C
Chris Bowne
After starting my son's 1990 Volvo 740 GL wagon for a periodic "run up" and
drive around after a bout two months sitting idle (son's serving over in
Kuwait, car's with me while he's away), the car stalled after about 1/2 hour
of driving and idling. Initially started right up and ran great. Died
sometime while I was away from it for a short time working on the son's
other Volvo, an 83 240 Turbo. The 740 doesn't want to restart - cranks but
no catch. Did try to catch briefly on some starting fluid. Timing belt
seems OK, as I can see the through the oil filler opening on the cam cover
that the cam has moved after cranking. Suspect either one of the two fuel
pumps or their associated relays have crapped out. Basing that on total lack
of fuel smell in engine compartment or at the exhaust pipe after extended
cranking trying to restart. I'm temporarily at a disadvantage w/o a shop
manual for this car. Will get one ASAP, but trying to fix sooner if I can
get some basic info.
Both the main fuel pump fuse and the in tank pump fuse seem OK, and contacts
in fuse block look OK.
What sort of load resistance should I see on the load side of the fuses in
the circuit? Presumably something low if the circuits are calling for the
pump to be running, I would expect to see the pump motor DC resistance
there.
Is there a convenient place to check fuel delivery pressure, like the
Schrader valve on late model Fords?
Can someone tell me the location and pin out of the two relays, so I can
troubleshoot, including temporary jumpering of the relay contacts, which I
believe are a common problem with these cars, just like the 240 series? I am
also suspecting possible corrosion in some contacts in the relay connector
plugs, as its been very wet and humid here since the last time the car was
run.
Yes - there is plenty of fuel in the tank - I added a few gallons as the
first step of the troubleshooting process, and I know tank was fairly full
to start with.
Chris Bowne
Stonington, Ct
drive around after a bout two months sitting idle (son's serving over in
Kuwait, car's with me while he's away), the car stalled after about 1/2 hour
of driving and idling. Initially started right up and ran great. Died
sometime while I was away from it for a short time working on the son's
other Volvo, an 83 240 Turbo. The 740 doesn't want to restart - cranks but
no catch. Did try to catch briefly on some starting fluid. Timing belt
seems OK, as I can see the through the oil filler opening on the cam cover
that the cam has moved after cranking. Suspect either one of the two fuel
pumps or their associated relays have crapped out. Basing that on total lack
of fuel smell in engine compartment or at the exhaust pipe after extended
cranking trying to restart. I'm temporarily at a disadvantage w/o a shop
manual for this car. Will get one ASAP, but trying to fix sooner if I can
get some basic info.
Both the main fuel pump fuse and the in tank pump fuse seem OK, and contacts
in fuse block look OK.
What sort of load resistance should I see on the load side of the fuses in
the circuit? Presumably something low if the circuits are calling for the
pump to be running, I would expect to see the pump motor DC resistance
there.
Is there a convenient place to check fuel delivery pressure, like the
Schrader valve on late model Fords?
Can someone tell me the location and pin out of the two relays, so I can
troubleshoot, including temporary jumpering of the relay contacts, which I
believe are a common problem with these cars, just like the 240 series? I am
also suspecting possible corrosion in some contacts in the relay connector
plugs, as its been very wet and humid here since the last time the car was
run.
Yes - there is plenty of fuel in the tank - I added a few gallons as the
first step of the troubleshooting process, and I know tank was fairly full
to start with.
Chris Bowne
Stonington, Ct