JX diesel injector pump boost device

[Bermoco]

Hello,
I recently bought a 1982 Westfalia Vanagon camper with a JX motor that was not running. Tried to start it and it acted like it wanted to start but would not stay running. I bypassed the fuel system with an alternate fuel supply. Used an outboard motor hose with primer bulb placed into a 1 gallon fuel can and plumbed directly to the injector pump. Squeezed the bulb until firm then cranked engine over and it took a little while but it started to run and finally idle.

Found that the fuel was contaminated with gasoline. Drained all the fuel out, replaced with clean diesel and changed the fuel filter and now the van is running quite well but seems to have low power. I realize that the diesels of that era were some of the most gutless VWs but the later JX motors that are turbocharged were much better.

I think I have two problems. 1) Low turbo boost 2) The fuel injection pump boost enrichment device diaphragm may be leaking.

I believe that the max boost from these turbos is .64-.76 bar which equates to 9.3 to 11 psi. I used a fuel pressure vacuum gauge and the max reading I got was somewhat close to 5 psi.

I also observed that the LDA on the injection pump moved very little. I applied air pressure with my mouth on the hose (yes I can hear you all snickering but it works !) leading to the actuator and it seems like it would bleed off as though the diaphragm leaked.

I read where someone used an inner tube to repair theirs but I would like to replace mine or have it rebuilt. Does any one provide this service?

Am reading through several threads but it seems like most posts are for rebuilding the JX motor.

Thank you in advance. This is a great resource.

[Alaskaberrys]

Hey Bermoco - I’m afraid I’m not much help on the LDA device, I just learned the name of it from MsTaboo a day or so ago. I’ve got the JX pump on an AAZ transplant.

Do you have a picture of what the other end of the line connects too? Mine is not attached to anything but has been that way since I started driving it just a few months back.

Hopefully someone will chime in on diagnostics and repairs on for it.

Mark
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'91 Westfalia, Bordeaux Red Pearl 2.1L 2wd Auto
'91 T3 Syncro Doka, Escorial Green 1.9L TD AAZ “Gremian” (to provoke, irritate, exasperate, vex...)

[Bermoco]

Hello Alaskaberrys,

I don't have a good picture of the other end but it attaches to the intake manifold. This hose is where I Teed of to measure the boost. As you probably know the intake manifold is not under vacuum like other normally aspirated engines but is under boost pressure. The LDA boost enrichment device works off of the manifold pressure to add more fuel under boost.

Since I posted this I began thinking about this device is like a vacuum advance canister on a distributor and have seen where people have replaced the diaphragm material. I may try this but if I can find a new or serviceable one for a reasonable price I would rather just swap it out. Hoping others will share their experiences.

How does your AAZ run? I would imagine it will run better with the LDA hooked up.

[Gnarlodious]

Boost pressure is a direct result of burned fuel. Thus you cannot get boost unless you have loaded the engine. Put a video camera back there and go for a drive, or have someone watch with the lid off, to get a real idea of the aneroid working. As I understand it, you may not see full boost pressure until the engine is hitting 3,000RPM at full fueling up a long hill.

Check the linkage of your aneroid and make sure the rod is free and working normally. A lot of things can affect the turbo engine. Turbo can be worn out or in the process of self-destructing. I suggest taking the hose off and feel with your finger the free play in the rotor. If it has radial motion, don't run it until you get a thorough evaluation or a rebuild. If it chews itself up you are stuck with buying a turbo, and that gets expensive.

You can also have excessively rich injection, a clogged or leaky wastegate valve, intake manifold coked up or any number of problems with an old engine.
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Vanagon ’83 diesel AAZ w/Giles injection, 5spd 4.57R&P+TBD and a '78 diesel Rabbit

[Zeitgeist 13]

I highly recommend anyone with a turbodiesel get a dual pressure/vacuum test tool like the Mityvac MV8510

This allows you to test your LDA and wastegate actuator, as well as a whole bunch of other functions. By applying an incrementally indicated amount of pressure you can see whether and when the actuators are moving. I use my much older version of this tool all the time.
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Casey--

'89 Bluestar ALH w/12mm Waldo pump, PP764 and GT2052
'01 Weekender --> full camper
y u rune klassik?

