The Ford to Cummins Conversion Thread

Probably no use to you at all, but i work on daf trucks and we havent seen any of the old cummins 6 pot for a good while now, always made me smile when driving them, revved like the clappers and just kept on revving, always seemed to suffer from oil leaks on the timing chest cover and the rocker cover gaskets were consumables, cant say i remember seeing one in bits, unlike the later common rail ones!
The dipstick was up by the back left hand side of the cab hence the length of the thing.


Lynall
 
Right then...I think the bell housing bolt pattern outer is SAE1, need Latestarter to confirm, I had a spare pair that I could have used as a pattern but sold them to Latestarter, the inner BW bolt pattern I have got in the BW manual. Let's see what LS thinks of this idea then I'll set my chum to work on the CAD.

The radius..where your side extension flaps are, you've got a 90 deg corner, would be better to put a bi radius in there to take away the stress point.

If you are going from Fords to Cummins, you know you can use the Perkins 6.354 adapter plate.
 
Right then...I think the bell housing bolt pattern outer is SAE1, need Latestarter to confirm, I had a spare pair that I could have used as a pattern but sold them to Latestarter, the inner BW bolt pattern I have got in the BW manual. Let's see what LS thinks of this idea then I'll set my chum to work on the CAD.

The radius..where your side extension flaps are, you've got a 90 deg corner, would be better to put a bi radius in there to take away the stress point.

If you are going from Fords to Cummins, you know you can use the Perkins 6.354 adapter plate.

I have no issue with rear mounting off adaptor plate, I just prefer using gearbox, however your plan to use laser cut adapter plate with 'ears' is nice particularly the slotted holes for adjustment.

Flywheel housing is SAE 3 not SAE 1 will dig out drawing with dimensions to post on the website, turning it into CAD file with BW pattern would be nice, particularly as some ZF boxes share the SAE BW hole pattern.

Going back to oil pan question by OP, Cummins offered the EXACT steel sump as option in 1986 and dropped it shortly afterwards for marine propulsion when the alloy pan was introduced, my only reservation that sticks in my mind is a possible installation limitation, however I will dig out the drawing for you. Marine auxiliary units still use the steel pan, the 6BT bow thruster engines I used to survey have steel pans.

OP was very lucky to get breaker to leave the complete DAF dip stick with the engine, normally gets chopped off. When you have decided what length you require cut the plastic tube to length, use Stanley knife to cut alloy ferrule free. Cut down dip stick so it is just touching bottom of the pan, warm up plastic tube with heat gun and insert ferrule into tube. Put a blob of braze on the end of the dipstick so it does not catch on the way down. Only once engine is installed and vessel afloat calibrate the dip stick, fill the lube filter and add nine liters of oil to the pan. Run the motor for a short time and allow to settle for a quarter of an hour. Insert dip stick and mark, this is your low mark, put another liter of oil in the pan, allow to settle, re-insert the stick, you now have our high mark.

Do not use a hacksaw to mark the stick, use an engraver.

Good luck
 
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Probably no use to you at all, but i work on daf trucks and we havent seen any of the old cummins 6 pot for a good while now, always made me smile when driving them, revved like the clappers and just kept on revving, always seemed to suffer from oil leaks on the timing chest cover and the rocker cover gaskets were consumables, cant say i remember seeing one in bits, unlike the later common rail ones!
The dipstick was up by the back left hand side of the cab hence the length of the thing.


Lynall

It's of a lot of use, thanks. I'm amazed how many folk have firsthand experience of this engine - and all seem to rate them highly.

If you come across an old DAF engine with the same spec as mine up for grabs - please do drop me a PM.
 
Right then...I think the bell housing bolt pattern outer is SAE1, need Latestarter to confirm, I had a spare pair that I could have used as a pattern but sold them to Latestarter, the inner BW bolt pattern I have got in the BW manual. Let's see what LS thinks of this idea then I'll set my chum to work on the CAD.

The radius..where your side extension flaps are, you've got a 90 deg corner, would be better to put a bi radius in there to take away the stress point.

