Oil drip

kipa · 11 August 2009, 13:45

Not really an AS question,
but what causes oil to drip out the pipe that runs down from the filler
past the dipstick and ends near the bottom right of engine?

Bookwus · 11 August 2009, 18:18

Hiya kipa,

That tube (properly called the road draft tube) vents the crankcase. If you trace it back up you'll see that it's connected to the oil fill assembly. When the engine is operating it will generate some internal air pressure. That air pressure has to have a place to go and the road draft tube provides that outlet. In the process of of ventilating the crankcase a small amount of oil vapor is also "drafted". So, a small amount of oil does get lost in this set-up. Perfectly normal.

68autobug · 12 August 2009, 15:23

The front crankshaft pulley isn't sealed either..
it has an oil slinger which keeps most oil in the engine.
but a mist of oil can cover the engine bay
after many years...

If that hose and the one going up to the air cleaner
are blocked oil will come out the dipstick and from around the pulley...
and go everywhere....

[it did on mine.... lol ]

LEE

kipa · 13 August 2009, 03:23

I was wandering about a block of some sort somewhere.
Chers guys

Bookwus · 13 August 2009, 04:24

Hiya kipa,

A blockage of sorts would be unlikely.

As mentioned before a small amount of oil from the road draft tube is to be expected. How much are you noticing?

kipa · 13 August 2009, 21:02

it just seems to be a more since the oil change,didnt notice a drip from there before.
maybe due to thinner oil its got 15/40 in it now.
I dont think I've got a block but it good to know what one might cause.

kipa · 13 August 2009, 21:08

One other thing
I'm off to get some 12mm vacuum hosing this weekend.
is there anything I should do while the hoses are off?

Bookwus · 13 August 2009, 22:06

Hiya kipa,

Best of luck in finding that 12 mm reinforced vacuum hose. It is hard to come by. A hydraulics shop may be able to provide you with a suitable substitute.

While you have the vacuum hosing off............a couple of suggestions:

Pull off your clutch servo and check out the condition of the servo diaphragm. This is the weak spot in the vacuum system. And this would be a good time to pull the air filter on the control valve and clean it out.

68autobug · 18 August 2009, 17:17

I originally used some black hose bought from a hydraulic hose supplier
its still OK although I have bought some red Hose which is very stiff
and is rated at 300 PSI... I have found out that this is actually AIR Hose
for trucks etc.. it takes good quality hose clamps to seal it...

I have been using it for oil hose , with the different remote oil coolers
I have been using... I have had leakage problems with it..
as I haven't tightened the hose clamps up tight enough...
and they were usually in a non accessable spot...
I did happen to undo a hose clamp a few days ago,
turn it around so I could tighten it easier...

I haven't checked to see if its still leaking...
but the oil level is still fine...

LEE

kipa · 19 August 2009, 11:03

Was at the hydraulic shop today
He said to try some gates air brake hose
the specs sound ok oil, fuel and kink resistant
It is reasonable firm too.
the other piece I was eyeing up was an water/air hose designed for sand/water blasters
which was bit thicker and firmer with warp around the outside but no oil/fuel rating not really designed for automotive stuff.
Also looks like New Zealand dont have 12mm hose so I had to go with 1/2 inch,(is that what you guys used?)

volkenstein · 19 August 2009, 13:05

Kipa,
The ID of hydraulic hose varies. 1/2" brake booster hose *can* be used but clamp it really well, and I reckon it would be a job to get it to the clutch servo.
They don't stock it (the 12mm wire re-inforced) in Aus either.
I ordered from the US. BMW's uses the same hosing, but $$$'s by comparison. Ask for a price on Part No 34331115926 .
Type 2 Bay Window Kombi's use 12mm ID reinforced hose. See what a VW shop has in stock for Kombi's? Dunno the Part No.

I'll measure the OD/ID of the spare length of hydraulic hose I have.

Regards
Sean

68autobug · 19 August 2009, 16:33

Quote from: volkenstein on 19 August 2009, 13:05
Kipa,
The ID of hydraulic hose varies. 1/2" brake booster hose *can* be used but clamp it really well, and I reckon it would be a job to get it to the clutch servo.
They don't stock it (the 12mm wire re-inforced) in Aus either.
I'll measure the OD/ID of the spare length of hydraulic hose I have.
Regards
Sean

You can get all sorts of Hydraulic hose -different thicknesses... steel reinforced - single or double steel braided
they would have different pressure ratings too..
but steel reinforced hose wouldn't be able to be clamped using hose clamps...
You would need to use fittings like Earl's.. [inside threaded to bite into hose]
which are also very expensive.. these fittings are also available for hydraulic hose too..

the red AIR hose I have used comes in 12mm or 12.7mm ID.. 300PSI or higher ??

although I did use non steel reinforced hydraulic hose for the ATF pressure line
and used two good quality hose clamps which have never leaked..
hose clamps may have been NORMA brand... which i like..

so You may find some NON steel reinforced hydraulic hose which You could use hose clamps on..

and I agree with You Sean on the Red Air Hose..
its Not really flexible.. its just that the old hose wasn't long enough to go to the vacuum pipe on the new inlet manifold..
its very smooth on the inside too...
so using hydraulic hose would probably be best... even the fibre reinforced one would do the job..
I haven't seen any metric hydraulic hose about...1/4- 5/16 - 3/8 - 1/2 is common

cheers

LEE

Bookwus · 19 August 2009, 19:41

Hiya kipa,

Quote from: kipa on 19 August 2009, 11:03 ......Also looks like New Zealand dont have 12mm hose so I had to go with 1/2 inch,(is that what you guys used?)

The OEM hose was a braided wire reinforced 12 mm German product. 71 and newer Busses use the exact same hose for their brake booster vacuum. This hose is very hard to find. The only source I know of is BelMetric in Massachussets, USA. I ordered a bunch of this stuff a couple of months ago and do have it on hand, if you are interested in going that route.

Otherwise, you'll need to go with a 1/2 inch hydraulic type hose. I'd suggest that you get a hose that will be resistant to oil, gas, chemicals, etc even though the hose itself will not carry any corrosive substances. Then you'll be sure that the hose will stand up to the "climate" in the engine compartment. Basically, that's the route I went when I first got my car back on the road. And the hydraulic substitute worked fine.

Airhead · 19 August 2009, 21:13

The RH12W is exactly the same as supplied by Mercedes Benz garages its their part number 0004352182 I know because Ralph told me

Airhead

Bookwus · 19 August 2009, 23:15

Hiya Air,

Ohhhhh.................I'm gonna have to check that out.

Who's Ralph?