Opinions on gear/engine match

[David Wesner]

Just bought a workboat with an older JWAC 6BTA, 250. It has a velvet drive 72C gear, can I expect issues down the road and what would a Heavy Duty replacement gear option be. Presently have a drive saver in line, so there is an 1.5″ or so extra length available if needed.

David

Topic

[David Wesner]

10-4

[Tony Athens]

You are wasting your time adding an oil filter.. If you want to improve the gear life, Upgrade to Mubilfluid 424.. The more we use it the more we like it..

Tony

[David Wesner]

Just went through a rebuild of a BG72C velvet drive. Flushed cooler and lines as best as I could. Getting ready for install and running. I have been contemplating the benefits of adding a 30micron ? filter to the outlet of the oil cooler. Best thing I came across is a hydraulic filter. Am I wasting my time or are there real benefits to doing this?

I’m looking to install and test run today. Any comments good or bad are welcomed. Thanks

[David Wesner]

It’s off. Aerokroil is awesome. Some help with a ball peen hammer and a small slide hammer.

[Tony Athens]

Lots of KROIL, a hammer, more KROIL, and internal puller.. Next time, assemble with lots of AlcoMetal lube between all touching surfaces..

Tony

[David Wesner]

It's dead.

Well, as expected…..lost the gear today. Brought it into marine gear shop in Fairhaven. Great bunch of guys that seem very knowledgable.

Their opinion was that the BG72C was borderline for the 250 cummins. I asked them what was a good replacement….they mentioned a MG506 or a MG507, the MG506 being preferred. Only thing is that the MG506 is about 5″ shorter, so a new shaft would be needed . I do not want to shift the engine aft for a couple reasons, so this would be best.

Some other info: they also believe that just idling around is worse for the gear than running at mid to upper hp. At first I thought this was counterintuitive. Their point being that the gear sees more stresses from the damper plate and power pulses from the engine. The longevity of these BG gears did not sound impressive.

I’m going to get this BW gear rebuilt and be on the lookout for a good MG506.

Presently removing the drive plate for inspection. Having trouble removing it without getting too rough. Any help or tricks would be appreciated.

[Tony Athens]

Your question is way to open ended……..Basically not much replaces VD other than another VD, unless you want to reconfigure things..

They are still available as new..

Tony

[David Wesner]

I’d rather not post a picture because it is a bit embarrassing at the moment. The question really is what are expectations and replacement options for the velvet drive. Engine s/n is 44239031.

David

[Tony Athens]

‘Just bought a workboat with an older JWAC 6BTA, 250. It has a velvet drive 72C gear, can I expect issues down the road and what would a Heavy Duty replacement gear option be. Presently have a drive saver in line, so there is an 1.5″ or so extra length available if needed.”[/i]

David,

I must admit, you really have me on this one.. You bought a “work boat” with an older 6BTA 250 and a BW gear.. I really have no clue to what you have or what you are asking or want to accomplish.. .. An older 6BTA 250 – from the 80’s , 90’s or ?? Post a serial #..

Why not put “OUR EYES” in your engine room and on your boat, and then tell us exactly what you you want to do…. Good digital pics will really help us help you along with the verbiage needed that goes along with the pics….

Tony

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