Vehicle Preventive Maintenance
FAQ for 7xx/9xx/90 Cars
See the section Buying
a Used 7XX/9XX for related information.
maintenance after purchase: When I buy a used
740 (87-92, are preferable) these are the items that I would immediately
change/replace before placing the car into service. (Assuming the car had
been checked out thoroughly first)
Radiator/hoses/thermostat - replace radiator
with metal unit. Flush coolant. I've added the plastic overflow tank to
my list of replace/repair on 740's with >100K miles, and especially on
the Turbo cars. The overflow tanks are cheap enough to include in the general
cooling system maintenance program. [Editor's Tip:] See the
of Coolant discussion for information on components that age and break.
[Tip: Ralph Haber] Under coolant items
to replace, I'd add replacement of the heater control valve. Since
this appears to be made from the same plastic as the radiator, it'll eventually
fail, perhaps catastrophically
(recent experience). Unfortunately, I had to replace with another
plastic unit (Volvo part) but would rather a metal unit be fitted, if possible.
Plugs/wires/cap/rotor/timing - replace
check as required (don't forget to check the advance mechanism)
Replace the O-rings on the distributor,
and the camcover gasket including the half-moon ends
Throttle body - clean
Belts - all three, replace
Set valve clearance
Timing belt - replace with Volvo unit.
When you do the timing belt replacement, it's relatively cheap to replace
the cam, intermediate and crankshaft oil seals.
Oil - change oil/filter unless previous
change can be substantiated.
Oil Filter mount O-rings...only $7 or
so but labor is expensive...can be done yourself
Change the auto trans fluid/gasket.; Change
the rear end/differential lube .
Brake fluid - thoroughly flush
Fuel filter - replace
Check the rubber hose that connects the
tank prepump with metal fuel line; these tend to deteriorate with age.
Hydraulic engine mounts...if the pan is
less than 1/4" to the crossmember you're on borrowed time...if it touches...replace
both of them.
Transmission output shaft bushing - check/replace
as required if over 130K [This is not a problem area, just a wear issue.
There is a bushing on the output shaft of aw70 and aw71 trannys that wears
after time. I have seen it more on 240Turbos than 700's. It costs about
$200 at transmission shops.
Turbos: Turbocharger oil return pipe to
block O-ring...only $4 or so but labor again...replace the paper turbo
to pipe gasket. Check ALL, and I do mean ALL, of the vacuum or pressure
hoses in the engine compartment, especially the little one that controls
the turbocharger pressure to the wastegate...blow this one and the engine
will grenade from overboost. Check condition of rubber in harmonic balancer.
Wiring (83-87 cars): Get busy with a roll
of electricians tape or plan on rewiring a lot of stuff...many wires under
the hood have had their insulation broken down over the last 10 years...not
so bad if they're ground connections, but eventually even those wires/connectors
will corrode to the point of not connecting. Evil things will befall thee.
[Note: see prior notes above on Baked Wiring Harness problems, and connector
Last, but not least, check to see if the
splash shield under the engine is whole, or even still there!! That shield
helps to keep the engine clean and air flow correct....it's relatively
cheap from RPR or whoever.
1990 740/760 Problems. [Query: Any "special" problems
I should look for in a 760 of this vintage?] [Reply:] I bought my 89 740
(non-turbo) at approx. the same mileage. Some items since then have been
the radiator (replaced
with an all-metal unit as opposed to the factory plastic tank version),
water control valve, the FI ECM, motor
mounts and now at 175k miles the steering rack needs to be replaced.
None of the above parts alone are insanely expensive, except the FI unit,
so if you do your own work, it's not too bad. A recurring problem on my
car is that the power
window switches keep flaking out and I'm too cheap to get a new set
and too tired of opening them up and cleaning them. [Editor's Note: see
the section on engine
wiring harness problems with 83-87 7xx cars.]
Storage Tips. [Query:] I will be leaving the country in another
month and have to put my Volvo in storage. What type of preparation should
I do to the car before I leave and what should I do on my return? I plan
on disconnecting the battery and I may even have a friend start the car
once a week...the storage will be outside with a car cover and will be
sitting for the majority of a Phoenix summer.
