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Dave 2000
01-03-2010, 12:52 PM
Hi all, this question is mainly aimed at diesel owners but others may have input so feel free. I am looking to purchase and prepare an 80 for expedition use. As 80s tend to be like hens teeth here in Spain and those that can be found are either beaten up or silly money I plan to purchase a VX manual diesel in the UK and this is where I need a little help.

I need an extra battery to run a fridge and other odds and ends and would like to keep it under the bonnet to save space, no problem I hear you say except many markets (including the UK) are 24v starting and 12v running, and this means the space normally used for the aux battery is used up. My plan was to dump the 24v starter and fit a 12v version. Investigations show that some markets got the 24v system and some the 12v set up, its also possible the 24v versions were for very cold climates and yet I have seen 24v starters used on a Spanish version and on a variant from Germany, add to this that Australia also got a 12v version and yet they have cold weather as well and you can see the point of my post.

I will use the information to see if I can dump the 24v system, get rid of the relay changeover system and use the space for my fridge battery.

I would like forum members with diesels to take the time and let me know:

1, The country/area you live in:

2, Original or JDM:

3, 12v or 24v system:

4, The coldest weather experienced:

5, Any cold weather starting problems:

6, Any starter contact issues:

Many thanks in advance, please note I have asked this question on one or two other forums to get feedback from as many countries/environments as possible.

Regards

Dave

waggoner5
01-03-2010, 02:29 PM
1987 VX HJ61 12HT
24 volt start and run
0 problems at 8000k ft and very cold temps usage
Have an Extra 12 Volt battery in the back on a converter/charger to take care of 12V items.

Dave 2000
01-03-2010, 03:07 PM
1987 VX HJ61 12HT
24 volt start and run
0 problems at 8000k ft and very cold temps usage
Have an Extra 12 Volt battery in the back on a converter/charger to take care of 12V items.

Hi and thanks for the reply, I note you are in 'Golden Co' which is where? Was the car an original diesel or Japanese domestic market diesel?

Thanks again

regards

Dave

subzali
01-03-2010, 07:48 PM
Hi, I don't have a diesel and not much knowledge of diesels, but for a question like this I would probably first try this website/forum:
http://forum.ih8mud.com/diesel-tech-24-volts-systems/

there are many knowledgeable people on this forum with Canadian, Australian and other diesels. Some have seen them converted from 12V to 24V and vice-versa for various reasons and could probably offer better input for your predicament than most of us on this forum who have only seen gasoline versions of Toyota trucks (with a couple of exceptions).

And to answer your question from earlier, most of the members/users of this forum are in the general Denver, Colorado, USA area. Golden, CO is a town just west of Denver, among the foothills.

wesintl
01-03-2010, 08:24 PM
12v bj70 canadian, (dual batteries)

I've started it without problems down to -20F

cold weather starting will have more to do with the condition of the engine, batteries, starter.

I think it's going to be more of a PITA to remove the 24 system than deal with the accessories.

Dave 2000
01-04-2010, 10:44 AM
Thanks for the input thus far guys. I just have a thing about expedition vehicles having less to go wrong and by getting rid of the 24v system would be a good start.

Many thanks and keep it coming!
regards

Dave

waggoner5
01-04-2010, 10:53 AM
Hi and thanks for the reply, I note you are in 'Golden Co' which is where? Was the car an original diesel or Japanese domestic market diesel?

Thanks again

regards

Dave

Golden is west of Denver at about 6k ft. The truck is JDM.

wesintl
01-04-2010, 10:59 AM
how cold do you anticipate having to start at? 12v will start a vehicle. There are also webasto heaters to keep things warm if you really think you'll need it. what engine do you plan on doing this to? also, I thought hdj81's use 24v to start and all accessories are 12v. people have used these things expedition style for a long time and I still question the need to remove 24v starting? IMHO less to go wrong is someone meddling with the system vs just running your fridge as a standard 12v accessory. I find it hard to believe all the euro exp 80's with 24v start pull this or do they? what do they say on bushtaxi?

Dave 2000
01-04-2010, 11:33 AM
how cold do you anticipate having to start at? 12v will start a vehicle. There are also webasto heaters to keep things warm if you really think you'll need it. what engine do you plan on doing this to? also, I thought hdj81's use 24v to start and all accessories are 12v. people have used these things expedition style for a long time and I still question the need to remove 24v starting? IMHO less to go wrong is someone meddling with the system vs just running your fridge as a standard 12v accessory. I find it hard to believe all the euro exp 80's with 24v start pull this or do they? what do they say on bushtaxi?

Hi and thanks for the reply. First let em assure you I am not 'meddling', I am a qualified mechanic/vehicle electrician of some 35 years experience. Add to this I have modified many vehicles for off road use (mainly challenge events) along with street/strip cars. I have also served some time working as a commercial fitter so I do not 'meddle'.

Both early 12 valve and the later 24 valve diesels come with 12 or 24 volt starter systems, the 'running' components lights/radio ect are 12v.

