AAZ - Lacking torque - KKK K14 Turbo & recon pump &

[mahatmacoat]

It's a 1.9TD AAZ conversion in a panel van that has been running fine for 2-3 years. The fuel pump finally died the other day (confirmed by a professional company that rebuilt it).

I have just had the fuel pump & injectors rebuilt by a professional company & have refitted it to the van. The original pump had a faulty boost compensation valve (big dent in the can) which obviously never opened.

I have refitted the injectors & pump (to the marks I made on the backplate) & timed the pump/cam/crank with the correct tools - it took me several attempts to get it spot on! It fires, but runs smokey & with no torque (it can barely move itself). The boost compensation valve never moves whatever the revs.

I've checked the following connections:
a) from the injector pump boost compensation valve to the inlet manifold b) from the turbo to the inlet manifold
c) from the compressor housing to the waste gate actuator
& all are good.

So decided to take the turbo off to check the waste gate was closing correctly. I've removed the actuator & the seat looks poor on one side (carbon build up & it's lost some of it's chamfer).

I've had a look at the wiki & it was very helpful, but I happen to have a KKK K14!

The questions:

1. If I do a pressure check on the actuator, should it hold pressure or is it a momentary thing? I'm assuming it opens at around 10psi

2. How do I lap the waste gate on a KKK K14?

3. Could the timing of the pump be responsible for the lack of torque?

I tried using the advance for cold starting to see if this improved the torque, but didn't seem to. So I now want to get the boost compensation valve to work 1st before I look any further at timing or other issues.

I'm so close I can smell it - looking forward to smooth efficient running!!!

[Westy.Club.Joker]

You don`t see the boost over-fueling device (LDA) working when the van is stationary, you need the engine to be under load for it to work.

When you say "the can was dented", which "can" would that be? The AAZ pump LDA looks like an alloy tower, upright on the pump, the JX LDA is a small tin-can affair lay on its side with an actuation rod connected to a lever, all fitted horizontally on top of the pump.

[mahatmacoat]

The 'can' mentioned is the hoziontal diapragm cannister for the LDA on (as I now know) a JX type pump.

[Simon Baxter]

The cam plate for a JX isn't sufficient to operate the dual stage injectors of the AAZ, basically there isn't enough lift on a 1.6 camplate for the 1.9.
Did you tell them that it was the wrong pump for then engine and ask them to rebuild it as a 1.9 pump?
if you didn't then it will never be right, it really wants a 1.9 pump on it or at very least a 1.9 camplate and the pump setting to to the engine.

[HarryMann]

Thers a 1.9 Golf Diesel (AAZ) pump on eBay at the moment...

1. If I do a pressure check on the actuator, should it hold pressure or is it a momentary thing? I'm assuming it opens at around 10psi

2. How do I lap the waste gate on a KKK K14?

3. Could the timing of the pump be responsible for the lack of torque?

2) Very difficult... I've actually forgotten how I did it I hate the blinking tings, but others think the Garret T2 is crap, so there you have it.

Ah! I undid the 3 socket caps holding it on (easier said than done), noted the metal gasket position(I think), somehow jammed the valve open a bit (maybe..) and proceeded to lap the valve and seat as best i could keeping it upright and handling the whole thing as a unit...
Was it worth it? Prob. not! Didn't do the sealing faces any harm though, but if you look at any turbo wastegate valve/seat, its a wonder you get any boost at all, so they are not too fussy, this is not a cylinder pressure of 150 psi its trying to seal.

[mahatmacoat]

Damn, this is getting expensive (£180 to rebuild the pump at mates rates) plus the cost of rebuilding it or a replacement AAZ pump!!!

So how did it run okay before (plenty of poke as I ran it next to from Volkshacks 1.9TD Intercooled Doka & it held it own (only losing out at the top end which I put down to a richer tune & less weight).

I have a golf AAZ pump which I rescued off a scrap engine, but two problems a) the LDA (top of the pump) is much higher & will come through the engine cover!? and b) the pump wheel is about 4-5mm further out from the block meaning the cam belt runs just on the wheels edge (I assume I'll have to remove the backplate from the scrap engine and fit that as well to correct it!!

I'm supposed to be moving house on Monday as well - Interesting without a van!!

