Timing chain tensioner oil leak

[kc944]

Hi,

I have just discovered oil dripping from the big chain tensioner nut on the left bank (cyl 1,2,3)of my engine (1998, 996 UK, RHD). It seems to be coming from where the nut screws into the engine and not dripping from further up. I understand replacing the seal is fairly cheap and simple to do but can I just go ahead and unscrew it or do I risk messing up the chain tension/valve timing? Are there any special precautions to take before removing it?

Thanks!

[RFM]

If you are talking about the chain tensioner seal, yes you can messing up the timing, the best is to lock the camshafts with a special tool.

[jetbox]

If you are talking about the chain tensioner seal, yes you can messing up the timing, the best is to lock the camshafts with a special tool.

HI,

Its looks like I have a leak similar to this. Does anyone have any experience of changing the tensioner seal.

How do you lock the cams?

What tooling is needed

thanks

Jetbox

[996noob]

If you are talking about the chain tensioner seal, yes you can messing up the timing, the best is to lock the camshafts with a special tool.

HI,

Its looks like I have a leak similar to this. Does anyone have any experience of changing the tensioner seal.

How do you lock the cams?

What tooling is needed

thanks

Jetbox

Me too, I have a leak at the big nut as well. Would be helpful to know what is involved in changing the seal (is it an aluminium crush washer?).

[rb101]

yes, it's just a crush washer.

Rick

99 996C4

87 944S

[JFP in PA]

If you are talking about the chain tensioner seal, yes you can messing up the timing, the best is to lock the camshafts with a special tool.

HI,

Its looks like I have a leak similar to this. Does anyone have any experience of changing the tensioner seal.

How do you lock the cams?

What tooling is needed

thanks

Jetbox

$600-$800 depending upon the source…………

[rb101]

To change the chain adjuster crush washers, the engine only needs to be locked at 1 TDC. The cam tools are only needed to remove the cam covers, you will need a 32mm (1 /14 inch) socket to remove the adjusters. I just changed out my IMS chain adjuster this weekend, you will lose about 1 cup of oil in the process. The 1-3 adjuster can be seen from the bottom, for the 4-6 you will need to unbolt the A/C compressor to get access to the adjuster.

Rick

99 996C4

87 944S

[RFM]

The special tools are needed for pre 03 M96 engines: 1) to hold the camshafts in place while removing the valve covers, except by the both separate front bearings, the shafts are only hold by the covers inside bearings which are build as a one part unit, the tools prevent the shafts to jump off timing. ( from 03 the shafts are hold by separate bearings, the covers can be removed without tools) 2) they are needed to work on the gearing of the shafts (loosen and fasten) 3) work on the timing chain/adjuster to prevent off timing jump created by a loose chain.

Use the TDC pin on the front of the engine, to lock the crankshaft and the lock tool on the rear of the camshafts, the timing will always be as it should without problems. Boxer engines can be placed on TDC in two different positions, depending which cylinder bank, TDC END COMPRESSION is what you need and difficult to see without removing the valve cover, with the tools it's piece of cake and 100% safe. Without the tools is it a matter of luck, it can end badly.

[slbates]

The special tools are needed for pre 03 M96 engines: 1) to hold the camshafts in place while removing the valve covers, except by the both separate front bearings, the shafts are only hold by the covers inside bearings which are build as a one part unit, the tools prevent the shafts to jump off timing. ( from 03 the shafts are hold by separate bearings, the covers can be removed without tools) 2) they are needed to work on the gearing of the shafts (loosen and fasten) 3) work on the timing chain/adjuster to prevent off timing jump created by a loose chain.

Use the TDC pin on the front of the engine, to lock the crankshaft and the lock tool on the rear of the camshafts, the timing will always be as it should without problems. Boxer engines can be placed on TDC in two different positions, depending which cylinder bank, TDC END COMPRESSION is what you need and difficult to see without removing the valve cover, with the tools it's piece of cake and 100% safe. Without the tools is it a matter of luck, it can end badly.

RFM

Aircraft Spruce sells a neat little gizmo that is foolproof for determining TDC. It will whistle when #1 is on the compression stroke. This is fairly easy to determine by turning the engine with a ratchet with all plugs removed. I first saw this used at the motor barn at the local FBO many years ago.

http://www.aircraftspruce.com/catalog/topages/compressionwhistle.php

[RFM]

You are right about that, similar systems are also included with cylinder leak test device, most of the forum users are enthusiasts and have not the experience and tools, experience is the mean part of knowledge, to work on engines as a pro. Any intervention seems simple at a forum but it is unfortunately not, they not always see the potential consequences of their, well meaning, interference. A shop manual and the right tools are essential and the absolute minimum to help compensate the lack of experience. If it was all so easy, mechanics and workshops were then no longer necessary.