HDJ81 24V to 12V Conversion Underway (1 Viewer)

[SHREDwagon]

Hey All -

Currently ditching the 24V switching solenoid using an IBS relay and a 2.7KW starter. The L/H (PS) battery is now starting and the R/H (DS) is now Aux.

Couple of questions for anyone who has done this conversion:

First pic shows a grey case (interior lights ?) and the black case (labeled starter relay) that were attached to the R/H battery +. Dave2000 connected the interior lights to the Aux +. Does the starter relay (black case) need to connect to either battery?

The second pic shows a ring terminal and a grey plug (signal from turning key to crank position). Both were connected to the solenoid and seem to run to the bottom of the main fuse box. The grey plug is now abondoned, but does the ring terminal need to connect to the L/H battery?

Any help much appreciated!

 

[9180ltd]

Sorry I don't have the answer.... But why? Did multiple components of the system fail making ditching the system a more economical repair?

I love mine, only diesel I have ever drivin that with any more than a flick of the key at any time of the year and your over cranking.

 

[SHREDwagon]

The 24V never let me down. But, the IBS RBM allows me to parallel the batteries for cold starts with 2000 CCA, or whatevers left over from the Espar. Plus, helps shed some weight and I need the room the 31 was taking up in the back.

The more I camperize, the more excess needs to be trimmed. Last week I ditched the cooler console for a Tuffy, and the rear heater for a spot to put my tool rolls. Different priorities!

 

[wildsmith]

Does a HD-T have glow plugs? If so one set of wires on the RH battery might be for the glow plugs - on my FT I'm pretty sure one of those was the intake heater. I left both batteries in parallel when I did my conversion and just put a jumper in the 12/24v relay connector in the LH kick panel. If I were going to make the RH battery into an aux I would connect those wires to the big cable coming from the LH battery then everything is getting power like it used to just from the LH battery.

EDIT: forgot the white (?) wire on the change over solenoid question - that lets the changeover relay in the LH kick panel know when the solenoid has switched to 24v and then it will let the starter relay work.

Why convert? Have you tried fault finding the 24v start? Not rocket science but a bit of an eye opener just how many relays and bits of wiring loom are involved in making that happen. Still starts with barely a flick of the key on 12v

 

[Dougal]

The 24V never let me down. But, the IBS RBM allows me to parallel the batteries for cold starts with 2000 CCA, or whatevers left over from the Espar. Plus, helps shed some weight and I need the room the 31 was taking up in the back.

I don't see the logic there.
You don't need 2000CCA in the cold with 24v.
P = VxA. With no line-loss 24v delivers the same cranking power with half the current.
Account for the line loss (which can get quite big when pushing big currents on 12v) and 24v delivers far more power at half the current. Put simply, 24v is superior starting in all conditions. I would never drop back to 12v in a cold climate.

Worried about the weight of a battery in an 80?

 

[Douglas S]

I'm so tempted to do this...adding a third battery is a bit of a PITA. I worry about starting ability at -40.

 

[SHREDwagon]

Thanks Wildsmith - You've answered my question. Both of the stock connectors on the R/H battery need to be connected (interior lights and glow relay). Both of the stock connectors on the L/H battery leading to the solenoid are left unconnected.

Dougal - You're right. But, I'd need to add 2 batteries. Guess it depends on priorities. So, ability to self jump with 1 aux battery, space and avoiding alot of extra wiring/complications. Few guys running 12V set-up in Germany on both HD's and HZ's, with no issues in cold (-20C). Cables from Aux to Main, and main to starter are 2/0. I would not recommend doing this without an Espar/Webasto (for backcountry) or block heater, quality batteries and the ability to parallel aux & main. Oh, and a higher amp alternator!

Douglas S- Is 24V start the most important part of the equation? Or a good block heater and fuel additive?

 

[markthemenace]

My bone stock until I upgraded by battery cables for the positive 24v HJ60 with 2H.

