# Sulzer RLD90



## Cervelo4 (Apr 29, 2015)

New here so I hope this is the right place for this.
Since going to MDO ( marine diesel oil) the start of this year the engine has been showing huge liner wear 2 mm per 300 hours of run time.
All temperatures and pressures are normal, same as when we were running HFO.
Cylinder oil has been checked and rechecked, if anything we are over lubricating.
All cylinders - 5 - are showing the same wear.
Any thoughts?


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## Duncan112 (Dec 28, 2006)

Sulphur content of MDO will be low - leading to a residual alkalinity of the cylinder oil - overlubrication will make this worse which may speed up liner wear. Even so 2mm/300 hours is high I wonder if the timing needs adjustment as a higher peak pressure will increase the cir***frential ring force which may also speed up wear.


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## Cervelo4 (Apr 29, 2015)

The timing has been retarded to keep firing pressure at injection below below 30 bar.
The lower 3 rings are so sharp you can shave with them.
Liner temperature has increased since the use of MDO started but is usually below the 275 alarm point.
Jacket water has been lowered to 75c, with a 10 deg delta T with piston cooling.


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## John Cassels (Sep 29, 2005)

Buy an B & W ?.


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## steamer659 (Mar 18, 2009)

What type of cylinder oil are you using 40, 55 or 70? We shift back and forth from HS-HFO to LS-MGO, we use HT 70 for the HFO and HT 40 for the MGO.

Important to note that there's much less heat content in MGO than HFO....


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## steamer659 (Mar 18, 2009)

Also, how heavily loaded are you? Remember that the rack will increase just from the lower heat content on MGO. What temp are you keeping the Jacket water outlets at the cylinder?


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## BERRIET (Sep 17, 2007)

*Rlb 90*

Hello , 

is this a RLA , RLB , or a RND ?

was the water jacket and liner putted back in place correctly ? it looks like a misalignement ;are the liner and water jacket correctly seated on the engine frame ? were is the wear pattern? is it totally circular ? how does it look like ? 

Such wear seem to be a defective geometry , a mislanding of the piston liner assembly .
Is the piston correctly centered in the liner ? what about rubbing belts at the lower part of the piston skirt ? are they in good condition ? 

What about the stuffing box ? are the rings Inside in good condition ? is the stuffing box centered with piston rod and liner axis ? 

Crosshead was serviced ? any machining , or repair works one ? 

is the conrod sheel in good condition ? is such wear in the piston rings and liner , look at the big end conrod sheel.

Best regards , 

(Thumb)


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## makko (Jul 20, 2006)

The "lubricicity" od MDO is much lower than HFO. I would go for a study for which cylinder oil to use to compensate possibly. Also, if it is low sulphur, this might have a bearing on the exceedingly high wear rate. It might simply be better to return to HFO!
Rgds.
Dave


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## Varley (Oct 1, 2006)

Makko, surely that would be an issue for fuel pumps/valves rather than liners (and a matter of low Sulphur specifically). Can't find any description of an RLD.

Would 'fines' be as noticeable on a constant pressure fuel system? (first causing nuisance only after injection).


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## makko (Jul 20, 2006)

Varley,
I think both - Possibly the sulphur issue. Fines affect fuel pumps. Then vanadium affecting T/C's. There may be some fix but that might involve liners/rings etc. due to loss of sulphur lubricant.
Rgds.
Dave


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## alastairrussell (Jun 19, 2007)

You will have to get in contact with the supplier of your cylinder oil and explain your problem to them. They will then give you a different cylinder oil to use when burning your low suphur MDO.

In the late 1970's I once sailed with two different types of fuel on board with one being HO with around 2.5 % sulphur . The other fuel was a low suphur MDO which had been used for cleaning purposes in the refinery and was refered to as Industrial Diesel Oil. We had to change over to a different cylinder oil every time we changed over to the low sulphur IDO and vice versa. 

The reason for this was high liner wear if you did not use the correct cylinder oil for the correct fuel oil.

I can go into this problem further if I rake through all my very old sea going notes but I think it would be better if you contacted your lubricating oil supplier and got the latest info on the subject.


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## steamer659 (Mar 18, 2009)

I shifted my B&W KHIC S60MCC over to MGO yesterday morning, upon entering the North American ECA. Generally, we shift back and forth between HS-HFO and LS-HFO every ten days or so on board... The following "ground rules" would apply...

1) Proper Grade of the Cylinder Oil IS dependent upon the sulfur content of the fuel, you should be using a more alkaline, sulfur inhibiting cylinder oil for the 
HS-HFO, we use an HT 70 grade, this and a proper feed rate- roughly .95 or so.

2) Changing over from HFO to MGO is not generally a "pushbutton operation", 
engine load, fuel temps and viscosity are VERY important while changing over:
B&W cautions about changing the temperature too fast, especially going to MGO. We secure the steam to the FO Heaters while on HFO, allow the FO temp to drift down slowly to within 25 C of the MGO (but in any case not less than 75 C or higher than 20 CST at the viscosimeter. Failure to do this will score pumps, plungers and valves on the individual fuel pumps...

3) As of late, A LOT of the fuel around Holland and Belgium contains large amounts of "Cat Fines" left over from the cracking process within the distillate stocks used to blend RMG 380 cst fuel. If you're shifting over at very high load, and are using a 55 or lower grade cylinder oil when shifting from HS-HFO to LS
MGO, I would fear the worst....

4) The fact that ALL of the liners are exhibiting the same high wear rates, this would point to only a few directions:

Improper Cylinder Lubrication
Improper Water Jacket Temps
Incorrect Liner/Ring Installations

Hope that helps...


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## Tony Morris (Oct 7, 2006)

If anyone is interested here is a history of Sulzer designations. I would also suggest that the air cooler water separators should be looked at, if they allow the air to bypass the louvres then this causes very high wear very quickly, a common problem with the RTA.

Tony


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## marshynzs (Jan 5, 2009)

Possibly one of worst contaminents in combustion spaces are water particles in the fuel even after extensive purifying. I would at the next opportunity check your piston rings through the ports ,if you find a sort of gummy condition between the ring grooves then this would indicate to me that you have some water ingress with the fuel OR as Tony has mentioned water carry over from the charge air cooler.
One ship i was involved with had a severe wear problem over a 6 month period with several scavenge fires,on removing one piston we found the rings to ALMOST seized up and heavy deposits of destroyed lubrication residue there was also high liner wear from the previous readings One can never be 100% sure that purification is totally satisfactory To conclude i would check air cooler and take some samples from your purified service tank and check water content by any means available.
As you have the same problem on all liners i cannot believe you have incompatable liner/rings or that you have misalignment.Hope this may shed some light on the problem,be interested to hear about your results!!!!.


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