Timing chain tensioner oil leak

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Blaise
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Timing chain tensioner oil leak

Post by Blaise »

It seems that I have an oil leak at the timing chain spring retainer bolt. It is the horn that protrudes from the left side of the motor. It appears that there is a crush washer there. Is there any reason that I should not just remove the bolt and replace the crush washer?

On another note, my new water pump just failed...Grrr
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T.Hanson
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Post by T.Hanson »

You can visit realoem.com., timing and valve train (engine) to see what's behind the shoulder nut. It's not a garage door spring, but you should anticipate it pushing out when the hex cap is free of the threads.

So who made the new (?) water pump to top quality OEM specs ? If I were King, the company would send you a refund (as if you'd want another top quality replacement from them), and five hundred bucks for having to screw around twice.

Ha !
Luis A.
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Post by Luis A. »

Hi Blaise,

Of course you mean the right side of the motor (passenger) and it's a screw plug/shoulder nut, as T.H. wrote, not a bolt. Make sure the leak is really from that joint and not from the nearby lower chain cover / upper cover / block / head joint which is a common leak area. Get a new cruch washer and apply the specific torque as listed in the manual.
Luis

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GripGreg
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Post by GripGreg »

Wow, Blaise.
It seems the crush washer is the way to go with the correct torque;
but, question;
is the water pump impeller metal or some form of plastic?? :?
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Mike W.
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Post by Mike W. »

Those always leak, sooner or later if you just assemble them with a standard crush washer. I wrap both the threads of the plug and around the washer with teflon tape and have had pretty good luck with that. The problem is you're trying to stop engine oil pressure from leaking past flat surfaces with a metal washer. It should have been an O ring in there like on the oil filter, but it's not.
Mike W.



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Mike W.
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Post by Mike W. »

GripGreg wrote:Wow, Blaise.
It seems the crush washer is the way to go with the correct torque;
but, question;
is the water pump impeller metal or some form of plastic?? :?

I've never seen a M30 pump with a plastic impeller. M50x yes, M30, no.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
GripGreg
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Post by GripGreg »

OKEY DOKEY!! :lol:
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wkohler
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Post by wkohler »

Mike W. wrote:
GripGreg wrote:Wow, Blaise.
It seems the crush washer is the way to go with the correct torque;
but, question;
is the water pump impeller metal or some form of plastic?? :?

I've never seen a M30 pump with a plastic impeller. M50x yes, M30, no.
There are pumps made by a French company that have a composite impeller. I put one on my 533 after the Graf failed within 400 miles (one year exactly - just missed the warranty).
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Falkenberg
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Post by Falkenberg »

Mike W. wrote:The problem is you're trying to stop engine oil pressure from leaking past flat surfaces with a metal washer.
Are we talking about the large bolt (17, 19mm, can't recall) that keeps the chain tensioner spring in place? afaik there is oil but no oil pressure there. The oil kept there is supposed to form a shock absorber for chain movements, together with the small piston.

Some oil will poor out when you remove the bolt. After you assemble, the small oil reservoir should fill up again automagically when the engine runs. You might hear some chain noises at first start. Some people have the good practice to manually fill it prior to starting, but you have to remove the valve cover for that.
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Mike W.
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Post by Mike W. »

Yes I am talking about that large plug. I'm not sure, but I think it is under pressure, it's got the little hole in the tensioner piston for lubing the chain even. Regardless, teflon tape on the threads and the washer help seal it and prevent leaks.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
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