Starting issue -Diesel

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helen&tony
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Starting issue -Diesel

Post by helen&tony » Wed Aug 14, 2019 10:55 am

Hi
Still having starting issues with my 2.5 Diesel...plugs replaced, all vacuum solenoids, no shorting at busbar , cleaned all the fuses, battery fine, relay seems O.K, but the solenoids, whilst they click, do not pull the throttle open, and the engine turns over like a cement mixer until starting...
If, out of interest, the engine hasn't started for a day or two, thus there is no vacuum, how does the throttle open then?
Cheers
Helen
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Re: Starting issue -Diesel

Post by mikeonb4c » Thu Aug 15, 2019 10:47 am

helen&tony wrote:
Wed Aug 14, 2019 10:55 am
Hi
Still having starting issues with my 2.5 Diesel...plugs replaced, all vacuum solenoids, no shorting at busbar , cleaned all the fuses, battery fine, relay seems O.K, but the solenoids, whilst they click, do not pull the throttle open, and the engine turns over like a cement mixer until starting...
If, out of interest, the engine hasn't started for a day or two, thus there is no vacuum, how does the throttle open then?
Cheers
Helen
I thought the 'vacuum' solenoid just raised tickover while engine cold? My tickover one doesnt work but Bongo still starts perfectly. Could it be the fuel pump have a dodgy seal and be pulling in air?
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Re: Starting issue -Diesel

Post by helen&tony » Fri Aug 16, 2019 3:44 am

Hi Mike
Definitely a loss of vacuum...The solenoids switch the vacuum unit to pull the throttle open while starting, and it drops off when it fires, and keeps the tickover up until warm. It doesn't sound like the fuel pump....mind you, I'm replacing it anyway in a month or two...they aren't everlasting, and I did the side seals a year or two back...I'll replace a few bits before next year, as I have a trip across the EU next year...hoping that this nonsensical Brexit thing doesn't stop the natural movement of UK citizens....or I'll have to feel the embarrassment of showing a UK passport....and I don't want the added issue of being stranded in an old vehicle. It has also been warm overnight, and around 26 C , and I believe that the ECU stops the solenoids over a certain temperature....not sure on that?
Cheers,
Helen
In the beginning there was nothing , then God said "Let there be Light".....There was still nothing , but ,by crikey, you could see it better.
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Re: Starting issue -Diesel

Post by helen&tony » Fri Aug 16, 2019 6:59 am

Hi
Yup...probably not the pump...just popped out first thing, pulled the vacuum operated cable open a bit , as the solenoids didn't work it, and it fired on the button!...so it's definitely somewhere in the vac. circuit...not the solenoids, as they are new (second hand via Bongospares)...
Puzzle?
Cheers
Helen
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Re: Starting issue -Diesel

Post by teenmal » Fri Aug 16, 2019 9:01 am

mikeonb4c wrote:
Thu Aug 15, 2019 10:47 am
helen&tony wrote:
Wed Aug 14, 2019 10:55 am
Hi
Still having starting issues with my 2.5 Diesel...plugs replaced, all vacuum solenoids, no shorting at busbar , cleaned all the fuses, battery fine, relay seems O.K, but the solenoids, whilst they click, do not pull the throttle open, and the engine turns over like a cement mixer until starting...
If, out of interest, the engine hasn't started for a day or two, thus there is no vacuum, how does the throttle open then?
Cheers
Helen
I thought the 'vacuum' solenoid just raised tickover while engine cold? My tickover one doesnt work but Bongo still starts perfectly. Could it be the fuel pump have a dodgy seal and be pulling in air?



Yes, you have hit the nail on the head, Michael, it is simply a Fast Idle Control Device used to give extra RMP on cold start and when engaging AC pump. Helen, maybe the fact that the overnight temp is 26c this could have an effect on the ECU preventing the throttle FICD operating. I am sure with all the gadgets and gauges that you have you should be able to check the vacuum. :D
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Re: Starting issue -Diesel

Post by helen&tony » Fri Aug 16, 2019 9:54 am

Hi
Teenmal...It's not just the throttle it pulls by vacuum....There are 2 items it opens...I have an inkling that it's a mixture device, also...and ,no, I just checked the temperature as to whether it affects it, as I wondered if there was an involvement with the ECU stopping the opening in high temperatures....I think that's only when the coolant is up to operating temp. as I don't know any external air temperature sensor
Yes...the gauges are handy...but they were fitted when Steve and I were working out "what does which and when, or which does what and when" in the cooling system all those years back...LOL...
I checked the thoughts by turning on the ignition this morning...no action on the throttle....turned the ignition off, pulled the lower cable by hand, foot on the throttle a bit, turned the ignition, twisted the key to start , and it fired on the button....ran it a bit, and turned off. Then I tried the ignition only without starting several times until the 2 cables stopped actuating, each time it got less of a pull on the cables until it got to no pull. This kind of proves that there is a co-relation showing loss of vacuum. I guess that normally there is a bit of vacuum stored somehow over a period to allow the throttle cables to work. OR....conversely, if there is a long delay without using the Bongo, perhaps they only open AFTER turning over for a moment with a pull via the combination of the vacuum pump and a bit of assist from the tubing that goes via the induction pipe round the back of the head...The pipe has that little 2-way valve. There are 2 possible culprits for the vacuum loss at the moment...the 2-way valve, and a blanking plug on thee main feed from the vacuum pump at the front of the engine, but I can't feel or see the little bugger at the moment, as I have a case of the quartermaster's dim eyes at the moment ...Other than those 2 culprits , I'm at a loss for ideas on the vacuum thing?
Cheers
Helen
In the beginning there was nothing , then God said "Let there be Light".....There was still nothing , but ,by crikey, you could see it better.
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Re: Starting issue -Diesel

Post by helen&tony » Fri Aug 16, 2019 10:14 am

Hi
Post-script....I MAY have found the issue...not sure yet.....BUT I just started the Bongo again...this time no movement of the 2 cables on turning on the ignition....BUT a quick spin, and the lower cable pulled without operating the throttle (upper cable), so the instant vacuum from the pump / induction must have enough pull to do what's needed on a moderately warm engine....I'll report back on how the situation unfolds next time I use the Bongo....(I keep car journeys to a minimum)
Cheers
Helen
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Re: Starting issue -Diesel

Post by mikeonb4c » Fri Aug 16, 2019 10:51 am

helen&tony wrote:
Fri Aug 16, 2019 6:59 am
Hi
Yup...probably not the pump...just popped out first thing, pulled the vacuum operated cable open a bit , as the solenoids didn't work it, and it fired on the button!...so it's definitely somewhere in the vac. circuit...not the solenoids, as they are new (second hand via Bongospares)...
Puzzle?
Cheers
Helen
Very strange mine is starting fine even though the raised tickover function is kaput. But I'm no mechanic so better leave it to them to comment. Could use teenmal at this point if he's about.
I Bongo, therefore I am...
Bongoing, BonGoing, BonGone
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Re: Starting issue -Diesel

Post by helen&tony » Fri Aug 16, 2019 1:22 pm

Hi Mike
The raised tickover on mine hadn't worked for years, and there are the 2 cables...one doesn't get signaled by the vac component of the solenoid with the white plug......it's a second solenoid that operates the startup...and the whole system on mine runs perfectly when started...just one little niggle....as I said...watch this space!
Cheers
Helen
In the beginning there was nothing , then God said "Let there be Light".....There was still nothing , but ,by crikey, you could see it better.
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