Getting the power around a Meyers Manx Tow'd - Start to Finish !

[BuggyBrad]

Ok so after looking around I seem to see a lot of questions and not many answers. I am not sure why but it seems there is a huge lack of information, pictures and details on what it takes to effectively wire a vehicle for offroad fun and reliability.

Now before I begin I will put this disclaimer up front to hopefully avoid arguments:

1 - This is being done on a Budget and is not a TT with a $30 000 loom.
2 - This is NOT MIL SPEC ...
3 - I do not wire for a Job and am open to input and suggestions
4 - This is not the be all and end all it is just one option.
5 - If you want to post negative criticism then I ask you at least Ball up and post pictures OF YOUR work before you start critiquing mine. To many sit back and pass comment on stuff they themselves have no idea how to or skill to do so support what you say with pictures and I will happily take it as constructive.

Most of all I am doing this to hopefully help out some others and learn something myself.

I am flying half way around the world to do this job so only have a few hand tools and parts with me so it will not be super complicated or fancy and should be achievable by most people out there.

 

[BuggyBrad]

So the car which is a Meyers Manx Tow'd belongs to a Mate of mine who lives in Australia and will be coming over to race the Mexican 1000 with us in April. He heard I was going to be in the area for a few weeks so asked if I could wire his buggy while I was there. I said sure and it went from there.

This is what I have to start with via email ..

Ok ,

Switches are to be Stainless / Chromed Brass with all switches when mounted in the up position in dash , with the following switches
Parkers / Headlights (HID) OFF ON ON

Wipers ( 2 speed 1500 ) OFF ON ON

Thermo fan ( mounted in nose of car in front of beam ) ON OFF ON , when on up is also wired through thermal switch near engine , when on down thermal switch is overridden and fan is on when ignition is on

Interior light to be an led unit mounted to the underside of Alloy roof panel OFF ON

LED Light bar , mounted on roof above windscreen OFF ON wired through high beam

Horn OFF ON ( momentary )

2 CIG lighters with power 100% time , one of in dash drawing from main battery , one of in rear of car most likely in bottom of stock battery well drawing from second battery

Headlights are to be mounted near tops of shock towers with front indicators just under

High beam to be switched through button on back of early beetle indicator stalk

Fuse box , light balasts , any required relays , ICOM remote UHF to be all mounted in alloy panel above legs / feet under bonnet , plenty of space approx 400 x 600

Tail lights are mounted in ends of rear bar and are an LED unit including indicator , brake tail , and reverse , with reverse just wired into the Kombi box switch ONLY

Electric Fuel pump mounted under stock Towd battery tray

Starter motor ( Cranky kit )

Dual battery's ( Odysey ), mounted just above rear torsion housing one on each side , controled with a dual VSR

Guages are Speed hut with the following guages

GPS speedo / tacho combined
Oil pressure
Fuel level with VDO sender in tank
Oil temp
Volts
Head temp

Distributer is a Magna Spark Digital and coil will be mounted on Jaycee alloy fuel pump block off plate .

 

[BuggyBrad]

Sounds like most jobs a guy gets a list of parts with interesting and often useless descriptions of what current draw and operational parameters needs to be allowed for.

So step 1 is to create a list of each of the components which will be on the buggy and find out what max amp draw will be at start up and under load. As part of this I will also need to work out wire lengths as it has a effect on what is needed.

For the job I will be using 3 gauges of TefZel wire which I purchased from ProWireUSA.com before leaving the USA. Colour is irrelevant as I will be wrapping it in heat shrink anyway and using Deutsch with pin out numbers and keys as required. I also have access to a single run or 8ga which will be used for primary feed and charge circuit.

For the purpose of this thread I will just say the loom will be 15' and use that to cover current draw over the loom length. This will cover every wire and allow redundancy.

I have:

M22759/16-14 - 20 AMP

M22759-16-16 - 12 AMP

M22759/16-18 - 8 AMP

I will be using Deutsch DT Series connectors and a mixture of single, and dual walled heat shrink. Main loom and any areas of concern will be double wraped and Raychem DR-25 will be used.

Strain relief will be used on the back of any connectors which I am concerned about and most likely be done with dual wall over the shell and internal service loops.

Fuse Box will be a BussMan un bussed unit with I think 10 blade fuses and 6 relays. I will confirm model number when I get to Australia. The nice people at the TSA did not appreciate me trying to fly with wiring tools and a fuse box in mu carry on, who would have though lol.

Switches are MilSpec units (https://www.prowireusa.com/c-21-sealed-toggle-.aspx) as the buggy will see a lot of high corrosion exposure due to it playing on the beach just feet from the waves and in fact with the way Andrew drives it will no doubt end up in the surf before long .

 

[_]

Brad, just a few thoughts...