If you are going from Fords to Cummins, you know you can use the Perkins 6.354 adapter plate.

Yes, CAS drafting shouldn't be too much of a problem. I've got the luxury of both engine and gearbox close to hand, so I can make a full scale paper mock-up to check no serious errors haven't been made. Before going down this route, I'm going to wait until I've got the old engines out, then I'll be keeping the 'new' engine in the boat for the time being, resting on one of the engine beds so I can get a better idea of how it's going to work. I'll be stripping out the empty side of the engine bay, repainting, flowcoating, while the gunky new engine sits on the gunky side of the engine compartment.

LS mentioned about the Perkins adapter plates, but the problem is finding two old ones!

Ahh, yes, good point re stress point (early airliners crashing, etc). Here's my Mk II, complete with (drum roll!) an integral gearbox oil cooler mounting plate...

AdapterPlateIdeaMkII.png
 
Going back to oil pan question by OP, Cummins offered the EXACT steel sump as option in 1986 and dropped it shortly afterwards for marine propulsion when the alloy pan was introduced, my only reservation that sticks in my mind is a possible installation limitation, however I will dig out the drawing for you. Marine auxiliary units still use the steel pan, the 6BT bow thruster engines I used to survey have steel pans.

Thanks, LS. Here’s a rough and ready same-scale superimposition of three Cummins 5.9 (in red) with a steel shallow+deep sumps over three of my existing Ford Dorset/Dover (in blue) which also has a shallow+deep sump.

FordCumminsSumpDiagram.png


It’s quite a mess, as the diagrams also featured the flat sumps as options in the same diagrams. These are only brochure diagrams taken from old Thornycroft and Sabre sales material, but it seems to give a reasonable indication as to eventual clearance.

Here are the accompanying images and data for Thornycroft’s Cummins 5.9-based range from, at a guess, the mid-80's (why weren’t these Thornycrofts more successful? I’ve only ever seen one in LS’s workshop)…

ThornycroftBrochure1.jpg


ThornycroftBrochure2.jpg


ThornycroftBrochure3.jpg


They seem to allow for an installation of 12º plus 3º rise when underway. I need to double-check my engine’s installation angles.

I wondered if Thornycroft used any special oil pickups?
 
OP was very lucky to get breaker to leave the complete DAF dip stick with the engine, normally gets chopped off. When you have decided what length you require cut the plastic tube to length, use Stanley knife to cut alloy ferrule free. Cut down dip stick so it is just touching bottom of the pan, warm up plastic tube with heat gun and insert ferrule into tube. Put a blob of braze on the end of the dipstick so it does not catch on the way down. Only once engine is installed and vessel afloat calibrate the dip stick, fill the lube filter and add nine liters of oil to the pan. Run the motor for a short time and allow to settle for a quarter of an hour. Insert dip stick and mark, this is your low mark, put another liter of oil in the pan, allow to settle, re-insert the stick, you now have our high mark.

Do not use a hacksaw to mark the stick, use an engraver.

Fantastic, thanks. That sounds like a simple, doable and enjoyable little project. Imagine if I over-oiled and this happened within the confines of a my boat... http://www.youtube.com/watch?v=d_8Fc9qAZcw
 
It's of a lot of use, thanks. I'm amazed how many folk have firsthand experience of this engine - and all seem to rate them highly.

If you come across an old DAF engine with the same spec as mine up for grabs - please do drop me a PM.

Mate used to work at a place that used to break trucks out the back of Paddock Wood called CMS i think!
Might be worth a call?
Other place is Ryder truck sales Strood depot, they have all sorts of weird and wonderful stuff hanging around, including im sure some old 45 models which is what you need, they have a yard next to us with approx 50/100 trucks in and some of them have never moved in the six years i have worked there.
Quite a few fitted to land rovers as well, look on youtube.