Shorter-Term Storage Hints: [Response
1: Paul Seminara] Shouldn't be a huge ordeal to store a car in Phoenix
through the summer. Just keep it in the shade!! (car cover 'll work) Make
sure the tires are out of the sun, too. I don't think it's too good
to just start the car once a week, unless you do a full warm up cycle with
some good driving. I think you'd be better off just dumping some fuel stabilizer
in, filling the tank all the way, changing all the fluids, squirting some
oil in the cylinders, turning it over, put new plugs in and remove the
battery (you may do the battery monitor thing, but I'd be wary if I couldn't
eyeball it once in awhile) and let her sit. [Response 2: John Erickson]
All the things Paul mentioned are good things to do, but you can get away
with little or nothing. If you can get someone to drive the car once a
month, you don't need to do anything else. If no one is going to touch
it for six months, then you should put it on blocks (tires get flat spots
that won't run out - especially in the heat), top off the gas tank and
disconnect the battery. The battery will be dead when you get back, but
it will recover after a jump start.
Long-Term Storage Hints. [Query:]
I am going to put my brick ('91 940gle) on the block (storage) for approx
12 - 18 months in the garage. Anything else I need to do other than
the suggestions from the board. The existing timing belt has 47000 miles
on it and the manual recommends timing belt replacment at 50000, should
I go ahead replace the belt now and then put it in storage, or can I replace
the belt after I put the brick back on the road 18 months from now. if
I leave the existing belt in the car, will the existing belt break when
I attempt to re-start the engine 18 months later (the 940gle is an interference
engine - major repair if the timing belt breaks). Any particular areas
require extra attention before I put the car in storage?
[Response: JohnB] Store the car and replace
the belt after a few hours of running after you take the car out of storage.
Reason is that the belt is supposed to be replaced at x miles (50k in your
case, my 90 B230FT is supposedly 45k in the chilton book but I still figure
50K) or if the car has been stored for 'any length of time,' whatever that
means. Apparently the idler pulley puts a dent or fix in the belt, a reverse
dent or set, and the belt reliability suffers. As you already know,
the engine (non-DOHC 4 cyl) is non-interference, even if the belt snaps
when you start the car or after a few hours, no damage to the engine will
You might consider using amsoil marine
synthetic lubricant for storage...the marine oil has a hefty anti-corrosion
package that is ideal for long term storage. One should probably change
the engine oil before storage, as well as the engine coolant.
I like to 'fog' the cylinder walls with
marine storage lube, i.e., pop the plugs, squirt lube in the holes, put
the plugs back in, disconnect and ground the ignition coil secondary, pull
the fuel relay, and spin the engine a few seconds while blowing lube in
the throttle body.
You can either drain the fuel tank and
drop a dessicant bag (onna string...you will need to remove it!) into the
fuel filler neck...it should be pretty well sealed unless the cap is defective,
or you can use a quart of gas stabilizer mixed in with a full tank of gas.
18 months is a long time for gasoline, however, and you'll probably find
yourself dumping the gas so it's better to have less gas than more to dump.
If you have a non-steel gas tank, I'd run the tank as low as practicable,
add the fuel stabilizer, run the engine a few minutes to distribute the
stabilizer, and then pull the fuel relay at the storage site when you fog
Plug every orifice on the car you can....squirrels
or whatever will find them if you don't. Find a couple bags of dessicant
and put them in the car...clean the car real good before you close it up!
If you have someone to air out the car every 3-6 months (no start!) and
reactivate or replace the dessicant bags, so much the better.
Best case is if you can find a giant plastic
bag to put the entire car in, suck the air out of the bag (wet/dry vac
works good, and then bleed dry nitrogen into the bag. There are storage
bags available, obviously you have to drive the car into the bag, look
in the back pages of Autoweek or Motor Trend or whatever. Or check
The Army learned a good lesson from the
Israelis on bagging entire tanks/armored battalions...The tanks start up
every six/12 months with nothing more than new battery packs (not a small
deal....a modern tank takes 4-6 BIG batteries, like the size of those on
semi trailer rigs.)
Take the battery out and sell it....you'll
need a new one in 18 months almost no matter what you do with it.
to Remove Tobacco Smell From Newly-Purchased Brick? I had the same
problem and used a product sold by Sam's club called "Odor Ban". Sprayed
it on the seats and carpets before I used a regular upholstery cleaner.
worked very well for me.
