Help... Oil in throttle body??

[jimbobbalooba 0]

Hi all, I have been stripping down the front end in preparation of the engine removal and when I took off the air ducting from air box to the throttle body I noticed oil where it probably shouldn't be!! :confused4: (Bottom picture in blog post) http://vr6corrado.wordpress.com/2010/04 ... e-removal/

 

Although I'm doing a complete engine rebuild, I'd love to know why this is??

 

Does anyone have any ideas?

 

Thanks

Jim

[Kevin Bacon 5]

Yep that's normal for a VR6. It's oil from the crankcase breather condensing and gathering in the intake hose, which then finds it's way onto the throttle and in the intake manifold.

 

Nothing has changed over the years, all petrol engines do it. Some more than others. Even Audi RS4s do it - http://www.mrctuning.com/index.php?opti ... &Itemid=18

[jimbobbalooba 0]

Yep that's normal for a VR6. It's oil from the crankcase breather condensing and gathering in the intake hose, which then finds it's way onto the throttle and in the intake manifold.

 

Nothing has changed over the years, all petrol engines do it. Some more than others. Even Audi RS4s do it - http://www.mrctuning.com/index.php?opti ... &Itemid=18

 

Is this something I should try and combat or should I just relax a bit. I'm going to be fabricating a fair bit for a cold air intake system and could stick in a run-off valve or something; has this been done before? Possibly run a feed back up to the oil filler neck?? Is this just oil or oily water?

 

Thanks Kevhaywire you've put my mind at rest a little!!

 

Jim

[davidwort 0]

you could fit an oil catch tank but you can't vent oil vapour to the air (MOT) and the original system is probably designed 'suck' from the crankcase anyway, it's more of a problem on some engine types than others, especially at higher mileages where all that oily crud affects throttle bodies etc.

[Kevin Bacon 5]

Is this something I should try and combat or should I just relax a bit. I'm going to be fabricating a fair bit for a cold air intake system and could stick in a run-off valve or something; has this been done before? Possibly run a feed back up to the oil filler neck?? Is this just oil or oily water?

 

Thanks Kevhaywire you've put my mind at rest a little!!

 

Jim

 

I wouldn't worry about it being a sign of a worn engine or anything.

 

But no one like to see their throttle body covered in oil! The VR6 is particularly prone because of the short pipe from the rocker cover to the intake. There isn't enough distance for the oil vapours to fall out of suspension and condense on the surrounding pipes etc. VW tried to combat it with a fine mesh screen (the disc part of the breather pipe) and a clump of wire brass or copper wire shoved in the breather outlet in the rocker cover. Neither really work that great.

 

Two options though, 1 - A decent remote catch can, such as this (I have one myself and the quality is excellent) :- http://store.42draftdesigns.com/Stealth ... p_289.html

 

That will filter out the unwanted oil vapours and keep your throttle and intake clean.

 

Option 2 - Vent to atmosphere. Just run a long hose from the rocker cover down to the steering rack and let it all flood out, as it were! As David pointed out, it's not MOT friendly, but I've done it for 4 years and not been picked up on it yet, so it's up to you if you want to risk it. You will get an occasional waft of breather fumes in the car and in the winter, you'll get a nice yellowy white mayo mixture forming on the subframe / steering rack as the oil vapours condense a lot quicker in cold weather and mix with water (steam) vapours....

 

Personally I'd go with the catch can and mount it next to the radiator, and that way, the output is "uphill" and less chance of oil getting into the engine, it will just condense and run back down the hose into the tank again. I'll be doing that myself when I get round to it!

[MikLSP 0]

I was going to reply saying it's normal for some to get there via the breather but I must admit I didn't expect to see as much as you showed in that picture. I've just had mine off for a good cleaning and while there was a small amount of oil there wasn't nearly as much as that (not trying to make you worry)

I think I'd have been inclined to ask as you have if mine was like that but I found more dried on black deposit than anything else which again I believe to be normal as I've had the same with other cars.

[jimbobbalooba 0]

Is this something I should try and combat or should I just relax a bit. I'm going to be fabricating a fair bit for a cold air intake system and could stick in a run-off valve or something; has this been done before? Possibly run a feed back up to the oil filler neck?? Is this just oil or oily water?

 

Thanks Kevhaywire you've put my mind at rest a little!!

 

Jim

 

I wouldn't worry about it being a sign of a worn engine or anything.

 

But no one like to see their throttle body covered in oil! The VR6 is particularly prone because of the short pipe from the rocker cover to the intake. There isn't enough distance for the oil vapours to fall out of suspension and condense on the surrounding pipes etc. VW tried to combat it with a fine mesh screen (the disc part of the breather pipe) and a clump of wire brass or copper wire shoved in the breather outlet in the rocker cover. Neither really work that great.

 

Two options though, 1 - A decent remote catch can, such as this (I have one myself and the quality is excellent) :- http://store.42draftdesigns.com/Stealth ... p_289.html

 

That will filter out the unwanted oil vapours and keep your throttle and intake clean.

 

Option 2 - Vent to atmosphere. Just run a long hose from the rocker cover down to the steering rack and let it all flood out, as it were! As David pointed out, it's not MOT friendly, but I've done it for 4 years and not been picked up on it yet, so it's up to you if you want to risk it. You will get an occasional waft of breather fumes in the car and in the winter, you'll get a nice yellowy white mayo mixture forming on the subframe / steering rack as the oil vapours condense a lot quicker in cold weather and mix with water (steam) vapours....

 

Personally I'd go with the catch can and mount it next to the radiator, and that way, the output is "uphill" and less chance of oil getting into the engine, it will just condense and run back down the hose into the tank again. I'll be doing that myself when I get round to it!

 

Think I've seen similar on ebay and wondered what they were for... not stupid, just lazy :wink:

I'll have another look around nearer to when the engine goes back in but this definitely makes me feel better about the whole thing.

 

Thanks

Jim