Cold Start Problem & Black Smoke

[snowrat]

Hi All
Seeking your advice on a problem I am having with starting my 2.5D Turbo Bongo.
I am living in Chamonix ski resort for the winter and each morning having problems starting my Bongo.

The battery seems powerful enough but some days with the ignition on the engine just won't 'catch'. If I stop and have several attempts on a few days I have drained the battery.

Once started there are clouds of thick black smoke for about 30 seconds but after this has cleared the engine runs well and the worst case is some light grey smoke, possibly due to the cold air.

I have read the posts I can find and it suggests these being the main culprits for the problem...
-High altitude / low oxygen - Chamonix is 1000metres / 3300 ft high
-Extreme cold - overnight temperatures can drop to -30degC and are typically -5/-10
-Mainly short journeys of under 10 miles each
-Some steep hills to climb
-Heavy loads - Sometimes have 6 people

I have recently add some cleaner in the last few tanks and believe the black smoke is due to carbon build up somewhere in the combustion system. I got the problem twice on very cold days in early December just before leaving UK home.

My main questions are...
Do the above reasons for the problem sound feasible?
Could I be causing excessive harm to my Bongo by not attending to the issue?
Anyone ideas/suggestions on how I can attend to the problem?

Any help much appreciated!

[Harry]

Right...first of all you need to get your glowplugs checked...are they all ok?

If they are then when you get into the van turn the ignition on and leave it on sufficiently long to to get the glow plug light to go out. Repeat this a couple of times before trying to turn the engine over.

When the engine has warmed up, leaving the van in 'Park' , give the engine a few bursts of high revs..this will help to remove the crud.

In similar circumstances to yours, in the mornings, I've also put a fan heater under the drivers seat for half an hour before driving.

I used my bongo as a client taxi between UK and Southern France for two years with regular winter trips to the Maritime Alps and Andorra. No probs with altitute bongosickness.

Sadly the van dies 10 days ago after 248,000km

good luck

H

[missfixit70]

I'd check glowplugs first, make sure the relay is working ok, ie voltage is getting to the glowplug rail.
It may be worth blanking the egr & see if that makes a difference with the smoke at all.

[snowrat]

Thanks for the replies. I am just about to check the glow plugs, they could be on their way out or may have some of the deposits of carbon on them. Can you point me in the right direction for checking them?
The glow plug light does go out quite quickly and I have been leaving it about 10 seconds more before trying to start the engine.

Is the EGR the winter warm up system, as I don't have this?
The black smoke is for just a short space of time after starting, but it is each time I start in the morning. Through the day after a morning start it starts first time within a second or so and there is no black smoke.

Sorry to hear about your bongo dying Harry, sounds like you had a lot of use out of it.

[bigdaddycain]

Hi Snowrat, one of the only failings of the glowplug system on the bongo is it's pretty basic, after driving diesels in the past with the bosche "thermostart" system. But, the bongo system is adequate in normal conditions.

Does your bongo have two batteries under the bonnet, and a switch with a picture of an engine on it near your right knee?

If so, click the switch before you start the bongo in the mornings... The switch closes a flap in the exhaust, promoting a quicker warm up of the engine, and i think the "cold start" bongo's have a beefier starter, or alternator..or both!

If the "cold start" facility is in A1 perfect condition then all should be honky dorey, but if the system is getting a bit tired, the flap in the exhaust could jam closed, leading to all kinds of running problems when the engine has warmed!

The EGR system is seperate to the glowplugs.

Under extremely cold conditions, some people like to use an aerosol spray called easy-start, i think it's produced by a company called Bradex. It's like fuel in an aerosol can, when sprayed into the air intake before starting. The engine will actually run on this high octane concoction for quite a few seconds even if the fuel tank is completely empty, but some mechanics warn against regular use of the stuff, as engines can become "addicted" to it!

[missfixit70]

Thanks for the replies. I am just about to check the glow plugs, they could be on their way out or may have some of the deposits of carbon on them. Can you point me in the right direction for checking them?
The glow plug light does go out quite quickly and I have been leaving it about 10 seconds more before trying to start the engine.

Is the EGR the winter warm up system, as I don't have this?
The black smoke is for just a short space of time after starting, but it is each time I start in the morning. Through the day after a morning start it starts first time within a second or so and there is no black smoke.

Sorry to hear about your bongo dying Harry, sounds like you had a lot of use out of it.

