Oil leak from timing chain tensioner

Drew20

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a question for you: can I take the timing chain tensioner assembly from the head and replace the seal washer and reassemble everything without upsetting the timing?

I've got a reasonably bad oil leak which looks to be coming from the tensioner. The tensioner piston sits in its own little pool of oil, so I assume that a failed seal washer is letting this oil fall onto my garage floor.

I'd rather not lift the valve cover off unless I have to, as this looks more involved than on my old E24... but obviously don't want to risk timing slippage, etc

Cheers
 

m5bb

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Yes, you can remove the tensioner on the M30 motor and replace the seal without affecting the timing.
I recommend not moving the engine while it's out.
It's not unusual for those seals to leak. Don't be afraid to tighten it. Not sure what the torque spec is?
 

sfdon

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You can dress the opening to the piston bore with a stone to make sure it's flat.
 

sfdon

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Just to be very clear-
Removing the "screw plug" to replace the aluminum crush ring will release the spring pressure. Allowing the oil to escape will disable your hydraulic cam chain tensioner. Smart people don't start engines without cam tensioners working. If you lose your tension you can restore it by pouring small amounts of oil into the #1 cam area and hand manipulating the piston with a long screwdriver until the air in the system is replaced by oil.
 

Drew20

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Think that's clear Don, valve cover needs to come off as the spring tensioner working on its own might let the cam slip a tooth. So I need to lift the cover to manually pump oil into the oil piston tensioner once I'm done reassembling the tensioner with the new seal.

Cheers both

(and I need a rubbing stone)
 

sandhu

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Take the car back to the garage that sold it to you , they should fix it under the warranty
 

pat cooks

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it is also quite common for the timing cover gasket to leak from this area, now that is not an easy job! hope it is just the tensioner, try tightening it first, they are often loose.....
 

Drew20

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Yes this is true, if it's the timing cover, top or bottom, then I'll live with it for now

I'm hopeful though as it leaks a lot after a drive for a few days and then stops, which I think is the "pool" the tensioner piston sits in emptying out
 

Drew20

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Just to close this one out, I've had the cooling system apart recently and, whilst I was there, I finally addressed this oil leak also. I took dizzy, upper timing cover and chain tensioner off, applied some TLC and rebuilt with new gaskets/washer and a bit of hylomar where the timing cover sits on the CH gasket, just above the tensioner oil reservoir.
Finally got it all back together yesterday and took car for a good hot run, and no leak!

Disproportionately pleased about this
:)
 

mulberryworks

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So, this Hylomar of which you speak, is it some form of RTV?
I'm not familiar with that brand but it seems like there are a number of different products with that name.

Ian
 

Stevehose

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I've used Hylomar its good stuff, just make sure you get the stuff made in UK, the usa version doesnt seem as good. Originally developed by rolls royce. Ebay.
 
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Drew20

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Hylomar blue, it's a non-setting gasket sealant, for when you're not 100% the paper gasket is going to be enough. Turns out my dad was involved in its development, when he worked for RR, or so he says
:rolleyes:
 

E9Wayne

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Hi Drew, Don and others, I've been researching an oil leak I have now that appears similar to this one. I originally thought it was coming from the oil pressure switch, based on more oil coming down between the motor and tranny and under the tranny tunnel, or so I thought, but I did a removal, inspection and tightening with a plumbers sealant last weekend of the switch and the leak is still there. I've uploaded some photos showing the timing chain tensioner area from underneath. The oil is dropping down from there, and I think it was there all along as it appears to leak directly onto the AC compressor and from there my garage floor. I'm not clear on what the fix is here. If the leak is at the bolt area, do I simply remove and reinstall with new washer or sealant? I'd like to do this myself or perhaps borrow my handy friend Chris Ohmes for a Saturday or Sunday work/beer project...thank you in advance, all...


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pat cooks

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with this type of oil leak you must look for the highest and most forward sign of oil as it will always go down and back, it could be a bad copper seal ring on the tensioner or loose tensioner, it could be the gasket between the front cover and engine block, quite common, or from the front of the head gasket, not very common, I would clean it all with break cleaner or similar and then take it for a drive before inspecting it, you can get a UV sensitive dye to put in oil or water and then look with a UV lamp if you need to,
 

sfdon

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Pat has it down- clean everything first and then off for a drive.
Only one easy answer and thats the crush washer so do it now, clean like crazy and go for a short drive.
Have paper towels ready. slowly and carefully look ........
 

pat cooks

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carefully and slowly wipe with a white kitchen roll, checking as you go as that will will show a thin film of oil that you may not be able to see, works for fuel as well, when the paper stays clean you have gone past the leak, my money is on the lower front cover just behind the chain tensioner, worth checking the M6 bolts but don't overtighten,

another common leak is because people machine heads without the front timing cover attached, I have seen two rocker cover gaskets fitted but with the front of one cut off to make up the difference, or a tube of sealer smeared over the top of the head, never works............. just falls into the engine and blocks up oil ways!
 

billpatterson

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Hylomar blue, it's a non-setting gasket sealant, for when you're not 100% the paper gasket is going to be enough. Turns out my dad was involved in its development, when he worked for RR, or so he says
:rolleyes:

Hi Drew

Do you use Hylomar Blue also along the surfaces of the paper gaskets? I tend to use gasket adhesive or RTV but this product intrigues me and likely best to use only one when installing paper gaskets.

Regards,
Bill
 

Stevehose

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I've used Hylomar on gaskets, smear some on your finger tips and pull the gasket through, you just want a very light thin coating with no excess. Work quickly as it sets up fast on your hands. Acetone cleans it up. Get the version made in UK, not the USA.

Hi Drew

Do you use Hylomar Blue also along the surfaces of the paper gaskets? I tend to use gasket adhesive or RTV but this product intrigues me and likely best to use only one when installing paper gaskets.

Regards,
Bill
 
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