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Author Topic: Another help required.  (Read 827 times)

KBIO

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Another help required.
« on: August 06, 2020, 04:56:33 pm »

Hello!
I have this engine for years , and I suddenly wonder if it is a MONAHAN 's one??
Any idea?
Thanks for your help.
Regards.

ooyah/2

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Re: Another help required.
« Reply #1 on: August 06, 2020, 08:19:01 pm »

Yves
It's a John Hemming's   "V"twin. Richmond engine, with Boiler feed water water pump.
Not my engine but one that was repaired for a friend.
George.
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KBIO

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Re: Another help required.
« Reply #2 on: August 07, 2020, 07:16:37 am »

Good morning!
Thanks a lot Georges.
John Hemmens Richmond "V" oscillating engine.
Best regards.

Seacommander

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Re: Another help required.
« Reply #3 on: August 22, 2020, 10:01:49 pm »

Agreed, Hemmen,s Richmond,
Wish I'd never seen mine, rev's like hell and leaks steam from between the two plates
Well at least mine does,  empties a Macc 3 1/2 boiler in twelve mins
I need a much bigger 4 blade prop and also understand how to close the two plates to a steam tight joint
Suggestions welcome
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KBIO

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Re: Another help required.
« Reply #4 on: August 23, 2020, 01:47:48 pm »


Hello!
A oscillating engine slightly leaking is natural and allowed. J. Hemmens engine is very well machined and should not leak . The one I have works fine with normal minor condensate leaks :  45 psi with a 2 1/2’'  3 blades propeller in an Orion moulding hull.
Now, if you cannot see the engine running because surounded by the steam, there is a slight problem !


It would be easier if having some figures and a pic of the plant running to have a better idea.


On my side , I can see 3 reasons for the engine leaking:
- Leaks from the 4 way valves distributor   >>>>>>>>> dsimantled and check for dammage of the O’ring = change  and check for scratches
- Leaks from the piston shafts >>>>>>>>> tighten the stuffing box or insert new packing eventually.
- Leaks between the cylinders and the main body (apparently Seacommander issue) >>>>>>>>> Misaligment = stiff point when turning = dismantle
                and align.
   -May be caused by damaged surfaces of the mirrors: scratches. = dismantle and re-surface it with marble or >1000 wet sand paper grain.
        Re-align properly.   (doubtfull if the engine has not been dismantled)
   -It may also simply come  from a generous steam supply and the engine cannot take it all . Steam oulet undersized or partially plugged. Do
       a test with no exaust pipe  and check again for leaks.
Use a good heavy oil for a better sliding. ((see proper post and discussion on this matter) . We can read somewhere  that the steam is enough to lubricate. Comics are everywhere! I would say that everything has a sliding coefficient (even cement) but so far we did not fine anything better than mineral oil to lower frictions at 140 °C  in our installations.


Maybe someone will have another idea for the benefit of all.
Hoping that this will help….
Kind regards.


https://youtu.be/ezKauubx8GM

Seacommander

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Re: Another help required.
« Reply #5 on: August 23, 2020, 06:03:13 pm »


Many thanks for the post back and you most comprehensive points and explanations
All that you cover is OK ,
The leak on mine is between the two aluminium plates that form the back plate to the engine  -
Open this up and there are cut / milled ports to the engine port faces.
The cylinder blocks and all the mechanism works well, it just steams out of the top of the Ali plats , in cold weather it's just to bad
Thanks in anticipation
Mark
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ooyah/2

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Re: Another help required.
« Reply #6 on: August 28, 2020, 01:17:25 pm »

Hi Mark,


As you have already opened up the Ali plates and seen the grooves  e.t.c. why not open it up again and make a gasket using oiled brown paper.
With a scalpel or a very sharp blade cut out the passage ways and all holes that will allow steam to flow, oil the brown paper gaskets and close up.


If you are not confident in this why not go to Halfords and get a tube of cylinder head gasket compound gently steer the touching faces making sure that you don't block any holes or milled passageways , allow to dry and then close up. clean when closed with Meths to clean external seepage at the joints.


George.
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