Author Topic: Is it possible for lda starwheel/pin adjustment to cause these major problems?  (Read 11905 times)

Reply #15December 25, 2011, 06:28:32 pm

damac

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Ok so I blew the lines and cleaned the pickup again.

Hooked back lines to car and for the hell of it used the car to prime the system.  I was very surprised that within 10 seconds the car started with no glowplugs!  And within another 10 seconds it was priming pre filter with all fuel fast!

Then the car stumbled to try and get rid of the air/fuel pockets coming from the fuel filter on the car.

That cleared and I went to drive it.  Car did the same crap and it turned off a few times within a mile.  I coasted back home and it wouldn't hot restart.  So I yanked the inlet immediately and return and put it in a jug and within 10 seconds the car started back up and when the inlet was solid I could stop/restart right away.

So cracking all the stock lines somehow releases something but it doesn't take much real world driving for it to go downhill fast and restrict inlet fuel I assume?

So now I'm starting to wonder if it could be my fuel filter to some degree and/or some restriction downline.

I am going to go get another inline fuel filter and try and get the car to act normal on the driveway again from a big jug and let it run for a while and hopefully get most air out and see if it reacts to idle and throttle ok.

Then I will hook that back to the car lines and see what happens and go from there.


As far as blowing the lines out, I never did it with the cap on?  I thought it would blow something up?  I have been running it at various times with the cap off and that didn't help during the times the car was spazzing out.
1985 turbo diesel jetta

Reply #16December 25, 2011, 09:00:18 pm

burn_your_money

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You should get a vacuum and a pressure gauge. Hook the pressure gauge up to the return line and the vacuum gauge up to the feed line, both right at the pump. That should give you an idea as to what is going on.

Actually, hook both feed and return up into a jug with no filter (make sure it is clean) and go for a drive and see if it acts up.
Tyler

Reply #17December 25, 2011, 10:19:41 pm

8v-of-fury

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Damac, I'm sorry to be the one to say this.. but your going off half-cocked here buddy.

Your trying 13 different things at once to solve your problem.

The no hot start after it has died is not a hot start issue. Its an issue with there being no fuel in the pump, why do you think it stopped running in the first place? What you need to do is slow down here, and step back.

You have a restriction, or had, you didn't really say if you could get air to blow through all the lines.. This needs to be dealt with first and foremost if you haven't already. After that, the pump is clearly having an issue sucking fuel from the fuel tank of the car. This is why you can start off your gravity feed at any time and run it until your feed runs out.. and as soon as you hook it back up to the cars fuel lines it runs for a few minutes on what is left in the pump. trust me they can make it a few minutes at idle on less than 500ml.. just about what the pump holds.

SO here is what is most likely your issue.

1: You still have a tank restriction somewhere causing it to not pull fuel from the tank. if the return is plugged it will not pull fuel because it can not send the used warm fuel back to the tank.. if the feed is plugged it will try to pull fuel, but will more than likely start to pull air in through every connection it can.. pumping air is easier than fuel.

2: the main-shaft seal of the pump has deteriorated and is sucking air directly through the pump when it tries to suck fuel from the tank.. This is not seen when being gravity fed, or on a very short feed line. Pulling fuel 10feet from the tank isnt as easy as you'd think.

Do as Tyler (Burn_Your_money) suggested and setup a small 1qt jug of clean diesel fuel with no filter and run both feed and return line in to it from the pump. You should get a few miles drive out of a liter jug easy. If you have no issues on this test drive you have found your issue. It is either one of the two I stated earlier.

Seriously though, you just gotta calm down. Tackle one thing at a time.. because changing 13 different settings all at once.. you'll never know which one of them made the change happen.

Baby steps. Gotta Run before you can crawl ;)

Reply #18December 26, 2011, 12:55:33 am

guy plain

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 an easy one to try is run it with a loose fuel cap....my (vent) plugged..and i could,nt keep my 91-1.6 td running...thats all i did to get it going again......easyest and fastest thing to try....

