'83 240 GLE fuel pump relay

Does anyone know where the in tank fuel pump relay is on a '83 240?
I'm trying to isolate a problem, car stalls after driving perfectly for
a short time on hot days, seems the in tank pump is gone but i am
trying to rule out any other faults. High pressure pump workes fine.
Any other advice would be appreciated
Thanks
Josh

 

I just went through fuel troubles in my '83 245.
I was going to say on the firewall, under the carpet on the passenger
side. That's the relay for the main pump. I hadn't thought about the
relay for the in-tank pump.
I'll be watching this thread...

 

I've never understood the in tank prepump to have its own, separate
relay.

 

If this is true then it pretty much confirms that the pump itself is
dead. Looks like i've got some replacing to do. Thanks for your help.

 

Dunno about the 240, but I thought it had a dual section relay module like
the 740 does. Those are notorious for becoming intermittent when warm -
cracked solder connections. It matches your symptoms well enough that I
think you should verify whether yours is one of the affected relays and if
so, where to find it.

Mike

 

Definately sounds possible, but I think since the time the car cools is
directly proportional to the time the car runs, a cracked solder is not
too likely.I will still check it out though. I am also a little
confused. Doesnt metal expand upon being heated, therefore making a
break in a circuit less likely to show itself in hot weather?

 

I don't know the details of why the failures are more common when warm, but
it is that way not only in Volvos but in Hondas, which have the same
problem. (In Hondas, the relay assembly is known as the "Main Relay.") If it
means anything, the cracks show up as circular hairlines in the solder where
the heavy relays are mounted. When my eyes were younger I could see the
cracks in mediocre light, but now I need sunlight and a magnifying glass.
(Come to think of it, I need sunlight to find the magnifying glass!).
TeGGeR's excellent Honda FAQ site has a good picture at
http://tegger.com/hondafaq/mainrelayoperation/badmainrelay.html

Mike

Mike

 

It does, but just the fact that movement takes place when it gets warm
can break a circuit. It's always a good idea to resolder the relay even
if it isn't causing problems, it will some day.

 

Dont just resolder it remove the solder and replace the solder with new
silver solder ,quickly so as not to cook the joint and solder .

 

i shall have a look at the relay in the morning, try resoldering it and
see if it affects the car at all. I've gotta do some soldering under
the hood anyway. We are getting some freakishly cold summer weather so
it may be some time before i know if this is the fault . Thanks for
everyones help

 

I favor reusing the old solder with a dab of rosin. I don't know where to
get rosin flux separately any more (the tin I had was from a store that went
out of business when I was a kid), so just a touch of rosin core solder to
freshen the joint is a good substitute. Failing that, remove the old solder
and start over as you say. I agree - just reflowing without flux produces an
oxidized (dry) joint. Not as bad as a cracked one, but not still not as good
as you want.

Mike

 

I opened the relay and bingo! cracked solder. However, the cracked join
was not actually linked to any other component, it was one that was
holding the relay coil in place. Could this have been the culprit? The
crack was quite large, maybe it was enough to let the coil vibrate and
in turn the plates. i resoldered the second join to this coil just in
case the cracked solder had also damaged the second join - this one was
linked to the battery power. I wont know how the relay is going until i
get some more hot weather, any suggestions on how i can safely test the
relay?

 

No need to use silver solder, ordinary rosin core tin/lead electronic
solder works fine.

 

my volvo mechanic told me the other day, the lead content
in newer soder is not as high as in older soder, making it
not "breathe" and expand/contract with heat, thus cracking after
limited cycles.....the s80's are having trouble w/some sodered
components....

 

The new manufacture stuff is made with lead-free solder. I'm all for
reducing the use of toxic materials, but lead-free solder is crap.
Wouldn't surprise me if the waste levels increased due to lower reliability.

 

The body of the relay, called the armature is where these cracks usually
occur. The armature is the par of pump current switching circuit.



Regards,

Boris Mohar

Got Knock? - see:
Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca

void _-void-_ in the obvious place

 

Indeed. Just look up Tin Whiskers.





Regards,

Boris Mohar

Got Knock? - see:
Viatrack Printed Circuit Designs (among other things) http://www.viatrack.ca

void _-void-_ in the obvious place

 

I've confirmed that the relay is working properly by testing for
voltage at the pump. voltage exists, but the pump doesnt run. Thanks
to all for help isolating the problem, i am in possession of a new
pump, i just need to install it this afternoon.
Would any of you know a good way to get fuel lines off the pump? They
are jammed on too tight to just pull off. The guy who sold me the pump
suggested heating the fuel lines, is there a way to do this without the
risk of igniting the fuel?

 

I usually use an impact wrench to get the banjo bolts out. Be careful
not to twist the fittings and kink the lines.

 

Thanks for the suggestion, i followed the fuel line until i found a
banjo bolt and undid that instead of messing with the connection at the
tank, fed the line through and that gave me enough play to remove the
hatch. I replaced the pump with no problem and now hear the soft buzz
which i couldnt hear with the old one. Ran the car for about an hour
today (quite hot) and it went beautifully, also fixed up a little bit
of chugging at idle, guess the fuel pressure was too low.