[randolph57]

LDA cannisters are well known for being defective(leaky) but from memory you should also first be checking the BOV (blow off valve) mounted on the end of the inlet manifold.
Some people have done away with the spring for a small piece of pipe which physically keeps the valve shut preventing any of the boost pressure escaping thus keeping the few remaining ponies within the engine.

[Alaskaberrys]

[Bermoco]

Hello All,
Thanks Gnarlodious,Zeitgeist, and Randolph 57 for your inputs and advice.
I had a chance to work on the diesel Vanagon with the JX motor. I inserted my pressure gauge tapped into the boost line from the manifold to the LDA boost enrichment device and also filmed the LDA with my Iphone set up in the back camper closet door shelf. (was a bit apprehensive about phone vibrating out of cabinet and falling through the engine compartment onto roadway but worked fine with no issues)Went for a ride and climbed some minor hills. Found that the turbo is putting out the required boost but the LDA canister not actuating the fuel boost properly. Guess I will have to repair or replace. I need those 12 extra ponies!
First picture is of the LDA with no boost. Second picture with red circle shows the slight displacement under boost but nowhere near max travel to the stop circled in red. Anyone have experience with how far the LDA should travel?
I have the Mighty Vac on the way as Zeitgeist suggested.

[ALIKA T3]

Hello!

You can buy new ones but in Europe...

Honestly I would rebuild it, it's pretty easy you will be done faster....
_________________
Silicone Steering Boots and 930 Cv boots for sale in the classifieds.
Syncro transmission upgrade parts in the Classifieds.
Subaru EJ22+UN1 5 speed transmission
http://www.thesamba.com/vw/forum/viewtopic.php?t=416343
Syncro http://www.thesamba.com/vw/forum/viewtopic.php?t=4...num+gadget

[clift_d]

New LDA units are available from Dieselkontor in Germany. They own the machine that manufactures these units and so other sellers will almost certainly get their stock from them. You can also get a kit from them to rebuild your existing LDA unit, but it's 2/3 the price of a new unit and so probably not the best option.
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1988 LHD T25 1.6TD Westfalia Club Joker syncro

[T3messie]

The repair kit from Dieselkontor includes 5 membranes to repair 5 LDAs.
So I think it is a very good option.

Greetings and thank you for the link.

[clift_d]

For the average owner, with one engine and only one LDA to repair/replace, 5 membranes is perhaps more than any one person might require.
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1988 LHD T25 1.6TD Westfalia Club Joker syncro

[Gnarlodious]

I could use a new membrane, hit me up.
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Vanagon ’83 diesel AAZ w/Giles injection, 5spd 4.57R&P+TBD and a '78 diesel Rabbit

[ZsZ]

[AndyBees]

Subscribed.

I have two complete JX engines...... with future plans!
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'84 Vanagon Tin-top, ALH TDI. 1989 Tin-top
1983 Air-cool, 225k miles, 180k miles mine. Seven trips to Alaska from 1986 thru 2003.

[jerrydog411]

[ZsZ]

[Gnarlodious]

What do you think, the B version fuels more at lower RPM? Do you think I could get more power out of my Giles pump?
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Vanagon ’83 diesel AAZ w/Giles injection, 5spd 4.57R&P+TBD and a '78 diesel Rabbit

[Bermoco]

Hello all and thanks for the recent replies.

I did place an order with Diesel Konter last week but I did not receive a reply from them yet. Christmas is big in Germany so they may still be closed. Kind of a strange web site and way of ordering. Seems that they have to okay it and you send a check? No provision for credit card service. Anyone order from them?

I did see the diaphragms and inquired about them as well. May go that route if they don't have the complete actuator in stock.
I know that I could probably repair it with some kind of diaphragm material but looking at the diaphragms that the sell they are molded and if I attempted to replace it with a flat diaphragm it probably won't have the same type of performance curve that the O.E.M. actuator has.

For now I plan on wiring the boost actuator wide open for testing to see how it impacts power. I expect it to smoke. My intention is to eventually replace this motor with a ALH TDI and am procuring parts and reading a lot of posts about doing this conversion.

I hope to get the 1.6 TD running well enough for now as I would like to take a few camping trips in it and enjoy it for a while before taking it out of service for the engine swap. It is my understanding that the TD is not too bad and much better than the NA 1.6.

Thanks again and if I end up buying five diaphragms I would be willing to sell some of the others at cost. I would prefer just buying one whole actuator though and be done with it.

[ZsZ]