TDI unplugged conversion?

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MacWilliam
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TDI unplugged conversion?

Post by MacWilliam »

I am a bit puzzled here. Can anybody help? Can a TDI run without all the electronics? After all the older engines did and they were similar. For instance in the unlikely event that my newly fitted AAZ gives up the ghost, could I fit a Tdi with my manual injection pump etc? :?

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Post by Diamond Hell »

No, TDIs need their electronics. That's kinda like asking 'my carb engine runs fine without any electronics, surely I can take all of the electronics off a modern petrol injection engine and it'll be fine?'

You'll needd a mechanical injection pump that's matched to the engine. Central VW on the Wirral can supply these. Russel at Syncronutz is getting one shortly and I know of one other on the IOW which the guy is pleased as punch with.

Alternatively go get one from Bernd Jaeger in Germany - a snip at 2800 Euros.

It's either that or start wiring.
Diamond Hell
Still Syncro, just much fasterer

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MacWilliam
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Post by MacWilliam »

Thanks again Diamond Hell. So it is possible in a way but costly. Hmmm considering i bought the aaz for £ 170 odd it probably aint worth it at this point in time.

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Post by Russel »

The pump i am waiting for is supplyed by central but not manurefactured by them.That is kept confidential.
U need to use different injectors to get better power though.These come in at £97.40 + vat + a surecharge of £70 each times four OUCH.These injectors were not fitted to any vehicles in the UK only Europe.So the surecharge may be demanded from u.
The pump comes in at close to the £800 mark.
Personaly if i were looking at a TDI for a 2WD not syncro i would stick with the fly by wire.
The only reason i am going mechanical is because this is an expadition vehicle.

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Post by Simon Baxter »

I run a mechanically injected TDI, or I did until I killed it!
Too much buggering with boost pressure I fear! :lol:
People have fitted AAZ pumps and other IDI pumps to a TDI with limited success, it's not right, it works to some extent but it's not right, the pressures that a IDI pump will produce is half that of what a TDI requires.
You have a few choices.

Fit the electronics.
Buy a pump already done (Berndt Jaeger)
Build a pump.

Building a pump is expensive seeing as there wasn't one anyway, no one has a spec sheet as to what to build one to or set it up like.

I have had one built, you can happily have the specs, to build mine I needed parts from 4 different pumps, there is ONE pump out there that is like rocking horse sh!t (non VW) anway that would work with only the swapping of the throttle linkages and the cam plate but theres no cars on the road nevermind in the scrappers.

Spec of my pump

20mm driveshaft and pump
11mm head and rotor.
Ford Escort 1.6 Diesel case.
TDi Cam plate
JX governer housing (Pump top)

You need a 20mm driveshaft and pump because the TDI needs to operate around 1000bar, a IDI pump (17mm driveshaft) can only deliver half this.

running a AAZ/SB/RA pump will mean white/blue smoke (cool combustion temperatures) due to the fuel not being atomised properly and you will have to to "max out" the fuel screw to get it to perform anywhere near properly, then you run the risk of the driveshaft shearing due to the extreme pressures (hence 20mm driveshaft)

Been there, done that sort of thing.

People keep asking me to sell my pump or get more made but it's really not worth me doing it as I have to put some sort of warranty on what I do, and with these hybrid pumps you can't do that.

To build your own you will need to but 4 pumps (expensive) then get someone to do the work (expensive) then you run the risk of it not working.

If I were to do it again I would do it electronically or buy a pump from mr Jaeger.
'86 VW T3 syncro panel
'89 VW T3 Westy Atlantic
'81 Porsche 924
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Post by andyel »

Doing away with the electronics of a TDI in my opinion defeats the object of fitting one.
The ECU has many functions a mechanical pump cannot provide alone.
eg, anti jerk damping, helps setoff from standstill,smooth running control,improves idle etc.
You could also gain an immobliser,depending how you tackle it.

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Post by Russel »

These things are all true but when u are 5000miles from the nearest euman(not vilage)in the sahara then my faith is in the simplisity of a mecanical pump with no electronics attatched.
The reason for using the TDI is the enourmouse increase in talk compared to any other given engine.
As i have said if i fitt a TDI to any other vehicle(not syncro)then i would stick to the original setup.

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Post by Simon Baxter »

andyel wrote:Doing away with the electronics of a TDI in my opinion defeats the object of fitting one.
The ECU has many functions a mechanical pump cannot provide alone.
eg, anti jerk damping, helps setoff from standstill,smooth running control,improves idle etc.
You could also gain an immobliser,depending how you tackle it.

I bought a cheap engine with no ECU etc, that was my only option.
Drag racing TDI's have mechanical pumps, bit like fitting fourties to a petrol engine, not as precise as injection but ultimatley more tuneable.
'86 VW T3 syncro panel
'89 VW T3 Westy Atlantic
'81 Porsche 924
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Post by andyel »

I agree with you both in the situations you quote.
I wouldnt want to be stranded in the middle of nowhere with a complex electronic problem.
Or limited to the fueling map intended for a standard motor when building a competition engine.
But for a road going camper for instance,which will not be up to its axles in muddy water,using the whole TDI package would give a pleasant drive with easy reliable starting.
Good luck on your planned overseas trip Russel.
A real test for any 4by4.
caution- anything preceding this could be pure fantasy or just lies.The voices made me do it.
Andy

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MacWilliam
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Post by MacWilliam »

andyel wrote: Good luck on your planned overseas trip Russel.
A real test for any 4by4.

Oh! I thought he was just planning a trip to central Glasgow :D

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Post by Russel »

Ill probanbly go to central Glasgow less than i would the sahara. :lol:
I fitted a 90bhp TDI to my last mud toy(syncro)with all electronics etc.
I found it to be a pleashure to drive on and off road.The talk was perfect and economy good.The electronics had a few problems when off roading
caused by water in conections but was always just a blow out and on ure way.In future on the TDI's i will not have any plugs in engine bay to solve this.

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Post by Diamond Hell »

Here's a large bucket of water to throw over your electronics, oh and here's some silt and here's a big bag of sand.... and some organic matter thrown in.... and some poo.

Now how's your electronics?

:wink:
Diamond Hell
Still Syncro, just much fasterer

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