Lynall
 
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Mate used to work at a place that used to break trucks out the back of Paddock Wood called CMS i think!
Might be worth a call?
Other place is Ryder truck sales Strood depot, they have all sorts of weird and wonderful stuff hanging around, including im sure some old 45 models which is what you need, they have a yard next to us with approx 50/100 trucks in and some of them have never moved in the six years i have worked there.
Quite a few fitted to land rovers as well, look on youtube.

Thanks, I'll bear them in mind.

If there was room in my Series 1's engine bay I probably would!
 
Ah in thats case you need a 200tdi got one in my s2 transformed it, was originally the very early naturally aspirated 2.0 litre diesel!



Lynall
 


I perceive something that will need to be addressed, the thickness of this plate will adversly effect the engagement of the gearbox input shaft into the drive plate, 8mm thickness = 8mm less engagement, shouldn't be to hard to deal with, either by specifying a drive plate spacer or a different thickness of drive plate.
 
I perceive something that will need to be addressed, the thickness of this plate will adversly effect the engagement of the gearbox input shaft into the drive plate, 8mm thickness = 8mm less engagement, shouldn't be to hard to deal with, either by specifying a drive plate spacer or a different thickness of drive plate.

Ah - should have said - I thought up 8mm purely off the top of my head! I want it to be as thin as possible, without compromising integrity obviously.
 
Ah - should have said - I thought up 8mm purely off the top of my head! I want it to be as thin as possible, without compromising integrity obviously.

Oh, interesting, I thought 8mm sounded a bit light and maybe 10mm would be better.

Thinking a bit more, does the adapter plate have a register ring that locates in the bell housing? We need to make sure that the BW input shaft is properly concentric with the crank.

LS care to comment?
 
Thinking a bit more, does the adapter plate have a register ring that locates in the bell housing? We need to make sure that the BW input shaft is properly concentric with the crank.

Do you mean some kind of continuous lip protruding into the bell housing all the way around to assist with precise locating? Would this be needed if all the bolt holes were in the right place?

Here's the current Ford adapter plate, which uses two steel dowels:

FordAdapterPlateLocatingPins.jpg
 
The issue Ben is alluding to is lack of spline engagement.

If you use a R&D 48AD5 adapter plate mated to the standard SAE automotive flywheel measure with care. Conventional wisdom is to machine a register in the flywheel to center the drive plate. The R&D drive plate has holes which are merely punched and whilst OK for securing are poor for accurate location. However too deep a register robs you of spline engagement depth.

Better to mount R&D drive plate on the face of the flywheel and drill to take locating dowels, the existing hardened dowels which located the automotive clutch put up a fight but do come out and you can use these. All a bit of a fag to set up in the lathe as you need to take a light cut off the flywheel face to clear the large rivets which secure the damping element to the plate before it will sit dead flush with the flywheel face.

A Vulcan coupling gives greater scope for spline engagement however is three times the price of the R&D so worth persevering.

Finish off by securing drive plate to flywheel with high tensile fasteners, 10 mm black cap heads are good with a dose of Loctite. B is a far more spunky motor than than the Fords and the extra torque needs treating with respect.

good luck
 
Here are the accompanying images and data for Thornycroft’s Cummins 5.9-based range from, at a guess, the mid-80's (why weren’t these Thornycrofts more successful? I’ve only ever seen one in LS’s workshop)
They seem to allow for an installation of 12º plus 3º rise when underway. I need to double-check my engine’s installation angles.

I wondered if Thornycroft used any special oil pickups?

The Thornycroft deal came about in a real complex way..................Are you ready for this??

British Leyland truck division obtained a licence to produce the B Series at their Bathgate plant in Scotland to replace the 4/98 and 69/98 engine range. BL owned Thornycroft as well as latterly producing their own Leyland marine engines based on the 98 Series engines in competition with Thornycroft, no wonder the group lost shed loads of $$

Cummins Darlington was producing the dreaded small V motor at the time which was a Chrysler Cummins JV.

Bathgate was a modern truck plant but riddled with industrial strife. Original plan was for BL to build base motors for their own truck production, known as the 300 Series and some limited applications one being Thornycroft. Industrial/tractor applications would come out of the Case B Series plant in Noyce Germany.

