>
> The first 10 seconds or so after I start the car, the engine is very noisy.
> After this ten seconds or so it quietens down. The noisy is the "no oil
> anywhere" noise but goes after the oil passageways are under normal pressure.
> the question is why do we get this noise?? Worn bearings, maybe, but I think
Normally, such a noise (loud knocking-ish) at startup is a sign of seriously
worn rod bearings, and absolutely no oil pressure. The Truimph 1500 engine
is notorious for this, especially the Midget variation. The filter is mounted
in such a way that, with the wrong filter type/design, the oil drains out
through the loose bearings. On cold start, you have to refill the filter
before the pressure comes up. (BTW, you didn't say, what type of car is this?)
> I had a 73 MGBGT which took about 10-15 seconds to reach full pressure
> (which was very good) after initial start-up. This engine was not that noisy
> during this start-up period as it had very good bearings etc.
A B should get oil pressure straight up. The usual cause of a delay in this
era B is a missing "riser" tube on the oil filter mount; a approx 2" tube
the sticks up to the bottom (top as mounted) of the filter. This keeps the
oil from draining.
> I use Amsol synthetic oil and amsol oil filters. You can leave in the oil
> for up to 12 months and need to change the filters every 6 months. These
> filters easily outlive and outfilter normal filters, but I think maybe it is
> clogged. So I'll change it and let you know if this "start-up" noise
> gets better.
>
I've used AmsOil, though I currently use Mobil 1. However, I used exactly two
Amsoil filters, both for one day each. You are correct that they filter
"better". They use a much tighter mesh in the filtering medium. The reason
I tried two filters, then went back to my standard was due to this tighter
mesh. I was not at all happy with the 15 pound oil pressure drop these
filters caused.
Note this was over ten years ago, and it was not a lab test. After listening
to the sales pitch, I put one of the filters on my B. My B's always had
75 pounds @ 1500 rpm. After the filter, it showed 60. So I tried a second
filter. Still 60. Then I went back to my usual (Mann), and it was right
back at 75. Things probably have changed since then, but I'm not going back.
On the off chance you do have a 1500, the design thing I refered to above is
a one-way valve in the filter. 1500's really need to have this to slow down
the oil drain. Look at the business end of the filter. There should be a
rubber flap visible through the outer holes. If these holes are wide open,
look for a different filter.
>
> Cheers Dennis
Randy
randy@taylor.wyvern.com
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