View Full Version : 101 24V Ignition Waterproofing
101RRS
20th January 2010, 01:23 PM
I mentioned a waterproofing issue in passing in this thread http://www.aulro.com/afvb/technical-chatter/96279-101-v8-died-3-5l-3.html#post1161482 but it is now a 101 specific issue.
My 24v 101 has supposedly a waterproof ignition system (spark plug leads are now normal leads) and I have had no issues with the shallow water crossings I have done to date. On the weekend I went through 12" of water maybe a little fast :twisted: and my 101 died and has not started again despite plenty of WD40 and 3 days to dry out. I had to have the 101 tilt trayed back home.
On looking at the system I found that the dropper that drops voltage from 24v to 10v for the coil is not water proof at all and indeed has large cooling vents that act as scoops for the water to enter. The shielded cable that runs from the dropper to the coil has been cut and a normal connector put in. The same applies to the LT cable from the coil to the dissy. On taking the dissy cap off - it is inside a cast aluminium cap the dissy cap has a piece missing near the bottom but as it has been working Ok I guess it is not an issue - there was no water inside the actual cap but there may be water between the cap and its outer casing. The same may also apply to the coil - there may be water inside the protective outer casing.
I am yet to pull the coil out to check it and have not as yet separated the dissy cap from the outer casing. It would seem that if the waterproofing is compromised as mine clearly is, that water can be trapped inside where WD40 cannot get at it and the water cannot evaporate off.
It would seem that when doing water crossings the water hits the front diff and flies straight up into the electrics. I have a secondary alternator low down and it also splashes the water around - some plastic shielding will help but the issue of waterproofing the ignition is also important. In a basic system you could pull the leads off and remove the dissy cap and give everything a dose of WD40 and be on your way - but not so easy on the waterproof system as every lead is screwed in.
So those 101 peoples with their 24v systems still intact - do you have any issues? Secondly have any of you replaced the waterproof coil with an after market one and what did you use?
I have bought a bosch holden dissy converted for use on the rover v8 and it has an early electronic ignition attached. If my does not come good - I will just put this system in and use it.
Cheers
Garry
101RRS
20th January 2010, 03:44 PM
At the moment I am working through the various ignition components with workshop manual in hand.
The at the start of the electrical section of the workshop manual it says that there is a 10 volt coil is fitted to 24 volt models with a filter and voltage dropper. I have located the filter - a large box under the coil that has switched 24v going in and 24v coming out that goes straight to the coil. I cannot locate any 10v dropper and in the wiring diagram and later in the manual there is no mention of a dropper. Can I assume that this 24v-10v dropper for the coil is a mistake in the manual intro and in fact on 24v models the coil does in fact receive a full 24v?
Also - the filter box does not seem to serve any real purpose in civilian use - no radios so can I just bypass it and run switched 24v straight to the coil?
Thanks
Garry
toad
20th January 2010, 04:13 PM
Hi Gary,
glad you got your bus home ok, It looked a bit forlorn on tow - at least we did not use a none LR product to tow it with:o.
As far as I am aware the 101 ignition coils were always a nominal 12 V dc (or 10V dc in this case). You need to use an "R" coil; i.e Bosch GT40R, which is designed to run on 9 V dc full time. A resistor is switched in (in normal cars) during running, and out during cranking. If you use a normal 12 V coil this will result in a weak spark and poor starting!
I have a spare dissy here if you wish to put a civy one in and have a play.
Regards,
Rick.
101RRS
20th January 2010, 05:16 PM
Hi Rick,
The "water proof" coil is not so waterproof - finally got it out and it is full of water - seems it got in through via the mesh shielding on the leads.
While not detailed in the workshop manual the user handbook says that there is supposed to be a ballast resistor contained in the filter box under the coil so that the "filter box" with its choke and capacitors suppresses power going into the coil and reduces it to 10v. Mine does not have these capacitors in it and mine has 24v in and 24v out not 10v.
I think I need to sort out what power I have going to the coil before I go tinkering with the dissy.
It is all so confusing - it looks like my coil has been running on 24v not 10v but is confusing.
Garry
101 Ron
20th January 2010, 06:04 PM
the series three exarmy landrovers as supplied to the army were suppressed like the 101 as most of them were FFR.
In service the ignition system on the series three six cylinder gave trouble and alot towards the end of there army life were converted to normal high tension leads and coil etc. ( at unit level )
the army series three was 12 volt.
The ignition coil out of a army series three is what you are looking for and they often come up at swap meets new for cheap prices as most series three owners don't want to know but it.
DO NOT REMOVE THE INNER DIST CAP FROM THE OUTER ALLOY HOUSING AS IT WILL NOT GO BACK TOGETHER WITHOUT DAMAGE.
You will most likely damage the cap trying to get it out too.
IF you run 24 to a 12 coil it will burn out the points and coil.
You will find the leads will be the main cause of your grief.
(shouldn't have given me the spares you had?????)
I was thinking of replacing the inner HT lead with a old fashion copper HT lead and solder the ends in place etc.