1) You do not need an On-Off-On switch for fan operation. You only need an On-On as an override to the thermal switch. The switch will select between the thermal switch and GND (or +12V depending on how you wire the vehicle.) Insure the relay's coil sources power from the ignition switch so the fan will only operate with the ignition "ON." This should be true whether in normal mode or override mode. (This is also be true if you are using a redundant fuel pump. Position-A = Pump-A, Position-B = Pump-B, )

2) RE: Fuel Pump Activation. This has been discussed many times through the years (Although most of the threads have been lost when Klaus's server died.) and I'm sure your professionalism would not allow you to do it any other way. But, I will re-address this issue as others who may be reading this thread who may not be as safety savvy and may not know this. "Do Not Wire The Fuel Pump (and/or Fuel Pump Relay) Directly To The Ignition Switch." Either use an Oil Pressure Switch with a priming override -or- a Fuel Pump Safety Switch to control fuel pump operation. If wired properly, both of these devices will insure the fuel pump will not run on when the engine stops running. Too many cars have gone up in flames along with several very close calls of severe injuries, a result of fuel pumps being controlled exclusively through the ignition switch position. The oil pressure switch is obvious on how it operates, no oil pressure = no signal to the fuel pump relay. The Fuel Pump Safety Switch operates in the same manner as an ECU, providing both automated 3-sec prime with activation of the IGN switch and a continuous run with both an IGN and a Tach Pulse. Contact me via PM if you wish for greater details.

3) Most wiper motors have a feed back signal or an actual park wire which allows the wiper to park itself without chasing the wipers with the switch to their DN position. This feature can be incorporated into your toggle switch operation, provided the appropriate switch is used and wired properly to activate the park mode. Send me a PM if you want help with this.

 

[BuggyBrad]

Thanks for the input, I should have made it a bit clearer, the above email as such was what Andrew sent me as the requested starting point, not what I actually intend to do. What I was trying to show by posting it up is more often then not what a guy wants in his wires and what he gets are often far apart.

It is good to get input on it though as a lot f people do some very interesting things with their looms. I like the oil pressure switch for the fuel pump.

 

[BuggyBrad]

So after a 14hr flight I head out to SteelArt Creations workshop to see what the starting point is like. I was told it would be ready to go with everything mounted.

Funnily enough his definition of ready and mine are a little further apart that I hoped for.

Not to worry Andrew bought me a Bacon and Chees Pie for lunch so it was worth the trip, man I wish they had Meat Pies in the USA.

So after discussing the way ahead with Andrew I left him a list of to do's before I could start. I generally try and avoid mounting stuff if possible as it is very personal so I prefer the owner does it. It should be done by mid week so I should be right to start on the weekend.

In the mean time I started getting a list of the bits he is using and will collect Amp draws.

 

[200MPHTape]

Complements of 01_el_tiburon,
http://www.race-dezert.com/forum/attachment.php?attachmentid=9352&d=1131420289

 

[BuggyBrad]

Complements of 01_el_tiburon,
http://www.race-dezert.com/forum/attachment.php?attachmentid=9352&d=1131420289

Thanks for that it is always good to see what others do.

 

[BuggyBrad]

So after visiting the shop and leaving a list of todo's I got a text message from the owner with a few pictures

So it is looking better. One thing to note is with gauges ... now when you wire a car there are two things you need to take into account that many forget.

Firstly is serviceability, here what I try and do is think about things breaking and needing to be replaced. There is no point doing a super cool loom if you can't remove a component and swap it out without cutting the loom up. With this is mind I always plan to make each component as removable as possible within reason.

Secondly is accessibility, a lot of the cars I work on have not yet been painted. This means that the loom needs to be removable once it is done. Deutsch connectors are great for this as when you de-pin the plugs the od of the pin is very similar in size to that of the wire so you can pull it back down if needed. Biggest issue with this is that it stops you pulling a shell back on so u need to find a happy medium. The other part of this is make yourself as comfy as possible when you wire. If you look at the above pictures you see 3 main areas, switches, gauges and fuses. The switches all pull from front to back as to do the fuse box's. The gauges ,however, do not they pull out frontward and they have minimal access to the rear. Because of this I will make a removable panel to put them in so the panel will come out as a unit with a single plug. This will allow me to wire it up on the bench and make it cleaner. The gauges being used are from SpeedHut which is good as they have a life time warranty and are full callibratable but is bad as they do not have plugs they have wire tails. What this means is that you have to either make the decision to wire as a complete unit and if you get a failure you are cutting wires or you need to put a plug on each gauge so it can be removed.

In this case due to the harsh environment in which the buggy will live ( sea salt and beach sand ) I will look at both options as less plugs is good but limits replacement options.

I should be running wires in the next few days so will keep you posted.

 

[CMA GUMBY]

Not to worry Andrew bought me a Bacon and Chees Pie for lunch so it was worth the trip, man I wish they had Meat Pies in the USA

http://www.bettycrocker.com/recipes/impossibly-easy-bacon-cheeseburger-pie/9ecc3aa7-c0c5-4811-b5e2-1596c77dc074

I used stew beef, and partially shredded it. Of course, MORE bacon. Sorry for the highjack.

