Author Topic: Turbo seal / thrust bearing shot? (Read 9033 times)

gamber · « **on:** April 29, 2007, 09:34:59 pm »

Recently bought a 85 Jetta TD, engine code "H" from the VIN

During my pre-purchase inspection, noticed dirty oil. Thought, quick oil change and all is good. Not the case. I commute 1200 km a week and change the oil weekly. The oil use is roughly 1 litre / 1000 km, and at these now weekly changes the oil is BLACK. I am suspecting turbo seal and/or thrust bearing.

Exhaust is clean when warm. Very little smoking on cold start or acceleration until engine is up to temp.

Am I on the right track? Any other thoughts here?

jtanguay · « **Reply #1 on:** April 29, 2007, 10:40:55 pm »

have you ever driven a diesel before??? if you can keep your oil from going black after a week.. hats off to you! (the harder you push your motor, the more black smoke will pour into the oil...) 1L/1000km isn't that bad at all... you will find that the harder you drive, the more oil you burn...

i'm going to be installing a bypass filter on my jetta this summer... filters out the soot!

www.fs2500.com

Doug · « **Reply #2 on:** April 30, 2007, 03:52:02 am »

Jt's right. Your oil is supposed to be black. That is the detergent package keeping the carbon generated by blowby in suspension where it will not precipitate out to cause problems. It sounds from your description that the engine is performing alright. Leave well enough alone and drive it. Change out the oil every 3000 km or so with a quality diesel rated oil.

burn_your_money · « **Reply #3 on:** April 30, 2007, 06:07:08 am »

Alot of that oil usage is probably from leaks. I find that if I fill my engine to the top with oil the first half of it is gone within 200 kms, the last half of the dipstick will last at least another 1000 kms though.

As mentioned jet black oil is normal, as soon as I start my car after an oil change it's black

gamber · « **Reply #4 on:** April 30, 2007, 08:17:39 pm »

Thanks for the input - was paranoid!

gamber · « **Reply #5 on:** April 30, 2007, 08:22:53 pm »

amazing thing though, each time I change oil, it runs better! any feed back here?

Suggestions for moderate mods for improved performance?

Love to update the suspension - any ideas?

burn_your_money · « **Reply #6 on:** April 30, 2007, 08:30:27 pm »

Sounds like you have alot of soot in the system, look into www.AUTO-RX.com I'm planning on buying some soon... maybe even tonight

QuickTD · « **Reply #7 on:** April 30, 2007, 09:16:38 pm »

Quote

I commute 1200 km a week and change the oil weekly.

Changing oil every 1200km is a recipe for very rapid engine wear. While regular oil changes are required, very frequent changes are not necessarily better and may in fact be harmful. Engine oil does not perform at its best until it has a few thousand km on it. Engine wear is generally highest immediately following an oil change due to factors such as detergent wash and the high total base number or alkalinity of new oil. I would suggest you leave it in at very least 5000km, better still run it for the VW recommended 10000km if your travel is mostly highway miles, your engine and your wallet will thank you.

jtanguay · « **Reply #8 on:** April 30, 2007, 11:47:35 pm »

check out www.fs2500.com video's.. you will be amazed! i'm installing one on my m-TDI! oil change intervals of 25'000km is possible.

the extra performance from the oil is attributed to the fact that there is next to no foreign particles flowing through the oil... remove them, and you can increase mileage, and decrease overall wear on the motor!!

my last oil change wasn't black until i put around 100km on it... good synthetic, and not flogging the engine is the key!!!

i too had to get used to oil turning black fairly quickly when i bought my first diesel... once you go black (oil) you don't go back! :roll: :lol:

Doug · « **Reply #9 on:** May 01, 2007, 04:08:06 am »

Repalce rings and valve guides and you will be amazed that the oil will not be as heavily laden with soot as quickly as before. In fact it seems to stay more or less clean for several hundreds of kilometres.

gamber · « **Reply #10 on:** May 17, 2007, 10:36:36 pm »

so what is the easiest way to re-ring? read somewhere that it can be done easily, just cannot find the link again

Doug · « **Reply #11 on:** May 18, 2007, 03:29:04 am »

I am not sure that there is an easy way or a hard way. Most of the time is spent hunched over the motor assuming that you are doing it in the car. Get a book like the Bentley, read it till you are sick of reading it, then read it again. Break out the tools and start diassembly. With the head off at that mileage make sure that you replace valves and guides. Always hone cylinders with a brush hone. Install new rod bearings as they are cheap. Also replace the glow plugs as they are easily accessible. The last time I left the manifolds and turbo attached to the head so that I did not disturb the gaskets. It is quite a lift to get things back in place but if you had a friend to help it would to go easier. That was the hardest part for me as the slope of the head makes it want to slide back before you get the gasket and bolts positioned properly.

Or you could pay somebody to do it for you.....

jimfoo · « **Reply #12 on:** May 18, 2007, 05:55:55 am »

Quote from: "Doug"

That was the hardest part for me as the slope of the head makes it want to slide back before you get the gasket and bolts positioned properly.

Or you could pay somebody to do it for you.....

That's where either using ARP or Raceware studs helps, or cut the heads off a couple of the old head bolts, cut screwdriver slots in them, and thread them in to help position the gasket and head.

burn_your_money · « **Reply #13 on:** May 18, 2007, 05:58:22 am »

Quote from: "jimfoo"

That's where either using ARP or Raceware studs helps, or cut the heads off a couple of the old head bolts, cut screwdriver slots in them, and thread them in to help position the gasket and head.

Just be carefull not to gouge/scratch the head when you are lining everything up.

Doug · « **Reply #14 on:** May 18, 2007, 07:58:58 am »

I believe that the Bentley suggests using wooden dowels inserted into the bolt holes in the block to assist in the alignment. This is the same idea as the head bolts cut off and slotted on the top. This works if the head is stripped of manifolds and turbo. I found this did not work well for me because of the height that the head had to be lifted to with a full arm extension in order to reach into the engine compartment. This would be a lot easier with a second person assisting. With a new head gasket and the surfaces clean and dry it is possible to gently move the gasket and head around until the holes line up correctly. If I did it with success then you can too.