Need Some Advice About Oil Pickup Tube

[Lawrence Coppari]

I am in the process of renewing the rod bearings on my 951. I bought the PowerHaus oil pan and oil pickup tube. Unfortunately, I did not buy the seal between the pickup tube and crank cap which the Porsche manual says to "always replace" (item 19 pp. 17 - 4). So, I have wasted a weekend. That said, I have a question about the nut that holds the tube to the crank cap. The manual shows a washer, item 17, on page 17 - 4. My engine does not have the washer. It also does not have part 21a, the O-ring.

Should I install the washer and O-ring as the picture shows? Help!

[drew1]

Lawrence,

Don't see a picture. Couldn't help anyway, just wanting to find out about putting new inserts in.


drew1

[Lawrence Coppari]

Drew1:

I followed the detailed instructions on Paragon Products' web site. They break it down into 67 steps with a typo on step 48. I asked them about this. Use the old nuts when you plastigage, not the new ones as they say.

Job is going well so far. As I said I forgot to buy the seal that goes between the oil pickup tube and block. Manual says it must be replaced. Paragon instuctions don't include pickup removal because it is not necessary to change bearings. So I can just sit around until Monday when I can get seal from dealer.

My #2 bearing was really shot. Nearly all of the babbit was gone in one corner. But crank miked out within tolerance as did plastigage check. Journal has a small taper on it, however.

I'm also installing PH boost tubes and going up on the boost to 1.1 bar. The throttle body was also reamed. Will do acceleration test wherever I get it back together and a few hundred miles on it.

[Lawrence Coppari]

Paragon's instructions say it's a 12 hour job on a 951. I have 20 in it so far and I have not gotten the pan back on. All I can say is that they are a lot faster than I am. But getting it back together will take a lot less time than getting it apart.

[Mike B]

Hi Lawrence...any hints on using plastigage...Is it a simple as it sounds or is there some special trick to it...I've never used the stuff before and will be doing the rod bearings, etc shortly...

Was your #2 bearing scored...

[Lawrence Coppari]

It was pretty easy to use. It cost 1.31 (green) at Advance Auto. You get a piece about a foot long. All you do is push the bearing into its position getting it even with the halves of the journal. The top bearing half is harder than the bottom to position but you push the pistons up pretty far into cylinder. You'll get the knack to that after fumbling about for awhile. Just lay the plastigage (looks like a piece of thread) axially across entire bearing surface on the cap. Then push the cap straight onto the bolts and tighten, torquing properly with the old nuts. Then remove nuts. Gage is squashed and probably will be stuck to the bearing. The gage came in a paper sheath with repeated markings on it. Just put the paper you cut from the sheath next to the squashed plastic and compare. It lets you know right away what the clearance is. Do one at a time. The plastigage must be carefully removed from whatever it is stuck to, either the crank or the bearing. A credit car works well on the crank - no metal objects.

I also bought some rubber hose to put over the bolts as soon as I got the bearing cap off. That way the bolts won't scratch the journal. Left them on until I pushed the piston far enough into the cylinder so that the bolts could not touch crank.

My #2 bearing had some significant wear on it. Near the end of it where the "crush" takes place, it had worn though to metal - babbit gone in two places about size of pinky fingernail. But the crank miked out to be within tolerance and the plastigage indicated clearance was ok for new bearings. This journal did not have constant gage reading, but maximum was still within tolerance. My guess is that one more year of track stuff would have caused me problems. But I don't know for sure as I am a novice at bearings. A colleague who is involved with our turbine bearing maintenance said it was a good thing I changed them.

Each bearing took me about 45 minutes to remove, mike, plastigage, and button up. The first one took well over an hour.

Number 2 was not scored, just worn. One of the others had a score mark where a piece of dirt had gotten in and left a trail.

[Mike B]

Thanks Lawrence!

[drew1]

Lawrence,

Thanks for taking the time to type all your experience. You answered one question that was bothering me. It seems that I heard that the rod bolts were stretch bolts, like the head bolts in some cars. I see they are not, but you have to replace the nuts.

drew1