1970-1972 common problems

From: Kevan Morrison (kcmorrison at postoffice.worldnet.att.net)
Date: Sat, 05 Apr 1997 13:46:17 -0800

                                      1971 Chevrolet Monte Carlo  
                                 Problem Areas and Suggested Solutions  



There are three particularly prevelant areas of rust on the '71 Montes
that need to be examined: 
1) Front lower fenders - rust in this area is sometimes missed because
of the lower trim strips, and           also if the car is painted in a
darker color.  Repair panels are available at Year One and The Paddock.

2) Rear lower quarter panels - this area tends to start rusting around
the drainage holes from inside the car, and can be detected by using a
flashlight to examine the interior inner fenders.  For extensive rust
damage repair, I've seen rear Monte repair skins sold at Year One.

3) Upper forward interior door/door hinge area (where weatherstripping
meets door) - this is a common 
rust area not only for Montes but particularly for Malibus, Camaros,
Firebirds, etc.  The weatherstripping often wears away, allowing the
water to eventually lay in and work it's way through the door.  I have a
rust hole on my Monte's passenger as big as the tip of my little finger;
I've seen some in other Montes and Camaros almost three inches across. 
The fix; body work and new, solid weatherstripping (ex., SoffSeal).

A fourth (and particularly nasty) area that's not so noticeably is the
forward passenger side floor pan area. Per my discussion with a POR
(anti-rust treatment) factory rep, the GM "A" bodies had a tendency to
leak water into the car at the lower windshield seal.  Because this area
is covered by stainless steel trim, the leak can go unnoticed; the water
seeps down into the car (frequently in the area of the heater) and will
eventually cause the floor to rust through if not corrected. In
addition, a leaking heater core or connection can do similar damage,
though the smell of leaking antifreeze (and disappearing coolant) should
make this problem more detectable.  My '71 Monte has an apparent
windshield leak, with a resultant 3" X 6" hole in the forward passenger
side floor.  I've seen two '70 MCs with similar (and more extensive)
damage in the same area.


Due the age of the 1st gen Montes, good replacement grilles are
difficult to find.  The worst of the three years is the '71; since these
grilles are nothing but chromed pot metal, they don't hold up very well
to begin with.  What appears to make the '71 grilles more difficult to
obtain is the design and metal thickness of the grille; seems that they
tarnish, corrode, and just plain fall apart more easily than the '70 and
'72's.  The very few '71 grilles that I've seen were so badly corroded
that they had areas that crumbled between my thumb and forefinger.  I
understand that there are suppliers that can provide NOS '71 MC grilles,
but I've yet to find one, and I'd bet that the cost would be quite


Dash air vents - after 25+ years of use, these are normally pretty
shot.  The outside vents are particularly suspect to wear; look for
broken vent vanes or vent axle pins.

Console - on console-equipped cars, the console glovebox lock is
frequently shot (or even jammed). The locks are easily obtainable at
Year One, The Paddock and other similar suppliers.  And, YES, the
console gear selection indicator (for automatic-equipped cars) IS
illuminated; if your gear selector display doesn't light up at night,
the problem is probably a burned out bulb or a loose ground wire. 
Pretty easy to fix; the console gear indicator area removes with a
phillips screwdriver, and the wiring is easy to service.


Motor mounts - I understand that the BBC engines had a tendency to break
their motor mounts, so much that Chevrolet issued a service bulletin
instructing service personnel to install a security-type cable that
connected the block to the frame.  Whatever - I've noted on my car and a
72 MC BBC fan blade damage that indicated significant contact with
something other than air.  Moral of the story; check out the motor
mounts, and replace them if they look worn.  If you need to replace the
motor mounts, you may want to check out the freeze plugs while you're in
there, too.

Carburetor - if the Monte is Quadrajet-equipped and you experience
particularly hard starting during cold starts, you are probably
encountering a fuel leakage problem.  The plugs at the bottom of the
primary and secondary fuel wells start to leak, and the fuel drains
away, causing hard starting, as well as a overrich running condition
when the engine is running.  Cure - epoxy these plugs.  The epoxy (and
rebuild kits) can be obtained at most good auto parts stores.

Also on the Quadrajets for the 1st gen Montes; the fuel line is normally
a solid piece of tubing from the fuel pump to the carb, and the fuel
filter is internal.  This is where many folks (including myself)
encounter an unpleasant surprise; probably because of the fuel line
design (inflexibility), engine/line/carburetor vibrations, etc., the
fuel line/carburetor connection has a good tendency to strip out the
threads, preventing you from obtaining a good connection.  Fear not;
there's several methods of correcting this problem:

1) Many auto parts stores can sell to you an insert that will rethread
the stripped-out portion of the carb,
and provide a nipple-type connection suitable for attaching a short
piece of neophrene hose to your fuel line.
To install, you thread the insert into the carb, connect the hose, cut a
corresponding short piece of the end of the fuel line, and reattach the
other end of the hose to your fuel line.  You now have a solid (but
flexible) reconnection of your fuel line to your carb, and the vibration
from the fuel line to the carb has all but been eliminated.

2) The solution mentioned above may not appeal to those folks wishing to
obtain a pure stock look to their engine compartment.  The Carb Shop in
California (specializes in Quadrajet rebuilds) will attempt to heliarc
and rebuild the damaged thread area IF you did not attempt to first
correct the problem with an insert.

3) I've seen several BBC Montes where the fuel line has been replaced
with a flexible fuel line, and the in-carb filter as been replaced with
an inline filter.

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