BMC diesel/ Parsons gearbox.

[David Hiley]

Thankyou for your time and effort Scottie. I'll keep on researching.

 

[scottie]

Thankyou for your time and effort Scottie. I'll keep on researching.

it’s a strange one and difficult to establish what the various lumps and bumps are for are there springs under the brass caps and hoe is gear selection done
Latestarter if he were still about might be best bet but it’s some time since he posted
what it’s not likel to be
parsons paragon Borg Warner anything Volvo

 

[burgundyben]

The gearbox looks very similar to a PRM Delta, although that epicyclic gear set in the front is unusual.

Have you asked the Thames Vintage boat club people?

 

[Flynnbarr]

You could try Steve Bil who now resides at Stanley and Thomas boatbuilders Windsor……(old school marine engineer who is extremely knowledgable)

 

[David Hiley]

Hi Scottie. Gear selector is mounted to a transverse shaft which is located aft and below the level of the casting marks which can just be seen in the side on pic. The brass caps are oil fillers.

 

[burgundyben]

Just a thought...

About 6 months ago I sold on ebay a completely worn out pair of 4/98's that had been marinised by Lancing Marine. They had belhousings by Lancing that acceped the Borgwarner Velvetdrive gearboxes. They were bought by Marine Enterprises. He might still have them.

I kept the PRM160C gearboxes. 2:1 reduction. I still have them but not planning to use them

Any Velvetdrive, PRM 'C' or ZF63 box would fit that bellhousing.

If you could buy one of my old Bellhousings to fit on you 4/98 from Sean at Marine Enterprises you would then have loads of gearbox options.

 

[David Hiley]

Hello Ben. Thanks for the info. Were your 4/98's automotive or industrial. That's where whoever did this insurance job screwed up. They thought yippie we'll stick this 4/98 in here then found the back of the block was different and bodgied it up. My engine has come out of a tractor or something and has substantial bolts holding the box to the block. There is no separate bellhousing on a tractor as far as I can ascertain. The gearbox bellhousing being cast in one piece and becoming, for all intents and pruposes, a structural part of the machine.

 

[David Hiley]

Hello Ben. Thanks for the info. Were your 4/98's automotive or industrial. That's where whoever did this insurance job screwed up. They thought yippie we'll stick this 4/98 in here then found the back of the block was different and bodgied it up. My engine has come out of a tractor or something and has substantial bolts holding the box to the block. There is no separate bellhousing on a tractor as far as I can ascertain. The gearbox bellhousing being cast in one piece and becoming, for all intents and pruposes, a structural part of the machine.

Yes I have been in touch with Lancing Marine, who unlike Thorneycroft , have been very helpful. I'm also up against the fact that I believe that Parsons etal had stopped making mechanical boxes before the 4/98 came into existence.

 

[burgundyben]

I dont know the history of mine, they'd been in the boat many years at least 15 of which were in commercial service, then she sank, I knew all of that, didnt bother at all with then, hooked them out and found a pair of Cummins to go in.

 

[bristoljim]

Yes I have been in touch with Lancing Marine, who unlike Thorneycroft , have been very helpful. I'm also up against the fact that I believe that Parsons etal had stopped making mechanical boxes before the 4/98 came into existence.

David - just out of hospital ok - I think your old box had the input gear bolted to the end of the crank with the flywheel running in oil - time to forget those boxes, paint flowers on it !.Head in the same direction as Burgunyben - the bellhousing I have is SAE5 & probably as his engines.Your existing drop down reduction puts shaft lower than crank so a drop down PRM 160 will be fine & if that is what Ben has you are in clover. Tractor engines based on vehicle engine often had heavier flywheels so there maybe a bit of work to do there.
So in summary - flat plate on rear of engine,ex BMC marine housing to SAE5,off shelf SAE5 to PRM adaptor.
Any pictures of back of engine on here ?

