc, my engine had a couple of expanding joints before I pulled it for rebuilding; am pretty sure they never leaked. Have a search around, there may be some upgraded collapsible tubes available from some of the well known rebuild shops (or even here in the Pelican store)

[kenikh]

I've never had issues with collapsible tubes. Bottom line: if they start to leak, get new ones. You can also JB Weld the seam (tube body, NOT to the head) to ensure a leak free fit.

[Spenny_b]

OP, there's another thread on the same page discussing -->

http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/826714-oil-return-tubes.html

[turbo ride]

Originally Posted by Spenny_b

OP, there's another thread on the same page discussing -->

http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/826714-oil-return-tubes.html

Yes somehow I missed that....
But it's a totally different question.

[markivtruck]

the best grease to use on the o-rings is dielectric the same grease you put on spark plug ends and be liberal with it. coat inside of tube and open and collapse it several times before you install it. also coat engine and cam housing with grease. sometimes you have to remove heater box where oil line connects to engine. that is the worst one. be patient and work slow. good luck!

[turbo ride]

Interesting. Curious - why dielectric grease? Never heard that before but I'm curious!

Thanks-

[kenikh]

^ It is clear, has nice viscosity and will hold back oil.

[JFairman]

Before installing my collapsible oil return tubes with o-rings I tried vasaline, wheel bearing grease, redline assembly lube, and motor oil on them and then expanded them in and out so I could feel which lubricant made them slide easiest.
Vasaline was the worst, wheel bearing grease was pretty good, and I settled on 20w-50 motor oil because it worked good for 2 slides in and out before it got harder to slide them and I was only going to expand them once.
It's not easy to get a good grip on them with two hands while under the car to do it.
I used motor oil on the o-rings on the ends that slide into the case and cam towers.
I never tried dielectric, lithium, or silicone grease. Whatever works.

They should be installed so the bigger diameter tube is toward the case so oil doesn't pool up against the thinner tubes o-ring inside the tube if they are installed the other way.

[unclebilly]

WHOA! NEVER use silicon grease with silicon o-rings! This includes Dow Corning 111.

I have used the expanders with good success on a race engine. They are tricky to install but can be done. I think I just used motor oil or lubriplate to lube them up.

[JFairman]

Originally Posted by unclebilly

WHOA! NEVER use silicon grease with silicon o-rings! This includes Dow Corning 111.

Why is that? I have a little jar of silicone divers grease that scuba divers use on their equipment, would it do something bad to a silicone o-ring?
The o-rings on the oil return tubes are not silicone, they're green viton.

FWIW, there is a silicone o-ring between the oil pump and engine block in the old single cam 4 cylinder and 6 cylinder BMW engines. It looks and feels like silicone anyway, and it will swell up like silicone does if you soak it in gasoline. Then it'll shrink back down to regular size when it dries out.

[911nut]

Originally Posted by JFairman

Why is that?
The o-rings on the oil return tubes are not silicone, they're green viton.

+1
I've used the Dow lube on two expandable return tube installations with no issues.

Brandon, here's the technique for installing the return tubes: http://forums.pelicanparts.com/porsche-911-technical-forum/800276-came-up-good-technique-expanding-oil-return-tubes.html