I have not had time to try this.
The HT lead it self will work in water..........its just where the connection are that need to be sealed.
From memory there are O rings in these fittings and replacing them will help.
On my 101 I looked at moving the coil to a different location.....ie up in where the air filter is.
All the places I found has issues with wiring or access.
I ended up moving the coil forward from its standard location to between the side of the chassis and fan shroud as this gets it forward and out of line with the fan blades and water.
The ends of the civie type spark plugs and leads I have sealed with motor bike spark plug caps as they are fairly water tight.
Not water proof , but water resistant
101 Ron
20th January 2010, 06:38 PM
My current set up took this..........but it did lose one or two jugs for a little while and sorted itself out a few miles down the road.
https://www.aulro.com/afvb/images/imported/2010/01/588.jpg
Note garry your coil must be getting 12 volt as 24 volt would cook things in very short order.
The main problem with suppressed leads is the fact that the shield and the high tension conductor are very close together, especially at the connections and rely on every thing being in good condition.
The same goes for the low tension side of thing because of the shielding.
I have some the British military manual on how to fully prepare a 12 volt and 24 101 for submerged operation.........only takes a few days to do.
You have plenty of time these days garry...:D:D
I will say again....the best way with a 101 is to take any water at a crawl if possible and will easily get to the top of the tyres before ignition trouble.
It is surprising how and long nose and bonnet keeps a engine dry.
The bonnet and forward motion of the vehicle forms the bow wave and a depression behind it with a air bubble under the bonnet keeping the engine dry for short periods of time.
Forward controls do not have this effect.
Think of the last Stockton run with the Pinzgauer stopping in fairly shallow water crossing with every thing driving around it including the 101s.
The reason is the the pinz went that little bit too hard speed wise. ( I think the pinz ignition was suspressed too)
Remember the Quarry and I tried to go in the mud hole where the pinz only just made it though.
I crawled in fairly deep slowly.......though twice about doing what the pinz did and backed out with no problems.
No bonnet......drive differently.
I learnt this the hard way too with me trying to dry out a difficult to access ignition system on the side of the road.
101 Ron
20th January 2010, 06:48 PM
The other thing I have done in fitting a civie igintion coil is using a Bocsh transformer type as they are very reliable, but the important feature for a 101 is the low tension and high tension connections are at the opposite ends of the coil making curent leakage with water alot harder, unlike a standard civie coil with the low and high tension connections beside each other waiting for mositure created flash over.
101RRS
20th January 2010, 07:27 PM
Mystery solved - she is now running.
As`mentioned the coil was full of water - remove water and it works:D. Once it lets water in, it will not let it out unless the coil is removed and all the leads taken off it. It looks like the previous owner also had problems as there are two holes drilled in it that were filled with silastic but covered by dirt. If she stopped pull out the silastic and squirt WD 40 in the top hole and let the lot run out the bottom. It is a good idea with some modification.
I have also solved the mystery of 24v going to the coil - when the power is actually connected to the coil so the resistance of the coil is in the circuit power drops to 10v.
Rick - I will see if a Bosch GT40R coil will work on 10v or if a small additional ballast resistor is needed to drop it to 9v - would be a good backup if needed - the original 101 coils are about $500 but as Ron said I might get one at a swap meet - I also worked out how to put up the rotten BCF sun shade we were struggling with in the storm on Sat. It is easy when you know how - thanks for your help.
So - I need to put thinking cap on and think like water and make some up some new LT leads, waterproof the joins, ensure the coil remains sealed - but if water does get in how to get it out without having to dismantle everything. Some issues with the dissy were also highlighted when looking at it - the dissy does come out of the aluminium cap but a lot of care is needed.
Thanks
Garry
101RRS
20th January 2010, 07:41 PM
You will find the leads will be the main cause of your grief.
(shouldn't have given me the spares you had?????)
I was thinking of replacing the inner HT lead with a old fashion copper HT lead and solder the ends in place etc.
I have not had time to try this.
The HT lead it self will work in water..........its just where the connection are that need to be sealed.
From memory there are O rings in these fittings and replacing them will help.
I don't need that stuff and you should be able to make something out of them. I would rather they be used than lying around at my place - better cluttering up your garage rather than mine.:)
My HT stuff all held up well - most has already been changed to normal leads with the waterproof ends on - just what you are considering.
It was the low tension stuff that let me down - that is what let the water into the coil - when playing with it this afternoon, the insulation on the switched power cable to coil just crumbled and the bare wire shorted on its sheaved outer layer - is now plain red wire soldered into the proper water proof ends.
I think the waterproof system is the way to go but without the original radio suppressed cable - the outer braided covering causes too much grief ands is where the water gets in.
Garry
101 Ron
20th January 2010, 08:49 PM
I took these to night.
Both were purchased from a seller at the menagle steam museum at different times with my 101 in mind.
I believe they are army series three items.
Both are 12 volt.
One is new and the longer one is secondhand marked tested OK.