The issue is one of 'less is more' when it comes to expedition use however, I enjoy peace and solitude and prefer to be as self sufficient as possible. I now know from the posts so far that 24 volt starters burn out the contacts, this is rare on 12v systems. I also know that the 24v systems appear to have only been used where there is a likelyhood of conditions of severe cold weather except Japanese domestic imports as all the diesels are 24v starters. The fridge will not be the only thing I will be running, I was using that as an example so may have an inverter ect but this is not the point. I was looking to put in a 12v starter and dump the wiring and relays ect that go with it. I can then use the space to fit an aux battery without using up other valuable room under the bonnet.

Also in the event that one battery fails on a 24v system it tends to drag the other down with it leaving you in a non starter situation, care to ask me how I know this? I am just trying to reduce the possiblities of being stranded somewhere, one poster is actually fitting FOUR batteries because he wants the two systems to be separate from each other and with an element of redundancy. FWIW the information coming back so far indicates a positive chance of using a 12v system throughout but of course I will not get carried away just yet.

Thanks for your thoughts, keep them coming

regards

Dave

PS. trying to find 'bush taxi', I can find references but not a forum can you help? TIA

wesintl
01-04-2010, 12:08 PM
http://www.buschtaxi.de/104.0.html

most configurations came in a 12 or 24v config so finding a 12v starter would probably not be all that hard in todays internet world. I'd just buy the rig you want and let the mods begin. It doesn't seem that hard but I guess you want someone that has BTDT?

fwiw my 12v jetta tdi (mexican, not german) with glow plugs (not screen) has started in -20F took 2 glow cycles, no block heater.

Dave 2000
01-04-2010, 02:12 PM
Thanks for the link! You are right sourcing a 12v unit should not be an issue, I am getting reports of some quite cold weather (-15) with standard 12v starting systems and they have no issues either with the contacts burning out. I do not plan on using a block heater but will be using a fuel heater just prior to the one already in the filter head which is standard on all models of the diesel AFAIK?

Thanks again for your help,

regards

Dave

Rzeppa
01-05-2010, 09:59 PM
1, The country/area you live in:


Kittredge CO, USA (about 2330 meters elevation)


2, Original or JDM:

Canadian Mine Truck (non-USA and non-Canadian). HZJ75 w/1HZ, normally aspirated. Very simple engine. No EDIC like the 3B, very easy and reliable engine. I miss my diesel! :(


3, 12v or 24v system: 12V


4, The coldest weather experienced: ~ -20C


5, Any cold weather starting problems:

No, however the starter contacts pitted and caused a problem in an inopportune situation. The motor was stalled while the truck was in a 1.5 meter snowdrift and the starter only clicked but would not turn the engine over. I used the 8274 winch to bump start the rig and get out. Upon returning home to the garage, the starter was disassembled and the problem discovered and corrected with new contacts.

6, Any starter contact issues: Yes, see above. The lower voltage means higher current for a given amount of electrical power delivered to the starter. As a result, as chemistry teaches us, higher current will wear out the solenoid contacts quicker due to metal transfer from the higher current. Generally speaking, the 24 volt system will deliver longer life to the starter contacts, and result in fewer electrical problems related to normal corrosion and age in the connections all across the harness.

The one thing I didn't like about the 1HZ was that the oil filter must be removed (at least within a 70 series engine compartment) in order to access the starter to remove and replace the starter. Other than that, all maintenance and repair issues were very easy on that engine.

Dave 2000
01-06-2010, 12:16 AM
Thanks for that 'Rzeppa', the information I have collected thus far is showing the 12v starter rarely had problems whilst the 24v version did burn it's contacts out. On neither versions was it a regular thing but your comments have been added to my list, many thanks.

regards

Dave

Rzeppa
01-06-2010, 12:53 AM
Thanks for that 'Rzeppa', the information I have collected thus far is showing the 12v starter rarely had problems whilst the 24v version did burn it's contacts out. On neither versions was it a regular thing but your comments have been added to my list, many thanks.

regards

Dave

Hi Dave, I'm Jeff. It was interesting that your query was something I had very-much first hand experience with (burned starter contacts in a diesel Land Cruiser engine), and am happy to share. Given the choice, I would choose a 24 volt system.

I am also an electronics engineer with over 30 years experience designing power supplies, wire harnesses and medical instrumentation, and have found many real-life parallels in my automotive hobby.

My screen name Rzeppa is a play on my last name, Zepp. A fellow named Baron von Rzeppa patented a design for a CV joint in Germany in the 1930s. Toyota licensed (or copied?) the design that the Baron had manufactured at the Birfield Factory, and we have come to know as the "Birfield Joint".

Dave 2000
01-06-2010, 12:57 AM
Hi Dave, I'm Jeff. It was interesting that your query was something I had very-much first hand experience with (burned starter contacts in a diesel Land Cruiser engine), and am happy to share. Given the choice, I would choose a 24 volt system.

I am also an electronics engineer with over 30 years experience designing power supplies, wire harnesses and medical instrumentation, and have found many real-life parallels in my automotive hobby.

My screen name Rzeppa is a play on my last name, Zepp. A fellow named Baron von Rzeppa patented a design for a CV joint in Germany in the 1930s. Toyota licensed (or copied?) the design that the Baron had manufactured at the Birfield Factory, and we have come to know as the "Birfield Joint".

Thanks for that Jeff, I know the joint is a 'CV' but now know why it is called a 'Birfield'.

regards

Dave