0M 603.971 Cold Starts, right up Then: - Page 2 - PeachParts Mercedes-Benz Forum

zloca944 · #16 10-24-2018, 03:59 PM

No,but you must leave computer so that can control idle(ELR) and not to drop RPMs when you turn on AC.

Uncle Benzz · #17 10-24-2018, 10:40 PM

Where did you get block off for egr? Do others models fit?

Quote:

Originally Posted by zloca944

On my W140 603.971,I blocked off EGR,and changed the vacuum operated wastegate actuator with one from older 603 that are controlled with pressure.No problems from then,no EGR junk in intake and full boost

.If you want to try EGR blocking and do not want to change wastegate actuator for the test,you can put a hose from vacuum pump directly to the wastegate actuator,but you must be careful because then you do not have overboost protection

.

zloca944 · #18 10-25-2018, 06:15 AM

I made it myself from Aluminum plate,and placed it between EGR and Intake manifold.Basically,with this setup I am using where the boost is controlled with pressure actuator no need for block off plate since I unhooked vacuum hose from EGR and it is always closed,but I made a block off plate already and I used it.

Uncle Benzz · #19 10-26-2018, 06:22 PM

Gents, I may have another issue adding to the other. I spin the impeller on the turbo its not free. It spins while idling but is not free. Seems to be tight. The shaft play is nil but maybe a bearing is binding or the hotside is coked up? Thoughts?

vwnate1 · #20 10-27-2018, 12:28 AM

I too have noticed this, older loose and floppy turbos have almost zero drag but every time I find one that's snug, it takes a few inch pounds to get it spinning by my fingers .

? How much is correct ? .

If I twirl it by my fingers, should it slow down and stop or halt as soon as I let go the nut ? .

TIA,

Diseasel300 · #21 10-27-2018, 10:28 AM

The clearances in the turbo bearings are very tight so there will be some drag if you spin it by your fingers. It shouldn't be stiff, but it shouldn't free-wheel either. If you spin it by hand and it doesn't stop pretty much immediately, you know it's very worn. If it feels stiff to turn or its difficult to move just by turning the threaded part of the shaft, it's probably coked up.

Uncle Benzz · #22 10-27-2018, 11:08 PM

So it's best to remove and check hotside for coking. Any good way to clean it?

Quote:

Originally Posted by Diseasel300

The clearances in the turbo bearings are very tight so there will be some drag if you spin it by your fingers. It shouldn't be stiff, but it shouldn't free-wheel either. If you spin it by hand and it doesn't stop pretty much immediately, you know it's very worn. If it feels stiff to turn or its difficult to move just by turning the threaded part of the shaft, it's probably coked up.

Diseasel300 · #23 10-27-2018, 11:27 PM

The bearing and piston ring will be what's coked up and causing the drag. At that point, you've got the turbo completely apart and time for a rebuilt. There's no "quick answer".

vwnate1 · #24 10-27-2018, 11:34 PM

Quote:

Originally Posted by Diseasel300

The clearances in the turbo bearings are very tight so there will be some drag if you spin it by your fingers. It shouldn't be stiff, but it shouldn't free-wheel either. If you spin it by hand and it doesn't stop pretty much immediately, you know it's very worn. If it feels stiff to turn or its difficult to move just by turning the threaded part of the shaft, it's probably coked up.

THANK YOU !, needless to say, this is *exactly* what I wanted to hear after having overhauled my turbocharger .

I find these easy to spin ones in junked cars all the time and wonder :

A. : will it spool up faster (say below 1,800 RPM)

-and-

B. : will the freer spinning one cause that annoying bue exhaust oil smoke ? .

FWIW, the passage between turbo and intake manifold is OIL FREE now, I am well pleased .

vwnate1 · #25 10-27-2018, 11:42 PM

" There's no "quick answer" "

Yes, there is : take the damn thing apart, diagnose and fix it ~ they're not very complicated, I was sure I'd ruin it but it was dead already so I gave it a go and it worked out well .

Uncle Benzz · #26 10-28-2018, 07:34 AM

Rebuild kits who sells the correct one for T3 Garrett ? Any upgrades for it, T3/T4 ?

Quote:

Originally Posted by vwnate1

" There's no "quick answer" "

Yes, there is : take the damn thing apart, diagnose and fix it ~ they're not very complicated, I was sure I'd ruin it but it was dead already so I gave it a go and it worked out well .

Diseasel300 · #27 10-28-2018, 10:28 AM

Quote:

Originally Posted by Uncle Benzz

Rebuild kits who sells the correct one for T3 Garrett ? Any upgrades for it, T3/T4 ?

Try the GpopShop. That's where I got my rebuild kit from. You can upgrade to the 360˚ thrust bearing and the stepped-gap piston ring for the turbine side. The 360˚ is kinda "meh" in my opinion, but the stepped-gap ring is a must on an old turbo.

They warn on their site (and in their literature) and I'll echo it here: Disassemble your turbo BEFORE ordering parts and make sure the gaps and clearances are in spec. Max side clearance on the piston ring gap is .003" and mine was at .009" (and that was with the new ring fitted!) so no rebuild kit was going to cure it's oil consumption issues. I sourced another turbo and used it as a parts donor.

Uncle Benzz · #28 10-30-2018, 02:43 PM

This sounds best so far......

Quote:

Originally Posted by zloca944

On my W140 603.971,I blocked off EGR,and changed the vacuum operated wastegate actuator with one from older 603 that are controlled with pressure.No problems from then,no EGR junk in intake and full boost

.If you want to try EGR blocking and do not want to change wastegate actuator for the test,you can put a hose from vacuum pump directly to the wastegate actuator,but you must be careful because then you do not have overboost protection

.

R.Diesel · #29 10-31-2018, 07:37 AM

Quote:

Originally Posted by wwii

I can't confirm but I also had this impression. I must have gotten that impression by reading something either in my manual or in a forum (maybe in the w140 forum at benzworld.org - not many diesel ppl over there but there are some). What I recall is that when the computer asks the egr valve to operate it expects to see a change in intake pressure and if it doesn't it thinks there is something wrong with the boost pressure (P2) control loop and dumps the boost pressure - or maybe something more sinister like if you mess with the egr we're not going to let you have boost. I haven't tried it yet, it's near the bottom of my priority list, but if I can find where I read that I'll add a post.

I've also seen posts of putting a bearing/bb/steel ball in the tube to block it.

If you try it please post your results.

What about crankcase pressure and blowing out oil seals?

Diseasel300 · #30 10-31-2018, 10:03 AM

Quote:

Originally Posted by R.Diesel

What about crankcase pressure and blowing out oil seals?

EGR is Exhaust Gas Recirculation. It has no effect on crankcase pressure since exhaust gas doesn't route through the crankcase (except for blowby gasses obviously, which are routed through the breather system).