 

[BuggyBrad]

Not to worry Andrew bought me a Bacon and Chees Pie for lunch so it was worth the trip, man I wish they had Meat Pies in the USA

http://www.bettycrocker.com/recipes/impossibly-easy-bacon-cheeseburger-pie/9ecc3aa7-c0c5-4811-b5e2-1596c77dc074

I used stew beef, and partially shredded it. Of course, MORE bacon. Sorry for the highjack.

Man I got all excited cause I thought you were posting a link to someone who sold Meat Pies in the USA... I don't want to cook my own I want to buy one in a paper bag from the local servo

 

[SoCalRally]

Man I got all excited cause I thought you were posting a link to someone who sold Meat Pies in the USA... I don't want to cook my own I want to buy one in a paper bag from the local servo

Threadjack on: Deli SA (South African) in Kearny Mesa usually has a selection of pies e.g. steak & mushroom, steak & kidney, chicken & mushroom, cornish pasties, etc. ready to go.

http://www.sandiegofood.net/2012/09/deli-sa-south-african-in-kearny-mesa-san-diego.html

 

[y2kbaja]

Complements of 01_el_tiburon,
http://www.race-dezert.com/forum/attachment.php?attachmentid=9352&d=1131420289

Just a note on this wire diagram, it has the fuel pump NOT controlled/powered from the ignition switch as recommended above. I would wire mine to the Oil Pressure switch but if the oil level is "low" and the light fllickers wouldn't that cut the power to the fuel pump?

I took this and adjusted it to my car (attached)

 

[BuggyBrad]

The oil pressure cut off switch usually have a feed from ignition and start so it starts the fuel pump when it is cranking regardless of oil pressure. In regards to the low oil if the oil pressure drops below 5 PSI on the one I am using I would expect the fuel pump to cut out.

 

[BuggyBrad]

After talking to Andrew in depth it was decided to make the loom modular so it can all be removed. I expect this will add a few hundred dollars to the job due to extra plugs but it will mean it can be ealityh replaced and modified as time goes on.

In relation to the gauges Andrew wanted to keep them through the dash so this means adding a plug to each gauge. The only one which doesn't get a full plug is the cylinder head temp as the probe needs a specific length sensor wire.

So starting with the gauges, luckily for me my mates workshop ( SteelArt.com) in Brendale Australia has an Arclight CNC Plasma so I was able to easily and quickly cut out a secondary dash face to hold the gauges in place.

It is amazing how simply using Bend-Tech SM and the ArcLightCNC made pumping out the panel. Once done I could simply fit the gauges and hold them in place.

with the gauges in place it was simply a case of working through and adding a DT connector onto each small loom.

I always write on the back of the gauges so that I can tell what they are from each side.

 

[green787]

Here is a diagram I made for VW wiring without running the headlights through the ignition switch.

 

[BuggyBrad]

With the gauges in place and tails fixed it was time to start looking at where to next. With most cars I like to start at the outside and work my way in. As the Tow'd will be made up of several smaller looms I started at th eback with the rear bar loom.

It was laid out from the lights to the joins.

I usually terminate one end pretty early so I can set lengths. With the Deutsch Connectors it is easy enough to pull a pin out and pull it through if you need to.

Once I have it laid in place and tape at the joins you can pull it out and lay in on the bench.

Then you stagger your butt splices and heat shrink them.

To Heat shrink them I use some dual wall medium. The main reason for using this is so that any strain is moved away from the splice and the glue ensures that nothing gets in. You must make sure you stagger them so you don't end up with an ugly ass hum in your loom.

 

[DesertGuy1]

Since many electrical problems can be sourced to connections... what is the thinking behind adding more? Looking at the last pic posted, why wouldn't you simply terminate the wire at the connector pin?

 

[BuggyBrad]

Since many electrical problems can be sourced to connections... what is the thinking behind adding more? Looking at the last pic posted, why wouldn't you simply terminate the wire at the connector pin?

Not sure if you are looking at the picture correctly but you can't terminate more than one wire into a pin. The Butt Splice is there as it is on a branch as it goes on to feed multiple circuits. You can see it better in the second last picture, there are two wires going in and one out into the DT.

The reason for so many plugs is because the entire loom needs to be removable so the car can goto powder coat etc. It is not ideal but I have never had any issues with the DT series Deutsch stuff. Most of the issues I have seen with termination relate to people using cheap crap and not terminating it correctly.

 

[green787]

Not sure if you are looking at the picture correctly but you can't terminate more than one wire into a pin. The Butt Splice is there as it is on a branch as it goes on to feed multiple circuits. You can see it better in the second last picture, there are two wires going in and one out into the DT.

The reason for so many plugs is because the entire loom needs to be removable so the car can goto powder coat etc. It is not ideal but I have never had any issues with the DT series Deutsch stuff. Most of the issues I have seen with termination relate to people using cheap crap and not terminating it correctly.

Normally we don't do that here in the States...