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Volvo Relays

Mine is a 1991 Station Wagon, 740. 140K miles. I had a no-start several days ago but it has started OK since. I suspected the fuel pump relay so I pulled it and put it back in (presumably cleaning the contacts in the process). The car has been fine since then. But I am worried about certain relays. In the front row, the K relay (central locking?) is too hot to touch; the J relay (window?) is quite hot (but not as hot as K), and the fuel pump relay is quite warm. In Brickboard I have seen two views; "Volvo relays are always hot", the other "A hot relay is a bad relay".

Does anyone have any views on this (the others are are only very slightly warm or only ambient temperature)?

Thanks,

John

Reply to
<jwjensen356
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Dunno what is normal but I don't like hot electricals. I saw a suggestion to drill some small holes in the casing... while it's off. I followed the suggestion with a new fuel pump relay 8 months ago but who knows if it will help? They did say 7 years was about normal lifespan for those (1980 265), which doesn't sound very good - seems something shortens its life.

Reply to
jg

They're made by Bosch and have circuit boards inside. When they get old the solder joints at the connector pins tend to crack and result in an intermittant connection. If you know how to solder or know someone who does, or feel like spending $15 on equipment and a few minutes practicing, it's fairly easy to pop the cover off and resolder them.

Reply to
James Sweet

If it's getting more than just a little warm, you've got a bad connection or excessive load. I failing fuel pump will draw too much power and melt the relay and connector. Also once the connector gets hot it oxidizes which causes resistance and then more heat. I suggest checking the current draw of the fuel pump, if it's pulling more than 10A it's probably worn out.

Reply to
James Sweet

The car is a l991 and it did have fuel problems in 2000. The fuel pump was then replaced and a new relay installed (date code 1999, made in Hungary).

I will replace the relays one at a time, starting at the hottest and see what happens.

Reply to
<jwjensen356

This is what it can look like:

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Regards,

Boris Mohar

Got Knock? - see: Viatrack Printed Circuit Designs (among other things)

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Reply to
Boris Mohar

Here's a link on an article I wrote, aimed at beginners, on how to solder:

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__ __ Randy & \ \/ /alerie's \__/olvos '90 245 Estate - '93 965 Estate "Shelby" & "Kate"

Reply to
Randy G.

Thanks, everyone, for great comments and suggestions. I'll do the resoldering first (I'm well experienced) and will go from there.

John

Reply to
<jwjensen356

what a brillant shot thank you

Reply to
John Robertson

It was taken with a digital camera held manually against the eyepiece of a microscope. Microscope projects image at infinity so there is no trouble with focusing. Anyone can do it.

Regards,

Boris Mohar

Got Knock? - see: Viatrack Printed Circuit Designs (among other things)

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Reply to
Boris Mohar

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