Smoky when cold.

[wrinx]

Will you use 360 degree bearings now?It will help the turbo to last longer

How does a 360 degree bearing differ from a normal bearing?

Not bothering with a 360 bearing as I want to upgrade the turbo eventually, so just want it working for now

Jack, the bearing can be seen below, it has 90degrees cut out to allow for oil flow I think. So a 360 will be complete...but still allows the oil to flow!

The 270 bearing has three small raised areas, equidistant on the bearing, which act as bearing surfaces....I wonder if the 360 has a bearing ring all the way around, or more bearing surfaces??? nyway, they are reckoned to be a "worth doing" modification.

wrinx

[wrinx]

Turbo is back together...

Back in the vice, replacing the split ring


Replacing one bearing and new circlip


Second bearing and circlip


Replaced on the shaft and pressed down to click over the spring clip


Bit of lube and new sealing ring, before placing the new 270 bearing



Placing the impellor base (or whatever it's called!), another gentle push to go over the split ring


Replacing the impellor, ensuring the alignment marks are in the right place and placing new gasket (around the outside circumference)


Bolting the housing down


Bolting the other end back on


The finished article


I'm not that convinced it will last much longer. There's still some sideways play in the shaft so it must have worn more than I thought

Anyway...it was worth a go!

wrinx

[cuore_sportivo_155]

there's always some sideways play in them, even new... the play needs to be replaced by an oilfilm while the turbo is spinning...

EDIT: by sideways i presume you mean radial?

[wrinx]

I was thinking the same last night...needs ot be some room for oil!

I can move the turbine and shaft a fraction, on it's axis....I think that means radially???

There is no forward and backward movement, which is trying to push the shaft through it's bearings, pressing against the 270 thrust bearing....does that make sense?

wrinx

[cuore_sportivo_155]

in the direction of the axis there shouldn't be movement (think that's axial play ), and away from the axis is radial

[cuore_sportivo_155]

did you thoroughly check the oil feed and return to see if they aren't gunked up aswell? especially the return is critical... also, the swarf metal is in your oil and filter, and ofcourse on the bottom of the oil pan...

[wrinx]

So the play sounds normal then...?

Oil pipes are fine and I will be doing an oil and filter change anyway.

wrinx

[mindus]

Looks like you know what you are doing, but, as far as I know, the job is useless without having the whole set being re-balanced (on a balancing bench with as close to normal working rpm (of turbo) as possible). This is what cost money in a turbo renewal but this procedure is vital for the turbo to last long (besides that the reassembly job must be done in a very clean environment).

However, the whole process is interesting
Good luck on this

"Vertical" play is ok, but there should not be any axial play (longitudinally the shaft/axis)

[wrinx]

Yeah, I'm aware the turbo should be put on a balancing rig to check....but, if all the bits are put back how they came off (marking as you go) then it should, in theory, be ok....ish....kinda....hopefully!

Seriously, I read a thread (possibly on FCCUK) from a guy who just used one of these kits and said he had no problems....as for the "very clean environment", my garage cannot be described as clean so we'll have to see

wrinx

[wrinx]

in the direction of the axis there shouldn't be movement (think that's axial play ), and away from the axis is radial

"Vertical" play is ok, but there should not be any axial play (longitudinally the shaft/axis)

I think we're on the same lines....in the picture below, if I hold the brass nut on the end of the shaft I can move it left, right, forwards or back...by about 0.5mm all round. However, there is no up and down movement at all.



wrinx

[wrinx]

...could you weigh the fan and shroud for me if they are still off the car?

No problem....these are not 100% accurate as our scales didn't like such small amounts

Fan - 3kg
Shroud - <2kg

The whole lot was 4.8kg.

wrinx

[mindus]

I think we're on the same lines....in the picture below, if I hold the brass nut on the end of the shaft I can move it left, right, forwards or back...by about 0.5mm all round. However, there is no up and down movement at all.

Yes, that's what I meant, it's good then.
Even my brand new ball bearing has a little of that non-axial play

[wrinx]

Excellent...thanks for confirming

wrinx

[wrinx]

Putting the turbo wastegate actuator on tonight and I noticed that the arm has some play at the wastegate end....so I turned the turbine housing to adjust it.

If the play was there before I dismantled it would the wastegate have been slightly open all the time or would the exhaust gases hold it shut?

wrinx

[Evodelta]

I don't know the answer to your question, but what you are adjusting is the 'base boost'. I believe some chips have different base boost settings and it needs setting up before you put the turbo back on. Is it .6bar on your car? It needs to be set with a pressure guage on the WGA so that is just starting to open the WG at whatever your base boost setting is.

[wrinx]

Not sure I explained it very well....I haven't adjusted the tension, merely set the WG arm so it doesn't allow the WG to rattle about.

wrinx

[Evodelta]

By turning the housing you will have adjusted it and by not testing it you will not know what your base boost is set at.

[wrinx]

Mmm, more explanation needed for me please...why would turning the housing have adjusted the BB?

wrinx

[Evodelta]

By putting more or less tension on the WGA you are altering the base boost.

[wrinx]

I haven't adjusted the tension///

By putting more or less tension on the WGA...

I'm still not explaining it very well....the end of the arm (the hole) was worn, allowing the WG to move about, without the WGA arm moving. So, I've moved the housing just enough to take up the wear and hence the movement in the WGA arm.

The WG doesn't rattle now but I made sure it has the tiniest bit of movement to ensure there wasn't any extra tension placed on the WGA.

Does all that waffle make sense?



So, as far as I'm concerned I haven't adjusted the tension...hopefully!

wrinx

[AlfaJack]

AFAIUI, as you have taken up a tiny amount of slack out of the rod, the movement of the arm from the WGA will be the same at the WGA end but the movement at the WG end will happen sooner as there is less slack - this will mean your base boost will drop slightly as the WG is opening sooner as the rod is being pushed at the same rate as before but its now straight on to the WG instead of overcoming the slack and then pushing on the WG.

I will be surprised if that makes sense to anyone. Not ever sure I understand it now

[wrinx]

I know what you mean Jack as I had exactly the same thought after I'd typed my previous post...but the difference will be a mere fraction of a second.

The other way of looking at it is that it could be back where it should have been in the first place (presuming the wear is from that side of course!!!

At the end of the day it will require the same amount of air pressure to move the WG and now hopefully the WG isn't flapping about losing pressure...unless the exhaust gases held it in place as per my original question

I could have got this all horribly wrong though... :shock:

wrinx

[AlfaJack]

Yeah I expect the difference will be so tiny it will never be noticed.

As for the wastegae flapping around, I am pretty sure it is held shut by the exhaust pressure.

[Evodelta]

Yes I agree with what you have done and your explanation now. I didn't know whether you knew if this is how you adjusted the BB or if you had gone too far or not - that was my reason for posting, It's been a long week and I was practically nodding off so kept it short!

The earlier versions of this engine had adjustable WGA rods, but were discontinued from the Evo 2 onwards.

Still, the same warning applies, If you are rebuilding a turbo you would set it correctly as matter of course, it is akin to putting back on your soiled Y fronts after cleaning yourself off from accidentally following through.

[wrinx]

Nice mental image....messy

wrinx