Intermittent Starting Problem

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Bongo Beagle
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Intermittent Starting Problem

Post by Bongo Beagle » Sun Dec 11, 2016 10:35 pm

Our 1995 2.5TD has developed a starting problem over the past year or so and like all the best tech problems, it is intermittent so hard to reproduce when you need to although he did it right on cue today.

He starts fine when you first go to him and runs beautifully but after driving for even 15-20 minutes and stopping for 5 minutes or so, when I go to start him again it is as if there's not enough power in the battery - tries to turn over but then stops trying after a couple of seconds. Most of the time if I leave it for another 4-5 minutes and try again he will, sometimes reluctantly, start OK. All the correct warning lights come on but dim a bit as it tries to crank the engine and it has just been for its service and the mechanic said the battery is fine (95AH rated) and its charging OK.

I can't figure it out so any advice is very welcome!
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Re: Intermittent Starting Problem

Post by Bongolia » Sun Dec 11, 2016 11:15 pm

Did your mechanic try and find out the cause?
Can you put up a video of the problem?
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Re: Intermittent Starting Problem

Post by g8dhe » Sun Dec 11, 2016 11:37 pm

If the lights dim whilst cranking over it normally points to a voltage drop on the battery. If the battery has been tested itself as OK, then next most likely cause is loose terminals, followed by poor earth connection to the chassis on the -ve battery lead. Disconnect both terminals clean them up and reconnect tightly and see if that improves things.
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Re: Intermittent Starting Problem

Post by teenmal » Mon Dec 12, 2016 11:11 am

Bongo Beagle wrote:Our 1995 2.5TD has developed a starting problem over the past year or so and like all the best tech problems, it is intermittent so hard to reproduce when you need to although he did it right on cue today.

He starts fine when you first go to him and runs beautifully but after driving for even 15-20 minutes and stopping for 5 minutes or so, when I go to start him again it is as if there's not enough power in the battery - tries to turn over but then stops trying after a couple of seconds. Most of the time if I leave it for another 4-5 minutes and try again he will, sometimes reluctantly, start OK. All the correct warning lights come on but dim a bit as it tries to crank the engine and it has just been for its service and the mechanic said the battery is fine (95AH rated) and its charging OK.

I can't figure it out so any advice is very welcome!

Did the Mechanic clean the Battery Terminals ?? and check the starter connections.
Bongo Beagle
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Re: Intermittent Starting Problem

Post by Bongo Beagle » Mon Dec 12, 2016 11:27 am

Thanks for the quick replies.

My mechanic checked out as much of the electrical system as he could and the starter - he said all the connections were good, but I'm not sure if he'll have cleaned and tightened the battery and earth connections, so I'll give those a try. Just been out to try it and he started first time - a little reluctantly, but still a good start compared to trying to crank and then just dying.
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Re: Intermittent Starting Problem

Post by teenmal » Mon Dec 12, 2016 1:06 pm

Bongo Beagle wrote:Thanks for the quick replies.

My mechanic checked out as much of the electrical system as he could and the starter - he said all the connections were good, but I'm not sure if he'll have cleaned and tightened the battery and earth connections, so I'll give those a try. Just been out to try it and he started first time - a little reluctantly, but still a good start compared to trying to crank and then just dying.

I would be Very surprised if your Mechanic did not carry out this Bread and Butter routine maintenance, especially with the problems reported.

