Perry 951

Ok.. I got the parts and seals (Thanks David).. but for some reason my pressure relief valve will not fit in the bushing that rests in the block. I looked in PET, and all years show the same PN for the bushing. I am not too sure of what to do now. I hope to have the thing back in the car the weekend after next. (I will have a few extra hands) If I wait too long to order parts, it pushes that back.

So.. will the new style pressure relief valve work with the old style block and housing?? Do I need a diffrent bushing?

Bahhh.. I just want to put it together!!!

David Floyd

86 and 87 use different size pressure relief valves, my new engine is an 86 block and I had to buy a 86 valve ($250) as the one from the blown (87)engine would not fit.

Do you need my 87 valve ? make an offer

Alan C.

Daves' right. I went down the same path. A few other little know things changed between 86 and 87 like the balance shaft bearings. Surprising how many dealers don't know that one.

Alan

WillyC4S

Perry,

The oil pressure relief valve is different for the early models than the newer models. I just did mine a few months ago and it was a pain in the ***. Very tight quarters. I didn't replace the valve with the single piece item. I think the older design is more reliable since it doesn't require O-rings like the new single piece relief valve.

The 951's have a totally different heatshield and mounting system than the n/a 944's. Different bolts and removal procedure along w/ the oil hoses. I did a small write up on this a few months back (search under oil filter housing).

You'll need the alignment tool as well to ensure that the pressure relief valve doesn't get stuck due to a misaligned filter housing. Even with the alignment tool you can still misalign the housing. Just inserting the tool into the cavity doesn't ensure a good fit; you have to move the housing slightly until there is an absolutely non-binding movement as you pull out the aligment tool. After slightly tightening the bolts, use a mirror and do a visual inspection before fully torqueing the bolts down.

I also used a gasket sealer on both sides of the gasket to make sure there are no leaks whatsoever. So far no leaks.

Hope this helps.

*****

Perry 951

Ok. Time to refresh.. and pull my hair out.

This is an '86 block. I am using an '87 housing and pressure relief valve. Will the '86 1 peice valve work in the '87 housing, therfore working in the '86 bushing? I think I might be able to get my hands on one. Or... better yet.. will the '87 bushing work in the '86 block? That would be a far cheaper alternative than the highway robbery of $250!

Also.. I think I ordered a set of balance shaft bearings for an '87. I will need to check the recipts and part numbers. Of course, being an '86 block, the housings are diffrent. They spin fine, but is it advised that I pull them back out and replace with '86 bearings?

Humm.. perhaps I might not make that deadline next weekend.. figures.. I have not hit one yet. All this crap would not be an issue if UPS would have been careful with my origional block. <img src="graemlins/crying.gif" border="0" alt="[crying]" />

WillyC4S

Perry,

I'm looking at a Technical bulletin that Porsche put out (#3) and it talks about the different oil pressure relieve valves. Quite some interesting reading considering that there was a period where the first 1-piece valves didn't receive anti-corrosion treatment and there was a replacement of valves for those defective units (from July 1986 to September 1986 the valves were bad, starting in October 1986 the valves were anti-corrosion treated).

Anyways back to your issue.

The 1983-1986 cars require the use of:
1) valve 944.107.035.11
2) O-ring 944.107.935.11
3) Seal ring N 043.815.3

The 1987 (and newer, presumably) cars require:
1) valve 944.107.035.01
2) O-ring 944.107.935.01
3) Seal ring N 043.815.3

There are physical differences between the 2 1-piece valves. The 1983-1986 valve is slightly shorter, has less threads, and the shoulders are slightly different as well. The 1987+ valves have the O-ring higher up since it's slightly longer. The diameters look similar in the picture, but it's really hard to tell accurately.

The tech bulletin goes on to say that for the 1983-1986 cars, you can use the original 9215 alignment tool for this purpose (it was originally designed for the 3-piece oil pressure relief valve, it's what I used when I put mine back w/ the original 3-piece unit). It also mentions that there is a steel sleeve that is present in the oil pressure relief valve passage and must still be present w/ the newer 1-piece valve if you are retro-fitting it to those vehicles falling in the 1983-1986 model years.

For the 1987+ vehicles it recommends using a tool # 9262/1 (which apparently replaces special tool 9262). There is no mention of any steel sleeve for this model year vehicle.

