73.5 Cam tower oil hose problem

[Artfrombama]

Been through two hoses, 930 107 348 12 and 930 107 348 11.
Both are too short. Old one has no part number other than Aalflex.


930 107 348 12 pictured.

[E Sully]

Most replacement lines need a bit of work for a good fit.
With a little massaging of the bends, it will fit. Mine was the same when I first installed it.
I put it in a vise with wood to protect it and gently worked the bends till it fit. Don't do it in place with the hollow bolt, you could damage the bolt and fitting.

[ed mayo]

There is supposed to be an adapter block between the hose and case to take the larger thread oil press. switch, the banjo bolt is also longer. Those will be hard to find, just take your hose to a hose shop and have them crimp in a longer length of hose.

[Flat6pac]

I just sent you an e mail with the correct info.
Bruce

[Artfrombama]

Originally Posted by E Sully

Most replacement lines need a bit of work for a good fit.
With a little massaging of the bends, it will fit. Mine was the same when I first installed it.
I put it in a vise with wood to protect it and gently worked the bends till it fit. Don't do it in place with the hollow bolt, you could damage the bolt and fitting.

I really didn't want to flex around on the line because I was afraid of breaking the solder joint and hoping there was a part that would fit as good as the left side. I did tweak it into a good fit, installed the crush washers and tighten everything.

Originally Posted by ed mayo

There is supposed to be an adapter block between the hose and case to take the larger thread oil press. switch, the banjo bolt is also longer. Those will be hard to find, just take your hose to a hose shop and have them crimp in a longer length of hose.

I came to that conclusion after looking at later model parts diagrams, considered ordering the parts to make it all bolt together as it should. Glad I didn't.
Thanks guys.

[356RS]

I think this is what you need.

[Walt Fricke]

Art - the earlier cars had a banjo fitting to hold the oil pressure sensor, so they needed a longer hose system. When I bought a couple of the pressure sensor kits some years ago, they came with three hoses, one left side, and two rights, one longer than the other. You should be able to purchase the long hose from Porsche - look into their classic Porsche parts catalog.

Or you could convert to the newer system (don't know the exact time of that change, but 2.7s had it)which use that big block. That requires a different (longer) hollow bolt, as you would expect. Be aware that there are two flavors of this block - one with a 10mm threaded hole, which your OP sensor will fit, and one like Mark shows in his picture, with a much larger hole. For that, you either buy a different OP sender, or you buy an adapter (not a big deal).

I favor the 10mm sensor hole for this application. Your car has a 10 bar OP gauge, which requires a 10 bar sensor. Somewhere in the SC era Porsche must have thought it was bad advertising to have the gauge show less than half scale at, say, 4 bar actual pressure. So they went to the 5 bar gauge, and sender to match. Plus you can get the 10mm flavor with two posts - one for OP, and one a low oil pressure switch. That allows you to remove the stock idiot light switch and plug its hole. Unlike the idiot light switch, a plug there is never going to leak. I've not seen a pressure sender housing leak (fail, but not leak)but even if it did you'd spot and correct it well before it made a hard to clean up mess.

10mm is awfully close to 1/8" tapered IPT thread, so you have to be sure you aren't using a 1/8" ended sender - they exist, but either will leak, or will bugger threads and cause problems on the next disassembly.

[Artfrombama]

Originally Posted by Walt Fricke

Art - the earlier cars had a banjo fitting to hold the oil pressure sensor, so they needed a longer hose system. When I bought a couple of the pressure sensor kits some years ago, they came with three hoses, one left side, and two rights, one longer than the other. You should be able to purchase the long hose from Porsche - look into their classic Porsche parts catalog.

Or you could convert to the newer system (don't know the exact time of that change, but 2.7s had it)which use that big block. That requires a different (longer) hollow bolt, as you would expect. Be aware that there are two flavors of this block - one with a 10mm threaded hole, which your OP sensor will fit, and one like Mark shows in his picture, with a much larger hole. For that, you either buy a different OP sender, or you buy an adapter (not a big deal).

I favor the 10mm sensor hole for this application. Your car has a 10 bar OP gauge, which requires a 10 bar sensor. Somewhere in the SC era Porsche must have thought it was bad advertising to have the gauge show less than half scale at, say, 4 bar actual pressure. So they went to the 5 bar gauge, and sender to match. Plus you can get the 10mm flavor with two posts - one for OP, and one a low oil pressure switch. That allows you to remove the stock idiot light switch and plug its hole. Unlike the idiot light switch, a plug there is never going to leak. I've not seen a pressure sender housing leak (fail, but not leak)but even if it did you'd spot and correct it well before it made a hard to clean up mess.

10mm is awfully close to 1/8" tapered IPT thread, so you have to be sure you aren't using a 1/8" ended sender - they exist, but either will leak, or will bugger threads and cause problems on the next disassembly.

I was afraid if I used the later model block to replace the banjo fitting I might open the proverbial "can of worms" where the sender wouldn't fit or the AC brackets would interfere, not to mention spending $80. and waiting a week for delivery.

I was able to bend the steel tubing enough to bolt the thing in without stretching or twisting the hose. This threw me for a loop earlier today, was not able to find a longer hose and everyone I called had no clue. Had a similar experience when I tried to find a 73.5 fuel filter.

[E Sully]

Good to hear that you made it work.
I dealt with this back in the late '80's when my original tensioner failed and cost me a couple of bent valves. I installed the updated tensioner kit at that time.
As others have shown, from '74-89 the oil pressure mount was changed to 911 107 704 00 and 911 107 709 01. To me, in order to keep it simple, it was a lot easier to just straighten out the bends a little than replace the original fittings with the later ones. As you can see in my photo above, it worked out well.

[BoxsterGT]

I have had a request or three to "re-hose" these lines.

Once I have a fixture made up I will do these for whoever asks.

It would be $20 for the Hose and $2.50 for ea crimp. I do not charge for assembly time.

Len.Cummings at verizon.net

[Artfrombama]

Always amazed (and thankful) at the knowledge base of this forum.

Thanks guys!