This is the strongest and fastest starting vehicle I've ever owned. I am constantly amazed by how quickly it fires up, with such gusto that if an unsuspecting pedestrian were to be walking by the cruiser when I start it, they invariable get startled and jump!

I did have one glitch though, and could not believe it when my wife claimed that the car sometimes starts really slowly! I happened to be standing by it once when it happened.

Checked the bAtteries, they were holding good voltage (they were 2nd hand Mopar units from a Dodge truck that couldn't start). Couldn't have been my new cables. Wait a minute...what's that arcing sound? Holy smokes the GROUND was crap! There was a burn mark on the hood protector too!

Well I used the old positive cable (never throw anything away) and put new copper ends on it and made one solid connection back to the alternator ground.

She's been starting sweetly ever since.

I like th 24v system so much that I converted my headlights to 24v too! I think it's a great system and just like 240v ac....what's not to like?

 

[100 TD]

IIRC the 24v starter was a 4.5kW for cold spec countries. The 1HD-FTE comes out with a 3kW 12v starter, and the 1HZ comes out with a 2.5kW starter. So if you are converting and want the best available, go for the OEM 3kW unit. 2.5kW may do just as well though. The best thing you can do is upgrade the starting and ground cables to 0 or 00 to alleviate voltage drop.
The 1HD-FTE comes with 2 batteries in parallel, but as many have done, I split mine and start off one, I use the other for my fridge and/or jump start if need be. Currently using 2 x CAT 175-4370 batteries, 825 CCA
OEM denso alternators are 120 amp as well on the 1HD-FTE and some 1HZ

 

[SHREDwagon]

Update with pics

Thought I'd update this thread for anyone venturing down the same path.

Firstly, the 2LT 2.7kw starter has the stud on the wrong side. It works, just not ideal and makes install/removal more of a chore. If your going to do this, might want to pony up the extra $100 and get the proper one from Oz.

I ran all new 2/0 cables from starter to main +, altenator to main +, engine ground to main -, main + to IBS, IBS to aux + and engine ground to aux -. Overkill I know, but the welding cable was free. Both batteries are grounded to either side of the engine.

The grey & black cases in the first pic above attach to Aux +. For the two wires in the second pic above, I cut the grey connector off and joined the green wire to the white wire with a waterproof butt connector. Read the FSM for more info on what does what. I'm no Sparky, so won't go into the install details. In this configuration, everything except the starter and headlights runs off the group 31 aux battery, like it was planned!

I ordered all connectors from Del City, cheaper and no Chinese crap. Coal Hersee is made in Mexico - but at least North American! Make sure you have a hammer-crimp connector, lots of waterproof heat shrink and terminal lugs.

I also wired up my compressor and ran power to the rear Wiredwagon Bussman relay/fuse box. Both off quality circuit breakers: 150A for rear power and 80A for the Extremeaire compressor. Also used 2 bulkhead power studs in the rear to feed the Bussman.

Total cost with 2.7KW starter, custom brackets, the soon to be installed Mean Green 200 amp alt, IBS relay and booster module - with free cable - was around $1k. Does not include new batteries. Lots of ways to save though. Like Princess Auto for instance.

IMHO 24V start is of no use on a wheeling/camping rig. To each there own!

 

[SHREDwagon]

More pics & video

Made a video starting here:
http://youtu.be/tF1Qzz9RBLg
Same as 24V!

Group 31 was a tight fit and needed longer j-hooks and hold-down bracket. Battery monitor allows paralleling at the touch of a button for those cold days or if a battery dies.

 

[canucksafari]

I wouldn't feel comfortable with the proximity of that aluminum battery hold-down strap two the two terminals. At the very least, I would wrap it in electrical tape or a bicycle tube.

Otherwise, it looks very neatly done.