At the last minute BL imploded, the industrial unrest at Bathgate was unsustainable and funding for a new factory at Leyland called the LAP (Leyland Assembly plant) was granted conditional on the closure of troublesome Bathgate.

In the same timescale Chrysler was losing $$ on commercial vehicle production and sold out to Renault, Cummins purchased the Chrysler share of Darlington. The small V production line was shipped to Mexico and the production line intended for Bathgate went into Darlington which became supplier of Leyland LAP branded Leyland 300. Thornycroft was already planning to marinise the Leyland 300 out of Bathgate and Cummins saw no need to start production of US marinised B Series engine at Darlington once production of V8 504 and V8 555 ended.

Thornycroft had a sound dealer network and good reputation, however BL sold out to management, and from there matters began to deteriorate. Cash strapped Thornycroft was purchasing base engines out of Darlington without warranty which they were not allowed to alter and all went very well at the beginning.

The **** hit the fan in export markets where the Cummins brand was far stronger than Thornycroft, owners looked to Cummins distributors for support and were shocked to find that engines had no Cummins warranty.

Then another factor came into play, B can be a bitch to de-airate and the Thornycroft marinisation was under developed in this area. Many engines failed on the Thornycroft dyno due to overheating and were re-built by Cummins distribution network before being sold. Several owners suffered failures and discovered that engines had already been rebuilt when they had purchased them as 'new'. When Cummins UK discovered what was going on they terminated the supply agreement with Thornycroft and supplied new replacement engines to placate customers. Thornycroft with no key engine supplier went to the wall......

As stated Thornycroft not permitted to alter base motor, 15 degrees is acceptable PROVIDED turbo can drain properly and engine cooling system de-airate properly. Lancing conversions do NOT meet this criteria.

Hope this helps..
 
The issue Ben is alluding to is lack of spline engagement.

If you use a R&D 48AD5 adapter plate mated to the standard SAE automotive flywheel measure with care. Conventional wisdom is to machine a register in the flywheel to center the drive plate. The R&D drive plate has holes which are merely punched and whilst OK for securing are poor for accurate location. However too deep a register robs you of spline engagement depth.

Better to mount R&D drive plate on the face of the flywheel and drill to take locating dowels, the existing hardened dowels which located the automotive clutch put up a fight but do come out and you can use these. All a bit of a fag to set up in the lathe as you need to take a light cut off the flywheel face to clear the large rivets which secure the damping element to the plate before it will sit dead flush with the flywheel face.

A Vulcan coupling gives greater scope for spline engagement however is three times the price of the R&D so worth persevering.

Finish off by securing drive plate to flywheel with high tensile fasteners, 10 mm black cap heads are good with a dose of Loctite. B is a far more spunky motor than than the Fords and the extra torque needs treating with respect.

good luck

An amazing insight, Paul, thanks.

When you say 48AD5 adapter plate – I take it you meant drive plate?

Shamefully, I didn’t know what machining a register meant, but I now understand it to mean putting something with a flat surface onto a the lathe and cutting out a disk shape, or leaving a disk shape standing proud, so that something else can fit onto or into the machined item to locate it centrally, or just provide room.

Here are current drive plates, which I’m assuming will be okay to use with the Cummins:

DrivePlate3.jpg


DrivePlate2.jpg


They were bolted to the flat surface of the flywheel, with that part of the drive plate holding the springs pointing towards the gearbox like so:

DrivePlate1.jpg


OldFlywheel.jpg


I think a lot of this will become clearer once I put the ‘new’ Cummins onto one of the old beds for the time being, then I can play with all the parts in close proximity.
 
The Thornycroft deal came about in a real complex way..................Are you ready for this??

