24v RV8 Starter Motor

[garrycol]

My RV8 is a 24v unit and the starter has chewed itself and either needs replacement or an expensive rebuild from an electrical winder.

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There are certainly none available in Australia and the only one I have found that is in stock in the UK is over £400 landed here.

So options:
- buy the new starter from the UK
- get my current starter rebuilt - not costed but will be very expensive
- put in a 12v starter "cheap as chips here" and change the starter system to run off my 12v aux battery, but as it is a deep cycle battery I will need to use a hybrid deep cycle/starter battery and run the risk of having no start power when camping after a night or two with fridges and light running off the same battery
- follow a future suggestion from the forum on how to deal with this - anyone know of a seller of cheap 24v RV8 starters?

Also I have read about hi torque stater motors being used by people on here - where would I find one of these? My engine is a bit higher comp and could probably use a higher torque starter.

Any comments/suggestions would be appreciated.

Cheers

Garry

[unstable load]

I'd first do the sums of a new 12V starter, both high torque or not, AND a new battery, versus rewinding your unit.

Hit the truck spares places, they run on mostly 24V and see if there isn't a compatible motor that you can adapt to fit.
Also, Leyland being the parts bin robbers they were, look at the contemporary Leyland trucks of the day, like the Boxer, there may be one in a scrappy waiting to be picked.

[garrycol]

Thanks John - yes at the end it will be a cost vs function equation.

The only "commercial" vehicles we had in Aust with a Leyland V8 was the Terrier which was in fact a 4.4litre leyland V8 - but 12v. I am not sure if anything else would be compatible and dont have the resources or knowledge to research this aspect.

Now I do have a 12v starter here and the armature looks exactly the same as the 24v armature - certainly the wires are the same size and it all looks similar. Maybe it is the size of the windings in the stator that are different and need 24v.

I am tempted to put the 12v armature into the 24v body, put the undamaged 12v bush cap on the end with the 24v solenoid and see what happens - i have nothing to loose.

Cheers

Garry

[Ian Anderson]

Many many moons ago, I used to race formula V
Had a pasta rod engine, original rules were 1100cc then 1200 then 1600
Well in the 1100 large valves and porting done and skilled to raise compression
These were additionally modified and put on the 1600 bores.
Resultant was probably about 14 to 1, but we were in Zimbabwe at 4500 feet altitude to that mitigated it a bit.

Anyway the starter was a 6v unit. But we ran a 12v battery. It worked fine.

So I would certainly try the starter on you 24 volts.

Or
Most 24v systems I have seen are two 12v batteries connected together.
Could you tap into the connection and use only one of the batteries for 12v?

Ian

[ChrisJC]

The 'high torque' starters were those used on vehicles like the Range Rover P38, Disco II. I rather think that the later Range Rover Classic's had them too, probably coinciding with the introduction of the fuel injected models. They have a much smaller body than the older starters.
Note that the position of the solenoid on the starter body is different between the '4x4' application and the 'Car' application.

As Ian says, I would firstly just try a 12V one at 24V.
Then if the armatures are interchangeable, I would try a 12V armature in a 24V body and see what that does.

Finally, could you have an extra 12V alternator and 12V battery just for starting?, or a unit that charges a 12V battery from 24V?

Chris.

[DaveEFI]

I have an after market Hi-Torque unit on my SD1. It uses a smaller permanent magnet motor which runs at a higher speed and a reduction gearbox. The motor itself is Denso. Not sure if that motor comes in 24v. But the motors are common on modern cars, etc. Many of these after market units have a used motor as the basis.

I'm old enough to remember cars with 6v electrics. Things like small Fords of the early 50s. Since they had a chassis, they were popular for 'specials'. And if converting to 12v, most just used the 6v starter. It is the current flow through the starter that heats it up - and it could be a small 24 battery couldn't supply any more current to the starter than a 12v one.

[garrycol]

Hi Ian - thanks for the comments - unfortunately tapping off something like a starter off one battery is a quick result in killing both batteries due the resulting differential charge of batteries. To do that you need an expensive equalizer between the two batteries. But in my case is not needed as I do have a seperate 12v auxiliary system to provide power for my camp fridge and lighting etc.

Chris - as mentioned I do have a separate 12v system - I used to have a second 12v alternator but it was problematic due to where it had to be mounted on the bottom of the engine. I now have a 60 amp 24v to 12v Dc Dc smart charger for this but the aux battery is currently a deep cycle battery which cannot handle starter motor loads so would have to be changed to a hybrid that can handle starting and deep cycle.

So if it is too expensive to stay with 24v for starting I will need to look at 12v options.

I just find it amazing that a new 24v starter is 6 times more expensive than the 12v version.

Dave I here what you say about a generic motor - like a Denso but without some links etc on what fits it is hard to work out what may fit.

Thanks
garry

[DaveEFI]

As regards the after market units like Power Lite, I think they use a stock motor and possibly gearbox, with only the mounting being special for the individual engine - no different from Lucas, really. So if a 24 volt motor was available, it would be no big deal to swap it. But you could ask them if the do a 24 volt one for an RV8 - I get the impression they're a small enough company to help.

At one time, it would have been easy to get burnt out Lucas etc motor fixed. But not sure about now.

[garrycol]

Thanks Dave - I have identified the relevant page on the PowerLite web page and they only list 12v but I have sent them an email asking if they can do a 24v unit.

Cheers

Garry

[garrycol]

This morning I was able to locate a local supplier who has new 24v armatures for a good price (equiv of £50).

As it was the armature and the brush holder that was wrecked, this armature and the spare 12v brush holder should see the problem resolved.

Cheers

Garry

[DaveEFI]

Result.