1800: Fuel Gauge not working

[MAMDaveM]

Hi All,

The fuel gauge on my P1800S is not working.

The symptoms are that when powered the gauge needle moves from the far LHS to about empty... needle moves when receives power.

The Sender is OK (new one and it checked out).
The wire connecting the sender to the gauge has also checked out OK.
The gauge is receiving 10V from the regulator.

There is definitely fuel in the tank (about 3/4 full).

Any ideas?

Thanks!

[Ron Kwas]

Dave;

If its a P1800 or 1800S, it is an early model without Voltage Stabilizer and instrument is supplied by Ign 12V...late 1800E (late dashboard had the VS)...so I'm unclear from your description which model and configuration you have...but in either case, have a look here: http://www.sw-em.com/Fuel%20Gauge%20Notes.htm
...and if its a later E or ES model with VS, look also here: http://www.sw-em.com/voltage_stabilizer.htm

Good Hunting!

[MAMDaveM]

Problem solved, poor earth connection at sender

[Ron Kwas]

Dave;

Thanks for feedback...but it's still not clear to me which model vehicle it was...

Cheers

[MAMDaveM]

Hi Ron,

My Volvo is a 1963 (December) build P1800S, power supply to fuel guage from ign 12v.

I've been working on another problem today and your ignition troubleshooting information "Volvo Ignition from Scratch" has been invaluable. Many thanks!

The symptoms of the problem are.... the engine is running fine whilst stationary (albeit I can't get it to idle below 1500 rpm) and it revs fine. As soon as I try to drive it after a short period it displays fuel starvation like symptoms, loses power and stalls and can't be restarted until for 30 mins or so.

The fuel pump is working, There is fuel in the fuel bowls when I check as soon as it stalls. I've in any case fitted new fuel floats since one of the original ones was operating too low and was not adjustable.

When trying to restart it, immediately after it stalls, there is a spark from high tension lead from the coil but no spark at the individual plug leads.

I have the (original) Bosch JFR4 distributor, with no vacuum advance, which has been modified at some time in the past to electronic ingition (Pertronix Ignitor D572).

I have checked the primary and secondary ignition coil resistances and think they are OK, from memory 4.5 Ohms on the primary and 10,000 Ohms on the secondary. I have access to the coil positive as someone thought it was a good idea to cut the armored cable to fit the electronic ignition.

The distributor cap and leads are new (but not the rotor arm, this has just been cleaned up).

I've checked the operation of the centrifugal advance and there is no spring resistance. Plan to dismantle it this afternoon.

I think this is the root of the problem.

Would that make sense to you?

with best regards

Dave

[arcturus]

Does it still have a condenser. Not sure if electronic ign still fitted? if it has condenser try changing for new one.

[MAMDaveM]

It still has the electronic ignition so no condenser.

Interestingly I took the distributor out this afternoon and dismantled it. No springs present!

I've probably find it very difficult to get replacements.

[Ron Kwas]

Dave;

Thanks for the kind words!

Symptoms of being able to rev, but running poorly under load (especially when you've checked for and have plenty of fuel in bowls) do suggest an Ignition issue...I've had similar symptoms (OE ign 122) and it was the Condenser breakdown, probably through moisture ingress over time (idled OK but insufficient spark under load, when there is more mixture compressed in Combustion Chamber which spark must pierce through), so I do agree with Arcturus, BUT no Centrifugal Advance is definitely a sign of a Distrib issue...and I can't say how that is playing with an Elec Ign Module)...I'd concentrate troubleshooting efforts there...

Good Hunting!

Edit; Our responses passed in the ether...Elec Ign may have a provision for advance based on RPM, so may not need Cent Adv...but I'd check ign module manufacturer data to verify.

Edit 2; You should probably start a new thread with appropriate title so it can be found when searching...

[MAMDaveM]

Just to finish off this thread

The solution to the ignition problem was to replace the electronic ignition module.

I'll post a summary of the issue in a new post so other can learn from my problem.