Series / Parallel Solenoid for 12/24 volts (1 Viewer)

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Joined
Jul 10, 2006
Threads
29
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249
Location
Austin,Tx
Hi,
I just purchased as 12HT JDM motor currently wired for 24 Volts. I am going to put this in my 1982 FJ40. I am trying to plan out my wiring components and have decided on the following :

Dual Batteries
24 volt starter
12 volt engine sensors (Temp, fueld shut-off etc).
12 volt alternator
12 volt winch
12 volt jump capability
Solar 12 volt battery equalizer

I want to stay 12 volts (except for start) because I will have high current demands (Lots of lights, Compressors, A/C blower, Winch.
I want the 24 volt start because everything I have read here says it is superior to 12 volt.

I am looking for a single solenoid solution that I can use to wire the batteries for 24 volts to start (series), then switch to 12 volts (parallel) for normal running/charging.

I don't want to use a bunch of individual solenoids because if one ever fails/sticks or does not fire at exactly the right time it could short out the batteries. Ideally, I want to find one relay that has a 2 normally open and 2 normally closed contacts to do the job. I have really searched around in many auto electric catalogs, marine and rv supplies, and MUD (of course!) and come up with nothing. Surely I am not the first to try this?

I tried to see if I could use an OEM solenoid from another vehicle:
I heard rumors that some 80's vintage semi's trucks (lorries?) had a similar setup but I couldn't find anything.
I have heard that the 81's have something like this, but they have a complicated timer setup integrated with them. I don't have a schematic or parts manual to confirm this. Also, I am in the US so it would be difficult to find a used solenoid from this.
I am speculating that Ford diesel pickup trucks use a 24 volt start since the have a dual battery setup, but I can't find any schematics for to confirm this.


The nearest generic device that I have found is an air conditioner contactor w/ 4 contacts, but I am worried that it will fail with the high-current demands of starting.


Any help is appreciated in selecting a solenoid.

- Eric
 
A/C contactors handle some pretty heavy loads on compressor startup...

Otherwise.... there is some 80 motor that came stock just as you describe- 24v start, 12v system. It is out there....
 
So you want a 24v start and 12v everything else.
I would think the best thing to do is have 2 batteries (which you probably want anyways) running in parallel. Then get yourself a series/parallel switch for the 24v starter. They are pretty simple. My HDJ81 with a 1HD-T came from the factory that way. 24v start, 12v everything else. One off a HDJ80/81 would be your best bet. That is what they are made for. You could try www.gscruiserparts.com

They have 4 plugs on it. I think both + leads, a - lead, and the 24v out?
Then there is another plug with 2 connections.
I assumed they were a ground, and the 12v activater signal to engage it (would come of the ingnition).

For all the other 24v sensors, edic, etc... you could probably run them off a solar converter.
I don't think there would be a high amp demand there. Others could say better.

Hope this helps,
Nick

BTW: I would love to see pics of the build.
 
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A/C contactors handle some pretty heavy loads on compressor startup...

Otherwise.... there is some 80 motor that came stock just as you describe- 24v start, 12v system. It is out there....

The problems with contactor are :
They are typically rated for A/C voltages in the 120-600 volt range with no specs for low volt DC.
They do not have large-guage cable clamps on them.

The '80 switch sounds interesting!
 
Nick,
After reading *all* of your diesel posts I suspected you might just reply to my request! :)

Did you use this solenoid switch in your truck? Do you have a picture of it? A part number for the solenoid would be really EXCELLENT!

For expedience, I would prefer to try and get a couple of these down here in the states (one for a spare). Has anyone purchased one of these solenoid state-side?

FYI: I am actually doing TWO diesel conversions: FJ-40 + 12HT/H55 and a LX450(FJ80) + 1HDFT+H150. The '40 is going to get converted first because the Lexus is my daily driver.

Perhaps I would have seen this '80 solenoid when the 1HD arrived, but I have asked to hold off receiving that motor until the '40 is done so my garage is not totally FILLED! ;p

I am posting poser picture of my '40 when I bought it. It is SOA, OME springs, Saginaw P/S, Electric Locker Front, ARB rear with 35" tires.