Garry you are welcome to the older one.
https://www.aulro.com/afvb/images/imported/2010/01/582.jpg
https://www.aulro.com/afvb/images/imported/2010/01/583.jpg
https://www.aulro.com/afvb/images/imported/2010/01/584.jpg
https://www.aulro.com/afvb/images/imported/2010/01/577.jpg
https://www.aulro.com/afvb/images/imported/2010/01/578.jpg
101 Ron
20th January 2010, 09:09 PM
Bosch transformer type.
http://www.supercheapauto.com.au/online-store/products/Bosch-GT-Transformer-Ignition-Coil-GT40-T.aspx?pid=8841#details
Note spacing of the terminals to a normal type coil .
http://apps.bosch.com.au/products/saa/ignition_coils.pdf
The bosch normal oil filled coils do fail due to vibs whisle the transformer type do not.
They do not look cool in the engine bay of a old truck....but on a 101 you can not see it any how.
On my 101 I threw the ballast resistor as it is not needed if the rest of the wiring is OK.
To do this the coil must be changed from a resistor type to a non resistor type.
throwing the ballast saves a whole lot of wet low tension wiring.
the problem is your vehicle is 24 volt and you need the ballast for the drop from 24 to 10/12 volts.
Do they made a 24 volt ignition coil ?
101 Ron
20th January 2010, 09:18 PM
Ignition Coils - Replacement Ignition Coil 24 volt <br>Fits 50-66 M38, M38A1 Jeep (http://www.kaiserwillys.com/product/1235/willys_ignitioncoils)
Ignition Coil 24 Volt, 118712 / 11663066 (http://www.eriksmilitarysurplus.com/igco24vo11.html)
101RRS
20th January 2010, 09:35 PM
https://www.aulro.com/afvb/images/imported/2010/01/577.jpg
https://www.aulro.com/afvb/images/imported/2010/01/578.jpg
That is a 101 coil.
Garry
Dave Jump
20th January 2010, 09:47 PM
For ref, my UK 101 had a 12 volt coil , dizzy and leads with 2 dropper resistors in series which worked fine. When the 24volt set up is working its fine but as Gary now knows when it plays up it can be tricky. My Oz 101 has been converted by a previous owner and now has a 24 to 12 converter powering a 12 volt dizzy, coil and leads which is working ok except the bush in the dizzys pretty flogged out and the rotor arm lobs a bit.
Lets not forget the primary function of the 24 volt system was for radio supression.
101RRS
20th January 2010, 10:51 PM
Hi Dave - how is the 101 going?
Now that I have sussed the problem I will leave it as it is but hopefully drown proof it - wishful thinking maybe. Some splash guards between the front X member and the engine will also help.
I have bought a complete 12v dissy/electronic ignition set off ebay and will put them in with my spares with a cheap ebay 30 amp 24v-12v reducer. If the 24v system plays up later then I will put it in.
Garry
Dave Jump
21st January 2010, 07:08 PM
Hi Gary
The 101's good, just drove through Melbourne CBD to pick a cupboard up. Great fun, 2nd gear starts, frightening commuters with the classic 101 rumble.
Has your 12 volt dizzy got the right drive dog on the end for the 101? Worth checking before you need it.
Mick_Marsh
21st January 2010, 07:37 PM
Hey Dave,
Were you driving up Victoria St/Pde at about 4:30 this arvo. A workmate rang me on his way home to tell me he'd just passed a 101 going the other way.
101RRS
21st January 2010, 07:39 PM
Has your 12 volt dizzy got the right drive dog on the end for the 101? Worth checking before you need it.
I thought it was the same as other early RR 3.5 V8s - is it different?
Garry
Dave Jump
22nd January 2010, 02:24 PM
Hi Mick
Yeah that would be me. picked a tool locker up from Just tools in South Melbourne. They wanted $50 to deliver it to Northcote so took the 101 for a spin.
Hi Gary
Yes your right, early 3.5 as it drives the early oil pump. I guess you've got a dizzy with an electronic conversion rather than the later electronic type.
101RRS
22nd January 2010, 02:46 PM
Hi Gary
Yes your right, early 3.5 as it drives the early oil pump. I guess you've got a dizzy with an electronic conversion rather than the later electronic type.
What I have got is a Holden Bosch dissy that has the rover drive on the bottom. It came out of a mid 70s RR. It has an early pointless electronic ignition that can easily be converted back to points if the electronic side was to fail.
Garry
101RRS
23rd January 2010, 01:24 PM
I have re-waterproofed my standard system with the help of silastic and heat shrink plastic tube. I ran the truck with the hose directly on the electrics for 10 minutes yesterday and no issues.
The spare dissy and associated coil and electronic module will go into my spare parts box for the moment. If my system plays up again then in it goes.
The coil and ballast resistor from the 12v system should be a straight replacement for my coil in the 24v with out additional bits. The 101 coil runs on 10v with its ballast resistor and the spare runs on 9v with its ballast resistor.
Cheers
Garry
Powered by vBulletin® Version 4.2.4 Copyright © 2025 vBulletin Solutions, Inc. All rights reserved.