Dead Volvo EC15B, help and advice needed.

[Muz]

Are there any signs of other electrics having been in the machine like missing switch blanks or drilled holes in consoles etc ?

[v8druid]

that's in that state because the contacts were too dirty to make a good circuit and has been generating heat in some order - also a possible reason for blowing the correct size fuse in the first place - only answer there is replace with new - waste of time even trying a new fuse in that way too corroded.
Get your self a new fuse rail

http://www.ebay.co.uk/itm/2-4-6-8-10...item4ac0bff832

these guys are a great source of leccy bits - http://www.ebay.co.uk/usr/towzatronics and cheap

[Loucastel]

Hi Muz, no holes anywhere, it was used by a small general builder, Thanks Druid, I will change the holder and fit new fuses, just hope there is no other underlying reason, will update soon,

[Muz]

Because those fuses are not original AFAIK .. someone has fitted them to get round some other problem that isnt working correctly.

50 Amp is a full load for something juicy like a starter. If there were to be a fault in a very basic circuit almost to the point of a direct short on the turn of the key ... it would melt even that, so you are looking at an issue where someone has bypassed all the machines support electronics to feed just the starter.

My guess is that its ECU has failed or some other timer relays .. and someone has plumbed in a direct feed from the key to the starter, because they didnt want to pay volvo £bucks for the ECU or didnt know which timer relays had failed

The reason is .. that , that engine is quite a poor starter from cold without heat, and needs heat from glow plugs to get ignition easily. So ... it would mean holding the starter on for about 40 seconds before it will even think about firing when the temp gets below 0 degrees or so .. thats long enough to melt 'that' fuse under that sort of load

There are a couple of threads on here about that ECU if you do a search .. I could be wrong .. but its a viable hypothesis IMO

[v8druid]

Because those fuses are not original AFAIK .. someone has fitted them to get round some other problem that isnt working correctly.

50 Amp is a full load for something juicy like a starter. If there were to be a fault in a very basic circuit almost to the point of a direct short on the turn of the key ... it would melt even that, so you are looking at an issue where someone has bypassed all the machines support electronics to feed just the starter.

My guess is that its ECU has failed or some other timer relays .. and someone has plumbed in a direct feed from the key to the starter, because they didnt want to pay volvo £bucks for the ECU or didnt know which timer relays had failed

The reason is .. that , that engine is quite a poor starter from cold without heat, and needs heat from glow plugs to get ignition easily. So ... it would mean holding the starter on for about 40 seconds before it will even think about firing when the temp gets below 0 degrees or so .. thats long enough to melt 'that' fuse under that sort of load

There are a couple of threads on here about that ECU if you do a search .. I could be wrong .. but its a viable hypothesis IMO

If that's the case Muz, I'd wire in a control switch for the heaters, detented to off and give it some heat before going to crank. ECUs are notoriously expensive !! wire and switches are peanuts, in comparison - switch, powering a decent relay, feeding the heaters - job done

[AndrewMawson]

50 amps seems fairly low current for a starter motor even on a small engine. I reckon the glow plugs are a more likely candidate for that fuse, starters tend to peak at a few hundred amps inrush current for the first fraction of a second and that would pop that fuse cleanly (rather than the overheated mess that it is)

[Muz]

50 amps seems fairly low current for a starter motor even on a small engine. I reckon the glow plugs are a more likely candidate for that fuse, starters tend to peak at a few hundred amps inrush current for the first fraction of a second and that would pop that fuse cleanly (rather than the overheated mess that it is)

You could be right but the op said there were two .. one 50 amp and another 30 amp with a fifty amp fuse in it, although he didnt say how it was wired. The battery on those machines is quite small, it only measures about 10x9x9 inches and it doesent take mach to run them down. As long as there wasnt a short im not sure it would blow. Also the op stated the machine was totally dead .. no dash lights or anything, so it must be carrying power to everything.

[v8druid]

50 amps seems fairly low current for a starter motor even on a small engine. I reckon the glow plugs are a more likely candidate for that fuse, starters tend to peak at a few hundred amps inrush current for the first fraction of a second and that would pop that fuse cleanly (rather than the overheated mess that it is)

Totally agree with Andrew - no way would this be a main feed to starter ....... fuse'd want to be a couple of hundred amps!

You could be right but the op said there were two .. one 50 amp and another 30 amp with a fifty amp fuse in it, although he didnt say how it was wired. The battery on those machines is quite small, it only measures about 10x9x9 inches and it doesent take mach to run them down. As long as there wasnt a short im not sure it would blow. Also the op stated the machine was totally dead .. no dash lights or anything, so it must be carrying power to everything.

Quite likely a heater plug fuse, but they too draw a considerable current Muz, probably more than the 30/50 amps in the fuse holdersand normally have a direct from battery feed.
More likely to be a main fuse supplying a smaller distribution fuse box.
The main thing to establish is - are they OE and if they are, WTF are they supplying.
Would've thought if they're not OE, it would be obvious they've been 'cut in' to the loom?
So difficult without some decent pix of the general layout/area they're sat in to make a judgement, without actually seeing the beast

[Muz]

Well every days a school day .. Just had an EC15B come back in this afternoon and had a quick look .. turns out they are OEM after all

and this is what they should look like, a 40 and a 50 .. clipped to a panel on the rear firewall and I must say in all the years of ownership of these units, Ive never had any incident with these fuses.

[Loucastel]

Hi guys, yes the pics of the fuses you put up are as mine used to look, all oe, not added, well, put a new fuse holder in temporary, new fuse, and it turned over, wanted to start but didn't, then it decided to blow that fuse too, new fuse, eventually got it started and running, but it is not right, the 40 amp fuse feeds the little fuse box just under the seat, wipers, heater, ignition etc, so we still have a problem somewhere, if it was working, I would dig a nice big hole and bury the bloody thing, thanks again guys, keep those ideas coming.

[Loucastel]

Just found out the 50 amp is the fuse for the glow plug things! lower amp fuse for the little fuse box under the seat.

[AndrewMawson]

Just found out the 50 amp is the fuse for the glow plug things! lower amp fuse for the little fuse box under the seat.

Told you so - told you so

[Loucastel]

Told you so - told you so

Hi Andrew, Haha, so now tell me why the 40 amp would keep blowing when all it is doing is running light's, ignition and stuff, cheers.

[ianoz]

With the JCB8080 i have , They zippy tied the glow plug wire to something . With the vibrations it had worn though and blew the fuse.Check the wiring for something like that .

[AndrewMawson]

Hi Andrew, Haha, so now tell me why the 40 amp would keep blowing when all it is doing is running light's, ignition and stuff, cheers.

Because either a wire or a terminal is shorting to chassis, or one of the supplied devices has an internal short. Look for chaffed wiring as a favorite