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Thankyou. I will start ringing around wreckers in the morning. I suspected that might be an option but didnt know which truck models would have been compatible. I will let you know how I get on.

The intermediate plate is okay it's the housing that's the problem. The holes don't line up with the holes in the block. They even resorted to trying to drill new holes, one of which went through a water gallery which they blanked off. Still, there were only 4 bolts holding the whole shooting box together.

My apologies Tony I used the wrong terminology. The existing housing did accomodate the flywheel and stubshaft, with the intermediate plate,that included a plunger type oil pump bolted to it, feeding oil through an internal gallery to the central bearing mounted on the stubshaft. That housing was for a Commodore and basically fitted where it touched. That will all have to be replaced with a new setup. Lancing Marine Marine still make a housing for the 4/98 and they are sending me a template to see how well or not it mates up to the back of my motor. They mated it to a velvet drive but should also fit PRM okay. Just went into the back of the boat and took a quick pic of the intermediate plate and oil pump.

Thanks for that Tony. I have the possibilty of a PRM 307?. Was rebuilt and then did less than 100hrs but has been sitting in a container for about 5yrs. Cost £750. Still have to find bellhousing, make adapter plate and lengthen propshaft, because the PRM is about 12" shorter than old mechanical box but could well be the way to go. Would certainly make maneuvering in and out of my marina berth a lot easier. I will continue dismantling the old box ,just for the hell of it, and possibly will be able to give it away for spare parts or something.

Ain't that the truth. My late father was a diesel engineer. Trained in the RAF during the the war. Should have paid more attention and asked more questions.

Hi Tony. Absolutely spot on. Inspected the whole thing and the reduction box will need to be removed to continue dismantling. Will require a puller and a bigger socket than I have to take coupling etc off the back. The backing plate for the brake drum has moved back so I can see the clutchplates but need to complete the aforementioned before I can properly inspect them. Learning a lot more about mechanical gearboxes than I ever wanted to know. Thanks to input from the forum I'm getting there. I suspect that I might be heading down the hydraulic route as the probable engineering bill is mounting up. The delta lockdown here is not making things any easier and with Christmas looming and summer holidays thereafter it might be a long winded process. Never mind I didn't expect to be using her this summer anyway.

Funny you should mention that. Yesterday I found a bmc commander for sale on a local trademe site and low and behold one of the pics showed an owners workshop manual for a Newage Commander engine. Ive sent him a cheeky question asking if it has any mechanical box info in the back of if. That particular engine has a velvet drive box with a Lancung Marine badge on it.

Thankyou Tony. You are absolutely correct. The box does have a plunger type oil pump on an intermediate plate with a central bearing. It was this bearing that took the 1st line of abuse because the stubshaft was at least 25 thou out. It took a 40ton puller to move it. The brake drum is proving similarly recalcitrant at the moment and resisting all efforts to shift it. An ongoing saga I fear. Will hopefully get easier once I obtain a workshop manual now I have gearbox id.

Hi Tony. Thanks for your info. On reflection the damaged gear is missing 1/3 or less of the operating surface of 1 tooth. 2 gears have nonexistent bushing and others badly worn. I have a local machine shop , run by an expat Yorkshireman who is very good, but as he said today the price of bronze is going through the roof. Still need to get the rest of it apart to fully assess damage before I can make a decision. At least I can now look for an appropriate manual. Thankyou.

Hi Tony. Have been messing around for 3 days trying to get photos onto the site. Finally. As someone suggested I also contacted Lancing Marine who suggested it might be a Newage. There was so much rebranding going on in the day that it all gets a tad confusing. If I can identify the box I may be able to get a service manual for it . At the moment it is fighting us every step of the way. It definitely does not want to be dismantled. As you would expect there is a fair bit of wear in the gear bushings and 1 of the gears inside the brake drum has a broken tooth. I presume the carnage list will increase as we progress. Very much appreciate your input and help. Forgot. All casting marks/parts numbers, internally and externally on the gearbox start with AEH.

I have created albums (8 pics) on: Google Photos, Flkr and Thumbsnap. All have the album title: BS motor & gearbox. Hopefully anyone registered and using one of these apps will be able to view them.

Thankyou Tony.

Thankyou all for your help and interest. I have uploaded an album of photos onto thumbsnap but have been unable to share them. I have cotacted them for a 'how to' but so far have not had a reply. Hopefully willbe able to do so shortly which should make things a lot easier.

I have a 60yr old motor sailer originally powered by a BMC Commodore (circa 1957/8) mated to what I believe to have been a Parsons reversing gearbox. Subsequently some genius decided to repower it with what I think maybe a 4/98 Leyland. The gearbox held to the motor by 4 bolts! It fits where it touches. Having struggled to get it apart I've found that the stub shaft is 25thou out and the brakeband has worn a groove in the drum. There is no sign of a brake band lining. Mathway Marine suggested it might be a Morris Vedette gearbox. I didn't know BMC made their own marine gearboxes. Could it be a rebadged Parsons? I would like to get hold of a parts diagram and probably a manual if I can gind out what it is. Did anyone ever marinize a 4/98 Leyland. If so I might be able to purchase the correct bellhousing rather than having to have one made. Any advice greatly appreciated.