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Discussion Starter · #1 ·
I now own a JTD GT. The manual says not to clutch start and while looking online for portable jumpstarter packs (as i have had these packs come in handy in other cars I have owned, especially when in the middle of nowhere), I noticed some tend to say "not for use on diesel cars"

What is the deal with both jumpstarting diesels and clutch starts?
 

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diesels need a hefty battery and clutch starts can give a surge to ya electrical system,and can cook ya electronics so no no im my opinion
Interesting. Never did it but never understood why:thumbs:
 

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its all because diesels have much higher compression.

you can try bump starting but you risk just locking the wheels and coming to a very abrupt stop - probably generating many many fault codes in the process.

as for the starter packs - because the little batteries they have in them are not big enough to cope with the diesels which want a higher current.
 

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bump in 3rd and be ready to dip clutch when it fires............had to do this on hols cos wife left ignition and invertor on for tooooooo long........odometer flashed till i stopped the car and restarted it

Gary
 
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I'm with Dave on this one....Modern diesels should never, ever be bump started.... Petrol engines you can get away with but diesels use compression and heat to fire up initially... All you are getting with bumping it is compression only. Unburnt fuel down the CAT, coating the O2 sensors etc... Not good! It only bring on further failures.

Because of the extra current that diesels require to start, surging is an issue when trying to jump start it with cables....
If you don't have a battery charger and need to start the car, disconnect the dead battery terminals first, then connect the jumper cables to it... Give it 10-15 minutes to charge from the other car at 1500+ revs (full charge rate reached by the cars alternator), then disconnect the jumper cables and reconnect the terminals up... Better to be safe than sorry:thumbs:

NB: Always jump with the other car's battery that is equal or of larger Amp/hr rate to your own... or you'll be there for hours!
 

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Discussion Starter · #9 ·
Is there a jump starter pack available for diesels? Here in Austria I am yet to see any decent ones. So as long as the battery is disconnected you can recharge the flat battery I assume by anyway, but never to jump it connected. And never clutch it?
 

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I'm with Dave on this one....Modern diesels should never, ever be bump started.... Petrol engines you can get away with but diesels use compression and heat to fire up initially... All you are getting with bumping it is compression only. Unburnt fuel down the CAT, coating the O2 sensors etc... Not good! It only bring on further failures.

Because of the extra current that diesels require to start, surging is an issue when trying to jump start it with cables....
If you don't have a battery charger and need to start the car, disconnect the dead battery terminals first, then connect the jumper cables to it... Give it 10-15 minutes to charge from the other car at 1500+ revs (full charge rate reached by the cars alternator), then disconnect the jumper cables and reconnect the terminals up... Better to be safe than sorry:thumbs:

NB: Always jump with the other car's battery that is equal or of larger Amp/hr rate to your own... or you'll be there for hours!
I agree, but...

Diesels don't have O2 sensors and if the CAT dies it doesnt matter as it isn't needed (its only there to lower Co2 emissions for tax purposes) so if your really stuck you can try bump starting.
 

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there comes a point when your ecu or ecu will get a voltage spike ........you be posting all sorts of errors problems ,you name it ......and after about 20 odd posts youll mention that you jump started your car or someone elses then be looking for replacement ecu or ecu's............ PLAY SAFE GENTLEMEN!!! charge or replace battery cheapest option in my opinion
 

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Contrary to all the good sensible advice on here I bump started mine a couple of years ago several times when my battery was on the way out, I was going to Jump it but there is a box of electrics on above on of the terminals to the battery. I would always turn the ignition on to let the glow plugs heat up, turn off an repeat a couple of times first to get some heat i there before pushing. Due to the slope on the road I ended up starting in reverse. Worked fine no problems and no error codes!
 

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Contrary to all the good sensible advice on here I bump started mine a couple of years ago several times when my battery was on the way out, I was going to Jump it but there is a box of electrics on above on of the terminals to the battery. I would always turn the ignition on to let the glow plugs heat up, turn off an repeat a couple of times first to get some heat i there before pushing. Due to the slope on the road I ended up starting in reverse. Worked fine no problems and no error codes!
matter of time..................
 

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Discussion Starter · #17 ·
Yeah but even petrol cars say it isn't advised to jumpstart or clutch start them. So is it just some BS brought about by the car companies wanting people to take the cars back to dealers to get raped in price???

Has anyone had personal experience stuffing up an alfas ecu while jumpstarting or clutching it????
 

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Yeah but even petrol cars say it isn't advised to jumpstart or clutch start them. So is it just some BS brought about by the car companies wanting people to take the cars back to dealers to get raped in price???

Has anyone had personal experience stuffing up an alfas ecu while jumpstarting or clutching it????
all modern car manufacturers state that ........most cars now have complex electronics that rely on a stable voltage within parameters.......just look at threads where battery is not healthy and it plays hell with cars electrics........modern cars are designed to start off a KEY or card so dont split hairs please:lol:

a poor connection onto body or battery post can put a voltage spike way above these parameters and yes it will mess everything up :mad: including your wallet and time on here working out wtf wrong with your car.........or even car you have purchased :thumbs:
 

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well shortly after bump starting mine I replaced the battery and have not had any problems (18months later) that could be casued by the bump start or starts as I was bumping it once a day for 2-3 days before getting a battery fitted. Either I was lucky (always a possibility) or the risk is there that you could fry the electrics but is a relativly low risk but with a large bill if it all goes wrong. I agree that modern cars do seem sensitive to battery health and moder diesels particularly so. My dad had a new transit 2.2 a few years back and after only 18months it wouldn't start off the battery if left for more than a day. That also got bumped with no ill effects.
 
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