 

[SHREDwagon]

Thanks John -

It's actually a 1/4" clearance. Good point though - I'll cut out 2 semi-circles in the aluminum

 

[canucksafari]

Cutting a hole to increase the gap will help protect the strap from contacting the terminal. However, I'd still wrap the aluminum strap with an insulator. I've now toasted two batteries by having a tool accidentally contact a grounded strap and a hot terminal. I now have no doubts about the welding capabilities of a 12V battery.

 

[Enigma]

Looks good. Glad to hear you have it starting now. I forgot to have a look at mine and send you some pics. Can't really see or tell where anything goes anyways.

 

[SHREDwagon]

Thanks Jeff - My GF bought me a label maker and some clear heat shrink. I nerded-out and labeled everything. Which I hope will make troubleshooting easier a year from now.

 

[Dave 2000]

OK shred, sorry mate, I had hoped you got enough info when you last PM'd me. After my last email to you I spent sometime in the local hospital and pretty rough to say the least. Only now getting my head together and responding to the various email backlog, glad to see you got it all sorted. Nice install but as soon as I saw the aluminium bracket and the terminals clearance I was going to post up but I see Canuck is on the ball.

I was unsure how you were referring to the batteries left and right etc. The battery nearest the starter would be referred to as the left or MAIN battery, I use that as the primary starting battery as it is so close to the starter and the cable run is shorter. Just to clarify EVERYTHING is wired to the AUX battery except the starter main cable, I use the Blue Seas dual sense (charges both ways) relay and leave the switch in the centre position i.e. fully automatic so the system is fit and forget, in the event that anything electrical (parasitic drag, clock/alarm etc.) is drawing too much the starter battery is always protected.

I have parked the cruiser up whilst I find the time to pull out the gearbox and find out why it is making so much noise, it has been parked since January, last week I had to move the car and I pressed the alarm button to turn off the alarm and the central locking barely opened the doors after standing five months. Got in and cranked the engine and it fired and run first turn of the key, exactly as expected. Fair to say that even the starter battery would have been a little low having stood for so long but she still cranked over and started ok, once the engine is running the relay prioritises the MAIN battery and after a few minutes in clicks the AUX

I agree the 24v system is superior in conjunction with the 4.5 kw starter for starting, that has never been in dispute but herein lies the problem. As the two batteries are in parallel when the engine is off (standard on the 80) it will mean if one battery develops a fault it WILL drag down the second battery leaving you stranded, for me not an option keeping in mind I often travel in the middle of nowhere.

Added proof of the ability of a bad battery to kill a good one, is the fact I have witnessed the amount of times I have tried jump starting a vehicle with a faulty battery, the engine will often fail to crank fast enough (often if at all) to start, disconnect the bad battery and crank using just the cables from the donor battery and away you go.

For me the only disadvantage at the moment is the amount of power I use when out camping, I could do with a bigger aux battery but hey if the solar panel keeps up with the demand of the fridge/dvd/phone/shower/lighting then fine I will keep it as is. Unless I have to travel in seriously cold countries I will not change the present system however, if I did revert to the 24v I would fit an isolating relay so the two batteries were separated when switched off, at least you would have something in the event one battery went bad, btw I have tried on a friend LC to spin the 24v starter on just one 12v battery......nothing doing.

regards

Dave

 

[wildsmith]

On mine I run a 3rd battery in a box that fits between the fridge slide and the back seats, bolted to the drawer top, just for the fridge. I fit it when I put the fridge slide in and take it out again when the fridge slide comes out so they are only fitted for a few months each year usually. Everything else camp related runs off the aux battery up front.

 

[Dave 2000]

So you have changed to a 12v starter Jon?

regards

Dave

 

[wildsmith]

So you have changed to a 12v starter Jon?

Yes, 24 volt as configured on the 80 is less reliable than 12v imo, batteries fight each other and leave you with the headache of two jump sources not to mention the added complexity to achieve it. Much easier to keep a single battery in good enough condition and much simpler to jump if the need arises.