Removing MD1 flywheel NUT

[ghostlymoron]

Decided to re-start this post as previous one was heading up a blind alley.
Question was, how do you get the nut off the flywheel on a Volvo Penta MD1 engine. I am confident that, with the nut off, I'll be able to shift the flywheel itself in preparation for engine replacement. I need some way of holding the wheel still whilst exerting pressure on the nut.

 

[Tam Lin]

Same question. If you are going to replace the engine why take the flywheel off? I didn't on my MD2B.

 

[prv]

Same question. If you are going to replace the engine why take the flywheel off? I didn't on my MD2B.

Makes it a lot easier to lift the damn thing

Pete

 

[scottie]

As I recall with a very large bar on a 3/4 or 1" drive socket and a certain degree of anger directed through a lump hammer

 

[Len Ingalls]

I have never done this,but,here is a link to online manual.It appears that,after the nut is removed,you will need a puller also.The puller appears to be a round disk,with 4 holes for bolting it to the flywheel.Therefore,you may be able to screw the 2 bolts into the flywheel,put a bar thru them,& use them to hold flywheel.
My preferred method is to use an electric impact gun,as used for removing lug nuts from wheels from a car.Very useful tool.
http://boatinfo.no/lib/volvo/manuals/md1-d1-md2-d2.html#/18

Cheers / Len

 

[Tam Lin]

Makes it a lot easier to lift the damn thing

Pete

Absolutely. How are you going to lift it? If you could get it out on one piece it would save a lot of bother. You probably know this but don't just take it to the scrappy, people want these engines and will pay money for them.

 

[prv]

Absolutely. How are you going to lift it?

I'm not, it's not my engine. But when I lifted out the 2GM20 in our last boat, I first removed the alternator, starter, and a few other easily-accessible bits and bobs, to reduce the weight. The flywheel on that engine is enclosed (and not all that heavy) so I left it be, but assuming the OP's engine is one of those agricultural old Volvos with a dirty great traction-engine wheel on the front, removing it to reduce the weight seems a reasonable idea.

Pete

 

[Tam Lin]

Right, I got a bit confused so will just shut up now!

 

[ghostlymoron]

As I recall with a very large bar on a 3/4 or 1" drive socket and a certain degree of anger directed through a lump hammer

How did you stop the flywheel rotating or did you just 'Shock' it?

 

[parbuckle]

There may be a correct way of locking the crankshaft but I dont know this engine and without any suggestions forthcoming you could consider removing an injector and bring the piston low in the cylinder then feed in some appropriate diameter rope a few ins/cms should do and carefully turn the flywheel untill the rope is compressed this will hold the shaft but I would be loathe to use a hammer better to use a long bar .

 

[oldharry]

++1 for an impact gun. Simplifies an otherwise awkward job. Tying it back with rope will be too springy to start the nut. An iron bar, tyre lever or similar wedged through the spokes of the flywheel against the engine casing will usually hold it firmly enough, even if a hammer is needed. An impact gun will start the nut on a 90hp Iveco 4cyl engine (400Nms!), the Volvo is not as tight as this.

 

[Niander]

That fly wheel is very heavy!
I broke one of those engines sold loads of bits...very sort after to keep the remaining ones going
I chucked the flywheel in a skip...nobody wanted that bit and too heavy to post
think there are some holes in the flywheel so put bolts through and big washers and through a bar of steel drilled to suit and pushed up against something solid like engine bearers or the engine itself ....ideas

 

[parbuckle]

rope will be too springy to start the nut. An iron bar, tyre lever or similar wedged

I would not put an iron bar inside the engine

 

[Ardenfour]

Service manual torque for the nut is 500lbf.

Length of scaffolding tube or big prybar through the front spokes and jammed against the block as you turn the socket, which is 57mm I think. I'd still give it a few thumps with a sledgehammer, they respond well to that, just to crack the joint between nut and crank. Heating the nut wouldn't do any harm either.

 

[ghostlymoron]

Very useful tips thank you.

 

[jakeroyd]

As far as I know these engines don't have a ring gear which you can jam cos the dynastart uses the drive belts on the flywheel to start the engine.
Maybe this leaves trying to block crank rotation using the starting handle and jam this against something.
The rotation might be working the wrong way for you in that the nut loosening direction counterclock wise i assume will just cam the starting handle out of the dog drive ?

 

[oldharry]

rope will be too springy to start the nut. An iron bar, tyre lever or similar wedged

I would not put an iron bar inside the engine

Neither would I.

 

[ghostlymoron]

i think the suggestion was to put an iron bar through the fly wheel spokes and jam it against the side of the engine not inside the engine

 

[cagey]

When I did this 25 odd years ago couldn't get flywheel off shaft (tapered and keyed seem to remember) , only help was 30 mins motor away, couldn't be arsed to tighten nut fully or pein lock tab. Imagine my surprise when I arrived at Mylor to find nut and tab washer in bilge and flywheel wobbling on shaft. Still wonder what sort of damage would have happened had it come off. Didn't hear anything until I got close cos all covers were off and the single pot Volvos were noisy and lumpy.
Best of luck
Keith

 

[cagey]

Stupid me didnt read question properly, assuming right size socket ,scafold pole etc , to lock the wheel i used the largest dia rope i could find that would compress into dynastart belt grooves on flywheel, nice long wrecking bar and smaller wrecking bar youll have to experiment as theres not a lot of room. Tiie rope around wheel loosely tighten up usin spanish wiindlass using bars as far apart is possible when nearly tight move long bar nearly out and rest it on nearest strong surface, for me it was locker with 4x2 placed on top then really tighten up thother spanish windlass (other shorter bar ).
Be carefull tere is an enormous amount of stored energy.
Bol
Keith