Jump to content
Ultimate Subaru Message Board

Juicy (oily) idea for turbo enthusiasts


Nug
 Share

Recommended Posts

I just deleted about 500 words so I could get to the point.

 

Diesels like turbos. A lot. So they all have them (now, mostly).

 

What do diesels have that many turbo cars don't have? And pretty much no non-turbo cars?

 

Piston cooling. High efficiency turbo diesels have a jet of oil squirted onto the inside (back) of the piston to draw heat from the piston crown. If this added cooling wasn't there, the piston would get so hot, it could melt, score the liner, fry the rings, etc. Actually saw this in person with a Mack engine that had an improperly installed "piss tube". Or oil squirter thingie, whichever professional term you prefer.

 

So how do you squirt oil onto the back of a subie piston? Squirter tubes probably wouldn't work, cuz there isn't enough room for them.

 

So, my idea (which isn't new, but seemingly unmentioned on the USMB so far) is to rifle-drill the connecting rods. Keep in mind, drilled rods aren't uncommon, because many engines with floating wrist pins have this feature to lube the wrist pin.

Instead of that, picture this (exactly like a Detroit Diesel 2-stroke): the wrist pin bushing is removed from the small end of the con rod. The rod is put on a mill, and a groove is cut in the center of the bore in the rod. Now a hole is drilled into the very top of the rod. The bushing is replaced, and now an oil passage exists all the way through the rod, around the wrist pin bushing, and out the top, to the backside of the piston. A hole will be needed in the upper connecting rod bearing shell, of course. I guess if you wanted your wrist pins pressure lubed, a hole could be drilled through that, too.

 

This would be an excellent excuse to buy a high volume oil pump and an oil cooler, because both would probably be needed.

 

What are YOUR thoughts?

Link to comment
Share on other sites

If that's the case, than maybe the EA81-82 has an oil gallery handy to plumb into. But trying to get a piss tube to squirt into the right area without vibrating/breaking off and turning everything into cat food would take some fabrication skill. And a couple guniea pig shortblocks.

 

I like a good excuse to confound my machinist.

Link to comment
Share on other sites

very interesting indeed, dont see why it wouldnt work, just would need some fab work to do that to the rods, but better yet, why not come off the front of the block on the inside, and the rear of the block on the inside, and use a steel brake line, bent to a 45 degree angle to follow the wall then come out and point into the cylinder, and squirt oil into the back of the piston, you coul drill into one of three passages on the front and bring the lines down and have them tapped and screwed into the block using some locktight to hold them in. or a locking nut. using a pinching device you could crimp the end of the lines to restrict the flow, but push enough out to do the job, with out sacrificing oil pressure. i have done this to a chevy V-8 running along the bottom of the crank, modifying the oil pump to not havea relief valve.

Just some ideas to throw around.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...