2000 Boxster S oil leak - 986 Forum - The Community for Porsche Boxster & Cayman Owners

jamescw8 · 03-07-2011, 12:27 AM

Hello, I have developed an oil leak directly from a large hexagon shaped bolt on the right rear of the engine block (images attached below).

The leak isn't where you would expect if the RMS or IMS was leaking because it is in front of the clutch housing and just behind the sump pan. The clutch was replaced a year ago.

Does anyone recognise this part of the engine and if so does the bolt just need tightening or am I looking at worse issues.

Help much appreciated!

jcb986 · 03-07-2011, 04:26 AM

Not sure...I believe that is the oil pump. Maybe you just need to replace the crush ring on it....

jamescw8 · 03-07-2011, 07:39 AM

You could be right! Its hard to make out which part it is, in the parts catalouge and explosion diagram. There is suprisingly limited info about the oil pump online. If this was to be replaced the engine oil would presumibly need to be replaced?

Cheers!

JFP in PA · 03-07-2011, 09:59 AM

Quote:

Originally Posted by jamescw8

Hello, I have developed an oil leak directly from a large hexagon shaped bolt on the right rear of the engine block (images attached below).

The leak isn't where you would expect if the RMS or IMS was leaking because it is in front of the clutch housing and just behind the sump pan. The clutch was replaced a year ago.

Does anyone recognise this part of the engine and if so does the bolt just need tightening or am I looking at worse issues.

Help much appreciated!

The oil pump on an M96 is next to the water pump on the front of the engine, and shares the same metal gasket with the water pump. That looks more like the main intermediate shaft tensioner, which fits inside the crankcase near the flywheel.

jamescw8 · 03-07-2011, 12:10 PM

You are spot on JFP in PA. I hope this isnt a sign of problems with IMS? Do you think it just requires tightening up or is that a bad idea? Not quite sure why it has randomly just started leaking!

Cheers.

JFP in PA · 03-07-2011, 12:22 PM

The tensioners have a crush ring on them (you can see it near the hand in the small pic.) that is replaceable. An oil leak at the tensioner seal is not a sign of impending doom; it is just an oil leak. Now comes the fun part; you cannot replace the crush ring without removing the tensioner; and you cannot remove the tensioner without first locking the engine at TDC:

And then securing the cams so that they do not move (jump time) when the tensioner is released:

After which you can unscrew the tensioner, put on new crush ring and a new o-ring on the shaft, and re-torque it. Simple, isn't it? Before going through all this, I'd suggest making sure it is torqued to begin with.

jamescw8 · 03-08-2011, 06:14 AM

Fingers crossed it just needs tightening up! Any ideas on the torq setting for this tensioner?

Many thanks!

JFP in PA · 03-08-2011, 10:18 AM

80 Nm, or 59 Ft. Lbs.

jamescw8 · 03-08-2011, 10:54 AM

Just looked through the manual and it is a chain tensioner for cylinder bank 1-3. Torq setting is 80Nm so I will make sure it is torqed to that. If I were to remove it, they say nothing about making sure it is at TDC.

JFP in PA · 03-08-2011, 10:59 AM

When you release the chain tensioner and remove it, the cam chains are going to go slack. Pressure from the valve springs and cam followers are going to cause the cams to move in relation to the crank, throwing the cam timing off, which is often disastrous if not reset properly. By putting the crank at TDC, then locking the cams mechanically, nothing can move, so when the tensioner is returned, everything is where you left it. This is the exact same procedure used when the IMS is changed, and for the same reasons.

jamescw8 · 03-09-2011, 05:47 AM

Fair point! If I do need to replace it I will follow any instructions to a t! If I am not replacing it and only torqing it slightly to 80Nm, would this throw the cam timing off still or am I safe to just goahead and tweak it? Cheers.

JFP in PA · 03-09-2011, 09:56 AM

If you just re-torque the tensioner, no precautions are required; they only come into play if you need to pull the tensioner to replace the crush washer and o-ring……..

jamescw8 · 03-11-2011, 01:20 AM

Many thanks JFP in PA! Your knowledge has been a great help. I will let you know how I get on this weekend! Cheers.

insite · 03-11-2011, 04:23 AM

that is indeed a tensioner, but it's the one for the passenger side head, not the main IMS chain. the main IMS tensioner is the one that sits horizontally.

JFP is right that there is SOME risk of losing time when you remove the tensioners, but you actually have to jump a tooth somewhere to have this occur. if you set the engine at TDC, the camshafts will not move when you take out the tensioner (they are unloaded here, i have tried it).

in addition to the crush ring, there is a small o-ring about half way down the tensioner; this should also be replaced if you R&R the tensioner.

i would personally not be concerned at all about R&R the tensioner without locking the cams. i would, however, be 100% certain that i was locked at TDC.

one more note: it looks like you have some oil coming from further up the motor & this may be contributing to your leak. my guess from your pic is a spark plug tube.