Reply #19December 26, 2011, 05:59:27 pm

damac

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Sorry I edited posts and might have taken other info out along the way.

I just  Ran a 5 gallon jug of diesel into the passenger seat and ran the return and input line, new seperate lines than were on the car.

Same deal when I go out there cold and initially try and prime the lines.  It pulls fuel rather quick, and within 10 seconds of hitting the starter the car is starting without glowplugs!  So its burping to life to purge the initial air and rather quickly a a solid stream of fuel comes from the bucket, just has other sources initially.  Then its taking about 5 minutes for the constant foam from the return line to subside. 

So it was idling ok and I took it for a drive and it wasn't very long to see the same issues.  Car was hard to get out of its own way, boost is barely trying to build.  Smoky, lack of power and just drove around the corner before it shut off when letting off the throttle.  Did not see the previous pressure out of either the inlet or outlet, no air in the lines. 

Took like 20 seconds of cranking and I got it started with  pedal down, screamed it around the corner again, died and I coasted back to the driveway.  The car sounds like its firing on all 4 during this.

Now one thing I noticed again is as the car gets up to temp on the driveway and I push the advance lever back in that the car might hang on a good idle but it seems to want to idle at 800 on the tach.  If I rev with my foot to just under 1000 the engine smooths out and it doesn't sound like its about to die.

After all these bubbles are purged my return line puts out a steady solid flow which increases with revs.  The lines seem perfectly primed so I let it idle for a while in the car and held the return line up and watched it.  If my diesel can was restrictive I assume within 5 minutes it would have started sucking bubbles and/or start to run rough and see more bubbles in the return but that isn't happening so I assume its pumping.

How would a normal 1.6 td react with idle set to 800?  I know its lower than spec but from what I recall it should atleast stay running and vibrate.  I checked again my locknuts and governor arm screws and they were all as they have been.  Throttle cable is good, everything turns  and returns smooth.

But it does appear when messing with throttle lever at idle that there is a little dead zone. 

I couldn't take that anymore and decided to just warm it up and bump the idle a few turns in to get a hot just under 1000 rpm idle.  Now it seemed to be returning exactly to that spot when I would stab the pedal and let off.  But its night time now and I am too scared to mess with it.

By turbo and boost hoses are all hooked up as well and its obviously not liking these settings.   And my max rpm is still <5000


So I am going to put the lda settings back again to my previous pictures taken for reference before I even cracked it open.

Then I am going to go out tomorrow am like nothing has happened and try and drive the car and hope it magically fixes itself.


Now lets say I keep having these same problems, is it possible that its all flowing and staying primed, but just not well enough for the pump to put out correctly?  Should I then try and inline diesel pump pusher back near the tank?  Hate to waste the money but they have a low psi diesel pump off the shelf at kragen for $60+tax and I need to get back on the road.

Thanks again.
1985 turbo diesel jetta

Reply #20December 26, 2011, 06:09:56 pm

burn_your_money

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It pulls fuel rather quick, and within 10 seconds of hitting the starter the car is starting without glowplugs!

And my max rpm is still <5000

If all you did was remove the feed and return line, the pump should have stayed mostly primed and fired right up with glowplugs. Or were you trying to do some other tests by skipping the glowplugs?

Do you have a governer mod? If not, less than 5000 is completely normal for a stock pump.

When you were running off the 5 gallon jug, were you using the filter?

Did you somehow mix up your in and out bolt on the pump? Have you played with the timing? How long was this car running properly before you played with the LDA and everything went nuts?
Tyler

Reply #21December 26, 2011, 07:19:24 pm

damac

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Car has been running 700+ miles/week for atleast a few months since I last timed the car.  Only decided to mess with lda stuff during winter break due to days off, not because of car problems.  I didn't touch any of that other stuff.  Just to confirm the inlet is regular bolt, outlet is OUT and I pricked it with a piece of wire just in case.