British Leyland truck division obtained a licence to produce the B Series at their Bathgate plant in Scotland to replace the 4/98 and 69/98 engine range. BL owned Thornycroft as well as latterly producing their own Leyland marine engines based on the 98 Series engines in competition with Thornycroft, no wonder the group lost shed loads of $$

Cummins Darlington was producing the dreaded small V motor at the time which was a Chrysler Cummins JV.

Bathgate was a modern truck plant but riddled with industrial strife. Original plan was for BL to build base motors for their own truck production, known as the 300 Series and some limited applications one being Thornycroft. Industrial/tractor applications would come out of the Case B Series plant in Noyce Germany.

At the last minute BL imploded, the industrial unrest at Bathgate was unsustainable and funding for a new factory at Leyland called the LAP (Leyland Assembly plant) was granted conditional on the closure of troublesome Bathgate.

In the same timescale Chrysler was losing $$ on commercial vehicle production and sold out to Renault, Cummins purchased the Chrysler share of Darlington. The small V production line was shipped to Mexico and the production line intended for Bathgate went into Darlington which became supplier of Leyland LAP branded Leyland 300. Thornycroft was already planning to marinise the Leyland 300 out of Bathgate and Cummins saw no need to start production of US marinised B Series engine at Darlington once production of V8 504 and V8 555 ended.

Thornycroft had a sound dealer network and good reputation, however BL sold out to management, and from there matters began to deteriorate. Cash strapped Thornycroft was purchasing base engines out of Darlington without warranty which they were not allowed to alter and all went very well at the beginning.

The **** hit the fan in export markets where the Cummins brand was far stronger than Thornycroft, owners looked to Cummins distributors for support and were shocked to find that engines had no Cummins warranty.

Yes, Paul, thanks – it really does help to understand a little of the politics. It’s easy to think – from the relatively ignorant punter’s point of view, that new engines for sale have been designed, developed and produced by people with near-perfect knowledge.

Amazing to think that while BL owned Thornycroft, they were selling Ford-based units alongside, with very similar stats – even in the same brochure!

Then another factor came into play, B can be a bitch to de-airate and the Thornycroft marinisation was under developed in this area. Many engines failed on the Thornycroft dyno due to overheating and were re-built by Cummins distribution network before being sold. Several owners suffered failures and discovered that engines had already been rebuilt when they had purchased them as 'new'. When Cummins UK discovered what was going on they terminated the supply agreement with Thornycroft and supplied new replacement engines to placate customers. Thornycroft with no key engine supplier went to the wall......

I hadn’t realised that de-airation was such an important issue. Did you have to alter the Thornycroft-Cummins much you had in your workshop a couple of year back?

As stated Thornycroft not permitted to alter base motor, 15 degrees is acceptable PROVIDED turbo can drain properly and engine cooling system de-airate properly. Lancing conversions do NOT meet this criteria.

Hence (?) your cunning modification of Bowman’s CM600 water-cooled manifold-cum-header tank. I can keep the same oil pick-up, then, and in fact keep the bottom half of the engine as-is?

ManifoldMod1.jpg


ManifoldMod2.jpg
 
An amazing insight, Paul, thanks.

When you say 48AD5 adapter plate – I take it you meant drive plate?

Shamefully, I didn’t know what machining a register meant, but I now understand it to mean putting something with a flat surface onto a the lathe and cutting out a disk shape, or leaving a disk shape standing proud, so that something else can fit onto or into the machined item to locate it centrally, or just provide room.

Here are current drive plates, which I’m assuming will be okay to use with the Cummins.

They were bolted to the flat surface of the flywheel, with that part of the drive plate holding the springs pointing towards the gearbox like so:




I think a lot of this will become clearer once I put the ‘new’ Cummins onto one of the old beds for the time being, then I can play with all the parts in close proximity.

Very old Borg & Beck drive plates I think. If you intended using on a planing vessel I would say no, as B torque will soon hammer springs loose, however you will not be giving motor loadsa tight wire to get over the hump you will likely get away with the old drive plates, sure sign of impending failure will be a death rattle at idle.

Note the B in the Fairey Huntress you went out on, he loves to give it armfulls of throttle.
 
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