Author Topic: Smoking at part thorttle  (Read 7654 times)

Reply #15June 02, 2010, 06:03:29 pm

Soot Sandwich

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Re: Smoking at part thorttle
« Reply #15 on: June 02, 2010, 06:03:29 pm »
Okay folks, finally measured my valves.  The results are puzzling, the spec for NA is warm 0.008"-0.012" for the intake and 0.016"-0.020" for the exhaust.  I measured these when the engine was definitely warm. Could the engine be too warm?  The results are as follows:

From Timing Belt:
E: 0.013"
I: 0.011"
E: 0.016"
I: 0.011"
I: 0.009"
E: 0.014"
I:0.010"
E:0.012"

All of the exhaust clearances except one are out of spec.  My first questions is should I fix them?
My second question is could this be the reason I have little to no power and a bunch of smoke?

Also, I messed around with my residual fuel screw tonight.  I found that turning the screw back would drop the revs at idle (expected I know) but, my battery light would faintly flicker and get brighter the more I turned the screw CCW.  Could this be a cheap trick to hide a fault battery?  Should I tighten the Alternator belt?  My idle is about 1100-1200rpms when the battery light turns off completely. 

Now, where the screw is now, when I hit the gas breifly I get a huge puff of dark dark grey smoke (I wouldn't call it black).  When I turn the screw back I still get a little less smoke but, it turns lighter.  I haven't put my oil cover in for the valve train yet so I won't play around too much but, I am very puzzled.   

Does anyone have any ideas about any of this?

Could the fuel screw be turned too high up for my car and it could be hurting performance with too much fuel?

Could the out of spec clearances in the exhaust valves be ruining everything?

Could I just be burning oil from the pcv and smoking so much that it's misleading me with the fuel screw and hurting performance?

Can I turn down the fuel screw and turn up the idle stop screw to compensate for my alternator needing 1100-1200rpms?

Thanks for everyone's patience!

Reply #16June 03, 2010, 12:48:36 pm

Rabbit on Roids

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Re: Smoking at part thorttle
« Reply #16 on: June 03, 2010, 12:48:36 pm »
does the oil cap dance on the valve cover if you loosen it?

and your alt or something in the system is shot if it needs 1200 revs to work right.

Reply #17June 03, 2010, 01:17:54 pm

jseeley

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Re: Smoking at part thorttle
« Reply #17 on: June 03, 2010, 01:17:54 pm »
Can I turn down the fuel screw and turn up the idle stop screw to compensate for my alternator needing 1100-1200rpms?

You DO need to adjust the idle stop screw (and throttle stop) when you adjust the fuel screw to maintain the same(previous) idle speed; 1100-1200 does seems a bit high for "idle" but I can't comment too much as I have no tach on my setup... If you are smoking and everything else is assumed correct, then I would guess you are over-fueling. Try turning down the fuel screw till you don't get much smoke, adjust the idle stop accordingly and go for a spin.... you will most likely notice LESS power though. Have you had a chance to do a compression test?

Do you just have to rev over 1200 rpm once to get your alternator to kick on (excite) or do you have to be constantly over 1200 for the light to go out on the dash?

Will be interested to what other have to say on the valves... I've never checked my clearances... probably should...
85 Golf Diesel 1.6 NA 240K miles? (odometer broken)
87 Cabriolet 1.8 Gasser 104K miles
05 Golf 2.0 Gasser 66k miles
03 Jetta Wagon TDI 112k Miles

Reply #18June 03, 2010, 01:57:04 pm

Soot Sandwich

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Re: Smoking at part thorttle
« Reply #18 on: June 03, 2010, 01:57:04 pm »
Ugh, so now at the very least I need a new alt?

I have to constantly be at 1200 but, strange thing is when I have the AC on I go down to 950rpms and the Batt light never goes on.  Could it be a weird grounding issue? They say electrical problems that make no sense are probably grounding issues.  Ah, I think I may have found some ideas: http://www.vwdiesel.net/forum/index.php?topic=21550.0

I will adjust the fuel screw and stop screw and see what happens.

Reply #19June 03, 2010, 08:14:59 pm

Baron VonZeppelin

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Re: Smoking at part thorttle
« Reply #19 on: June 03, 2010, 08:14:59 pm »
*My first question is should I fix them?

-I'd check them again when cold and see if it changes numbers much. Whoever adjusted them last time must have not had a selection of shims, or good enough selection. And just went as close as they had on hand.
I would rather be on the loose side - than the tight side - given a choice.

*My second question is could this be the reason I have little to no power and a bunch of smoke?

-Really really doubt it.
But a compression test will help you in many ways.
If nothing else but to have a baseline mark for future.

*My idle is about 1100-1200rpms when the battery light turns off completely.

-An 85 NA would not have come with a factory tach.
Maybe this was originally a TD car, or someone swapped the tach into it. But anyway - they are not always totally accurate in every case. It may be over-reading.

Take car to AutoZone when you can and have the alternator checked by their in-car machine. Another benefit of this is that their machine can detect the idle speed on our diesels, but goes bonkers much above idle. But that will let you know how well your tach is reading at idle.



Since you have a Giles pump, and the other new maintenance items, my best guess is either some of your initial timing parameters are off the mark - or the injection timing is off specs.

If you know you are good on those points, I would highly recommend pulling the injectors out and having a look at them.
The #1 compliment to a fresh pump is fresh or rebuilt injectors.
At minimum the injectors should be verified as proper when a new/fresh pump is being installed.

Hang in there, it'll come around more than likely once you get all the bases covered.

