Cold solder joints

G

Garry Beattie 22 years ago

G'day guys.

I have a 1984 Rover 3500 EFI Vanden Plas which is giving me a little problem at present.

Sometimes I will be driving along and the motor shuts off. Stops completely. When I try and start it again it will not start. It cranks over OK and there is plenty of power, however it will not start. I have had a listen but can not hear the injectors ticking while this is happening.

After a couple of minutes it starts again and drives as if nothing was wrong. As an extra clue it only seems to happen when I am coasting to a stop at a set of lights or coming up to a corner.

I had a very similar problem with my last Rover, an 83 3500SE EFI, and it turned out to be the computer, but it would stop and not start again for, sometimes, up to 12 hours later.

A couple of people have suggested it could be cold solder joints in the computer which is supposed to be fairly easy to fix, and is a common problem with this model Rover.

Can anyone please elaborate on this more. Can I fix it myself with a soldering iron? Are the cold solder spots easy to locate?

Could it be any other reason apart from cold solder joints in the computer?

Vote

A

AWM 22 years ago

Some SD1 had ribbon cable inside the distributer which failed giving the exact symptoms you descibe BUT I don't think your car has this type of ignition system more likely the later AB17 style which generally either works or fails completely.

The other thing it could be is the oil pressure switch on the SD1 and some

80s/90s FWD Austin-Rovers the fuel pump relay is wired through the oil pressure switch -- the oil pressure switch being a special type which works the opposite way from the normal type --- ie: the contacts are "no" not "nc"

Vote

P

Peter Hill 22 years ago

Can you hear them when it's cranking over normally with the ignition disconnected (unplug the module)? I usually use a sounding rod (mine is 18" of 1/4" round Perspex) to listen to stuff like this. Place end of rod against injector and other end against ear.

Some are very easy to spot as they are dull grey and not shiny like the rest. Others are just a thin faint dull ring round the joint and need close inspection with a magnifying glass to see. If you have a

15/17w soldering iron with a 1mm tip and the ECU is easy to remove and disassemble you may as well use a solder sucker to remove all solder from joints on power transistors in the ECU and then re-solder them. If you don't have experience the ECU is not a good thing to learn on as overheating of solder pads on circuit board can cause the pads to detach.

Do you have a spark? It is common for the earth joint to an alloy heat sink base to be made using a high silver content solder. These joints can fail giving symptoms just as you describe.

Sticking or coked idle air control valve if the motor has ECU controlled idle speed. Check the base idle by unplugging the idle air valve.

Check mixture ratio and O2 sensor if fitted (I think it's way too old to have one).

-- Peter Hill Spamtrap reply domain as per NNTP-Posting-Host in header Can of worms - what every fisherman wants. Can of worms - what every PC owner gets!

Vote

D

Dave Plowman 22 years ago

Dunno - I'm 6ft tall, and the leg room is only just adequate for me.

Rover P6s used to be supplied with spacers to raise the seat height - it might be the same trick would work with an SD1.

I don't think the seats collapse anymore than any other car, but you could always compare the driver's and passenger's ones.

Vote

G

Garry Beattie 22 years ago

I agree with Dave.

I have a newer car. I just purchased the Rover 3500 VP EFI because it is an absolute joy to drive. Very comfortable and, with a twin exhaust system, very nice to listen to. A bit like a fun car for me!

It was, I believe, the last model of the genuine Rovers. All the others have been made by Honda or BMW. I looked at an 817 and did not like it at all. I also looked at a 75 and, while it looked nice, it didn't do much for me.

So I set off to find a very nice VP with specific search criteria. 18 months later I found it and purchased it. Now I am looking to iron out a couple of small bugs it has in it.

Thanks for those who have replied to date.

Best regards

Garry Beattie Australia.

Vote

Cold solder joints

Join the Discussion

Didn't find your answer?