in article snipped-for-privacy@news.eastlink.ca, Dexter J at snipped-for-privacy@lamelamelame.org wrote on 09/03/2005 22:13:
Salutations:
>
> >> in article MYEXd.209$ snipped-for-privacy@newsfe2-gui.ntli.net, chris at snipped-for-privacy@aol.com
>> wrote on 09/03/2005 15:52:
>>
>>>
>>>> Paul Halliday wrote:
>>>>> I'm looking for an oil catch tank solution for the crankcase >>>>> ventilation
>>>>> system on my 1989 900 T8. I'm getting oil dripping down onto the fuel
>>>>> metering plate and into the airbox. I'd like to (a) stop it and (b) >>>>> get a
>>>>> handle on how much oil ... I don't seem to need to top up at all >>>>> really;
>>>>> maybe a "gloop" now and again.
>>>> ----8>>>
>>>> Paul, I've had oil drops come from the valve cover ventilation hose to >>>> the
>>>> air filter canister and clog the filter on my cars. But this was on >>>> single
>>>> carb 900 and 99 cars (had one of each).
>>>>
>>>
>>> I think nearly all of my 8v 99/900's carb or injection had some small >>> amount
>>> of oil in the airbox.
>>>
>>> suppose you could vent to atmosphere....
>>
>> Yeah ... But I'm getting oil actually on the fuel metering plate and I'm >> not
>> sure that's a "good thing" :(
>>
>> I've actually just this minute tried a VTA test. I blocked up the vac >> line
>> at the intake manifold and the end of the hose that comes from the top of
>> the crankcase. I then stuffed a breather filter into the hole and .... It
>> stalled ...
>>
>> I adjusted the throttle stop screw and it seemed to idle okay. What >> happens
>> then? Is that okay? Can anyone see any problems with that?
>>
>> Ideally, I'd like to put a catch tank inline into the system. So, idiot >> questions:
>>
>> 1. What does the vac line *actually* do? Yes, I know it sucks at idle and
>> prevents boost entering the crankcase by using a one-way valve ... But >> what
>> does it actually do?
>>
>> 2. Do I need it? Can I just stump up the basic idle and have done with >> that
>> part of the system? If so ... Do I need to do the catch tank
>> installation,
>> or is venting to atmosphere okay? I know there's a performance gain
>> associated with doing that, but I have a road car not a track car!
> Hey brother Paul - I'm afraid I don't have the answers to the particular
> questions. However I wanted to let you know that I had what I thought was
> a similar problem on an old 99 engine which turned out not to be vent oil
> at all - but simply condensing fuel varnish weeping down the manifold
> walls when it got damp enough.
>
> While the system required an annual wipe and clean when I did the filter -
> my wrench at the time said I shouldn't be bugged too deeply by it.
Yup! I'm kind of bothered, because I clean my air filter about every 3 months and the metering plate is always covered with oil. Anyway, I've been running without the PCV vac pipe today and a filter stuffed into the crankcase. Seems to run fine ... Even a little sportier!
I've got the design for my homebrew catch tank finalised, so I'll pick up the bits at the weekend and get it made. I know I shouldn't worry, but I'm a dog with a new bone and want to see this crazy idea out ... I'll probably put it back to stock in 6 months time, but it keeps me off the streets and away from hard drugs :) :) :)
Paul
1989 900 Turbo S
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