MM951

I installed an 87 housing (including the 87+ sleeve with the 2 o-rings) and a 1 piece OPRV into my 86 block.

I recently learned this is incorrect.

What is the difference between the 86 1 piece and 87+ 1 piece? Is a different length, diameter, what?

What do I need to correct it?

86 style sleeve (w/ 1 o-ring?) and 3 piece or updated 1 piece OPRV ??

thanks

Rock

I was under the impression that the 86 OPRV was a 3 piece setup, which was more prone to failure than the later 87+ 1 piece setup.


Thats wht I thought tho

Rock

I dont really know what youre trying to say lol

MM951

what im asking is

how is the updated 86 oprv different from the 87+ oprv. Is the updated 86 1 piece OPRV shorter, longer, wider, etc then the 87+ OPRV.

Next.

The sleeve with 2 o-rings (that the OPRV slides into)

Does 2 o-ring sleeve work with any of the 86 OPRVs (3 pc or updated 1 pc)

or is the early, pressed in sleeve, needed to use an 86 OPRV?



all this seems pretty clear to me, does this make sense to anyone else??

thanks

PorscheDoc

Pressed in sleeve? All my 86 motors have the 2 orings and are removable....and you can use either the 3 pc or the 1 pc oprv in them.

Chris White

The service upgrade 86 1 piece OPRV has slightly different dimensions than the 87+ part. The blocks are machined to different depths for the valves. – Not interchangeable!!!

toddk911

Anyone have pics of it installed?

KuHL 951

What would a photo show other than a hex head attached to the oil thermostat housing? The 86 and 87 housings are the same. If you put the longer 87 OPRV in an 86 block it wouldn't fit the sleeved 86 block and would not thread down all the way even if you could get it in the block; an 86 OPRV in the unsleeved 87 block would fit but be too short and not seal; it would thread flush at the housing mount and 'look' like it was fine.

hosrom_951

Chris white: I was informed that the blocks are the same, but the oil cooler housings are different. Hence why people using say an 86 block swap with an 87+ oil cooler with the 87+ OPRV, and the 87+ block can use the 86 oil cooler with the 86 OPRV (be that 1 piece updated or 3-piece).

The updated 86 1-piece is for 86 cars only, and not interchangeable with the 87+ cars, unless the housing are swapped.

Again, i was informed this when i did the cylinder head & oil cooler in Jan 06.

KuHL 951

You were misinformed. The blocks are not the same in both depth and diameter where the OPRV mounts. You can use either housing as long as the model year OPRV style matches the model year block.

Ski

+1.

As stated (went through this building the new 86 motor for the track car that previous engine was 87)depth is different, diameter is different (Sleeve) and if you look at both parts on line, you will see the bottom seating profile is different; 86 is wider, like the bottom piston of the 86 3 pc design. Oil filter housings are the same.

Van

I'm helping a friend with an oil pressure issue... Fresh rebuild, crank bolt torqued properly, oil pressure was fluctuating, but decent, for the first few test drives. He brings it over to my house, and, as soon as he arrives, the pressure falls to zero.

It has an '86 one piece OPRV in it - but it has an auto timing belt tensioner. It also also has the balance shaft covers that have the bearing blocks integral to the cover - as opposed to the detached bearing blocks. I think it's an '87 plus engine - are there other ways to tell?

If it is an '87+ engine, would this early OPRV be a likely candidate to cause these problems?

The other possibility is a broken oil pickup tube. But he has less than 50 miles on the rebuild... and the tube looked fine when it was assembled.

Darwantae951

The OPRV isn't that hard to access, pull it and see what's really up in there.

lart951

late oprv

Van

That's what I mean guys - I pulled it, and it's an early OPRV. However, I suspect the block is a late style because of the automatic timing belt tensioner...

I guess my question is really 2-part... first: are there other ways to tell if the block is early or late? Second: do you think an early OPRV in a late block would cause that kind of fluctuating (and then loss) of oil pressure?