Preventive Maintenance. It would be wise to inspect the voltage regulator/brush
unit (VR/BU) for wear while the alternator is removed from the engine bay.
The small slot screws which retain the VR/BU can be quite difficult to
remove, especially if your car is driven in the "rust belt". The VR/BU
sells for around $70.00 and can be obtained at any Bosch supplier. I apologize
for not being able to give you a part number, but the VR/BUs are selected
to match particular alternators and, if my memory serves, later model 240s
were fitted with one of three Bosch models (depending on trim & accessories).
One tip I can provide is to avoid cheaper, third world units as these can
fail prematurely! When re-assembling the VR/BU with the alternator body,
place a small dab of anti-seize compound on the retaining screws. This
will make it easier to remove the VR/BU in the future. The rubber bushings
used in mounting the alternator, power steering pump, and a/c compressor
tend to require replacement after about 7 years.
[Tip: Editor] Remove your alternator
and take it to an automotive electric shop, where they can rebuild it for
around US$70 including new bearings, brushes, voltage regulator and a complete
Trap Preventive Maintenance. [From RPR:] On four-cylinder non-turbo
engines, the flame trap (a replacement for the old PCV valve in the "positive
crankcase ventilation" system) prevents engine backfires from igniting
in the crankcase. However, airborne contaminants and oil residue will eventually
clog this device and cause excessive crankcase pressure. Symptoms of this
problem may include finding your oil dipstick lifted up from its entry
tube and worse, leaking engine seals. The flame trap is "buried" under
the intake manifold [between 2 and 3 cylinder intake manifold inlets.]
Do not let this discourage you. Replace the flame trap every year for trouble-free
engine performance. Also replace the hoses connected to it if they appear
bloated or "spongy" from engine oil damage. Do not use clamps to hold flame
trap hoses in place; if they are popping off, you may have excess crankcase
pressure. Also check that the vacuum fitting on the induction (intake)
manifold is open and providing vacuum for the PCV system. The fitting is
connected by a small hose to the flame trap housing.
Preventive Maintenance. See the fluid filter under "Steering"
and the notes on fluid change/filters in "Transmission"
Records. [Tip: Steve Ringlee] Zee's recent post on "Computerized
Maintenance" was very insightful. I've tried to keep two sets of maintenance
records for each car: one on my computer and one in the engine compartment.
The computer records show date, mileage, who did the work, and a detailed
description of not only the major work done but things to watch for in
the future. This is backed up by a file of all receipts (remember the lifetime
warranty on shocks? you'll need the receipt!) and warranties, etc. This
goes beyond the stamps in the Volvo maintenance book: things are described
in more detail and include work never done at the Volvo dealer, who is
other set is in the engine compartment. My father's mechanic taught me
permanent marker and white duct tape on
selected flat, cool surfaces to record routine things like:
the complete record of all fluid and filter
changes: oil, trans, diff, brake, coolant, brake fluid, power steering
When you are maintaining five cars for self,
wife, kids, in-laws, etc. it is impossible to remember what is going on.
Every time I bring one of them in for service, the mechanics at either
the dealer or Sears, etc. are unbelievably grateful that someone has made
life easier for them by posting the obvious in the engine compartment.
It also makes diagnosis a whole lot easier and keeps me from doing things
twice because I forgot that I had done the work last year. I just open
the hood and instantly know when something is due for work.
tire rotations, wheel alignments
changes of plugs, plug wires, cap &
seals and belts
air, fuel filters
replacement of relays, sensors, battery,
Mealtime Tips. [Query: After driving my Volvo, I am hungry.
What to do?] You can heat canned food ( small cans) on the engine block
of many 4 cylinder Volvo engines by removing the paper label and
placing it on the engine just under the intake manifold. The car's
cooling system regulates the block temperature, and this should keep the
can at around 130 degrees fahrenheit for whenever you'd like to stop
for lunch. In WWII, soldiers actually cooked roasts and potatoes, etc.
on those flat jeep engines on trips between posts ( I got this idea from
one of these old vets) and I believe there's actually a book out called
"Manifold Cookery" or something like that. Just keep your motor clean
and don't try to stuff cans tight into the wiring. B230's are great for
this...turbos too, but forget the frogmotors and 16v's ( no room).P. S.
This works year round!
FAQ for 7xx/9xx/90 Cars
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