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General Information => Troubleshooting => Topic started by: burningchrome on February 17, 2009, 06:55:45 pm

Title: Blue smoke
Post by: burningchrome on February 17, 2009, 06:55:45 pm
I have an 86 Jetta TD. I'm getting a fair amount of blue smoke at start up and under acceleration. The PO gave me some valve stem seals with the car saying this would fix the problem. Should that do it or is there something else I should look out for?
As well there diesel on the outlet side of the IP. It seems to be originating somewhere along the fuel return line. When I squeeze the braided line it oozes diesel. Is this a common problem? Will some new hose fix it?
Cheers,
Etienne
Title: Re: Blue smoke
Post by: jtanguay on February 17, 2009, 09:43:23 pm
Quote from: "burningchrome"
I have an 86 Jetta TD. I'm getting a fair amount of blue smoke at start up and under acceleration. The PO gave me some valve stem seals with the car saying this would fix the problem. Should that do it or is there something else I should look out for?
As well there diesel on the outlet side of the IP. It seems to be originating somewhere along the fuel return line. When I squeeze the braided line it oozes diesel. Is this a common problem? Will some new hose fix it?
Cheers,
Etienne


yep get some new fuel return hose.  vacuum hose looks identical, but won't last long.

valve stem seals aren't such an easy job, but luckily they're cheap!  :lol:

i would believe it to be valve stems as well.  when you shut the motor off, oil will leak down the valve and sit there until you start the motor, and it gets burnt off.  high rpm will also cause the oil to leak into the cylinder causing that to happen as well.
Title: Blue smoke
Post by: Smokey Eddy on February 18, 2009, 12:42:29 am
could it be? a PO who knew what they were talking about!?
Title: Blue smoke
Post by: burningchrome on February 18, 2009, 05:14:03 pm
I flipped through my bentley and it does look like replacing the valve stem seals is a big job. It seems as if I should work the seal replacement in to another maintenance job. The timing belt was replaced a couple of years ago  if I wait another couple and do everything then is the engine at risk with leaky stem seals.
Cheers,
Etienne
Title: Blue smoke
Post by: jtanguay on February 18, 2009, 05:27:25 pm
Quote from: "burningchrome"
I flipped through my bentley and it does look like replacing the valve stem seals is a big job. It seems as if I should work the seal replacement in to another maintenance job. The timing belt was replaced a couple of years ago  if I wait another couple and do everything then is the engine at risk with leaky stem seals.
Cheers,
Etienne


perfect time to change valve lifters if you had any sticky ones...  it's a complicated job, but definitely not impossible.  just a few days ago i recall viewing a post on how to make your own valve spring compressor, which is required.  i think that is the most difficult part of the job.  best part about the interference engine, is that you can bring that piston to its maximum height so that the valve doesn't fall into the cylinder (that would be a nightmare!!!)

in the meantime, you could just run an oil stabilizer or something like wynn's stop leak/burn.  but beware those products thicken the oil quite a bit, and will severely hurt cold weather starting.  -20C starting is near impossible using those products... trust me  :lol: they do work though.  mileage may suffer a small bit as well.
Title: Blue smoke
Post by: burningchrome on February 18, 2009, 05:40:38 pm
I saw the same post about the compressor, I'll be bookmarking it. I also read about the bonus of an interference engine. But could you clarify something for me? If piston 1 is at TDC where are the rest? do I have to turn the engine as I make my way down so each piston is at TDC.
I'll check out the wynn's product. I'm on the west coast of BC so cold here is -1, heh heh.
Cheers,
Etienne
Title: Blue smoke
Post by: Quantum TD on February 18, 2009, 06:27:23 pm
Numbers 1 and 4 pistons are both up at TDC mark on flywheel. Number 1 is on compression stroke, number 4 is on exhaust stroke. Rotate 180 degrees, and #s 2 and 3 are at TDC.

ZDMAK sells the tool to compress the valves is you don't want to make one. It's designed off the OEM version. I can't speak to quality, but I have bought tools from him, and they've been pretty good. The guy however is a condescending douchebag.

You can do the seals with the head on the car. If you do so, make sure your flywheel TDC mark is correct. I've heard of, and personally seen (twice) where people had incorrectly installed the flywheel. Better yet, pull your # 1 and 2 (or, 3 & 4) injectors, slip a thin wire like a coat-hanger in the hole, and rotate till TDC. Then you're certain.

Anyway, I have a friend who used to do it to 8v gassers all the time. I think he used to slip rope in the spark-plug hole. But the clearance on the diesel between piston and valve is so close, I'm pretty sure you can do it in the car.
Title: Blue smoke
Post by: burningchrome on February 20, 2009, 06:27:56 am
That clarifies things for me. Though shouldn't I be able to tell TDC by looking at the camshaft?
Cheers,
Etienne
Title: Blue smoke
Post by: burn_your_money on February 20, 2009, 02:30:40 pm
Check your timing. If it's off enough the car will actually smoke blue. Mind you it's more likely to do it all the time rather then just some times, but it's easy and cheap/free to check.
Title: Blue smoke
Post by: Rabbit TD on February 20, 2009, 08:19:20 pm
Quote from: "burningchrome"
That clarifies things for me. Though shouldn't I be able to tell TDC by looking at the camshaft?
Cheers,
Etienne



There is a mark on the cam gear on the inside edge at the top when the engine is at #1 tdc.  That means you can do cyl. 1 and 4 after removing the cam but then you have to rotate the crank 180 degrees to put #2 and #3 at top dead center.
Title: Blue smoke
Post by: burningchrome on February 22, 2009, 06:10:42 pm
So I replaced my return fuel line hose and there is still a sheen of diesel on the front on the IP. I believe it now to be coming from the "breather hole" located over  the banjo bolt for the fuel return line. I popped off the little rubber redirection hose and there was a pool of diesel in it. Any ideas what the problem is?
Cheers,
Etienne
Title: Blue smoke
Post by: burningchrome on February 23, 2009, 09:23:04 pm
bump
Title: Blue smoke
Post by: Vincent Waldon on February 23, 2009, 09:56:41 pm
http://www.vwdiesel.net/phpBB/viewtopic.php?t=12637&highlight=leak+lda

(searched for "leak" and "LDA") :wink:
Title: Blue smoke
Post by: burningchrome on February 24, 2009, 07:06:58 am
Thanks. The term LDA is a new one to me.
Cheers,
Etienne
Title: Blue smoke
Post by: Vincent Waldon on February 24, 2009, 07:55:32 am
Quote from: "burningchrome"
Thanks. The term LDA is a new one to me.
Cheers,
Etienne


Yup, diesel folks have a language all their own.   :D