The pump was resealed, new mainshaft bushings and stuff.  Has been working great, not losing prime, etc.  No governor or other mods, stock fueling.

On the glowplug front, I don't need them hot, but I was hinting to my first cold starts of the day or when I leave the car for a few hours in the cold.  If you were using the stock dash light as an indicator is what I'm going by, but the starter chugged it to life!

Note I just found out during this that my battery was draining down quick, like within a day.  I was having harder starts in the am but could tell the power would dropoff after just a couple starting cycles.  So I got that replaced after all these problems arose and I got a tdi starter from somebody on here.  Spins that sucker faster so you can't count the revolutions like before and is constant  for quite a few cycles :)  Love that thing, so I guess it just built up enough heat from turning over so fast.

Right now I have the jug rigged with new lines seperate from the cars runs with NO filter.  Scared me but I don't know what to do and wanted to start from square one. 


Right now I feel from the bucket there is no wierd pressure on either side.  When I shut it off there was no shift.  No bubbles, etc.  Inlet and outlet are so solid full of fuel that I had to watch the return line put out fluid into the can while letting it idle to confirm it was flowing at all.  Reving at this point also did not produce any signs of bubbles.  It wasn't dying at idle but you could tell it was trying to hover at 800 so thats why I bumped it while hot to just under 1000 and had to come inside.

I will hook up the vacuum on the inlet side tomorrow as well just to get confirmation of whats going on.
1985 turbo diesel jetta

Reply #22December 26, 2011, 08:09:19 pm

745 turbogreasel

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Try hooking up the  factory return line, if that is cool, put it back to the bucket, and try the factory feed through the stock filter, then (if all is still well)from the tank.  You might narrow it down some.

What is your exhaust like?  if a hairball(baffle or packing) blocks your muffler, you can get smoke with a stall as time goes by.

FWIW, I get 5600 in 2nd going uphill on my unopened pump.

Reply #23December 27, 2011, 06:32:01 pm

damac

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I messed with it more today and the only difference between the bucket with no filter and other lines is after it was primed I haven't seen a hint of bubbles or pressure on either side.  Not even this morning.

The idle I raised last night was now reflected early on.  I started having more problems the longer I ran it and idle started to drop again so I gave up on that one :(  Governor springs/arm are indexed and free.

Todays cold start took me a second try with lever out and some gas.  Didn't even act like it wanted to start but did the 2nd time with a cough.  That is a hard start for me.  Car is not spinning over slower with lever out.

So usually mine catches, coughs for less than 10 seconds then runs smooth with cold start lever out.  There isn't white smoke within a minute.  Then I usually take off after 5 and can push the cold start lever in and go.  No stumbling but there still might be a hint of white puffs until up to temp.  Then nothing when idling.

My initial test seemed ok on the timing front but the longer I ran it the worse it got and I could see even with the lever out, there was now just a hint of white puffs out the tailpipe.  Push lever in and steady puffs and starts stumbling.

So the car is tricking me each time.  Get it started do the warmup and almost feel like driving it off and then the problems set in just sitting on the driveway.

Its like the timing is being retarded on the fly as the car gets warmer, and the idle is being pulled down.  And in a real world driving application it takes less than 1/4 mile of pounding on it before it will just die when letting off the pedal as it tries to idle.  


Anybody happen to know of somebody with a pump for sale near sonoma county,ca?


Just for the hell of it I'm going to take my trucks nice carrier low pressure diesel pump and put that on the jettas stock lines, it will overcome any issues and feed the pump.  I am curious if it will help anything.  I'm going to check the timing belt again(tension looks good, tensioner isn't loose), then verify pump timing just for the hell of it.