The bulletin also recommends the use of the new O-rings for the oil connecting pipe of the oil filter housing. The newer version is green and is part# 999.707.043.40

My theoretical conclusion after reading the bulletin is that the your block is not compatible w/ your oil filter housing. Your 1986 block should have the steel sleeve in it and the 1987 block should not. This steel sleeve should prevent the 1987 oil pressure relief valve from fitting into your 1986 block. The oil filter housing for the 1986 is probably slightly smaller to account for the thickness of the steel sleeve, where as the 1987+ oil housing passage should be slightly larger in diameter.

If you have the 1987 valve and oil filter housing, then your valve may fit down to the point where the oil filter housing mates up to the block and then further travel is impeded by the steel sleeve of the 1986 block.

I'd get a 1986 oil filter housing and 1986 valve to go w/ it. This does not seem to be a part where newer design is better; they seem to be totally incompatible, like the automatic timing belt tensioner between 1986 and 1987+ model years.

Hope this helps.

*****

Perry 951

[quote] like the automatic timing belt tensioner between 1986 and 1987+ model years. <hr></blockquote>

Took care of that. I fitted the tensioner to the '86 block.

I suppose the only thing to do here is to get the '86 housing. Thanks for the help.. it is very much appreciated.

WillyC4S

Perry,

I didn't know you could retro-fit the tensioner to the older engine blocks.

Was it an exact fit w/o any other modifications or parts (i.e. different belt, cutout more of the rear plastic belt cover, drill additional bolt holes ... etc)? I believe the roller is different than the 1986 model as well since it has to go on the tensioner.

Thanks,

*****

Perry 951

Yea.. the covers are diffrent PN's, I had all my stuff from the '87. The bosses are there and milled to the proper height.

You need to drill and tap the holes. Of course, the holes need to be in the proper orientation. I took some measurements from my '87 block before I sent it back to Garrity. The top bolt hole (closest to the center of the block) is drilled on center. Use the tensioner assembly as a template to center punch the other holes.

Once you get the 1st bolt in and tapped, you can see that it is aligned in a way that the direction to change tension is minimal, so it would be close enough. It is something you have to play with to really unerstand.

Also, it is not a bad idea to measure the height of the outer rib on the idler gear to see if it is the same as the water pump, and also check to see if it is square with it.

Now.. back to trying to figure out the balance shaft bearings and oil cooler housing.

David Floyd

Perry951,

I am using 86 block, 86 pressure relief valve and 87 oil filter housing.

Perry 951

David.. I thought you had the '86 housing. Very cool.. all I should need to do is get the '86 relief valve then. I have an e-mail into my source. Hope he has one!!!

Now.. if Alan will see this today... I used the shafts from my '87, with the '86 housings. IIRC, the shafts are the same. I did not have a chance to check the PN's yet on the shells, but I am pretty sure that I ordered the bearings for the '87 block.

What is the diffrence in the bearings.. if any other than a number change? Last thing I want to do is fire this up and spin a bearing somewhere.

WillyC4S

Perry,

Thanks for the info regarding the tensioner conversion. Sounds like you have to have the engine out to do be able to do it correctly. Probably have to pass on that for now.

Good luck on your rebuild. Your engine looks very clean!

*****

Perry 951

[quote] Sounds like you have to have the engine out to do be able to do it correctly. <hr></blockquote>

Most definately. You need a small press or a T-Square to hold the drill straight. I had 1 stud that was off less than a degree, and it made the whole assembly stick when I tried to install it to the block. A little dremel tool took care of that, but if it was more, it would have been bad.

Thanks for the comments on the motor. It will look great when it is in the car with all the rest of the goodies.

M758

I had a similar issue on my 87 924S motor.

There are 3 Configurations

1)
Mulitpart assembly (Stock on 86 and older)


2)
Updated 1 piece assembly (Stock on later cars)

3) Here is catch
Updated 1 piece assembly for early cars. Since the block is different they require a sleeve and slighly different o-rings.

When I did my 924S I tired to use parts from #2 and it did not work. I had to used the parts from #3.

WillyC4S mentioned most of this, but I the seals are also different on retro-fit vs the new production valves.

Best thing is to go to a really good parts guy or shop or just go back to the dealer and make sure they know about the 3 type before ordering o-rings.