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Author Topic: AHU MTDI in 81 Caddy quick question  (Read 4426 times)

June 05, 2014, 10:19:53 pm

Whitbread

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AHU MTDI in 81 Caddy quick question
« on: June 05, 2014, 10:19:53 pm »
Hey Guys, I've tried searching, but there's so much here it's hard to wade through in any sort of timely manner. Basically, I'm running a fully rebuilt AHU 2.0L TDI in my 81 rabbit truck as an MTDI. I built the pump and had it bench tested, passed with flying colors. I'm using the mk1 engine mount/accessory bracket. Issue I'm running into is the TDI high pressure fuel lines don't reach the pump in the MK1 location. Are there some magic lines people are using? Or just buying straight line from Rocken Tech and bending their own?

Other quick question is about the timing belt; I don't know squat about the IDI stuff so I won't pretend. Is the IDI belt strong enough to run the increased load of the DI pump now? Or should I cut the pump mount off the mk1 bracket and run the AHU injection pump bracket and timing belt setup? Is that the normal thing to do to kill 2 birds with one stone?

Thanks!

Here's some pics to show the line misalignment.



« Last Edit: June 05, 2014, 10:23:39 pm by Whitbread »


02 Jetta ALH TDI, 2260vk+02M
97 B4V ALH TDI, compound turbos + haldex awd
81 Caddy MTDI AHU
07 Arctic Cat 700 turbo diesel
90 Corrado ALH, 02M + haldex in progress
87 K10, Detroit 4-53T with twins
04 BEW going in 91 Ski Challenger boat

Reply #1June 05, 2014, 10:26:14 pm

theman53

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Re: AHU MTDI in 81 Caddy quick question
« Reply #1 on: June 05, 2014, 10:26:14 pm »
I think *don't know for sure* but you don't use the mk1 IP bracket, I think you only use the back 1/2 of it and use the ahu mount to actually mount the pump.

Reply #2June 05, 2014, 10:58:47 pm

libbydiesel

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Re: AHU MTDI in 81 Caddy quick question
« Reply #2 on: June 05, 2014, 10:58:47 pm »
The mk1 and AHU pump brackets mount the pump in the same place relative the injectors.  Are you sure those are AHU lines and not ALH?

Reply #3June 05, 2014, 11:23:54 pm

Whitbread

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Re: AHU MTDI in 81 Caddy quick question
« Reply #3 on: June 05, 2014, 11:23:54 pm »
The mk1 and AHU pump brackets mount the pump in the same place relative the injectors.  Are you sure those are AHU lines and not ALH?
D'OH! You called it. I easily have 10 sets of lines around my shop. Dug through my stash and found 4 odd balls. Wouldn't you know, they fit perfectly. I must've had ALH lines on there. Jackass moment of the night.



02 Jetta ALH TDI, 2260vk+02M
97 B4V ALH TDI, compound turbos + haldex awd
81 Caddy MTDI AHU
07 Arctic Cat 700 turbo diesel
90 Corrado ALH, 02M + haldex in progress
87 K10, Detroit 4-53T with twins
04 BEW going in 91 Ski Challenger boat

Reply #4June 06, 2014, 08:11:35 am

theman53

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Re: AHU MTDI in 81 Caddy quick question
« Reply #4 on: June 06, 2014, 08:11:35 am »
The mk1 and AHU pump brackets mount the pump in the same place relative the injectors.  Are you sure those are AHU lines and not ALH?
Great call. I didn't know but remembered some posts of how just the mount part was added. I should have looked at the lines better

Reply #5June 06, 2014, 09:22:27 am

GEE-BEE

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Re: AHU MTDI in 81 Caddy quick question
« Reply #5 on: June 06, 2014, 09:22:27 am »
I had classictube make a set for me in 304 seamless s/s

