Fixmyvw.com

Author Topic: '85 Jetta problems:low power, smoky, very loud!  (Read 3012 times)

April 25, 2012, 12:55:43 pm

quanstrom

  • Newbie

  • Offline
  • *

  • 17
  • Personal Text
    1985 jetta NA
'85 Jetta problems:low power, smoky, very loud!
« on: April 25, 2012, 12:55:43 pm »
Hi everyone.  I've been reading your forums ever since buying my 1985 Jetta NA about a year ago.  Have done many projects myself with help from your great discussions here.  I registered yesterday so I could get help with my newest problem.  Long story; please bear with me, and thanks in advance for any suggestions you may have.

Yesterday I went out and hopped in White Fang, as she's known at my house, to run an errand.  Last drove the car about two days ago, no problems then obviously.  Last night I was not able to start the car.  Disclaimer: have been running B75 or so for several months now with very good results; that's what's in the tank now.

So after cranking too much and not stopping and thinking enough, I pretty much flattened my sub-par battery.  Threw the jumper cables on and took apart the air filter box.  Filter was a bit dirty and I left the lid and filter off to eliminate air restriction as a possible culprit.  I remember reading in one of Nigel Calder's books once that a diesel engine will run indefinitely on a stream of WD-40 sprayed into the air intake, so I shot some WD in to the open manifold as my girlfriend cranked.  Didn't seem to make much of a difference, certainly didn't start at this point. 

Next I disconnected the fuel filter outlet and used a vacuum pump to draw some fuel through.  There was fuel but it didn't seem to be flowing freely so I swapped out the filter - had a spare in the trunk.  I primed the new filter by hand and had my assistant crank the engine while I attempted to bleed air at the injector nuts.  The engine was so close to starting at this point and I think I sprayed more WD-40 into the intake.

After a few more attempts, vroom!  Uh oh, I mean VROOOOOOOM.  It only ran away for about two seconds I would say, and I was able to stop it by turning the key to off, thus closing the solenoid.  I let the engine sit for a while then tried again with something handy to stuff into the intake to block air if it happened again.  This time the engine started and ran and sounded about right.  I let it idle for five minutes before I got in to drive and charge up the battery...case closed, except...

Here's where the weird problems start.

1. Engine is incredibly loud.  It sounds good, like a diesel, but at least 50% louder than before.  And strangely, the noise doesn't seem to go away above idle like you might normally expect.

2.  Low power.  I actually stalled the engine for the first time ever getting into first because I am not accustomed to having to rev it up so much just to get into gear.  Couldn't even make it up a steep hill (this is Seattle after all) last night.  I just had to stop and turn around.

3.  Tons of smoke.  I thought at first that it might just be WD-40 burning off, but it didn't subside too much throughout my drive last night.  It was nighttime, but it looked mostly white.

Here's what I have tried: Loosening each injector nut in turn proves that all four cylinders are working.  I drained the water trap under the car and got no water.  Just fuel and some dirt/rust/whatever.  Car sounds different at idle with cold start handle pulled out, but not the same different as before...

And, lastly, this morning the car wouldn't start when I tried to drive to work.  Could the timing be advanced so much that it doesn't want to start?  Could I have jumped a tooth or more on the timing belt during the runaway?  How about injectors, one or more may be injecting fuel but not atomising well and therefore creating all this excess smoke and no power?

I think my next step is to remove injectors and either replace or try to have them tested somewhere first.  I am not too keen on injection timing but will have to learn if you guys think that's an issue: it's the only thing I can think of that might possibly affect the "loudness" of the engine like that.

Thanks for reading, and feel free to harass me for spraying the WD-40 in the intake like a fool.  Hopefully I didn't do any permanent or terribly expensive damage.  I just had a new clutch put in three weeks ago!  Yikes!



Reply #1April 25, 2012, 07:57:33 pm

theman53

  • Global Moderator
  • Veteran

  • Offline
  • ****

  • 7837
  • Personal Text
    Holmes County Ohio - North Central Ohio
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #1 on: April 25, 2012, 07:57:33 pm »
How much wd?

I could see 2 possibilities. Bent rod from hydro lock or destroyed precup/rings from detonation.

If you didn't change the timing it should have been no different than before.

