P38A Problem electrics solved

Enuff · Oct 10, 2018

Well, not solved but many faults will be resolved with this little fix.
I have 3 main fuse boxes removed from P38s with electrical gremlins. There's a common fault here, I thinks so dismantled the fuse boxes.
As you can see in the pictures it's very solder heavy but still not enough to cope with massive bolt terminals, time, vibration, heat etc etc
I know this has been done before but the same fault was on all 3 boxes. The main power feed to fuse boardboard the battery which causes total shut down while driving on the motorway.....which causes poop.... then it fires back up again

Hope this helps. You will need a decent soldering iron and some time to repair.
Also, this information is just meant to inform, don't do it yourselves. You must consult a skilled blah blah blah.

Pete The Biker · Oct 10, 2018

I guess the whole board is flowed with solder in one go, and the heat absorption by the main terminals means that those joints never get as hot as they should to make a good connection.

Pete

Enuff · Oct 10, 2018

I agree...I can't get them hot enough without making the board smoke.
Pete, any suggestions on a solid mechanical fix ? I'm scratching my head.

Paul D · Oct 10, 2018

How are the threaded terminals fixed? Can you remove them, make a pad of solder on the board, then drill the solder/board and literally bolt some bolts back on, sandwiching the solder?

Pete The Biker · Oct 10, 2018

Enuff said:
I agree...I can't get them hot enough without making the board smoke.
Pete, any suggestions on a solid mechanical fix ? I'm scratching my head.

I think a low power soldering iron will cook the board, but the terminal will lose heat as fast as you apply it - maybe you need something more high powered like these https://www.ebay.co.uk/sch/i.html?_nkw=soldering+gun+150w&ul_noapp=true to pump a lot of heat in quickly.

But I have to confess that's just theory on my part - maybe someone else can confirm from practical experience.

Pete

biketeacherdave · Oct 10, 2018

You just need a higher wattage soldering iron, clean up the PCB around the terminal I mean take it back to good PCB. At the worst you can just bridge it but it don't look bad at all.
Don't apply the heat to the PCB but the terminal then let the solder flow over to the PCB. Hope that makes sense

Enuff · Oct 11, 2018

It does...
It's also a good excuse to buy more tools.

brianp38dse · Oct 11, 2018

New tools is always good

Datatek · Oct 11, 2018

Pete The Biker said:
I think a low power soldering iron will cook the board, but the terminal will lose heat as fast as you apply it - maybe you need something more high powered like these https://www.ebay.co.uk/sch/i.html?_nkw=soldering+gun+150w&ul_noapp=true to pump a lot of heat in quickly.

But I have to confess that's just theory on my part - maybe someone else can confirm from practical experience.

Pete

You certainly need a heavy duty soldering iron to resolder the terminals, but for me that is the only way to do the job. If you have made the board smoke, it will quite likely absorb moisture now, so should be sprayed with conformal coating on both sides when you have done the soldering.

Pete The Biker · Oct 11, 2018

It would be worth thinking about getting some heat into the terminals by other means before you start soldering - maybe with a hot air gun - to reduce the heat drain into them. But you would need to protect any surrounding components.

Pete

Datatek · Oct 11, 2018

Pete The Biker said:
It would be worth thinking about getting some heat into the terminals by other means before you start soldering - maybe with a hot air gun - to reduce the heat drain into them. But you would need to protect any surrounding components.

Pete

That, to me is a recipe for disaster

. A good soldering iron is all that is needed, a cheap gas powered one will do the job.

Grrrrrr · Oct 11, 2018

Datatek said:
That, to me is a recipe for disaster. A good soldering iron is all that is needed, a cheap gas powered one will do the job.

I've got one that runs off lighter fuel and it is an awesome bit of kit. An normal soldering iron just cannot handle the outdoors in this country.

Datatek · Oct 11, 2018

Grrrrrr said:
I've got one that runs off lighter fuel and it is an awesome bit of kit. An normal soldering iron just cannot handle the outdoors in this country.

By lighter fuel, I presume you mean gas not petrol? That's what I have, a real heavy duty job, was useful when working on leisure boats with no shore power.

Grrrrrr · Oct 11, 2018

Datatek said:
By lighter fuel, I presume you mean gas not petrol? That's what I have, a real heavy duty job, was useful when working on leisure boats with no shore power.

Yes, the gas one.

wammers · Oct 12, 2018

I have several soldering irons. From small 10 watt for fine board work and 25 watt for loom terminals etc. And a Weller robust 250 watt for heavy cable work. Plus gas blow lamps for anything else.

kds · Oct 12, 2018

I have several soldering irons ranging from 12 volt tiny thing to one that nearly needs two hands to lift it, not sure where it came from but it must have been my mums cos its got AM stamped on it and mums name was Alice Margaret

wammers · Oct 12, 2018

kds said:
I have several soldering irons ranging from 12 volt tiny thing to one that nearly needs two hands to lift it, not sure where it came from but it must have been my mums cos its got AM stamped on it and mums name was Alice Margaret

Silly lad that means it can only be used before midday.

kds · Oct 13, 2018

wammers said:
Silly lad that means it can only be used before midday.

Bugger thats where i`ve been going wrong ! Never get to use it before midday takes me till then getting all my bits on the the move plus all the coughing and spluttering clearing my lungs which think they are 15 years older than the rest of me !

Enuff · Oct 13, 2018

Got myself a 60watt iron for £20 and it worked a treat. Fitted between these pins like a well fitting thing. Also heated the bolts within seconds allowing solder to flow making a excellent solid joint.
Soldering Not pretty but works fine.

P38A Problem electrics solved

Enuff

Well-Known Member

Pete The Biker

Active Member

Enuff

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Paul D

Old, nackered 'n broke, but the Landy is fine . :)

Pete The Biker

Active Member

biketeacherdave

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Enuff

Well-Known Member

brianp38dse

Well-Known Member

Datatek

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Pete The Biker

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Datatek

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Grrrrrr

Technician, Bodgit & Scarper Ltd

Datatek

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Grrrrrr

Technician, Bodgit & Scarper Ltd

wammers

No longer with us, RIP

kds

Well-Known Member

wammers

No longer with us, RIP

kds

Well-Known Member

Enuff

Well-Known Member

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