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Stag

To: british-cars@autox.team.net
Subject: Stag
From: Paul Amaranth <amaranth@vela.acs.oakland.edu>
Date: Wed, 9 Sep 92 10:41:53 EDT
> Date:  8 Sep 1992  15:23 EDT
> From: whs70@dancer.cc.bellcore.com (sohl,william h)
> Subject: re: TR Stag questions
> 
> >From magnus.acs.ohio-state.edu!dstarr Tue Sep  8 14:58:02 1992
> >From: Dwight Starr <dstarr@magnus.acs.ohio-state.edu>
> > A friend of mine has just purchased a 1972 Stag.  
> >We have a few questions.
> >
> >1. Where can we find a source for information on this car?  It has
> >some kind of V8 but we don't know what it is.
> >We need repair manuals, parts sources etc.
> 
> The engine is a single overhead cam (one cam for each side of the V8)
> type that was exclusively developed and used in the Stag.  No other
> production automibile has the Stag engine.  The engine does not have
> a great mechanical longevity history as there is a significant
> conversion business in the UK that replaces the Stag engine with
> any one of several other engines, usually a Ford or GM V6 of some
> type.

Most of the initial problems have been sorted out.  Sorry Bill,
*nobody* in their right mind does an engine conversion now.  The engine
is prone to overheating problems if not watched which will result in
warped heads.  Leaks in the head gaskets can lead to corrosion
problems, particularly with the stud & bolt arrangement used to keep
the head on.  So, this requires one to:

   a) Flush the cooling system religiously.
   b) Rod out the radiator to make sure it's clear
   c) Some people replace the 6 vane water pump with a 12 vane one, but
      you have to replace the cover as well if you do this.
   d) Replace the clock with a TR6 oil gauge and watch it.
   e) Pay a lot of attention to the engine.

The overheating problems are also related to the Labour Troubles at
that time.  One of the guys in my Triumph club rebuilt his Stag engine
and pulled out 10 pounds or so of foundary slag out of his block(!).  Didn't
help his cooling system any.

The timing chains also need to be replaced every 25000 miles.  They're
single link chains which are kind of weak and they stetch.  (The tensioners
also need to be replaced).  If the chains break you have valves going through
pistons, which is not very pretty.

The crank is another weak point.  They just did a surface hardening and
quality control was nonexistant.  Some apparently weren't hardened at all.
If the journals wear, the oil pressure goes down, the timing chains aren't
tensioned (hydraulic tensioners), the chains flap and snap, there goes
your engine.  Fun.

Overall, it's a pretty nice engine that could have been great if they
had invested a little more money in ironing out the engineering problems
(but that's a whole story in itself).

> For parts and service manuals, contact The Roadster Factory at
> 1-800-234-1104.  Other parts sources in the US are: Eightparts
> in Tucson, AZ.  Eightparts phone number from an old business card
> is 603-622-1290.  Other than that, get a Hemmings Motor News and scan
> the T section for other possible sources.  Also, the UK connection
> should be considered, check for Stag info/listings in Thourohbred and
> Classics magazine.

Don't bother looking for parts from these folks.  For one thing,
Eightparts is run by a bunch of idiots.  For another thing, there are
too few Stags in the US for anyone to carry any reasonable line of
parts.  Anyone who owns a Stag should be a member of the Stag Owner's
Club in the UK.  Their newsletter contains a few tech articles, lots of
nattering about club outings and ads for the companies that actually
stock Stag parts.  They also have a spin off company  (SOC Sparess) to
supply Stag spare parts.  This is the only way to get parts for the
car. You can get a membership form by writing to 

   SOC
   Membership Secretary
   Howard Vesey
   53 Cyprus Road
   Faversham, Kent  ME13 8HD
   Tel: 0795 534376

If you get the parts manuals, there is a correspondence between some of
the TR7 engine parts and the Stag V8 (the 7 engine is 1/2 the V8, which
is one reason why everyone hates the 7 engine; it not only shared a
common development effort, it shared many of the same technical problems
as well).  Also various bits and pieces of other Triumphs (TR6, Dolomites,
etc) were used, but you need to do the cross reference yourself (buried
somewhere, I have a partial cross reference list)

SOC Spares can supply both the parts manual and a workshop manual.

> If it wasn't for the engine, the Stag is a beautifully styled 4 place
> touring car.  It can be kept running well, but damage to the engine
> (eg. timing chain failure leads to pistons hitting valves) can be
> expensive to repair.
If you're a real tech weenie, you can get to like the engine too :-)

> >2.  He is having trouble getting into first and reverse from neutral at a 
> >stoplight.  Is this just the clutch adjustment or tran problems?
> >The problem is intermittant. Isn't that fun!,
> 
> Well, I'd try bleeding the hydraulic clutch first and see if that helps.
> That's a no cost (assuming you do it yourselves) immediate possibility.
Yeah, I'd try that too.  I believe the clutch and release mechanism is
the same as the TR6.  The trans is the same too, except the 1st gear ratio
is different.

> And, of course, you should join the Vintage Triumph Register if you
> plan on keeping the car, assuming you are not already a member.
Good idea.  Also join your local Triumph Club.  My local club has
2 other Stags in it.  Useful to have a support group you can cry with.

> The Stag was produced from 1970 to 1977, but only imported to the USA
> during the 1970-73 model years.  About 25,000 Stags in total were
> built with about 3000 shipped to the USA.  Almost all the Stags in
> the USA seemed to have originally come with both the hardtop and softtops.
80% had engine warranty work, Triumph lost money on every car they sold.
Almost all had air. Power windows were standard, adjustable steering
wheel, power assist steering, power assist brakes, integral tonneau and
integrated roll bar (probably the most striking feature) were also
on it.  Generally a neat and cool car :-)

Maybe 1200 still running in the US, optimistically.  Excellent examples
can go for upwards of $15K or so, with the original engine.

If your friend thinks it's too much to handle, give me a call :-)
-- 
Paul Amaranth  Manager User Services - office: (313) 370 4541 (also voicemail)
(internet)     amaranth@vela.acs.oakland.edu  | TR8 - running (zoom!)
(bitnet)       amaranth@oakland               | Stag - engine disassembled
(uucp)         ...!uunet!umich!vela!amaranth  | XKE - in pieces

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