# Anyone have any experience with EMD marine diesels ?



## Derek Roger (Feb 19, 2005)

2 stroke medium speed ; Any experiences with cracking of the turbo charger casings ?

Cheers Derek


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## makko (Jul 20, 2006)

I have come across EMD V20-645's Derek but have not heard of this particular problem. It is most likely our USA counterparts will have more on this.

Regards,
Dave


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## Derek Roger (Feb 19, 2005)

Thanks Dave . The engine was originally for locomotives and then was made available for Marine use . Used quite a bit in the offshore and tug boat business so should have a lot of history .


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## makko (Jul 20, 2006)

Hi Derek,
You can see their heritage as they are skid mounted and fully self contained. Very low height overall of the engine. They have air start motors driving the flywheel and one I saw had an external exciter driven by a belt from from an extension to the camshaft!
Rgds.
Dave


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## surfaceblow (Jan 16, 2008)

The only EMD's that I worked on had Roots Blowers installed. One problem with the Roots Blowers was if you had an over speed trip from the prop coming out of the water the air dampers would close causing the shaft seals of the Roots Blower would suck in allowing air to continue entering the engine. 

Only had a generator Turbo Charger casing fail due to erosion in the cooling passages. Found the cooling water in one of the cylinder's when blowing down the engine. 

Joe


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## paulm (Oct 22, 2007)

Seen t/c's fail a bumber of times - with Blackstones i.w.o of cooling passages - B.B.C. BLOWERS - Any more info required please just mail me - Kind Regards,
Paulm,


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## Derek Roger (Feb 19, 2005)

Thanks for the feed back ; when I have more information on the failure I will share it with you .At this time all very cloudy with no feedback . |I am trying to assist a friend who is not an engineer who has been asked for an opinion .


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## makko (Jul 20, 2006)

Look forward to the update, Derek. In my experience it is either the bearings or erosion.
Rgds.
Dave


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## BLACKMIRRLEES (May 1, 2014)

*Blackmirrlees*

Hi, havent had any experiences there, but have seen huge cylinder bore wear rates on all the EMD two strokes, 567, 645 and 710, when used with high sulphur content fuels without Porous Chromium Plated cylinder liners being installed.
It is nothing to have the 9 1/16th bore 645 and 710s with 90 thou on the diameter ring steps, and 140 thou on the diameter wear in the Port Relief Zones when used with cast iron liners. Even the HUB ( laser hardened ) liners suffer excessively. Needless to say there is considerable " ring flutter " through the P.R.Z.


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## steamer659 (Mar 18, 2009)

I have a has a lot of experience operating, repairing and overhauling the 645's- E & L's , ranging from 12 cylinder to 20 cylinder, with Roots Blowers and T/C's.

One should remember that the T/C's on the E4's and E5's were combined gear driven or gas driven- on a 900 RPM engine, the gas kicked around 720 RPM- 75% load and "out sped" and over running clutch in the T/C gear drive. If you operated a lot in the 720 RPM range, this would cause the over running clutch to repeatedly engage/disengage- which sent pulses through the whole affair, not to mention the accelerated wear on the over running clutch. We deliberately stayed away from this load range at all costs.

As genset engines, I loved these engines as well as the CAT 3606 & 3608. Although entirely different engines, they were both robust, reliable engines...
Used the engines as both gensets and main propulsion...

The "premium" cylinder packs with the "advanced" piston pin (wrist pin) bearings did not like zinc additives in the engine oil and would experience very high wear rates in the liner and running gear when a detergent zinc rich oil was used...


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## Derek Roger (Feb 19, 2005)

steamer659 said:


> I have a has a lot of experience operating, repairing and overhauling the 645's- E & L's , ranging from 12 cylinder to 20 cylinder, with Roots Blowers and T/C's.
> 
> One should remember that the T/C's on the E4's and E5's were combined gear driven or gas driven- on a 900 RPM engine, the gas kicked around 720 RPM- 75% load and "out sped" and over running clutch in the T/C gear drive. If you operated a lot in the 720 RPM range, this would cause the over running clutch to repeatedly engage/disengage- which sent pulses through the whole affair, not to mention the accelerated wear on the over running clutch. We deliberately stayed away from this load range at all costs.
> 
> ...


Thanks for that Steamer . The operation I am looking at has the problem according to the operators of too much clutch activity . The vessel has 710 model marine diesels and is being run at lower loads to try and reduce fuel consumption and as such the turbo does not kick in very much . In heavy weather with constant load changes in that range the blower is kicking in and out a lot . Damaged 3 to date and a 4th may be on its way out in my opinion . Have recommended they run at increased power to eliminate the problem .
I am also considering whether to have the clutch disengaged altogether and supply charge air at low loads by an electric driven blower . ( could be costly as I don't think EMD have that option at this time ) Thanks for your experienced input . Derek


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## Varley (Oct 1, 2006)

Derek, Our Tech Services Manager Dick Swindall always advocated electrically driven blowers (although this chapter of his afternoon story time illustrated the proposal with consequential DC breakers glowing red and held in, perhaps out, by broomsticks and chief engineers removing every other lamp in the passenger's saloon).

I might go one further step and power your electric blower from a shaft driven generator of some sort - so power required increases the main engine load as well. If used only for the blower then otherwise important 'constants' (near constants) of voltage and frequency can be extremely flexible.


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## Derek Roger (Feb 19, 2005)

Varley said:


> Derek, Our Tech Services Manager Dick Swindall always advocated electrically driven blowers (although this chapter of his afternoon story time illustrated the proposal with consequential DC breakers glowing red and held in, perhaps out, by broomsticks and chief engineers removing every other lamp in the passenger's saloon).
> 
> I might go one further step and power your electric blower from a shaft driven generator of some sort - so power required increases the main engine load as well. If used only for the blower then otherwise important 'constants' (near constants) of voltage and frequency can be extremely flexible.


The vessel has shaft alternators but they are dedicated to bow thruster required for docking .. Thanks for your input. Derek


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## Derek Roger (Feb 19, 2005)

surfaceblow said:


> The only EMD's that I worked on had Roots Blowers installed. One problem with the Roots Blowers was if you had an over speed trip from the prop coming out of the water the air dampers would close causing the shaft seals of the Roots Blower would suck in allowing air to continue entering the engine.
> 
> Only had a generator Turbo Charger casing fail due to erosion in the cooling passages. Found the cooling water in one of the cylinder's when blowing down the engine.
> 
> Joe


The 710 model does not have the roots option ; only the hybrid turbo with clutch to drive at low power until the turbine overruns the mechanical drive .


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## surfaceblow (Jan 16, 2008)

Derek Roger said:


> The 710 model does not have the roots option ; only the hybrid turbo with clutch to drive at low power until the turbine overruns the mechanical drive .


The EMD's I worked on was on a ship build in the late 1960's and definitely had Roots Blowers. I have a not so fond memory of climbing up to place plastic garbage bags over the air intakes to stop the engine after an over speed. Afterwards we had to replace the Roots Blower's seals and replace the fuel shutoff valve. We found brass filings in the filter. We also took apart the air damper to make sure they closed properly. 

The failed BBC Turbo Charger was on a Daihatsu Diesel Generator Set on the Marine Reliance still in over thirty years sailing it was the only casing failure I had witness. 

Joe


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