Petrol to Diesel swapover

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Linegeist
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Petrol to Diesel swapover

Post by Linegeist »

Is it safe to assume that petrol and diesel models have all their opposite number's ancillary wiring and mounts in place for ease of manufacture, or are there serious structural, wiring and design differences?

The reason I ask is that my otherwise very tidy 1.6 petrol Athena has a dreadful, worn, agricultural and clattery engine/gearbox - and I have a very nice, low mileage 1.7 turbo diesel combo that could be slotted in its place.

Leaving aside the DVLA machinations that would result, it ought to leave me with a very nice car ................ if it's straightforward enough. Will I have to hardwire-in the glowplug circuitry for example, or is the cabling already there? I have a shedload of donor parts from a previous dead diesel (tank, rad, battery, H/D alternator, etc.

I have a reasonably equipped workshop with an engine hoist, welding gear, stands and stuff - and I was once a Motor Vehicle Technician in a previous life (that once shoehorned a V8 Rover into a Ford Cortina :shock: ). How feasible is this idea for a 1-week autumn project d'ye think? <crosses thumbs and hopes not to get flamed> :wink:
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mat_fenwick
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Post by mat_fenwick »

Would be very interested in the Rover V8/Cortina hybrid - I'm doing the same with a Hyundai Stellar (which is a Cortina under the skin anyway). How did you get the OS exhaust manifold round the steering column? I've build a manifold with 2 pipes above and 2 below, but I've had to modify the upper wishbone slightly...

If you answer my question then I may *think* about answering yours... :wink:
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Post by citronut »

it should just drop straight in Bob, all the moutting points are the same, and you can put you welder away, diferent down pipe, most of the rest is much the same,

regards malcolm
curent ride
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also own
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Post by Linegeist »

mat_fenwick wrote:How did you get the OS exhaust manifold round the steering column? I've build a manifold with 2 pipes above and 2 below, but I've had to modify the upper wishbone slightly...

If you answer my question then I may *think* about answering yours... :wink:

:lol: :lol:

IIRC, I fabricated a 3-piece articulated steering column that went around the engine - in any case, the front axle had to be moved forward by about 2" (from memory) to clear the sump pan, so the rack went with it. Once it was decided the steering column had to be lengthened, it was a small step to introducing another UJ and rotating the rack axially to give a different approach for the input shaft.

The hardest part was getting the front wheel arches to look right afterwards - finally achieved by simply cutting out the entire arch and welding it back on 2" further forward, then welding the cut-out section into the gap at the rear. This was before MIG, so it was a No1 Oxy/A nozzle, a handful of 1/16" rods, and lots of careful stitch-welding and panelbeating. :?

It didn't quite all match up as planned, but the magic of Isopon did its stuff and no-one was the wiser........... :oops:

citronut wrote:it should just drop straight in Bob, all the moutting points are the same, and you can put you welder away, diferent down pipe, most of the rest is much the same,

regards malcolm
Thanks for that Malcolm - I'd hoped that was the case, but my Colonel once described me as "A lightning rod, through whom many unpleasant things choose to discharge" :shock: In other words, if it's going to FUBAR, it'll FUBAR on MY watch! :cry: :lol: Knowing my luck, I'll have the only Athena, from a one-week special production run, where the engine mountings are reversed just because it was Bastille Day .......... :shock: :roll: :wink:
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Tim Leech
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Post by Tim Leech »

Bear in mind Bob that it will then be a modified car and may cause a problem, still think you shoud keep both and turn the radio up on the Athena, or get a decent 1.6 engine for it?
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Post by Linegeist »

Roverman wrote:Bear in mind Bob that it will then be a modified car and may cause a problem, still think you shoud keep both and turn the radio up on the Athena, or get a decent 1.6 engine for it?
Funnily enough guv', I spoke with the registration loonies and asked them what would be the situation if I re-shelled the TZD. "No need to worry" said they. "Just give us the new numbers". :o

So then I asked, "What if the new body's not an actual estate - but a hatchback?" There was a pause, before the nice chap on the other end (I suspect out of his depth) responded with, "It's not a mechanical or performance modification, like a different engine, is it? So I think it'll just be an odinary alteration to the registration document - same as a colour change after a respray. It'll still be essentially the same car" :shock:

So, I won't be swapping engines see? I'll be swapping BODIES! So, as far as the insurance company's concerned, it'll simply become a TZD/Athena.

This is why I'm checking on here among the real experts ............... :wink:
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Post by Tim Leech »

Shame to scrap the TZD, although im not a fan of the estate, most on here are, especially a TD powered one which is the perfetc practical classic, and its one less BX on the road!

Surely someone out there has an engine, either petrol or diesel.

