The Ford to Cummins Conversion Thread

Clearing away all wires, pipes and controls

Loads of wires. Loads of tubes. And they all need to be disconnected. I’m ashamed to say that I don’t actually know what a lot of them do. This is mainly because finding detailed information on these engines has been surprisingly hard, and once I decided to switch to the Cummins – for which ample, clear literature is easily available – I gave up trying to work it all out.

Piggy-backing wires here and there have added to the confusion:

PipesandWires1.jpg


And what do these pipes and wires do – connecting to the air intake crossover and intake manifold?! In due course I will trace some of these back to the dashboard or wherever else they go…

PipesandWires2.jpg


Meanwhile, elsewhere in the engine compartment – what a mess! Once upon a time, the wiring might have been neat and tidy. Over the years, wires were added by owner after owner. Gadget after gadget, rethink after rethink.

PipesandWires3.jpg


Each time, more spaghetti was added with the aid of cable ties of varying colours and sizes. In some cases, redundant wires and water pipes have been cut off and left in situ. A nightmare to understand and remedy problems within the safety and comfort of the marina – never mind out at sea.

PipesandWires4.jpg


I’ll be fitting square-section white plastic cable conduit to the underside of the longitudinal cabin floor beams, leaving wires loose inside so they can be changed and cleaned at will.

Trunking.jpg


As and when they need to exit these conduits, they’ll be wrapped in some white cable wrap:

WhiteWrap.jpg
 
This is déjà vu from my refit. I recommend you do everything you can in the engine bay once the old block is out the way. Don't miss the opportunity of having such easy access.

I also considered trunking for new cables but decided against it. Although not quite as neat, it does allow easier access to wires as you will inevitably need to change or check things over the years.
 
I also considered trunking for new cables but decided against it. Although not quite as neat, it does allow easier access to wires as you will inevitably need to change or check things over the years.

What did you use instead of trunking? I can't really think of any other way to keep it high up and out of the way other than cable ties. I'm thinking that when I need to make changes over the years I can just remove the trunking capping, pull out already loose wires, put some more in, etc.
 
I used these fixed up at intervals with small screws to the underside of the floor joists, then lots of cable ties. Has proved to be very succesful in my view. Just about visible in the photo.
 

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Not a fan of cable trunking in engine installations. Better bet would be split flexible conduit. Also hate to see lucar connectors. For joining your main harnesses to accessories, small applications up to 15 amps would be better served by Tyco AMP superseals available in single and multiple connectors. All my installations are tailed with these including the sound system and speaker wires.



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A very good source of cabling and accessories is Beal automotive. I got my AMP superseals at RS Components.
 
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I have a rule on the boat, wires and pipes - no joins, one continuous length for each job.

When do you need the CAD for the adapter mounting plate? How long have we got?
 
And what do these pipes and wires do – connecting to the air intake crossover and intake manifold?! In due course I will trace some of these back to the dashboard or wherever else they go…

PipesandWires2.jpg

Looks like a coldstart device of some kind; is that a fuel supply line?
 
I have a rule on the boat, wires and pipes - no joins, one continuous length for each job.

Absolutely! Now I have the chance to make sure they're the right colour, too, and not just made up from whatever lay around within three feet!

When do you need the CAD for the adapter mounting plate? How long have we got?

Not a month or two, thanks - want to have a big clean up before I place the 'new' engine in and measure things up...
 
For joining your main harnesses to accessories, small applications up to 15 amps would be better served by Tyco AMP superseals available in single and multiple connectors. All my installations are tailed with these including the sound system and speaker

Have a look for Sumitomo connectors.the hw series is an alternative, as used by the big jap motor companies. Suitable for smaller wiring sizes, with multiway plugs. They do two connectors terminal sizes, one for 0.3 to 1.25 mm sq, another for larger....
They just feel more robust to me, but each to there own of course.
 
Loads of wires. Loads of tubes. And they all need to be disconnected. I’m ashamed to say that I don’t actually know what a lot of them do. This is mainly because finding detailed information on these engines has been surprisingly hard, and once I decided to switch to the Cummins – for which ample, clear literature is easily available – I gave up trying to work it all out.

Piggy-backing wires here and there have added to the confusion:

PipesandWires1.jpg

Nice work there, just had the chance to go through the whole thread, well done and take it easy one step at a time!
Took me over a manmonths worth of work to figure out ALL the cabling, remove around 40kg or redundant cabling (not exagerating!) and sorting out the cables in the existing conduits. Good thing is that once done, you do know what does what in your boat which is v. handy imho ;)

Meanwhile, elsewhere in the engine compartment – what a mess! Once upon a time, the wiring might have been neat and tidy. Over the years, wires were added by owner after owner. Gadget after gadget, rethink after rethink.

PipesandWires3.jpg


Each time, more spaghetti was added with the aid of cable ties of varying colours and sizes. In some cases, redundant wires and water pipes have been cut off and left in situ. A nightmare to understand and remedy problems within the safety and comfort of the marina – never mind out at sea.

PipesandWires4.jpg

had that in the e/r where there was a nice clean conduit on the salon above hidden nicely behind a cabinet that the PO never removed to access the cabling but instead hang everything on the ceiling of the e/r...
In hindside, it makes sense to attack cables on a per tie-wrap basis :D
I'll explain: DONT cut all tie wraps, letting all the cabling loose, you'll get lost! Go one at a time (it's more tedious I know, but helps you figure out what's going on) Trace them all the way to engine and helm/cabins whereever, figure out what they do (In my case, most DID..) and rip them out if not needed (95% of the case in mine)
Also check the cables getting + straight from the starter motor!!! FFS, unfused and ready for problems :(

I’ll be fitting square-section white plastic cable conduit to the underside of the longitudinal cabin floor beams, leaving wires loose inside so they can be changed and cleaned at will.

Trunking.jpg


As and when they need to exit these conduits, they’ll be wrapped in some white cable wrap:

WhiteWrap.jpg

Exactly the original 36yo setup on MiToS. Only difference was that the conduit had oblong slanted openings on the sides, making threading cables out and in a breeze. Also changing the position of the in/out was uneventful and clean.

good luck!

cheers

V.
 
The black conduit looks nice, but its biggest problem in areas with vibration is it frets the cable insulation inside causing loads of ridges down to the copper, came across this on volvo trucks circa 1993, the damage then allowed water to short out and blow up the engine ecu!
Cabling is a big big problem on current trucks, they use cable way to thin and the stuff fractures and corrodes so fast its unreal, the current engine looms are moulded, then some sort of silicone injected to stop he cables inside rubbing.
The newest trucks have now gone back to the black conduit!


Lynall
 
For joining your main harnesses to accessories, small applications up to 15 amps would be better served by Tyco AMP superseals available in single and multiple connectors

I suggest you don't use multiple connectors, or make 'wiring loom' type bundles of wires; it is a nightmare locating faults. (Ie: cars and motorbike looms)

Much better to makes an individual descreet connection for each wire, then it's easy to disconnect and test individually for faults. Faults in multiple connectors are a total disaster.......

My suggestion is to bundle each set of specific wires together, and locate them in their own opening cable hook, and don't bundle them into trunking.
 
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The idea of superseals is to prevent faults occurring in the first place!

Iveco, Cummins, Merc, MAN, Scania, Optare, Dennis use precisely the fitting types and trunking mentioned for engine harnesses and chassis looms. Gone are the days of wrapping tape round a bundle of wires in heavy duty applications.

Or does the forum know something they don't?

Still not getting into an argument, everyone has the right an opinion and I stand by mine. Properly specified, supported and protected wiring systems will not fail without extreme provocation.
 
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