« Last Edit: December 28, 2011, 01:17:59 am by damac »
1985 turbo diesel jetta

Reply #24December 28, 2011, 02:55:37 pm

damac

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damn, so i just hooked up my electric pump to the car with the gas cap off just in case.

it seemed like an improvement as far as startup and clearing itself out.  the car started on first glowplug cycle, cold start lever out, a few misses with the initial puff of smoke and within 20 seconds it was clear.  Also pushed the lever in before warmup and tailpipe was also clear.

I had it sitting idling for a long while to watch for bubbles, etc.  The idle would seem to repair itself both sound wise and on the tach but it would happen all of a sudden by itself, you could hear the car run at its best and with the slightly higher idle i set a couple days ago.

problem is in spurts in the same running session i saw the idle lope around a bit and drop to <1000 and with that would come the hint of white smoke out the tailpipe.  when its running crappy like that i pull the cold start lever and niether the idle or smoke patterns are helped.

i just shut things off and did not see a hint of bubbles or fuel shift in either way.

i am not seeing a hint of fuel leak in the engine bay or hissing when the car is turned off.  when the car is running it sounds like its firing on all 4 and evenly.

my last ditch effort here is to run just the electrical pump into the jug with new in/out lines that i can see and after that i suppose i must give up :(


Now again I do see fuel under the lda pin when I pull it up, but no hint above or at the vent.  So could I run the car with that lda top off and pin out to take a look at that pin and for fresh fuel or will the pin shoot out too far and then I can't get it back in?  If its leaking still could that internal leak cause my loping idle issues?


------------------------------------------------
another edit. 

hooked up directly to the bucket again with different lines and my electric pump.  no bubbles soon after switching lines over.  got it up to temp idling on the driveway for 5 minutes and wanted to take off and didn't take long for the car to start doing the same thing.

i couldn't see any bubbles/pressure on either side after shutdown.

fuel was flowing steady, more with increase in throttle.

started stabbing the throttle and every time it got worse and worse like the idle speed was shifted down.  then it would die around 800 rpm, it would restart a little slow with no gas.  until i screamed it and let it down and it died.

tried to hot restart for 10 seconds with no pedal and nothing.

tried again with pedal to the floor and it stumbled a tad after 10 seconds and started and wanted to idle at around 800 rpm so still sounded rough.

i ran the pump with the lid off to look at that lda pin and all i would see is after i pushed it in it would slowly move out and stop a tad, i couldn't detect a leak after i sucked up the other stuff.

so i am at a loss here.  i would have messed with timing but again resisted the urge due to these other problems stopping me from driving it.

all the external screws are still locked in place.  governor arm is indexed, i haven't had a pump act like this before :(


I think all of these tests show that it isn't a fuel flow problem?  Something internal happened to the pump when I took the lid off and messed with those settings, although I still can't find concrete info on if thats possible.

I think at this point I have to take the pump off the car and bust it open but what the heck am I looking for?  Do I just make sure its all put together ok and try and run it again?  Anything specific that can cause this fuel shift?

Is it possible something really bad is happening and there is something wrong with the engine as it gets up to temp to bog the car down or something?
« Last Edit: December 28, 2011, 07:07:04 pm by damac »
1985 turbo diesel jetta

Reply #25December 29, 2011, 08:22:27 am

mtrans

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For air leak
Put 6 bar on inlet,block OUT and put pump in water and see any air.
Do this ONLY 20 sek- it`s test by Bosch
I`ll improve my English

Reply #26December 29, 2011, 07:35:30 pm

burn_your_money

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Do you have a spare set of injectors you could swap in? Even NA ones would be fine.
Tyler

Reply #27December 30, 2011, 12:42:51 am

damac

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I don't have other injectors or a pump sadly.  I'm stuck and need to get back on the road so I'm yanking the pump tomorrow and hope something sheds some light.

Car is doing the same thing and before coming in as the cars idle was loping and get lower I pulled the line from jug and hooked it back to the car and could feel the line suck and empty out that bit of line rather quickly and it started sucking fuel pretty quick as well.  Then it hiccuped on the air pockets but I revd it and kept it going and then the inlet primed and the outlet foamed to purge the air.