[HarryMann]

So how did it run okay before (plenty of poke as I ran it next to from Volkshacks 1.9TD Intercooled Doka & it held it own (only losing out at the top end which I put down to a richer tune & less weight).

Ah well, maybe your mate previously changed the cam-plate or adapted it to your AAZ in some way?

So after such an investment then, perhaps you should try re-timing it as accurately as you can, rather than setting it to a previous mark. It isn't too difficult to at least check it if you have a dial gauge.

You might also consider whether there might be air getting in or fuel getting out - somethings obviously wrong because it should be running better than you say... what does your re-builder mate say?

[HarryMann]

PS. Are you sure the throttle lever is opening fully and he has indexed back corerctly for your cable layout? This has caused me much the same problem before now, which AndySimpson diagnosed... to me it seemed just like no LDA boost fuel, but Andy found that the throttle arm had slipped.
Ask your rebuilder* if its is possible it's not exactly where it was before, because I believe it requires very accurate scribing up before disassembly to get it dead right again.

*Is he a full-time inj. pump technician or does this on the side?

[mahatmacoat]

The saga continues...

I've spoken to the guy who rebuilt the pump (a full time pump engineer doing a through the back door cash in hand job - hence no mention of the company name) and yes it is set up to supply a JX 1.6. I didn't tell him it was a 1.9 & he just set it up to the part number on the pump!!

So the results are it'll only provide enough fuel for the 1st stage of the injectors i.e. no torque.

He's going to take the cam plate & some other bits from my 1.9 pump & fit them into the 1.6 pump to keep the packaging issues sorted (so I can still close the engine lid) & then do the DTI fine tuning for me as well once i've refitted it (what a star!). This should in his opinion be as good as the 1.9 pump! Anyone know otherwise?

Have checked the throttle arm & movement & position & all good, but not one I would have suspected, so well worth a check.

The good news is I now know that my turbo is all tickety boo as I've stripped, cleaned, lapped the waste gate seat (used an old big drill bit in a pillar drill) & pressure tested it for leaks.

I've also checked all fuel lines & will do a carb cleaner test on the inlet joints once it's rebuilt & running.

I'd still like to know how people fit the AAZ pumps into the engine bay?

Thank you everyone for your help & advice, I've learn't loads about rotary pumps & diesels in general in the last week. Hopefully I can help others out in the future.

[HarryMann]

Good!

I'd still like to know how people fit the AAZ pumps into the engine bay?

1) Pickups have extra deck height so its not a problem

2) On non Doka, Sikas, you cut out the small hole and put a box over it.
Simon Baxter does a small coverplate if you look on the Brickwerks

To help: You could describe how you dismantled the valve from the diaphragm unit to grind it in, and how it is is fitted to it and I'll put it in the Wiki alongside the Garret T2 procedure?

I usually grind valves by hand, cylinders-head ones, the old fashioned way, to maintain concentricity, but I'm sure you can't pocket or upset a waste-gate one using a drill...

[Simon Baxter]

http://www.brickwerks.co.uk/index.php?p ... t&Itemid=6



Much better plan to use the AAZ pump, lot's more scope for "dicking about"

The AAZ camplate in the 1.6TD pump is a good idea though.

[mahatmacoat]

Harry - This may be a bit long winded & unfortunately I didn't take any photos, but for all it's worth....

It could do with a value for the release pressure when testing the actuator though!!


KKK K14 - Waste gate lapping

Tools:
A big clean bench, preferably with a vice (unless you like wrestling turbos).
12mm Ring spanner for the banjo bolts of waste gate actuator pipe
An old 5mm allen key with 10mm cut off the short end
Possibly a slide hammer
Possibly gas torch or good heat source
Probably a sharp 5mm drill
Probably a centre punch
Probably an M6 tap

Parts:
4 off - 6mm copper washers for banjo connectors on waste gate actuator pipe (compressor housing to waste gate actuator)
Gun gum exhaust paste - not sure this is necessary, but belt & braces!
3 off - M6 x15 cap head bolts (I imagine you'll have at least one snap/round out)
New M8 nuts for exhaust flange - Mine were steel & rusted to bits, so now stainless steel.