Some other less expensive options: maybe you wrecked the starter and battery with all the cranking and that is why it won't go now. No clue on your power loss though

Reply #2April 25, 2012, 10:05:30 pm

quanstrom

  • Newbie

  • Offline
  • *

  • 17
  • Personal Text
    1985 jetta NA
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #2 on: April 25, 2012, 10:05:30 pm »
theman, thanks for reply.  I'm not sure whether I have good or bad news to be honest.

After work today I had a chance to look at things in daylight and I discovered lots of little rubber bits under the hood.  The good news is, the timing belt is still in one piece, the bad news is that it's about half gone! I can't believe that it didn't break. The belt feels pretty tight still.  It might have jumped a few teeth or something though, that would explain the loud noise, smoke, loss of power? Was I running off two cylinders last night, the other two have valves that are smashed in?

The engine cranks over and sounds more or less normal, but it won't fire up. I certainly can't hear anything pinging around or knocking in there while I'm cranking.

Photos to follow in a few minutes, please offer any advice you may have. Thanks for reading.

Reply #3April 25, 2012, 10:31:13 pm

quanstrom

  • Newbie

  • Offline
  • *

  • 17
  • Personal Text
    1985 jetta NA
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #3 on: April 25, 2012, 10:31:13 pm »
The belt...
« Last Edit: April 26, 2012, 12:25:59 am by quanstrom »

Reply #4April 25, 2012, 11:16:02 pm

billybobf

  • Veteran

  • Offline
  • ***

  • 318
  • Personal Text
    89 golf 1.8 digi, 1.6 na in pieces in the shop
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #4 on: April 25, 2012, 11:16:02 pm »
can you put the engine at TDC through the transmission bellhousing and pull the valve cover off?  if its even a tooth off on the belt, your going to know it just by looking I would think

Reply #5April 25, 2012, 11:58:43 pm

quanstrom

  • Newbie

  • Offline
  • *

  • 17
  • Personal Text
    1985 jetta NA
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #5 on: April 25, 2012, 11:58:43 pm »
That's a good idea.  Unfortunately, I live in a little apt. and just park on the street and it is raining hard today.  Might have to wait until this weekend then I can dig in a little and see what I can find.

Reply #6April 26, 2012, 12:05:11 am

billybobf

  • Veteran

  • Offline
  • ***

  • 318
  • Personal Text
    89 golf 1.8 digi, 1.6 na in pieces in the shop
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #6 on: April 26, 2012, 12:05:11 am »
I understand the weather as a am just a few hundred miles south on central oregons coast, and yes rain sucks.

Im not right there on top of the diesel runnings, but I do know that its simple enough to peek into the timing area and check that the mark on the back of the cam is where it should be. should tell you if a new timing belt is a good idea or if you need to go full head pull. BUT like they said, our diesels are a 23.5:1 or so compression ratio, I wouldnt go putting ANY liquids that arent super regulated (like diesel through your IP) as there is NO ROOM for them. Ive fired up a big ford diesel on gas dumped down the intake with what seemed to be no ill effect. But wouldnt DARE on a VW

Reply #7April 26, 2012, 09:59:29 am

libbydiesel

  • Global Moderator
  • Veteran

  • Offline
  • *****

  • 3416
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #7 on: April 26, 2012, 09:59:29 am »
Don't spray anything in your intake.

If you suspect an issue with the timing, do NOT use the starter motor.

If you haven't wrecked your engine from doing one of the above, you are lucky at this point.  Replace the belt and tensioner.  Most often the belt eats itself because whoever installed it, installed it too tight.  Having the timing belt too tight is incredibly costly.  It will eat the intermediate shaft bearings causing low oil pressure and it will destroy the pump shaft bushing incredibly fast.  Full pump rebuild is required for bushing replacement.  When replacing the belt and tensioner, the tension should be set so that with both hands gripping the belt, you can still slide it back and forth on the cam sprocket 1/8".  Using the proper tension tool at least once is most advisable to get a feel for just how loose it's supposed to be.  With the belt replaced, crank it over by hand several times to feel for anything internal hitting.  After several rotations of the engine, check to see if the belt is tracking in the center of the injection pump.  If not, then adjust the belt tracking by moving the injection pump mounting bracket.  Sprocket up, lines down makes the belt track farther from the engine.  Sprocket down, lines up makes the belt track closer to the engine.  Pump needs to be removed for adjustment of the bracket.  Once it is all correct, bleed the air from the pump.  I temporarily use an IN bolt on the Out location and suck the fuel through with a primer bulb.  Start it up and see how it runs.   