Another starting problem ( not saying that it IS yours) with these vehicles is worn out Starter Contacts.
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Re: Intermittent Starting Problem

Post by mikeonb4c » Mon Dec 12, 2016 3:43 pm

A healthy diesel Bongo should spring to life at the first touch of the key, whether cold or hot. Something doesn't sound quite right to me :roll:
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Re: Intermittent Starting Problem

Post by Bongolia » Mon Dec 12, 2016 4:06 pm

It could well be electrical but there is a possibility its mechanical.
What I find interesting is the difficulty in starting when hot.
Difficult to put this but when its hot is it as though the engine is stuck solid, like "donk donk" or cranking a couple of revolutions very slowly before spinning and firing up?
Do you get any clicking from the starter when you have the problem?
Was your mechanic able to replicate the fault, did he experience the problem?
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Re: Intermittent Starting Problem

Post by Bongo Beagle » Mon Dec 12, 2016 11:43 pm

I agree, the hot start being a problem really doesn't seem right. Earlier in the year I had driven for about 3.5 hours with one stop about half way and starting up was slightly slow, but not too bad. I then stopped for fuel and that's when there was total refusal to start - just as if that battery was almost flat. Some lads kindly pushed me away from the pump so I could figure out what to do next and after about ten minutes of thinking I gave it another try and he started no problem.

To answer Bongolia's question, it doesn't sound like the engine is stuck, more just like its trying to crank but as if their just isn't enough life in the battery to actually fire up. When it does fire up, it is the couple of slow revs before catching. No clicking from the starter motor and I think he experienced a couple of reluctant starts but not complete refusal.
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Re: Intermittent Starting Problem

Post by Bongolia » Tue Dec 13, 2016 12:52 am

Without hearing this it is difficult to say but I am wondering if you have the start of a head gasket failure. :(

Basically when the engine is hot the water leaks into a cylinder.
When you try to turn the engine over it is trying to compress the coolant that has entered the cylinder. This wont compress and so the starter seem reluctant to spin the engine over until it has squeezed out some liquid, this depends on the stroke that the affected cylinder has stopped on, after this it may crank and fire and once that happens it will manage to burn off/ deal with any liquid that enters the bores.
It is called hydrostatic lock or hydrolocking.

I could be completely wrong and it could just be a starter motor/connection problem.
My advice would be to make your mechanic aware that this could be an issue and ask if he would carry out a block test.
This uses a chemical that will change colour if combustion gases are present in the coolant, so it has to be carried out when the coolant is hot and after being driven for a while.
Have you experienced any loss of coolant?
You didn't mention if your mechanic was able to reproduce the problem or not.
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Re: Intermittent Starting Problem

Post by Bongo Beagle » Tue Dec 13, 2016 10:53 pm

I certainly hope we're not in head gasket territory, but I'll give my mechanic a call and run that past him. There's certainly no loss of coolant.

I don't think he was able to reproduce the problem at its worst - he had some sluggish starts, but not a total refusal. I tried it this evening (not been run for two days) and it started immediately with no hesitation three times in fairly quick succession.
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Re: Intermittent Starting Problem

Post by Bongolia » Tue Dec 13, 2016 11:47 pm

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wonkanoby
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Re: Intermittent Starting Problem

Post by wonkanoby » Wed Dec 14, 2016 5:56 am

get the contacts and plunger on starter changed

http://www.ebay.co.uk/itm/MAZDA-BONGO-2 ... aLg6A8kzew
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Re: Intermittent Starting Problem

Post by Bongolia » Wed Dec 14, 2016 9:40 am

Just a further thought. If you have or can borrow some jump leads, when this happens take a lead attach to neg terminal of the starter battery and clip the other end onto anything solid on the engine or gearbox then try it. That would eliminate any dodgy earthing problems.
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Re: Intermittent Starting Problem

Post by windywatson » Wed Dec 14, 2016 2:31 pm

Hi,
This strikes me that its an electrical fault when hot. I had a car that would eventually die on me as it got warmed up. let it cool down and off we went ok again until hot. Turned out to be the HT coil, Failing whilst hot & causing loss of spark. New coil end of problem. I wonder if its passible that the starter solenoid is doing similar. Due to the engine bay having the large cover under it, perhaps the localised heat is enough to be effecting it. Simple test would be to drop the cover off and do a run without. Perhaps that would reduce the heat enough to prove the theory!

cheers
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