exjay9

Member
Hi
Since its got cold, my 300tdi auto is "reluctant" to start. The battery is only 6 months old & it and the alternator are ok (I took it back to eurocarparts and they tested it, 100% charged & 99% healthy)
It spins over faster and starts ok with a battery pack connected, so I think it needs either the more powerful battery or dual batteries.
What I would like to know is, if I put a second battery in, could I just connct the negative to the chassis and the positive directly to the existing battery?
I dont have a winch or extra lights, I just want more starting oomph!!
Thanks
Gary
 
A good idea is to install an extra engine earth lead - i connected 1 from the battery to a bolt on the timing cover, it does make a difference!!! ;)
 
I did try a jump lead from the negative to the engine block, but it didnt seem to help, I do think the starter may be a little lazy, I was thinking of changing the brushes, anyone else done that?
 
Before I get onto the twin battery setup lets look at the issues at hand.

Easiest things first, check the battery terminals and connections followed by the cable itself. Check all terminations to the engine, chassis and starter.

The starter motor itself is an easy item to work on. I hate the things and like alternators they are built to use black magic in my opinion lol. However through necessity I have totally stripped the starter and rebuilt it and it is easy. Mine was full of mud and crap.

Connecting a booster pack will make a difference to any motor as it is a powerful 'booster pack' so don't get too distracted. Check all earths.

With regards to a second battery you really don't want it connected when the ignition is off as any current drains will take the charge out if both batteries. Sort of defeats the purpose of a second battery.

For £24 you get a 200amp solenoid from Vehicle Wiring Products which you can switch from the ignition so you get both batteries on start and they both charge but they are separated when you stop the motor. Either use the ignition or use a simple switch on the dashboard.

Hope this helps
 
Just to let you know our 300tdi is a right sluggish starter when it's cold too.

Has been that way ever since and one does not seem to have identified a fault, yet nor has one looked for said fault :D
 
My 300tdi Auto is also a bugger to start in the cold, would love a dual battery set up for when I go up in the mountains in winter, but where to put it is another question.
 
Disco 1 has an identical tray on the passenger side which is used for carrying such pansy items as jack and wheel chock.

Ideal!!
 
Disco 1 has an identical tray on the passenger side which is used for carrying such pansy items as jack and wheel chock.

Ideal!!
Thats where the 2nd battery sat when i had a split charge with dual batteries on my 300tdi disco :) all you need to do is remove the bottle jack and wheel chock and the airbox elbow going to the inner wing :)
 
While we're on this subject, what would people say is the better option when fitting a second battery?
Split charge system or second alternator?

I'm fitting a second battery next year so wondering which option to go for and what the benefits are of whatever is suggested.

Ps, sorry about the :hijacked:


:D
 
Gotta be a search on this mate, I remember writing chapter and verse about it not that long ago!!!
 
A twin battery set up will not help in starting - as I had this problem when I was using Veggie.

In the end I went for the biggest battery possible, a 1000CCA one just fitted - I then used my then current battery and fitted this as a second Aux battery with a split charge system.

Then I fitted a second fuse box, and tried to run as much possible off the 2nd battery - lights, radio etc etc so it kept the main battery from additional drainage, plus have the work lights on without the engine running, knowing I will still be able to start the engine without any issues ;)

I also whacked on quite a few more earth's when I did the wiring, but never bothered about a 2nd Alternator, as have the largest one fitted which seems to do the job.

Now it starts on the button, and if it does go flat, at least I can jump start myself.
 
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Disco 1 has an identical tray on the passenger side which is used for carrying such pansy items as jack and wheel chock.

Ideal!!

Yep, your quite right, just need to check my snorkel (which is still in the box due to me being a lazy git) will not poke forward of the air box, then bingo I'll pop it in there. Mine is an ABS one and it causes a few issues.
 
Yep, your quite right, just need to check my snorkel (which is still in the box due to me being a lazy git) will not poke forward of the air box, then bingo I'll pop it in there. Mine is an ABS one and it causes a few issues.

Have a look at my thread when I made up my snorkel, as I have ABS with the second battery on that tray ;)
 
While we're on this subject, what would people say is the better option when fitting a second battery?
Split charge system or second alternator?

I'm fitting a second battery next year so wondering which option to go for and what the benefits are of whatever is suggested.

Ps, sorry about the :hijacked:


:D
me personally a 2nd alternator is the way to go.
I have an allbright hd split charge and tmax display unit the split charge cant keep up with the demands of the 8274 winch.

in the new year when I can afford it I will be putting a 2nd alternator using the gywn lewis kit and another 100 amp alternator
 
me personally a 2nd alternator is the way to go.
I have an allbright hd split charge and tmax display unit the split charge cant keep up with the demands of the 8274 winch.

in the new year when I can afford it I will be putting a 2nd alternator using the gywn lewis kit and another 100 amp alternator

That answer will ding-dang-doo for me.
Cheers for that, fella. :)

Gotta be a search on this mate, I remember writing chapter and verse about it not that long ago!!!

Although I will be searching for that post, just to gen up on it all. :D
 

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