13b Oil Return Line choice...

[Archbish]

So in putting the 13b turbo into the S3, I need to tap an oil return into the engine somewhere.  The two choices are to drill and tap the front cover, or drill and tap the sump...  There are pro\'s and cons to both - if I do the front cover, it\'s a soft metal and the oil return may be higher than the turbo (not a good thing?).  If I do the sump, it\'s a lot harder metal, but it may be lower than the oil level (apparently bad, but I\'m not sure why...  Just something I read somewhere).

[shaunwil]

Can you not just tap the sump plug bolt ? Would be an easy way to get what you want with a bango fitting to have a flush fitting.

Most of the threads I\'ve read do it from the front cover, but the alloy is supposed to be thin on the cover and some weld an alloy plug to it to tap a thread into the body.

Is the engine in one piece or can you get to the parts on their own ?

Shaun

[shaunwil]

Also the sump is a pressed steel part, you would be hard pressed having enough thread in the wall thickness to give a desired result apart from putting it in the sump plug. If you have a drill press it should be an easy job of drilling out and then starting the thread in the drill press turning the chuck by hand until a nice starting thread is made. Keeps it square to the part and then you can tap it with a standard cutter.

Make sure you get good quality taps too. The cheap junk sets off ebay are useless. Only the High speed steel ones that have ground flutes (usually in a set of 3) are any good off ebay.

Shaun

[Timmy]

You can buy a sump plug with a tapped hole in already the ones ment for an oil temp sensor, not sure if that is suitable.

[Archbish]

You can?  Surely that would hang below the car?  And according to some sites, the oil return needs to be above the oil level which this wouldn\'t be...

something like this should be ok tho??  It\'d have to go on the sump, as the front plate isn\'t flat anywhere.

[shaunwil]

Did a quick search

http://www.aaroncake.net/rx-7/naturbo13.htm

Shaun

[travellinbob]

the sump plug is waay to low for a return. That one that you linked to bish would be cool but surely you could make up the same???
 I welded one to my sump.
 cheers,michael.