Bongo cut out, black smoke, ok on driveway

[Chief Brody]

Hi all. Hope someone can maybe point me in the right direction here. Due to circumstances my Bongo has sat on relatives drive for 4 months and hasn't moved. The Bongo is a 1998 Friendee and was originally winter pack. It looks like the converters changed it so the right hand side battery works as a leisure battery and operates the fridge, lights etc. I confirmed this by disconnecting the drivers side battery.

Anyway, the drivers side battery was flat and looked very old. I replaced this. All seemed well and the bongo started fine on the driveway. Sadly, as I left the driveway, the engine spluttered and stopped, leaving the bongo stranded on the road. It wouldn't start and wheezed as it turned over. I tried everything I could think off. I even disconnected the leisure battery and, perhaps due to coincidence, the bongo started not long after (only barely) I quickly reversed back into the drive and parked. The bongo started fine the next few times I tried (with the leisure battery reconnected) but I was far too paranoid to even take it to a garage in case it cut out. I should also mention that there was a ton of black smoke when it was turning over after it cut out on the road. When it's parked, you wouldn't know there was a problem. Starts up fine and moved on drive ok. I was trying to avoid calling someone out as money is a little tight. I should also mention that the leisure battery will likely need replaced as it is sitting on 12V and wont rise when connected to the charger. Also, when I first put the new drivers side battery in, nothing happened when I turned the key just as it did before I replaced battery. I disconnected the passenger side battery and the bongo started. After that the bongo started with the passenger side battery connected. All very confusing to me. Any help offered will be much appreciated.

[g8dhe]

Without measuring the voltages of the batteries when everything is switched off and then again when the engine is running, then its a bit difficult to advise what might be happening.
However, have you tried getting it started on the driveway and then leaving it to warm up for 20 minutes or so before attempting to drive it, if its been left all sorts of things can go wrong, machines are designed to be used not left standing rusting and corroding away.
Its quite possible that both batteries might be damaged if it was left with them flat, but many other things can go wrong as well!

[Chief Brody]

Thanks for the reply. Is it possible that a bad leisure battery could be causing this problem despite the starter battery being brand new? I'll try letting it run for a good 20 mins before attempting to drive it. Really paranoid about it cutting out and blocking the road again though.

[g8dhe]

Its possible if the Split Charge Relay is faulty or if the LB is flat and is causing a loss of backup supply to the ECU, however loss of backup supply doesn't normally cause the engine problems you mention, but you will get an error light (glowplug flashing).

[Bob]

Might be worth charging both batteries from the mains then see if they are holding charge before using Bongy.

Good luck. [-o<

[mikeonb4c]

I tend to associate black smoke more with fuelling issues but not sure if thats the case here. As Geoff says, try seeing if it will run at tickover and warm up, then see if it will rev in P (perhaps in D with footbrake on so you can backload the engine a bit but don't overdo the revs). Report back on results. But could be fuel injector related, though i'm no techie so its just a guess.

[rita]

I tend to associate black smoke more with fuelling issues but not sure if thats the case here. As Geoff says, try seeing if it will run at tickover and warm up, then see if it will rev in P (perhaps in D with footbrake on so you can backload the engine a bit but don't overdo the revs). Report back on results. But could be fuel injector related, though i'm no techie so its just a guess.

You dont want to rev the engine in drive with the foot brake On [-X

[mikeonb4c]

I tend to associate black smoke more with fuelling issues but not sure if thats the case here. As Geoff says, try seeing if it will run at tickover and warm up, then see if it will rev in P (perhaps in D with footbrake on so you can backload the engine a bit but don't overdo the revs). Report back on results. But could be fuel injector related, though i'm no techie so its just a guess.

You dont want to rev the engine in drive with the foot brake On [-X

Sorry, forgot to say 'gently' but hope that'd be obvious. But there's no problem as long as common sense is used. And the idea is to check how the engine behaves under load. As a mechanic, you'll understand that. As a pilot, its what's done quite normally as a run-up check.

[Chief Brody]

Sorry for radio silence. Life has been 'funny' as of late and the Bongo slipped down my list of priorities. I've been tinkering with the Bongo off and on and finally got it out of the drive last night for a quick drive. Bought a decent battery charger and got both batteries up to charge. Also checked all under bonnet fuses. Still a few things to look at. The starter battery measured 14.3V with engine on so alternator seems ok. Since it was charged last week it's still holding at 12.75. Have suspected a parasitic draw though as it did drop quite a bit last week. I think my multimeter may have became faulty as I'm getting a zero reading when checking the draw of the battery. Learning as I go here and will keep the thread updated as I go. Thanks for all the help.

[Chief Brody]

Bongo seems to be driving ok here. Got the Bongo back home. Was fine during the 7 mile drive. Checked the batteries last thing and they were holding charge at 12.61.

[Chief Brody]

Quick question if anyone has time. I removed my leisure battery to access abs sensor and went for a drive today with it all removed. What confused me was the fridge and lights still worked with the engine running and not running. When I was testing other things a while back with starter battery disconnected, the leisure battery ran all these. Why are they still running with no leisure battery? Any ideas?

[g8dhe]

When your alternator is spinning it raises the voltage on the starter battery and causes the Split Charge Relay to operate and charge the now no longer connected LB, however everything is still connected to the the +ve terminal clamp of the unconnected battery and so it remains powered up all the time the SCR is operated, stop the engine and the relay opens and disconnects everything again. It can take 30 minutes or so before the voltage on the SB falls below the SCR cut-off point hence why it continued for a while after the run.

[Chief Brody]

As usual you are really helpful and I thank you for that. Very interesting information. Unfortunately I just checked and the fridge and cabin lights are still coming in despite the bongo not having been on for nearly three hours. It was originally a twin battery setup but was altered when converted, way before I got it. There's a ryder tf1170-3 relay between the two batteries. I'm just worried that there's a chance of being without hookup that they starter battery will drain rather than only the leisure battery. Multimeter had stopped working so unable to do much testing. Perhaps when the leisure battery is connected the lights and fridge won't pull from the starter. Kind of learning as I go along. Thanks again.

[g8dhe]

If its remained on for 3 hours then yes that is not expected !

Checking out the relay its not really intended for Campervan use its more a Caravan type setup, which has different characteristics, its only just about adequate at a stretch and if the LB has ever been allowed to get low then there is a good chance of its relay not being able to handle the charging current for a LB situated at the front of the vehicle as opposed to LB mounted in a caravan some 4-5 m away behind the vehicle!

I would suggest you pull the Charging fuse close to the SB for the time being until you get the other things sorted and a working multi-meter, as otherwise it sounds like you may well flatten the SB.

[Chief Brody]

Another very useful reply. I'm getting use off a working multimeter today so will get done testing done. Will also reconnect the leisure battery. I know from a search here that some others have these relay units in their bongos. Perhaps not the best choice though. I do know that the leisure battery definitely receives a charge from the alternator when driving. I also know that the leisure battery runs the lights and fridge when the starter battery is disconnected. All very confusing. I have attached some pictures of the relay unit. Not sure why the red core of the black cable is cut going into the relay unit and The black core is cut coming out of the relay. Thanks again.