I will take LOTS of pictures of the conversions as soon as the first engine arrives.

Thanks for your help!,
Eric
IMG_5684 copy.jpg
 
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Hi,
I just purchased as 12HT JDM motor currently wired for 24 Volts. I am going to put this in my 1982 FJ40. I am trying to plan out my wiring components and have decided on the following :

Dual Batteries
24 volt starter
12 volt engine sensors (Temp, fueld shut-off etc).
12 volt alternator
12 volt winch
12 volt jump capability
Solar 12 volt battery equalizer

I want to stay 12 volts (except for start) because I will have high current demands (Lots of lights, Compressors, A/C blower, Winch.
I want the 24 volt start because everything I have read here says it is superior to 12 volt.

I am looking for a single solenoid solution that I can use to wire the batteries for 24 volts to start (series), then switch to 12 volts (parallel) for normal running/charging.

I don't want to use a bunch of individual solenoids because if one ever fails/sticks or does not fire at exactly the right time it could short out the batteries. Ideally, I want to find one relay that has a 2 normally open and 2 normally closed contacts to do the job. I have really searched around in many auto electric catalogs, marine and rv supplies, and MUD (of course!) and come up with nothing. Surely I am not the first to try this?

I tried to see if I could use an OEM solenoid from another vehicle:
I heard rumors that some 80's vintage semi's trucks (lorries?) had a similar setup but I couldn't find anything.
I have heard that the 81's have something like this, but they have a complicated timer setup integrated with them. I don't have a schematic or parts manual to confirm this. Also, I am in the US so it would be difficult to find a used solenoid from this.
I am speculating that Ford diesel pickup trucks use a 24 volt start since the have a dual battery setup, but I can't find any schematics for to confirm this.


The nearest generic device that I have found is an air conditioner contactor w/ 4 contacts, but I am worried that it will fail with the high-current demands of starting.


Any help is appreciated in selecting a solenoid.

- Eric

Your over complicating things with the 24v start and the 12v running.
THe 12HT I had started perfectly with a non functioning glow and a 12v starter.
Both my 1HZ start great with a 3 seconds glow and 12v starter.
All you need is a high amp alternator to keep the battery charged up;)
Of course I dont have to deal with extreme cold where 24v is superior.
But Texas isnt exacly a frozen wasteland either is it:D

Good compression and good pump pressure is more important for easy starting on a diesel.
 
Eric:

There many industrial contactors that have current capacities that are far in excess of what a automotive starter motor will draw - the problem is, all the bigger stuff will be three phase, and are not packaged for an automotive application . Also, you would not want to pay for them just to run an automotive starter.
 
Your over complicating things with the 24v start and the 12v running.
THe 12HT I had started perfectly with a non functioning glow and a 12v starter.
Both my 1HZ start great with a 3 seconds glow and 12v starter.
All you need is a high amp alternator to keep the battery charged up;)
Of course I dont have to deal with extreme cold where 24v is superior.
But Texas isnt exacly a frozen wasteland either is it:D

Good compression and good pump pressure is more important for easy starting on a diesel.
Hi there,
you are correct: Texas is a generally diesel-friendly climate.

However,
I intend to take this vehicle into Canada, Alaska, Colorado, the Sierra Nevada range and other dessert areas where I will experience sustained high altitude, very cold (sub-zero) starting conditions.

My limited experience with non-Toyota diesels (Ford and Mercedes) is that cold starts require good batteries, glow system and high torque for that thick, cold oil :)
I am trying to not get OEM parts rewired for a different voltage. I would really prefer to use all off-the-shelf devices for my buildup.

Are you recommending retrofitting an aftermarket alternator like a GM or rewiring the existing 12HT unit?
As I understand it, the 12HT alternator is intimately connected to the vacuum pump.
Is there a Toyota-spec'd 'high-amperage' alternator with a built-in vacuum pump?


regards,
Eric
 
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.

