Difficulty starting in wet/cold

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sibot
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Difficulty starting in wet/cold

Post by sibot » Mon Oct 31, 2016 1:41 pm

Hi,

We've noticed over the last couple of weeks, with the onset of cold/wet weather, that our '95 2.5l diesel Bongo is having trouble starting in the mornings after a few days of not being run. When it fails to start I can hear a bubbling from the coolant header tank, but I'm not sure if this is normal or not since I wouldn't hear it if the engine had caught first time. It's not a constant bubbling, just a couple of gurgles.

The starter battery is the original that came with the Bongo 5 years ago, so I'm wondering if that's on its way out and that's the likely problem but obviously I've read the horror stories about cracked heads causing poor starting by letting water into the cylinders. Would it be worth replacing the battery as a first step, or are there some other things I should do to help isolate the problem?

Thanks,
Simon.
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Re: Difficulty starting in wet/cold

Post by francophile1947 » Mon Oct 31, 2016 4:02 pm

First thing is to check that the glowplugs are working.
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Re: Difficulty starting in wet/cold

Post by g8dhe » Mon Oct 31, 2016 4:07 pm

Check the coolant level, and try to watch it perhaps whilst someone else starts the van, if it is gurgling then you have air in the system, you need to locate where the air is getting in / water out!
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Re: Difficulty starting in wet/cold

Post by Northern Bongolow » Mon Oct 31, 2016 7:15 pm

they do make a gurgling noise when the water pump initially starts, and usually when you turn off the engine it can be heard as the system flow slows to a stop, ive never found it to be air just the noise of the flow.
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Re: Difficulty starting in wet/cold

Post by sibot » Tue Nov 01, 2016 7:45 pm

Thanks - I checked the water level and there isnt any significant loss (I have one of the special edition(!) opaque header tanks so its tricky to gauge an exact level).

Is there an easy way of checking the glow plugs, the 'starting problems' factsheet doesnt appear to be available at the moment. Alternatively i have it booked in for a service next week now anyway, is that something the garage should be able to do at the same time without too much extra effort?
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Re: Difficulty starting in wet/cold

Post by Northern Bongolow » Tue Nov 01, 2016 8:38 pm

you can take off the top bus bar that connects them together and do a resistance test, one lead to the top of the plug and another probe to the head next to the plug and check the reading to the bongo service manual resistance, saves risking breaking em to get them out to test em,
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Re: Difficulty starting in wet/cold

Post by mikeonb4c » Wed Nov 02, 2016 12:08 am

The battery is due for changing anyway so change that. Get a 90Ah one as it'll probably last longer and will better ensure power to gloplugs is maintained when cranking. If tbe problem then goes away you're good to go. If it doesn't then gloplugs have to be next suspect i reckon.

My Bongo doesn't gurgle when switching off - should i be worried :?
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Re: Difficulty starting in wet/cold

Post by teenmal » Wed Nov 02, 2016 10:21 am

First thing is to check that the glowplugs are in fact getting a 11/12 volt feed.

No Feed No Go.
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Re: Difficulty starting in wet/cold

Post by sibot » Wed Nov 02, 2016 10:34 am

Thanks guys, multimeter says I have one potentially working glowplug, which i'm guessing is less than ideal :) so first up is a new set of those.
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Re: Difficulty starting in wet/cold

Post by mikeonb4c » Wed Nov 02, 2016 10:44 am

teenmal wrote:First thing is to check that the glowplugs are in fact getting a 11/12 volt feed.

No Feed No Go.
....ideally when the battery is busy supplying the starter motor, though that might be a bit unrealistic. It is the batteries ability to supply power under load that matters though i reckon, if plugs are not to have their glow quenched by incoming cold fuel mixture
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Re: Difficulty starting in wet/cold

Post by BongoBongo123 » Thu Nov 03, 2016 2:49 pm

I will add I occasionally get a stuttery start and know 1 of the diesel pump seals is probably not sealing as well and letting a bit of air in. It always starts fine though but I am guessing depending on how badly the seal is not meeting it could make starting hard work. Logically I would have thought the colder it is the more the seal will contract in size meaning less and less good seals.

I am no expert Bongo diagnostics person but might be worth bearing in mind at the end as you go through the other suggestions above. Hope you get it sorted and it is an easy fix.

No gurgling when switching off here either.
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