Any Advice, Part 2!

[Laird Scooby]

Originally Posted by Chris152

Found it, I think! It's right up behind the glove box, just a few inches beneath the dash, a green box. I tried to press it together as best as I could, very hard to tell as it's so far out of the way and I have to lay on my back looking up from the bottom of the footwell - I can't figure how to get the thing off its harness, and don't want to break it trying.
Anyway, it still won't start! Is the next thing to check if power is reaching the pumps? Multimeter arriving later today.

I think you have to physically remove the glovebox Chris, if you look on that link i sent you it shows how to bypass the relap to get the pumps running, try that before getting too involved with the multimeter.

PS - once you can actually see the relay, you'll notice there are usually two tabs holding it in place on the socket. Usually if you can hold the socket and then wiggle the relay while pulling it, you can jiggle it past the tabs and out of the socket. Alternatively lift the tab one side with a screwdriver, pull then lift the other tab and pull and that hasn't failed me yet, just a lot more fiddly.

[Bugjam1999]

Chances are it’s the fuel pump relay, they don’t last forever- or, rather, the soldered joints inside them don’t last forever, a lot of the time a dead relay can be revived by resoldering the joints inside it.

Anyway- remove the glovebox by taking out the 6 or 8 screws you can see around the rim when the glove box is open, then pull it forwards to remove (this is easy and quick)

Remove the relay then follow the instructions linked to in a previous post to jump each fuel pump individually to check they work- a big strong paper clip bent into shape will work for this - and if the pumps run, then it’s the relay. If the pumps don’t run then more investigation will be needed.

There are a few things that are worth keeping in the car for breakdowns like this, even with no mechanical knowledge they can be swapped as a test. I suggest you keep:
Fuel pump relay
Ignition amplifier
Full set of fanbelts
Bulbs
Fuses (not many petrol stations have torpedo style fuses anymore)

Others may suggest more items.

Cheers

[Chris152]

Originally Posted by Laird Scooby

if you look on that link i sent you it shows how to bypass the relap to get the pumps running, try that before getting too involved with the multimeter.

Are you referring to jumping the fuses that Richard Ford describes in the link, Dave?
'I have been having fuel pump problems for a few months with my 1990 240. It just wouldn't start one morning and I saw that it wasn't getting any power to the fuel pump at the fuse panel. I jumped the wire to another fuse outlet and the car started.'
That method's described in Haynes but the position of the fuses is different to what they say. Our fuse is in position 4, do we link the left-hand connectors at positions 3 and 5 to achieve this?

Sorry - struggling with my computer here, as well! Just lost the rest of this post.
I now see that the jumping occurs on the relay itself, Bugjam. I was thinking you jump the fuses as per Haynes for 1983 and 84 LH-Jetronics. I need to go and read about how to do the jumping. If you thought my mechanics was poor, my electronics is way worse.
I've read and re-read that link but can't find anything about how to jump the relay connections themselves, I'm sure I'm missing something.

Give me a little time to try to get this clear in my head and I'll be back!

ps If it's a good idea to have a spare, maybe I can save myself struggling to test the relay by buying another and just plugging it in? If that solves it, we need another as the spare; if it doesn't, we probably already have a aspare.
I'm assuming ours is K Jetronic, as that seems to be the one that fits our car's specs (attached image, from Brookhouse).

[Bugjam1999]

Ok, there are two ways of testing the fuel pumps - one by jumping across at the fuses and one by jumping across at the fuel pump relay plug.

This page is pretty comprehensive and covers both:

https://www.prancingmoose.com/volvorelays.html

Buying a new fuel pump relay is a good idea, it's worth having one as a spare anyway, consider buying a new ignition amplifier and fan belts at the same time.

Cheers

[Laird Scooby]

Originally Posted by Chris152

Are you referring to jumping the fuses that Richard Ford describes in the link, Dave?
'I have been having fuel pump problems for a few months with my 1990 240. It just wouldn't start one morning and I saw that it wasn't getting any power to the fuel pump at the fuse panel. I jumped the wire to another fuse outlet and the car started.'
That method's described in Haynes but the position of the fuses is different to what they say. Our fuse is in position 4, do we link the left-hand connectors at positions 3 and 5 to achieve this?

Sorry - struggling with my computer here, as well! Just lost the rest of this post.
I now see that the jumping occurs on the relay itself, Bugjam. I was thinking you jump the fuses as per Haynes for 1983 and 84 LH-Jetronics. I need to go and read about how to do the jumping. If you thought my mechanics was poor, my electronics is way worse.
I've read and re-read that link but can't find anything about how to jump the relay connections themselves, I'm sure I'm missing something.

Give me a little time to try to get this clear in my head and I'll be back!

ps If it's a good idea to have a spare, maybe I can save myself struggling to test the relay by buying another and just plugging it in? If that solves it, we need another as the spare; if it doesn't, we probably already have a aspare.
I'm assuming ours is K Jetronic, as that seems to be the one that fits our car's specs (attached image, from Brookhouse).

Not quite how Richard Ford describes Chris, re-reading the contents of the link i posted it appears i was looking at another link which showed how to jump the relay contacts directly in the socket.

Yes, you need the green one as described by Brookhouse, yours is the K-Jetronic and is certainly worth trying on a substitution basis. If it doesn't clear the fault, you have a new relay and a (potentially) good spare to carry in case.

[Chris152]

Relay ordered, finger crossed.
I feel we should be working through the problem, but it's also good to recognise your limits and it'll be nice to have the car back on the road - then we can get on with the brakes!

[Chris152]

Originally Posted by Bugjam1999

Ok, there are two ways of testing the fuel pumps - one by jumping across at the fuses and one by jumping across at the fuel pump relay plug.

This page is pretty comprehensive and covers both:

https://www.prancingmoose.com/volvorelays.html

Buying a new fuel pump relay is a good idea, it's worth having one as a spare anyway, consider buying a new ignition amplifier and fan belts at the same time.

Cheers

That link's really helpful, Bugjam - thanks. As our relay fuse is No 4, would we connect 3 and 5? And is it good to buy a piece of wire with crocodile clips either end for that purpose?

I didn't buy the other bits yet but will, once this problem's sorted - I can only focus on one thing at a time, and hate parting with money :-)

[loki_the_glt]

Originally Posted by Chris152

That link's really helpful, Bugjam - thanks. As our relay fuse is No 4, would we connect 3 and 5? And is it good to buy a piece of wire with crocodile clips either end for that purpose?

I didn't buy the other bits yet but will, once this problem's sorted - I can only focus on one thing at a time, and hate parting with money :-)

PM me and I'll send you a set of jumper leads - Male/Male, Female/Female and Male/Female Lucar connectors - for this sort of work; cover the postage and I'll be happy. That way you'll have a set of "break-out" leads. A lot cheaper than buying a piece of wire as you were proposing.

[Chris152]

Originally Posted by loki_the_glt

PM me and I'll send you a set of jumper leads - Male/Male, Female/Female and Male/Female Lucar connectors - for this sort of work; cover the postage and I'll be happy. That way you'll have a set of "break-out" leads. A lot cheaper than buying a piece of wire as you were proposing.

Thank you, Loki, that's really generous of you. Pm on its way!

[Laird Scooby]

Originally Posted by Chris152

Thank you, Loki, that's really generous of you. Pm on its way!

It certainly is and they will almost certainly be much better quality than those available commercially as they won't be made to a price or a time-scale but made how they should be!