Perkins 4108 gearbox identification

[jewt]

Beta is okay but keep the velvet drive. SDTAY AWAY from Volvo they are POS!

just sayin',

Jewt
S/V Bifrost

still on the hard in Beaufort

[FPNC]

That is a Borg Warner gear. 1.91:1 ratio. Either a 71c or 72c.

Your engine turns CCW. The gear is marked as a CW output shaft rotation in forward. The only 71c or 72c B.W. gear that I know of that turns CW in forward with a CCW input is the 1.91:1 ratio gear.

[Compass38]

Thanks for everyone for taking the time to respond. Much appreciated!

[tom jones]

Skipper: read your comments in the Cruising Forum. We are an older couple in SW Florida we completed a 4 yr restoration of our a 43ft Brewer cutter rig engine was a Lehman SP90. Enroute our boat got hit in a marina at Brunswick GA while we were away. long story to say the engine room partially flooded. now we are facing rebuilding cost estimates are running $10k+, above our budget.

you mentioned rebuilding quite a few Perkins and i was wondering if you are aware of any used working Perkins 4108s for sale and how difficult it would be to replace the lehman with a Perkins. As usual i will be doing most of the grunt work and leave the skilled work to a mechanic . Thanks in advance for your help
Tom s/v Blue Trust tj5035@gmail.com

[Dmc1]

Originally Posted by coopec43

Perkins don't make gear boxes so as OldCal46 says it is a Borg Warner.

There is a 1.9:1 and a 2.1:1 but one turns clockwise and the other anti-clockwise so that may help to identify the box.

My opinion is it is unlikely to be either of them and more likely a 2.5:1 in a yacht the size of a 38ft boat.

Clive

I have just bought a boat with twin 4108 engines.the surveyor mentions that starboard prop is 17.5x10 and port 17.5x12 and are in good condition.im concerned they should be matched or could this be to do with gearbox ratios.any help will be much appreciated