I would be VERY wary with the DVLA, I have to suffer them regularly with my job and NOTHING is straight forward, you could end up with all kinds of red tape.
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Post by mat_fenwick »

To do an engine swap now, and get the numbers right on the V5 you need an independant 'report' to say the new engine is in the vehicle. With me it was sufficient to get a letter on headed paper from a garage stating this, which they kindly did gratis. I would imagine the same sort of thing would apply with a body swap...
I wouls have thought you'd need to swap quite a bit of wiring, but you'll have a donor vehicle next to you so should be a piece of cake. Driveshafts will need to be swapped too, as they are stronger on the TDs.
I don't know whether the petrols have a return fuel line like the diesels so something to watch for.
Regarding the question of whether it's the right thing to do - well, it's your car to do with as you choose. It may seem a waste to some, but arguably you'll be keeping a rarer vehicle on the road.

Back to the Cortina - rather drastic compared to what I've done! I've just done a cut and shut job on a Range Rover sump to clear the crossmember, and surprisingly it doesn't leak! :D I'm slightly worried by the lifespan of the steering UJ right next to the exhaust manifold, but
a) it's a way off being on the road
b) I'm not going to be doing shedloads of miles in it!
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Post by citronut »

the BX engine loom diesel/petrol un/plugs just under the battery, so i think the only other loom you will require is for the glow plugs/timmer,

regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)
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Post by Vanny »

I've done this far to many times, most recently diesel to petrol.

Because of Londoners re classing there cars to dodge congestion charges the DVLA have tightened up on what paper work is needed for fuel type changes. But you don't always need a specific report.

In my case i simply had the car MOT'd, the MOT man tested it as a petrol and hence i had proof that it was a petrol. Combined with paper work showing where the engine had come from, the fact that the donor car had been sorned, and a lovely picture of the donor car cut to pieces (that was just for fun :) ) the DVLA where perfectly happy with that.

As for the actual change, fuel pipes are a little different from petrol to diesel. Wiring differences as mentioned, the exhaust is very different, and the bonnet liner is also different. Quite frankly these are all fairly minor.

I've done the job in a single day before now (with a helper) so it must be straight forward.
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Post by mat_fenwick »

How recently was your last one Vanny? As I think the rules have changed in the last few years - certainly with the 1.9TD into the BX I sent them a photo of the donor car (SORNed), a photo of the engine half way out the donor car, halfway in the BX, in the BX with the engine number visible and that was still not enough, even though an increase of 136cc was obviously not going to reduce whatever charges I may pay so it would have been in my interest to keep it quiet! It could just be inconsistency within the DVLA I suppose?
They did however manage to fine me £80 for not chasing up their proof of my SORN declaration, not the first time either. :roll:
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Post by citronut »

the only prob with keeping it quiet is if you have a prang and your insurance get wind of the diferent lump in it they will void the policy,

regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)
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Post by Mike E (uk) »

I had a Cavalier which I owned for 17 years, until about 2 years ago.
After I had owned it for a few weeks, it got shunted.

The Car was reshelled, with everything except the boot lid swapped over onto the new body.

The car had no chassis number on it from then on.
I never told DVLA, and it never caused me a problem.

Don't know about any new DVLA rules though.

Mike
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Post by Linegeist »

I think I'll write formally to DVLA, asking for guidance on this. I don't trust the telephone chimps any more than I trust their SORN system or database.

If I have something in writing, which later turns out to be a load of old tosh, I at least have the fuel with which to roast some uninterested (un)civil servant's testicles. :twisted:

I have to say, the more I think about this, the more it appeals. The TZD break, while mechanically near-perfect, is a mess and needs a complete stripdown respray, plus new bumpers - and even then it's only a boring box on wheels with no sunroof, no spoiler and not much in the way of looks. The Athena's bodywork, on the other hand, is pretty mint and, coupled with the TZD's Engine, Recaros and trim, will make a rather nice top-end-of-the-range car with the relaxed turbodiesel legs to get places like Club meetings.

Once the Break bodyshell's stripped of its engine and trim, I can then consider my options - whether to put it in primer ready for later resurrection or cannibalise it for panel parts.
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Post by Vanny »

If you have a look on the Retro Rides forum there is a pretty lengthy thread on the matter.

Matt, i changed the engine type about 18 months/2 years ago, it was just after they started cracking down on the engine swaps. Previously I've simply sent int he log book with the changes and they have just accepted them.

The rules don't stipulate that it has to be a garage/dealer that confirms the change but some one who is technically competent, makes the options just that little bit greater. Perhaps you could fein a breakdown, get the AA out, make sure they fill in EVERYTHING on there form (fuel, engine etc) and post that to the DVLA.
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