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RE: Oil
I had exactly the same problem with my 2.5 PI Spitfire 3 months ago. The
engine had been rebuilt with phosphur bronze alloy valve guides and run
up a few times. At most it had had 1 hours use. I'd run it for a while
setting up a new throttle linkage. The next day I went to run it and the
engine did about � a turn before seizing. Luckily with Triumph Six's the
valves don't meet the piston. But I had snapped two rockers and bent 6
push-rods.
On investigation I found all the seized valves were Inlet Valves. I put
this down to the use of "Graphogen" assembly paste, which had not been
washed away due to the use of valve stem seals on the inlet valve
guides. After a good wash in "Hyperclean" with wire wool (Valves and
valve guides) it ran ok. This car had had some old petrol sitting in
the bottom of the tank. Wether this contributed to, or caused, the
problem I don't know.
Altogether not a pleasant experience. Thoughts of new cranks, blocks,
and pistons had flshed before me. I would'nt minded so much but that
engine had just had brand new Stanpart Crank, Block and Pistons.
I take the point about the valve guide not having been run in being at
the root of the problem.
Richard Brake
[email protected]
-----Original Message-----
From: Angus Holliday [SMTP:[email protected]]
Sent: 10 March 1999 00:52
To: Koehler
Cc: [email protected]
Subject: Re: Oil
At 03:31 PM 3/8/99 -0800, you wrote:
>In response to:
>
>>This is a convoluted response to your input. I used to
believe all the
>hype on Castrol (yes, I said Castrol) - I have had FOUR MAJOR
engine
>failures with valves seizing up in the valve guides running it:
>
>72 Stag
>79 Spitfire
>83 Chev 350 V8
>71 Ford 302 V8 in a boat
>
>It has happened over a 10 year period, but Castrol is the ONLY
common
>denominator.
I think I can explain the cause of your problem...but I
definitely feel it
isn't Castrol. We have used Castrol for over 18 years in
too many vehicles to mention without a problem. But on to the
cause...I
recently had the same problem in my Jag XJ6 , the
car had a warped head when I purchased it. The head work was
done by our
regular machinist and re-assembled and ran well.
The car didn't get driven much for about 5 months, at which
point it went to
a shop for stereo install. The first day they started it
to drive it in the shop 2 valves stuck and bent. I removed the
head and
took it back to the machinist. The cause? Ethanol spiked
gas which is required here from Sept to May. The gas goes bad
in a matter
of months. When a car has new valve guides the
valves get glued into place. With 20K miles or so on the engine
the valves
have enough clearance to not stick. Our machinist
has seen about a dozen cases so far. Usually the person removes
the engine
for rebuild, it takes a while for them to get it back running ,
and the gas that remained in the tank gets used to start and run
the car.
Usually it will take a few runs before the problem shows up.
Usually it will be on a start up the morning after the engine
has been run.
With American cars the result is often a bent push rod..if you
are lucky.
After the head is removed it is difficult to drive the valve
from the guide
even with a heavy hammer; however if the valve is heated with a
propane
torch if will fall out. The "glue" will be very apparent.
Moral of the story:
Do not use old gas...even 4-6 months old.
especially if it
is "oxygenated". Drain the tank and while your at it, blow out
the line and
change the filter. We are also seeing cases where this gas is
glueing the
mixture needles to the jets, or at least leaving a
gluey deposit on them that prevents the carb from working as it
should (bad
idle esp) Before "new" gas this wasn't a problem.
The whole idea of the oxy fuel is pretty stupid as 1) it costs
more 2) the
gas mileage is worse and 3) in all modern cars the
O2 sensor automatically re-adjusts the mixture anyway. With a
small number
of old cars there is a slight pollution advantage....
if they are not re-adjusted by the owner to compensate..All in
all a pretty
non- cost effective way to fight pollution...but profitable for
the
makers of the additives! (and they have been known to express
their thanks
with campaign contributions!) Oh well I digress..
Hopefully this is not an issue for Non-American Stag owners.
>PS - I run Mobil 1 in my Camaro - 51K miles with no problems,
however I
>wouldn't expect problems yet. Consumer Reports did a study
which
>basically said all the oils are the same (including
synthetics).
Their test oil was not run long enough for any differences to
show up..5-7 K
miles as I recall..
If so,
>why does GM REQUIRE synthetics in Corvette and V-8 Camaro?
It is better stuff,the same is true for the gear oil and diff
oil. There
are potential problems in running it in other than new engines
though..sometimes it detects leaks..hehe
W.A. Holliday
Stag Specialists N.A.
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