They do my landing gear hardlines for my aircraft brake kits

GB
1.9 AAZ, CHD 5spd with Peloquin
KO4/KO3 Hybrid turbo
Giles Pump OHC
Complete Techtonics 2'5 S/S DP and Exhaust
Coilovers, MKII Pedal Swap,G60 BRAKES
MK1 JETTA DASH
675MM 16V radiator (MKII) PASSAT DUAL FAN
42K original miles , South African Front End
15x6 Le Casletts 195-45-15

Reply #6June 06, 2014, 07:15:58 pm

Whitbread

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Re: AHU MTDI in 81 Caddy quick question
« Reply #6 on: June 06, 2014, 07:15:58 pm »
Now that we've all gotten a good laugh on me mixing up lines at midnight, what's the consensus on the 1.6 timing belt? Is it strong enough to run the mtdi pump without fear of breakage? Hell, even if I have to change it every 40-50k its only ~$30 and 10x easier than an alh.
02 Jetta ALH TDI, 2260vk+02M
97 B4V ALH TDI, compound turbos + haldex awd
81 Caddy MTDI AHU
07 Arctic Cat 700 turbo diesel
90 Corrado ALH, 02M + haldex in progress
87 K10, Detroit 4-53T with twins
04 BEW going in 91 Ski Challenger boat

Reply #7June 06, 2014, 07:23:38 pm

libbydiesel

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Re: AHU MTDI in 81 Caddy quick question
« Reply #7 on: June 06, 2014, 07:23:38 pm »
It's not the right length (1.9 has a taller block).  Use the AAZ/AHU belt.  It is the correct length, no harder to swap than the 1.6 belt and up to the task of running the mTDI pump without risk of breakage.

ALH is at least 10X harder.  Why did they wrap the engine mount?? 

Reply #8June 06, 2014, 07:55:41 pm

theman53

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Re: AHU MTDI in 81 Caddy quick question
« Reply #8 on: June 06, 2014, 07:55:41 pm »
I had classictube make a set for me in 304 seamless s/s

They do my landing gear hardlines for my aircraft brake kits

GB

How much did it cost you? The stock lines are a rip off new is why I ask and if stainless isn't much more or even less why run stock.

Libby, didn't they also use a small tensioner on some 1.9aaz and ahu so you could run the 1.6 belt? Again, I don't know for sure but I remember something of the sort being talked about.

Yes, ALH is horrible. Not only did they wrap the mount but the mount is Al so the bolts want to strip...when someone before you didn't support the engine and tried to bring it up with the bolts.

Reply #9June 06, 2014, 09:40:59 pm

libbydiesel

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Re: AHU MTDI in 81 Caddy quick question
« Reply #9 on: June 06, 2014, 09:40:59 pm »
Some early AAZ engines used the same tensioner as the 1.6 (068109243F) but even those early ones used the AAZ/AHU belt (028109119P). 

Reply #10June 23, 2014, 08:47:43 am

monomer

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Re: AHU MTDI in 81 Caddy quick question
« Reply #10 on: June 23, 2014, 08:47:43 am »
I had classictube make a set for me in 304 seamless s/s

They do my landing gear hardlines for my aircraft brake kits

GB

They haven't broken on you yet? SS likes to stress harden and it's tensile strength is lower than steel. Not what I would use for high pressure lines, attached to a Diesel....
-1983 Rabbit LX 1.6/1.9 VNT build


Michigan Volkswagen Enthusiasts
www.michiganvw.org

Reply #11June 23, 2014, 09:24:49 am

GEE-BEE

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304 S/S seamless
« Reply #11 on: June 23, 2014, 09:24:49 am »
We use them all day long on landing gear brake lines, flex hose on each end....

The key is seemless 304 spec

GB
« Last Edit: November 21, 2014, 08:32:10 pm by GEE-BEE »
1.9 AAZ, CHD 5spd with Peloquin
KO4/KO3 Hybrid turbo
Giles Pump OHC
Complete Techtonics 2'5 S/S DP and Exhaust
Coilovers, MKII Pedal Swap,G60 BRAKES
MK1 JETTA DASH
675MM 16V radiator (MKII) PASSAT DUAL FAN
42K original miles , South African Front End
15x6 Le Casletts 195-45-15