Patrick,
Both. The oil keeps pressure on the tensioner, and there is a tiny hole in
the rubber block that allows oil to lubricate it.
It seems to me that nothing is forever. That includes a spring in the
tensioner. That's why Datsun recommended swapping out the timing chain
components like every 60,000 miles so you won't have to deal with a spring
losing it's tension over a period of use.
Perhaps the problem is that folks are using the tensioners well beyond
their lifespan by not swapping them out at the same time as the chains.
As for requiring shimming of the tensioner due to a change of timing geometry,
that's another matter altogether. If the head's been severely cut then a new
tensioner spring won't do the job, so a modification needs to be done, like
these guys are doing.
Oh, one other thing. Sometimes the oil pressure to the tensioner is compromised.
Either due to a blockage from crud, or the gasket doesn't have a large enough
hole (or is completely blocking the hole), or the tensioner is loose and allows
the oil to leak from the side.
A long time ago when I was a newbie, I ignored the death rattle. Result was
holes in my timing chain cover and the valve cover when things gave way, when
someone else drove it and raced the engine.
Fred - So.SF
______________________________ Reply Separator _________________________________
>Subject: Re: 2L Chain Tensioner
>Author: "Patrick P. Castronovo" <slick1@mohaveaz.com>
>Date: 7/16/2001 4:48 PM
>
>I am confused. Is the Oil in the Tensioner for Oiling the Tensioner,
>or for keeping pressure on the Tensioner?
>
>Is there a spring also in the Tensioner, if so, would it not lose it's
>Tension after time from the heat of the oil?
>Then when the Chain stretched would the Spring become ineffective?
>
>Or did they put in a spring that is long enough to compensate for the
>Chain stretch, and the Rubbing block wear, with just the right amount
>of spring pressure so not to wear the rubbing block prematurely.
>It sounds pretty complicated to me. Makes me think they were pretty
>savvy in using the Oil Pressure to take up the slack of the Chain, and
>eliminate many of the problems they faced otherwise.
>Pat
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