View Full Version : 101 Wiring Nightmares

06-13-2007, 01:38 PM
Thank you for the comprehensive list of conversion parts. You have done the most difficult part of the job. The rest is just time, of which I have very little just now, probably later in the year.
Having turned most of my attention to the engine, I had not looked into the wiring; subsequent to your mention of fuses, wiring harness, etc., I had a look under the dash. What I saw was not particularly pleasing! Above the foot feed is a solid state relay with about 6 red wires plugged into it; those wretched crimp connectors with the insipid blue insulators are everywhere. I haven’t found a fuse “block” only one inline fuse above the relay. Yukk! That mess will have to wait until I acquire a manual and a circuit diagram.
Can I use the Range Rover exh, manifold and gaskets to replace the R/H? I’m guessing the configuration would be the same as well as the flange joint(??)
Appreciate all the info. Thanks

06-13-2007, 04:27 PM
Unfortunately the manifolds on a 101 are unique as they exit fairly high up at the rear of the engine whilst a RR mainfold exits straight downward from the middle IIRC. This is to clear the chassis rails. I believe finding replacement manifolds is one of the holy grails of 101 owners. Welding one is a very skilled art because of the casting and, unless done properly, they tend to rapidly crack and fail again. If you get stuck give this crowd a call although I think the manifolds are take offs. http://nkrecovery.co.uk. I haven't done business with him yet but his prices are reasonable and he is well known in the UK 101 circles. The tanking value of the dollar does not help us transatlantic owners right now. The gaskets I use are off a Disco 1 and are ERR6733. Our host sells them but I not going through their numbering system.

The electrical thing sounds like a nightmare. I should point out that even the original harness does not look very pertty under the dash! If the harness has been butchered badly it might be best to just go with a Painless universal harness. My harness was original but the instrument section was badly damaged due to a short. I actually like the Lucas wiring coding so, with the help of a reference harness provided by Bill at GBR, I got the right wires and built a new harness. It was theraputic in a way I suppose but I am not sure I would do it for the entire truck. The wiring diagram is not too complex once you get in there but there are a few upgrades that can be made. If you haven't done so already, join the yahoo 101 owners group. http://groups.yahoo.com/group/101/ The moderator can be quite picky about acknowledging you but it is full of useful info including a PDF of the wiring diagram.

If you have problems PM me and I will try and help. Good luck.


06-18-2007, 10:12 PM
Gregor -
Appreciate the link. Have sent an inquiry - no reply as yet.
I am in agreement with you on the wiring harness, except locating wire with the Lucas colour coding might be a road block. The re-wiring itself is a challenge, but mostly a time thing - I am saving all of this good info.
One of the foremost considerations here (with any vehicle) is fuel economy. Gasoline is close to $5.00 per gal(imp.). My 109 had an overdrive and F/W hubs - together with a diesel engine - provided 28-30 mpg. (imp.). You mentioned changing transfer gears, and I see there is an O/D available. Also, it seems it is possible to change the transfer case to part-time. I don’t want to do a diff ratio change at this time. Could you comment on any or all of the above?

06-19-2007, 10:49 AM
For Lucas coded wire I use British Wiring. They also sell all the connectors you need etc. The original owner of the company just retired so they sold it to a new operator. In the past they were very good. I also found that Painless Wiring PowerBraid makes a good sleeving for any new harness work.

As for improving fuel economy - well you have to understand that you are driving the aerodynamic equivalent of a brick outhouse using using big heavy 9.00x16 tyres. You will be doing very well to beat 15mpg with the original V8 installed. The best and probably cheapest way to save fuel is to make sure the truck is in top notch tune. Also try avoid winding her out on the freeway as she will guzzle fuel faster than an ASU tart on Mill Ave on a Saturday night. You could convert to diesel with good results but recouping your conversion cost on fuel savings alone will take a long time.

As far as gearing goes:

The overdrive is available used and was originally fitted to an early Range Rover with LT95 box. It is not available new anymore so you have to take your chances buying a used unit. Installation is fairly simple with the only complication being fabbing up an actuator bracket, getting the right lever to mount next to your transfer selector and then having a bowden cable made up. I have also heard the rumour that 101's tend to eat OD's but a lot of people still run them. The plus side is that it gives you the most versatile set of gear ratios.

The transfer gear swap is the strongest and most reliable way of raising your gearing. I used the tallest set I could which was .9962 out of an early Range Rover. This has made the truck a lot more driveable on the road as you can use first gear for more than 2 feet off the line and hold the remaining gears longer without winding out. You will want to give your engine a look over to make sure it is fresh to be able to pull that tall a gear set. There is a whole range of ratio options so you can choose someting more intermediate if you like. As part of a complete engine rebuild I put in a set of high compression pistons to raise the CR to 9.3:1. Along with a new cam this has given the 101 a new lease of life and she now goes like a train. If I could stop burrying the throttle I am sure there are fuel efficiency gains to be had there. There is also a Nick Kay conversion to adress a potential issue with the thrust washers in the transfer box that can be included at the time of the swap. It also does not affect your low ratio so off road remains as good as the original. It is also most likely the cheapest way of increasing your gearing.

I have also heard rumours of people adding selectible four wheel drive to the gearbox although I have never seen the engineering behind it. In my opinion this is not a great idea. Any extra length on the front output shaft is only going to compound the drive angle issues on the front prop shaft. You will start eating UJ's. Secondly, you will still be pushing the drive train unless you add freewheeling hubs. I am not aware of any off the shelf hubs that will fit the 101 and having custom ones made up will be expensive. Finally, you will have to have the toe in adjusted for operating as a 2wd. If you want to check for any potential savings down this road I would simply remove the front prop shaft for a while. If I am doing a long road trip I will do that but it is more so that I don't have to listen to the prop grumble than any fuel savings.Cheers