Reply #8April 26, 2012, 10:03:48 am

wdkingery

  • Veteran

  • Offline
  • ***

  • 494
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #8 on: April 26, 2012, 10:03:48 am »
Hahahaha I've done did all that! Sounds like you broke some piston rings, If the smoke truly is white. If it's black, you may have some fouled injectors, although it took straight motor oil to jam mine.. I don't know if b75 is enough.

Reply #9April 26, 2012, 10:16:11 am

quanstrom

  • Newbie

  • Offline
  • *

  • 17
  • Personal Text
    1985 jetta NA
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #9 on: April 26, 2012, 10:16:11 am »
Thanks for the thoughts libbydiesel.  This weekend I will have to cut away what remains of the old timing belt and try to turn it over by hand.  That will be a good way to figure out if the pistons are (still) hitting anything.  If I have crashed into some valves, which is certainly possible, it seems like my worst case scenario is probably rebuilding or just replacing the head, yes?  Unless I buggered up the piston crowns...anyone have experience here, are pistons usually okay or not?

Thanks...

Reply #10April 26, 2012, 10:33:22 am

libbydiesel

  • Global Moderator
  • Veteran

  • Offline
  • *****

  • 3416
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #10 on: April 26, 2012, 10:33:22 am »
If you "cut away the old belt" then you will need to install the new belt before rotating it by hand.  There is always at least one valve open so without a belt installed, you will have interference.

Reply #11April 26, 2012, 11:15:04 am

quanstrom

  • Newbie

  • Offline
  • *

  • 17
  • Personal Text
    1985 jetta NA
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #11 on: April 26, 2012, 11:15:04 am »
Don't worry, I will just be sure to rotate the camshaft and crankshaft at the same time; I have two hands, after all. ;)

Just kidding.  Thanks libby.

Reply #12April 26, 2012, 02:28:30 pm

bajacalal

  • Guest
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #12 on: April 26, 2012, 02:28:30 pm »
That sounds incredibly difficult to achieve a correct relationship of the crankshaft and camshaft turning them over by hand, the timing between them must be a precise 2:1 ratio. There is only around maybe 0.030" of clearance between the piston and valves when everything is working properly.

And you wouldn't be learning anything by doing so. Of course it's possible to turn them over at the right speed relationship so nothing hits, or else your engine wouldn't work at all, but that's what your timing belt is supposed to do in the first place. You need to check to see if your timing is accurate with the timing belt on and see if everything is where it's supposed to be at TDC, if it's not, fix that and probably replace the belt too.

If you bent a rod, it may not result in piston-valve interference or hitting anything but you would lose compression and it would run poorly.

Turn it over with the timing belt in place and determine if everything is where it's supposed to be at TDC and check compression if you have the means to do this. Start with the simple checks and work down from there, no need to tear everything apart just yet.

Also, you mentioned that the fuel water separator (the one under the car) is still present on your car. These were known to fail and leak diesel out and air in, the air in your system will cause poor running, low power and make it difficult to start. I think most '85 Jettas would have that thing bypassed by now, the general consensus is that they aren't necessary (there is an additional water separator on your fuel filter) and the fuel quality has largely improved since 1985. If you have a clear section in your fuel line where it goes into the pump you can look for air bubbles.

Reply #13April 30, 2012, 11:10:16 am

quanstrom

  • Newbie

  • Offline
  • *

  • 17
  • Personal Text
    1985 jetta NA
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #13 on: April 30, 2012, 11:10:16 am »
In case anyone is wondering...

Spent a beautiful Saturday putting a new timing belt into White Fang.  Didn't have proper IP/camshaft locking tools, but also didn't really need them in the end.  It was easy to see that the timing was off by a tooth or maybe a bit more once everything was opened up.  The car fired right up at the end of the day and I would argue she runs smoother than before.

http://vincewaldon.com/index.php?option=com_content&task=view&id=24&Itemid=28 was very helpful for me as a quick primer before I tore everything apart as it was my first time changing a timing belt.

Anyway, now all all have to do is fix this damn oil leak coming from the head.  Could it be the camshaft oil seal?  I guess I know what I'm doing next weekend...

Reply #14April 30, 2012, 11:19:46 am

libbydiesel

  • Global Moderator
  • Veteran

  • Offline
  • *****

  • 3416
Re: '85 Jetta problems:low power, smoky, very loud!
« Reply #14 on: April 30, 2012, 11:19:46 am »
Is the belt tracking correctly in the middle of the injection pump sprocket?

 

Fixmyvw.com