Just leaving the car alone idling it maintains before I mess with the pedal, just like when I did diesel purge which is wierd.  Anyway after the foaming stopped I turned it off and didn't notice anymore bubbles either way or fuel moving in either direction.   Cracked open the fuel shutoff solenoid and it was full of fuel, starting gurgling and then fuel ran away from the pump and the level lowered.

On that front I still can't detect a drop of wetness on anything external to the injectors and heard no wheezing once turned off.  And again if I leave it alone right now hooked to the jug I can go outside in the morning and fuel is still primed with no air issues on either side.



----------------------------------------edit

i yet again checked all timing and its still the way i set it months ago.  the belt is still tracking in the middle actually.  all the ip bolts are secure and all that stuff.  crank is rock solid without a hint of any wobble.

one thing i noticed that is different since i got the car a year and a half ago is the compression.  its now easier to turn over crank bolt with a ratchet until it fights back and i push through it.  it had major white blowby when i first got it so it imagine me running the car all the time hasn't been good on it wear wise?  that wouldn't have anything to do with my issues though would it?  it starts right up when healthy when down into the teens.  hot starts almost instantly as well.

next step is popping the cover of the pump off just to see if i would happen to have something hanging up maybe?  if i can't find anything there i guess i rip the whole pump apart to clean it and reassemble and try again.  

---------------------------------edit---------------------------

darn, i pulled the pump apart looking for something out of place.  all seems well and indexed.  not really a hint of any dirt or buildup.

im going to just blindly put this back together and hook it to a drill to start.

my only question is, is it possible to have wierd fuel delivery issues by messing with way the governor arm is indexed with the stoppers?  I saw some old threads talking about setting idle off the governor and not the stoppers.  Even though my car has been running it made me wonder because the top was changed from scratch because the top piece of the lever was bolted on upside down which change the stopper positions and this was flipped and started over once the pump was resealed.
« Last Edit: January 02, 2012, 11:41:38 am by damac »
1985 turbo diesel jetta

Reply #28January 05, 2012, 12:57:14 am

damac

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Long story short, I retimed everything, pump at .041".  By ear I could swear it could use the slightest edge towards but advance but I will leave it.

I hooked up my pump that I cracked open to reassemble and clean back to the car, primed to the filter then hooked to the pump.  Was able to get fuel on its own and I let it run for a good half an hour to try and purge the air. 

I had least aggressive settings on the lda/starwheel and fuel screw turned in like 1/4 of a turn just to mix things up.  I took it on a drive around the block and it did not die, but was a dog, not building much boost, couldn't hear the turbo.

I was not getting a cloud of smoke and the idle still didn't seem perfect.  Just a tad of hunting close to ideal setting, but it didn't start shaking or try and die so that is good.


I came back and changed the starwheel back to where it was before this mess started and about 1/4 turn away from where the pin used to be set.

Took it on a drive, again power is off but better, no smoke clouds and again idle may not have been perfect.  I took it on the freeway and I got to 4-5 boost max in 4th gear trying to merge on freeway but the speed would max out and quit reving with foot to the floor?  5th gear practically useless.


I have no idea whats going on here but at face value right now it seems like the fuel screw in the past when I tried to turn it out as an experiment for better mileage.  Turned into a useless dog.   

So either there is really something crazy going on here, or if I spin that lda pin 1/4 turn more it will be back to the car I had and probably with even more smoke due to fuel screw.  Is it possible for it to change so drastically with such a small adjustment?

I will find out tomorrow and am crossing my fingers I can somehow tune this thing, but again I am baffled as to how this is going down.
1985 turbo diesel jetta

Reply #29January 05, 2012, 04:19:12 am

theman53

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I would turn everything back to where it was and start there. The way it sounds of not reving more is it is out of fuel or up against the governor. If it still acts bad turn in the fuel and see if that will get you what you want.