Once you've removed your turbo, carefully plug the oil inlet & outlet holes, the compressor (aluminium side) inlet & outlet & the turbine (cast iron side) inlet & outlet. Degrease & wire brush all the loose rust off of it & inspect the cast iron side for cracks. It would be easier to remove the compressor housing 1st, but you'll need a new o-ring if you do this (full turbo rebuild kits are available - even on Fleabay) and the rebuild guide here http://www.suzukituning.com/General/KKK ... ebuild.htm will help.

The hardest part is actually removing the waste gate actuator (the finned tube on the side with a steel pipe running from the aluminium compressor housing). I soaked the 3 cap head M6 screws in Plusgas (releasing fluid - WD40 will do nothing, so don't bother) for a couple of days & then heated them up with a gas torch & still only freed one of the three. To get good access & be able to shift the bolts you'll need to grind/cut an old 5mm allen key so it fits in under the swaged top. A ball ended allen key will just screw the head of the screw up, so I wouldn't try to short cut it.

If they round out, then a sharp cold chisel will cut the bolt head off easily. Use a stud extractor & heat to pull them out or cut them off flush to the turbine housing, centre punch carefully, drill them out (5mm) & re-tap (M6).

My waste gate came out relatively easily, but they can stick (see thread & links below). They have two tin covers between the waste gate actuator & the turbine housing, these wriggled free fairly easily for me. There is also a washer on the mating face, be careful not to lose it. DON'T WIPE THE VALVE OR SEAT JUST YET - This will tell you how things are working!

Once this is free, have a look in at the state of the seat & the valve. On mine the valve was A1 & the seat pretty poor (two cracks in the housing & a visible chamfer on about ¾ of the seat. Generally, heavy carbon deposits on the seat itself is a sign it's not closing properly.

I used a pillar drill with a 30mm drill bit on a slow speed to clean up the seat (Plugging the housing with rag to keep the swarf out), but you could make up anything to do the job (end of a broom handle & some grinding paste?!). You are just looking to re-instate the chamfer in the housing, ideally to match the chamfer on the valve, so have a look around your garage/shed for something & then gently twizzle until it's shiny & even!

Give everything a good clean & blow out any swarf. You can check the diaphragm in the actuator works by connecting a foot pump with an airbed adapter & see if it 'actuates' mine moved at around 20-30psi (Anyone know what pressure this is supposed to move at?). The actuators aren't really rebuildable - see 2nd post below. The fitting in the side of the actuator (13mm) is threaded & mine leaked. I used a wipe of Gungum to help seal this (PTFE would most likely burn out as turbos can get V.hot)

Clean the mating faces, the washer & it's recess - I used a very thin wipe of Gungum on this, then bolt it back up (make sure you've got the inlet from the compressor in the right place!!

Bingo, all should be good.


I also found these two posts from 'andy2' on the following thread http://www.vwdiesel.net/phpBB/viewtopic.php?t=1841


"I've had a couple of k14,k24 wastegates out from the housing and they are a bit of trouble to get off. There is two thin heatshield/gasket cups that are just usually stuck in the housing with rust. Basically you can only get them out by pulling on the wastegate which causes one of the shields to bend a little and then they will eventually pull out from the housing. The small bend in the one shield is nothing to worry about and they will be re-useable with out any issues. The slide hammer is definitely the tool of choice here Just keep doing what you were doing and it will come out without hurting anything "

"I've also had the wastegate's cover off too. Using two screwdrivers I just worked my way around the cover's crimp as if it were a tin can (just be careful as you will be reusing it).I had no problems putting it back together and it was in alot worse condition than the one you have. The reason I took mine a part in the first place was that it was seized open and was otherwise useless so I had nothing to loose by taking it apart. If you test it using regulated air and it works without sticking then just leave it alone. Dr diesel and I have played around with the screw on the cover to raise the opening pressure but it doesn't make much difference and if you screw it in far enough you can reduce the valve's opening travel as the screw also acts as a stop when the valve is fully open. This will raise boost by simply not allowing the wastegate to open all the way and will send EGT's way up. I would leave that adjustment alone Or put a bigger spring in the wastegate. So for anyone else looking to raise boost on the k14,k24 the best way is to just put a bleed in the line or use a boost controller, just leave the screw alone!

BTW just for reference the k14,k24 wastegates are not interchangeable, as I found out also "
[/b]

[HarryMann]

Many thanks for that, now in the Wiki.