Try this to test them -

Take off the feed bar and check the resistance of the plugs one by one with an ohmeter. There should be roughly 1 ohm

Instead of leaving it 10 seconds after the glow plug light goes out, turn the key back straight away & give it another 10 seconds. When I was running on a veg oil mix & had trouble starting in the cold, if I left it 10 seconds after the glow plug went out before starting, it didn't want to know, but 2 blasts with the glow plug light & then start it was ok.
If it is the glow plugs get decent ones, cheap ones have failed in less than a year for quite a few people - NGK are supposed to be ok.
Probably worth your while having a browse using the search facility top right, just remember to use "and" between each search word, eg, glowplug and light.

[Harry]

Thats pecisely what I meant in my first reply.

Turn the key without starting...wait until the glowplug light goes out then turn off then on immediatly....do this a couple of times then go straght to start.

H

[dandywarhol]

If you leave the ignition key on for 10 seconds AFTER the light goes out you're asking for problems - because if you don't start the engine within roughly 15 seconds then the glow plug relay cuts off.

If you go through the palavar of switching on/off/on then you're not going to get the cylinders' air as hot as just leaving the key on for 5 seconds after the light goes out.

Anyway - if the plugs are in good nick you shouldn't need to wait til after the light goes out unless its REALLY cold

[bigdaddycain]

If you go through the palavar of switching on/off/on then you're not going to get the cylinders' air as hot as just leaving the key on for 5 seconds after the light goes out.

The on/off scenario worked well for me when i had a lazy plug dandy,it did eventually glow on a subsequent test, but took three times longer than the others to glow as bright as the "good three". The repeated cycles seemed to get the lazy plug to glow enough for a decent start. On a VERY temporary measure of course, the real solution is a new set of plugs.

[dandywarhol]

If you switch on/off then you're allowing the plug to cool momentarily - leaving it on just keeps it glowing longer and heats up the air more - unless there's some clever elektrickery I don't understand

[missfixit70]

I found that by leaving it on after the light went out, made starting more difficult, maybe I was leaving it on a bit too long, didn't get around to checking how long it took to switch off after the light went out.
Ultimately, as you say Dandy, if you're having to frig about with it, the glow plugs probably need replacing

[dandywarhol]

The only reason I know how long is because I fitted a bypass switch which has a bulb in it and it lights when the plugs are on. On a cold day they'll stay on for several minutes (about 4/5 minutes is the most I've seen on light throttle)

[snowrat]

Hi all, thanks again for the help.
I tried the sequence as Harry & MF70 suggested, turning the ignition on and then off when the glow plug light went out, twice and even 3 times. This possibly made a little difference but did not overcome the problem.

The Bongo is a south Island version with no 2nd battery (other than the leisure I have had fitted) and no engine pre-warm button.

I have just returned from the cold outdoors after testing the glow plugs and found one of them not to be working. It was the third one from the front and had deposits resembling oil on it. I tested them all using jump leads directly onto the battery and the other 3 all glowed brightly. The dud one generated no heat at all.

If the battery is fully charged it seems more likely to start. If I don't manage to start it at the first or 2nd attempts then the battery doesn't have enough power to keep trying, the battery is virtually drained and I have to get a jump start. Jump starting has worked each time.

I intend to get a set of four glow plugs and replace them all with NGKs, however a few things I need to check first...
- The glow plug length, is it measured for the total length or from the top nut (not last slim threaded section) to the end of the 'glow', as I get 83mm from nut to end of 'glow' or 99mm from end to end?
- Any ideas on if the deposit on the dud plug would be carbon similar to the same as from the exhaust on the cold start up or could it indeed be oil and a more serious problem to investigate, when they fail do the plugs have a black deposit on them usually?
- How do I check the glow plug relay?

The easy start may be needed too, need to get the plugs sorted before turning my Bongo into a junkie!!!

[dandywarhol]

The deposit will just be partially burnt fuel IMO - worth fitting 4 NGKs - if one's gone now the rest will follow suit. They're only around £8 each from a Factor.

[missfixit70]

May be worth whipping out the battery (or charging in place if you can) & giving it a full charge, I doubt it's ever getting full charge from the alternator unless you're driving for a couple of hours with no ancillaries running. If you're only doing 10 mile journeys (probably with heaters, lights etc?) it's going to cane the poor battery.
Get some new plugs in there, charge the battery fully & see where you go from there. Keep it simple
To check the glow plug relay, see if it you're getting voltage on the glow plug rail. It should be under a plastic cover on the drivers side inner wing behind the starter battery, make sure it isn't getting damp, you should hear it clicking too.