Jim

 

[Farmer Piles]

Hello Ben. Thanks for the info. Were your 4/98's automotive or industrial. That's where whoever did this insurance job screwed up. They thought yippie we'll stick this 4/98 in here then found the back of the block was different and bodgied it up. My engine has come out of a tractor or something and has substantial bolts holding the box to the block. There is no separate bellhousing on a tractor as far as I can ascertain. The gearbox bellhousing being cast in one piece and becoming, for all intents and pruposes, a structural part of the machine.

Quite right on the bell housing/tractor front. I use a 1976 Leyland tractor with that engine to launch and retrieve my boat. As you say, the engine and gearbox are effectively the chassis and load bearing and as such the gearbox and bell housing all one piece. One thing I would add is that the cylinder liners needed regular replacing in the tractors. New rings and liners was a regular task. They worked hard and did far more hours than a boat engine - 500-1000 a year - but maybe worth a look whilst it is stripped down.
Ron Greet Tractors near Totnes in South Devon is a great source of old and vintage tractor parts, new and S/H, and extremely helpful if you are after engine parts that are Leyland standard bits.
Good luck with it all

 

[David Hiley]

Hi Jim. Glad to hear your home and doing ok. Image shown is of back plate with startermotor installed. Drop down on original box was 4" so, as you say, prm would fit the bill nicely. Minor differences could be accomodated by going from solid to flexible mounts. Prm will be approximately 12" shorter, which will require some messing about.Pity to lose original box. Although only 60years old the boat is so well built it will last another 60, after I've finished giving her a refurb, and at some stage she will be a classic and somebody will probably want to put her back to absolute original. Mechanical boxes will by then probably only be in museums.
Flywheel is 16" diameter and doesn't appear to be the heavier one one would expect to find on a tractor. But bearing in mind the standard of engineering carried out anything could have happened in that regard.

 

[David Hiley]

Quite right on the bell housing/tractor front. I use a 1976 Leyland tractor with that engine to launch and retrieve my boat. As you say, the engine and gearbox are effectively the chassis and load bearing and as such the gearbox and bell housing all one piece. One thing I would add is that the cylinder liners needed regular replacing in the tractors. New rings and liners was a regular task. They worked hard and did far more hours than a boat engine - 500-1000 a year - but maybe worth a look whilst it is stripped down.
Ron Greet Tractors near Totnes in South Devon is a great source of old and vintage tractor parts, new and S/H, and extremely helpful if you are after engine parts that are Leyland standard bits.
Good luck with it all

Thanks. I had heard about the liners being a potential issue and was advised to use fleetguard inhibitor ( by Cummins I believe) to minimise this.

 

[bristoljim]

Hi Jim. Glad to hear your home and doing ok. Image shown is of back plate with startermotor installed. Drop down on original box was 4" so, as you say, prm would fit the bill nicely. Minor differences could be accomodated by going from solid to flexible mounts. Prm will be approximately 12" shorter, which will require some messing about.Pity to lose original box. Although only 60years old the boat is so well built it will last another 60, after I've finished giving her a refurb, and at some stage she will be a classic and somebody will probably want to put her back to absolute original. Mechanical boxes will by then probably only be in museums.
Flywheel is 16" diameter and doesn't appear to be the heavier one one would expect to find on a tractor. But bearing in mind the standard of engineering carried out anything could have happened in that regard.

Could we have pictures of both sides of engine please not too close
Jim

 

[David Hiley]

Hi Jim. I will do my best. There's a 300 L water tank one side and a layshaft with a myriad of belts and pulleys the other. Will get onto it first thing in the morning.

 

[burgundyben]

Here's a pic of the 4/98 with the Lancing Bell housing. Its not a great pic, best I could find.

 

[David Hiley]

Your motor appears to be the same. Startermotor is in the same position. The only difference I can see is that the fuel filters are at the back,above the startermotor on mine, which is not uncommon.

 

[burgundyben]

Your blue engine looks different to my red 4/98.

Yours has a distinctive inlet manifold that I dont recognise.

 

[David Hiley]

Do you have any idea what year your motor may have been?

 

[David Hiley]

Possibly your motor was an automotive version whereas mine is definitely an industrial version, probably a tractor. Could this make a difference?