JX to AHU 1Z MTDI engine conversion, what do I need

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syncro garry
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JX to AHU 1Z MTDI engine conversion, what do I need

Post by syncro garry »

Hi
My 1.6 td JX engine (fitted with intercooler) in my 1990 Syncro has died.
These are my only wheels so want to get back on the road ASAP 
 
I am looking to replace it with a 1.9 TDI AHU (the same block as a 1Z) engine & fit a mechanical fuel pump.
I have the option of a not so good complete engine or a reconditioned long block.
My priority is reliability but a small power increase would be welcome.
If I go for the long block I know I would also need to fit the intake manifold & oil breather to block pipe (I hope to keep the JX exhaust manifold & turbo to allow me to use the original 1.6 engine brackets).
 
My question is; is it possible for me to use the other ancillaries (alternator, PS pump etc) for ease of fitting & am I missing anything???

davidoft1
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Re: JX to AHU 1Z MTDI engine conversion, what do I need

Post by davidoft1 »

If you buy a new long block you will need injectors, fuel pump either modified or replaced with appropriate stuff , the rest should be plug n play

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ZsZ
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Re: JX to AHU 1Z MTDI engine conversion, what do I need

Post by ZsZ »

You need the tdi longblock with injectors, tdi vacuum pump, tdi water pump and tdi injector hardlines.
All other thing can be used from the JX except the injection pump. The JX oil pump can be good if it has 36mm tall gears but swap the pickup to the tdi when it has only 30mm tall gears.
The ports wont match fully on the intake, you will have to use the JX mounting studs of the alternator bracket and there is a possibility to the clutch to slip with a worn JX plate (then do a kevlar fibre strengthened friction surface update)
I ran my 1Z with a Fiat Croma pump like this for over 10 years. Since that I ported the intake, changed the turbo to an AAZ one and I use a 225mm 1Z solid flywheel clutch and had a custom pump made with 502 injectors.
And use a transverse tdi engine as the passat ones need custom engine mount.
Zoltan
1986 Multivan ex-Caravelle. Van since 2006, running mTDi 1Z since 2008 with Fiat Croma 1.9 TDid pump 2008-2019, custom pump since 2019
5spd custom box 4.57 diff + 0.74 5th

syncro garry
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Location: Golden, BC, Canada

Re: JX to AHU 1Z MTDI engine conversion, what do I need

Post by syncro garry »

Thanks for the info.
I plan to get new  injectors. glow plugs, clutch, oil & water pumps for reliability while the engine is out & fit the JX oil sump & pick up tube.
Will the AHU flywheel & clutch fit in the diesel bell housing or will I need the JX pressure plate?
My clutch is the later hydraulic one.
The hoze connector with temperature sensor fitting on it looks as if it might contact No 4 injector on the side of the cylinder head will I need the AHU pipe fitting?
Sorry to be a pain but I am trying to work out everything I need before starting as I live in Canada & things ordered online can take weeks to get here.
 

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Aidan
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Re: JX to AHU 1Z MTDI engine conversion, what do I need

Post by Aidan »

The AHU flywheel fits inside the bellhousing , though I'd recommend going to a dual mass flywheel to the gearbox cope better with the new engine. If you use the AHU one then you'll need to do a hybrid clutch using the WBX friction plate which matches the splines on the gearbox input shaft, or change the input shaft to the TDi splined version to enable use of TDi Golf4 etc friction plate or the dual mass flywheel/clutch
Be aware the TDi engine is a bit rev limited compared to the TD so fine for general use but if you want to do a lot of long distance motorway work in a hurry then you'll be looking at changing the gearing.
Change the gearbox oil regularly the box is going to have a harder time with the new engine

davidoft1
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Re: JX to AHU 1Z MTDI engine conversion, what do I need

Post by davidoft1 »

you will be better buying a complete 2nd hand engine to rebuild, the pump and injectors will cost a lot if you need to buy them outright, as well as all the other little bits here and there you are likely to need

syncro garry
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Re: JX to AHU 1Z MTDI engine conversion, what do I need

Post by syncro garry »

Thanks Aidan
I don't know if you remember but you rebuilt my gearbox & front diff back in spring 2014.
It was the blue (Busman) 16" Syncro with 6.17 diff & you fitted 1.14 & 0.75 3rd & 4th for me as well as a new viscous.
I moved to BC Canada (with the van) 2.5 years ago & having the option of 2WD, 4WD or AWD makes this the most versatile vehicle around, esp in winter.
I am trying to get all my ducks in a row before starting the engine switch with the idea that I can tweak things in the summer.
Currently I don't have a workshop to play in so doing work outside with an average of 0 to -15C & 3ft of snow is testing.
I hope all is going well with you in these strange times.
Take care
Garry

 

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