Are you recommending retrofitting an aftermarket alternator like a GM or rewiring the existing 12HT unit?
As I understand it, the 12HT alternator is intimately connected to the vacuum pump.
Is there a Toyota-spec'd 'high-amperage' alternator with a built-in vacuum pump?


regards,
Eric

As far as I know the 12v 12HT (all aussie diesels are 12V) only comes with 55A alternator and the vac pump attached.
{Im glad Toyota ditched that on later model diesels;))
On the other hand it still seems to do the job in Australia for owners here.
The high amp alternator only helps at recharging,not on start up ,so I suppose the lower amp alt will just take longer to top the batteries up.
An auto electrician told me my 110 amp alternatr on the 1HZ is really only needed for extreme situations when your offroad using a winch and all the lights plus spotlightS reguarly.
However your heading into colder climes and I dont know just how much power you will be using

The 61 series I had ,had a twin battery set up where each battery could be used separately or together but still always 12v.
Its a common set up in oz and the switch is a marine unit that is very reliable
 
There is a series/parrallel relay made by Delco for exactly what you describe.
I ran one on my HJ45 for 20 years.
All I had to do on the engine before installation was change the glow plugs
to the 12v units and install a 12v alternator. I had a manual glow system with a toyota glow plug relay.
24v starting is vastly superior to 12v. spins much faster and you dont need
huge battery cables.

I will try to get you a part number for the relay, I think I even have a used
one floating around somewhere.
 
I had checked a Delco catalogue early on in my quest and did not find the relay.
Perhaps I used a very reduced catalog?...

My thought was to retain the 24-volt glow screens. I plan to use a toggle switch at the dash that activates the 24-volts to warm the screens and then hit the starter. I was told that the screens have two wires to each and I could supply either 12-volts to one side of them and still use them effectively. I **assume*** I can put 24 volts across both leads? Maybe I am better off using 12-volt glow screens? I have no idea what they cost.

The question of a glow-screen timer does come up and what voltage to use.
I suppose I could have another toggle switch to manual operate the glow screens. I would definitely have a bright light/buzzer to warn me that the screens were ON - less I forget in the excitement of starting the engine!:rolleyes:

As far as alternator ratings go, I think the goal is to never drain more power than the alternator provides in the long-term.

Here is my true story/perfect storm situation: driving in a boulder-field in the Panamint Range in the middle of the night trying to find our way in near-freezing, rainy conditions: Low-RPM for crawling, Lights blasting to see obstacles, heater fan at max to keep girlfriend/wife from becoming impatient :eek: , ARB humming away stuffed in the back of the rig.
Finally get to camp and immediately shut down rig so I can set up camp for the night & not piss off everyone with engine noise/exhaust.

Low RPM's = low power output from alternator, continuous big load from blower and lights. No chance for charge recovery. Frost on everything in the morning. I guess I could just rev it for a few minutes to let it recover a little...
 
Delco P/N 119844 or 119844
Not sure what the difference is. Run the numbers in google and you will
find several places that sell them. Used in boats, old Ford and Mack trucks.

If you can change the intake heaters to 12v it will be a real easy installation.

If you need to retain the 24v intake heaters, you would have to install a toggle
switch that would route the start signal (to the 24v starter solenoid) to a relay
for the intake heaters. You would need to hold the key switch in the start position and hit the toggle switch at the same time.
Anything is possible if you are clever enough.

Good Luck!
 
Delco P/N 119844 or 119844
Not sure what the difference is. Run the numbers in google and you will
find several places that sell them. Used in boats, old Ford and Mack trucks.

If you can change the intake heaters to 12v it will be a real easy installation.

If you need to retain the 24v intake heaters, you would have to install a toggle
switch that would route the start signal (to the 24v starter solenoid) to a relay
for the intake heaters. You would need to hold the key switch in the start position and hit the toggle switch at the same time.
Anything is possible if you are clever enough.

Good Luck!
Hi,
is there a typo? You used '119844' for both numbers. Also, I tried acdelco.com, google and several other search engines for that number and came up empty handed.

I was going to put the intake heater switch on the left side of the steering wheel so I could use both hands for starting. I thought it would be easy since the system would already be jumpered for 24v. I would not revert back to 12v until the engine had warmed up a bit.

How long should the heater be on before trying to start?
Should the intake heater only run when air is flowing accross it?
How long does it stay on once the engine is running?
 