Reply #20June 04, 2010, 05:55:01 am

Soot Sandwich

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Re: Smoking at part thorttle
« Reply #20 on: June 04, 2010, 05:55:01 am »
Okay, so I'll remeasure cold and see where that gets me.

I will have to get the compression tester kit it looks like...

I swapped the diesel tach.

Can I test the injectors by cracking them at idle and seeing if the idle changes?  This way if I need new ones I can just have them on hand to replace when I do the compression check.

I believe my pump timing was 96 when I did the install.

I will try to adjust fueling and check the Alt charging with an multimeter just to be sure if its a ground or not.  I will take it to Autozone when i get the chance.


Reply #21June 04, 2010, 11:58:16 am

Baron VonZeppelin

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Re: Smoking at part thorttle
« Reply #21 on: June 04, 2010, 11:58:16 am »

Can I test the injectors by cracking them at idle and seeing if the idle changes?  This way if I need new ones I can just have them on hand to replace when I do the compression check.



Cracking them open will only tell you something if one is about dead. Like pulling a spark plug wire from a gasser.

I'm thinking more along the lines of dirty/sooted/carboned nozzles.
You'll have to remove injectors to check for that - but since you're planning a compression test - its all in the same operation.

Bosch nozzles are about $10 each through places like AhausAZ and eGerman. Most places are higher than that, or don't offer Bosch at all. You 'could' go ahead and get a set to have on hand. New nozzles are better than old ones anyday. Spec is between 50-60k miles on replacing them and having pop pressure verified.

Or you could just get new/reman'd injectors and put them in, if you don't have a local shop to check your old ones. I would definitely want new injectors or serviced injectors to go with a new inj pump. 

Reply #22June 04, 2010, 01:07:20 pm

Soot Sandwich

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Re: Smoking at part thorttle
« Reply #22 on: June 04, 2010, 01:07:20 pm »
Okay, where can i get good reman set of NA injectors for a decent price?

Reply #23June 04, 2010, 08:55:47 pm

Baron VonZeppelin

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Re: Smoking at part thorttle
« Reply #23 on: June 04, 2010, 08:55:47 pm »
Seems like AutohausAZ.com has best deal going on Bosch Reman'd.
$36 each - plus $11 core each - free shipping

The bargain priced Harbor Freight diesel compression tester seems to work great for the money. I have one, and many others here have them too.

Reply #24June 08, 2010, 07:15:42 am

Soot Sandwich

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Re: Smoking at part thorttle
« Reply #24 on: June 08, 2010, 07:15:42 am »
Okay, put the baffle in for the valvetrain. I ran the car at idle and took the oil cap off, it vibrated from side to side on while resting on the valve cover (which I expected).  No smoke, very minimal steam at first then nothing.  I had my wife hit the throttle while i stood at the tail pipe.  Black Black smoke, smells just like pure and simple diesel.  Next step, compression check with reman injector install.


Reply #25June 08, 2010, 05:03:30 pm

jseeley

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Re: Smoking at part thorttle
« Reply #25 on: June 08, 2010, 05:03:30 pm »
Okay, where can i get good reman set of NA injectors for a decent price?

I'm running "new" NA injectors from prothe/dieselvw.com; They're $24 each. I know his products are questionable and you get what you pay for, but no complaints so far, they are better than my old ones with 200k+ miles. Not sure if anyone has taken a longer more technical look at them...

I will probably have my original set rebuilt by Giles at some point though.  ;)
85 Golf Diesel 1.6 NA 240K miles? (odometer broken)
87 Cabriolet 1.8 Gasser 104K miles
05 Golf 2.0 Gasser 66k miles
03 Jetta Wagon TDI 112k Miles

Reply #26June 09, 2010, 07:44:02 am

Soot Sandwich

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Re: Smoking at part thorttle
« Reply #26 on: June 09, 2010, 07:44:02 am »
Hey! How many miles have you been running them?  I swore to myself  after one questionable experience with prothe that I would never buy anything from him that was critical to the cars operation. 

Reply #27June 09, 2010, 08:59:44 am

jseeley

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Re: Smoking at part thorttle
« Reply #27 on: June 09, 2010, 08:59:44 am »
Hey! How many miles have you been running them?  I swore to myself  after one questionable experience with prothe that I would never buy anything from him that was critical to the cars operation. 

only about 1500 miles; anyone with more miles or experience with them please chime in though... I'll post up if anything goes wrong with them.   ;)
85 Golf Diesel 1.6 NA 240K miles? (odometer broken)
87 Cabriolet 1.8 Gasser 104K miles
05 Golf 2.0 Gasser 66k miles
03 Jetta Wagon TDI 112k Miles

Reply #28June 26, 2010, 08:46:34 am

Soot Sandwich

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Re: Smoking at part thorttle
« Reply #28 on: June 26, 2010, 08:46:34 am »
Okay, swapped injectors and tuned the Giles Pump so that it barely smokes at all.  No more smoke at part throttle and the RPMs are proper. 

It appears as fast as before only it doesn't smoke.  I guess this is what 50hp feels like in 2300lbs.  I am coming from 250hp in 3000lbs. 

I didn't check compression, somehow I forgot.  I was kicking myself.

Does anyone have any idea why sometimes my tach jumps around past 3krpms?  Also, I seem to get quite a lot of vibration through the accelerator pedal.  Motor mounts?

Reply #29June 26, 2010, 07:36:29 pm

vanbcguy

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Re: Smoking at part thorttle
« Reply #29 on: June 26, 2010, 07:36:29 pm »
The tach jumping around is probably due to a bad connection on your 'W' terminal on the alternator... Check there first!
Bryn

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2004 Jetta Wagon - 1.8T - Blitzen