Cummins 6TBA 300 HP engine turbo oil leak

[Ferry bank]

Hi
We have a slight oil leak on one of the turbo bearing, can anyone recommend a repair company please?
Its a 1993 engine and the later engines are 330 HP does anyone know what was modified for the extra 30 HP ie. was it a larger turbo
Thanks

 

[Latestarter1]

Hi
We have a slight oil leak on one of the turbo bearing, can anyone recommend a repair company please?
Its a 1993 engine and the later engines are 330 HP does anyone know what was modified for the extra 30 HP ie. was it a larger turbo
Thanks

PM your engine serial #'s.

Do you have Walker Airseps?

Some pictures would be helpful, oil leaking from 6BTA turbos is very rarely turbocharger failure, once I have pictures of your installation I will explain everything.

Early 300 CPL's with Denso fuel pumps were somewhat different from later 315, 330 and 370 CPL,s which had Bosch P7100 fuel pumps, from early CPL 970 300 of the late 1980's to the later 330, 370 major hardware differences. All have Holset H1 turbochargers but slightly different models.

Do not be too keen to rip into your turbochargers yet, plenty of Holset agents out there ready to take your hard earned cash. Remember dependant on your competence with a spanner can be DIY job, putting a repair kit into a Holset H1 turbocharger costs no more than £80 and about an hours work.

Difference between 6BTA 315 and 330.........absolutely nothing, different rating conditions, 315 is a 40 Degree C test fuel rating and 330 25C fuel, smoke and mirrors stuff.

 

[Ferry bank]

Cummins engine

Thanks for your help, will PM the info later in the week
The oil is dribbling from the centre of the blades in the turbo towards the air filter

 

[Latestarter1]

Thanks for your help, will PM the info later in the week
The oil is dribbling from the centre of the blades in the turbo towards the air filter

I could write a book on on oil carryover on Cummins B Series.

The 'factory' Donaldson air cleaner is OK but was designed for a generator application and salt laden dam air is not friendly to this unit, if you are seeing a restriction compressor will pull lube past piston ring seals in turbo bearing housing. However could be oil carryover, suspect that you have older style band clamp on the turbo. Maybe 9 years ago, Cummins switched to a new Holset Turbo that used a clip to hold the air side housing on the turbo and there is often evidence of a drip of oil at the bottom of the housing and continues to this day......You see it mostly on the 6BTA’s 330 and 370 Diamonds and it follows very specific patterns, mostly related to the install of those motors.

First off, the air housing is not “sealed” per se, but only has a close machined fit between the removable snail and main body.. In many instalation air ventilation is marginal and with just “normal” blow-by, the velocity of the moving air within the engine room carries the blow-by thru the air cleaner to the turbo where the oil mist tends to accumulate.. Hi-angle installs, overfilled oil pans, Walker Air-Seps installed the “factory way”, all tend to amplify this oil accumulation in the turbo...................After a few hundred hours, (sometimes much less), this oil accumulation will become so excessive that it drips out the bottom of the turbo.

I have seen many turbo replacements done under warranty, only to see the same thing occur a couple hundred hours later? There was nothing wrong with the turbo -it was 100% accumulation of oil mist that just starts to drip afer the build up becomes large. You could have a bad turbo but in most cases that IS NOT the problem..........

How to solve the problem,It will vary from installation, but if ventilation is OK (or so it seems to be), then be SURE oil pan is not overfilled. Running 12 litres total system capacity is far better on some installation angles is far better than running at 14-15 litres.

If you happen to have a factory Walker installed the typical way Cummins does it, (with a low loop/liquid trap between the CC vent and the AirSep), fix it so it’s RIGHT, or remove the thing and install I can advise you on several designs which are far superior. Making the engine breathe from a quieter place than tappet side cover, for example the front timing cover is perfect.

In some installations when I know the turbo it right but are still plagued with this nuisance of oil carryover then talking apart the air side of the turbo at 300-500 hours intervals and cleaning it, is now part of NORMAL maintenance.. Nor more than maybe 2 hours once every one or two years, and no parts needed.