<snip>driving in a boulder-field in the Panamint Range in the middle of the night <snip> heater fan at max to keep girlfriend/wife from becoming impatient <snip>

Dude... you're riding around with your Wife AND Girlfriend :eek: ....

no wonder you're so worried about batteries.

or

When do you have time to work on your truck?!?
 
Dude... you're riding around with your Wife AND Girlfriend :eek: ....
no wonder you're so worried about batteries.
or
When do you have time to work on your truck?!?
Actually - that trip was the test-drive vacation to see if the girlfriend was wife material! After 1 week of primitive camping in the Panamint range near Death Valley she proved she was a super-trooper. We are now hapilly married with 1 son and 2 cruisers.... :smokin:

As for time: a non-negotiable wedding precondition was that I be afforded time/space for my 'cruiser pursuits! :bounce: :bounce2:

- Eric
 
Workable solution

Hi,
here is my conclusion.

Several people have PM'd me with the following style solenoid.

The name is "Delco 3-Cap Parallel Switch".

It was originally a Delco part number : 1119844
Haldex used part number : BE51111 (old p/n)
The latest Haldex part number is : RS119000X

The original application is for Mack trucks.

Haldex USA can be reached at : 800-643-2374 in order to find a local retail outlet.
The USD list price is : $262.00 (plus $30 core charge)
I found a 2 local retailer here in Austin that quoted me $189.00 (including core charge).

This unit can also be obtained from Custom Marine Services (CMS) 800-992-7922.
cmsquick.com
I don't have a price from CMS because it is not disclosed on their website and they didn't return my calls! :eek:


For those Toyota purists:
Sheldon at G&S Cruisers has an equivelant Toyota solenoid from a diesel '80.
I'll leave it to him to quote a price.

As soon as I start my conversions, I will start a new thread and post pictures.

- Eric
prod_17_sol602_01_small.jpg
prod_17_491012_00_small.jpg
prod_17_sol602_03_small.jpg
 
I have had a problem with that solenoid on my 80 for years. I'm not the only one. The biggest headache is that it isn't available locally except as a second hand part and truly, once cleaned up, you can't tell a good one from a bad one as they work well initially but usually stop working after a while. Buying them from Japan is also prohibitive as the cost is well beyond us.

The solution we've come up with is to do a direct feed of the starter from the two batteries. Please don't ask me for the wiring. I am totally ignorant. It seems to be an ok solution but I really have to wait to see if problems develop. The most immediate result is that the engine has returned to a one click start.

I was looking for a picture of the part involved, but I seem to have lost it. Sorry.


Kalawang
 
I have had a problem with that solenoid on my 80 for years. I'm not the only one. The biggest headache is that it isn't available locally except as a second hand part and truly, once cleaned up, you can't tell a good one from a bad one as they work well initially but usually stop working after a while. Buying them from Japan is also prohibitive as the cost is well beyond us.

The solution we've come up with is to do a direct feed of the starter from the two batteries. Please don't ask me for the wiring. I am totally ignorant. It seems to be an ok solution but I really have to wait to see if problems develop. The most immediate result is that the engine has returned to a one click start.

I was looking for a picture of the part involved, but I seem to have lost it. Sorry.


Kalawang
I suspect what they do is run a more direct wire to the starter solenoid.
I had this problem on Ford once and an auto electricain put some wiring that would get more power to the starter.
He said the OEM wiring was too long and lost power as the wire got older.
I had the car for another 5 years and no problems
 
Hi, been down the road of trying to install the busy and somewhat complicated 24 volt start switch.

Not worth the effort, in fact we have heard of two going south, I would and have always used the KISS principal.

We are speaking of a low compression turbo engine, takes little to spin it over even in cold conditions.

I was following wires yesterday on my 1hd-t and after about a hour of reading the manual and chasing wires I once more have decided against this on any of my next installs(unless the customer wants it).

Sheldon on this board also uses the 12 volt starter on his 1hd-t.

One of my customers in the Oregon mountains is also using this same 12 volt starter and running bio diesel.


Good luck.


Rob
 

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