Engine Replacement Project

ianat182 said:
Have you checked the rotation of the new gearbox to suit the existing prop.It maybe a lefthand turning shaft or vice versa.
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Yes, both LH


Tam Lin said:
My old engine came out through the companionway hatch in one piece.
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reeac said:
I had a Centaur reengined some years ago. The very experienced engineer who did it lifted the engine a few inches using a chain hoist and a timber across the top of the companion way. He then swung it for'ard into the cabin so that it was directly below the open companion way roof.
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Sounds like I need to look at this option, I did not think there was room to hoist vertically form the salon, but clearly there is. Sounds like it would be a big advantage not to have to remove the fly wheel.

Thanks for all the advice, I hope to take a day off this week to get it diconnected, and then hoisted out at the weekend. I'll let you know how it goes.
 
ghostlymoron said:
To remove the large nut I borrowed a large socket (about 56mm as I recall) and smote the bar through it with a sledge hammer. I checked the four bolt holes with a tap and they seem to be between m8 and m10. As there doesn't seem to be an m9 size, does anyone know what size they are?
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To be honest, trying to get the flywheel off is more bother than its worth. As Vic S has said the nut is torqued to 500 ft lbs. When I was trying to get my flywheel off, I had to open up the inspection hatches and jam pieces of wood round the crankshaft to lock it in position. To give you some idea of what 500 ft lbs torque is, when I was rebuilding the engine, the torque wrench I used was over 4 feet long and I needed the help of two strapping big fitters.
 
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Hi Gary, I have a flywheel removal plate which I made up to remove the flywheel on my old MD5. Taking off the flywheel
made engine removal a lot more manageable. You can borrow the plate or I will sell you it. To get the flywheel off you block
it with a stout lump of wood then give the nut a whack with a cold chisel and lump hammer. Heating up the nut with a
blow lamp will help loosen it. To remove the flywheel the plate goes over the end of the central shaft. Leaving the central
large nut on but screwed out to the end of the shaft might be a good idea. Screw in four bolts through the holes in the plate and tighten them until the flywheel pops off. It does release with a bang and you need some wood underneath to catch it when it drops.
Regards Phil
 
Jcorstorphine said:
To be honest, trying to get the flywheel off is more bother than its worth. As Vic S has said the nut is torqued to 500 ft lbs. When I was trying to get my flywheel off, I had to open up the inspection hatches and jam pieces of wood round the crankshaft to lock it in position. To give you some idea of what 500 ft lbs torque is, when I was rebuilding the engine, the torque wrench I used was over 4 feet long and I needed the help of two strapping big fitters.
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The front wheel hub torque on a Citroen 2CV is a mere 250 ft-lbf, and that needed a 3/4" drive breaker bar with four feet of scaffolding pole on the end and me jumping on top of that to get it shifted. I suspect some corrosion was involved.
 
I got my nut off relatively easily with a two foot bar and a sledge hammer. I'll have to borrow a big torque wrench to torque it up though.
JumbleDuck said:
The front wheel hub torque on a Citroen 2CV is a mere 250 ft-lbf, and that needed a 3/4" drive breaker bar with four feet of scaffolding pole on the end and me jumping on top of that to get it shifted. I suspect some corrosion was involved.
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I have a Bukh which, thankfully, has a flywheel that is relatively easy to take off. Reading through the thread makes me think the last thing I would do is try to take this one off in the confined space of a Centaur's saloon. There's also the issue of applying enough torque to make sure it doesn't go walkabout in the saloon at 3000 rpm.
Looking at the pics I think the gearbox has to come off and then pull it forwards towards the saloon and extract it through the companion way. Having the gearbox off means the unit won't have to come so far forward because the COG will be narer the stern.
I'd also get a man with a crane who knows his arse from his elbow around boats.
 
We took a similar engine out of a nic 32 a while back, it looks about the same gap to get it through into the saloon. We used a plank of wood as a lever to get it over the lip onto the saloon deck then the boom to lift it out and onto a pallet. Two of us and we are not gorillas.
 
Following another current thread regarding siphon-breaks.

My current installation does not have a siphon-break. the water route is - seacock > strainer > gearbox > pump > HE > exhaust

Gemini has not had one for 40 years, but should I be planning to install one as part of the engine replacement project?
 
Yes. Between the water pump and the heat exchanger. On your new engine there is no means to put it between the HE and the injection point. So seacock, up to a strainer above the waterline, down to pump then up to the anti syphon and down to the HE.
 
I can see why boat yards charge so much to replace engines, 2 days work and so far the engine is as far as the cabin.

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Next weekend:

1) Hoist out using the boom (Sounds easy when you say it quickly!)

2) Remove engine bearers, clean and send off for galvanizing

3) Clean engine bay and paint

Thanks for all the advice that helped me get to this stage.
 
If lifting with the boom, make sure the topping lift or main halyard is attached to the boom at the same point as the anchor for the hoist and take guys from the end of the boom to the aft cleats on deck so that you can control it.
 
Tranona said:
If lifting with the boom, make sure the topping lift or main halyard is attached to the boom at the same point as the anchor for the hoist and take guys from the end of the boom to the aft cleats on deck so that you can control it.
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+1 but you may need to have the boom at an upward angle to give sufficient clearance to clear the coach roof unless you haul it out onto the bridge deck.

However I just wonder if you should in fact haul the boom up so that it is at an angle of approx 60 degrees to the horizontal. That would put the end of your boom directly above the center of the hatch on a Centaur. By doing this you will have a greater force being taken by the mast boom gooseneck and less by the halyard (said he trying to remember triangle of forces from over 55 years ago) whatever you do, you should look very carefully at the boom fittings and the condition of the halyards

One other point to keep in mind that if the lift fails for any reason and the engine drops say, 2 meters, the engine with a mass of 250 kgs will be hitting your boat at 5 m/sec.

Anyone remember how to calculate the forces.

Boom to mast head is 28 feet
Boom is 12 feet
with boom at an angle of 60 degrees from horiz, halyard length to boom 19 feet

ISH
 
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New engine arrived today - Whoop whoop!

Just looking at the cooling system. specifically ordering some new intake hose.

All the pipe work (seacock, strainer, anti-siphon) uses 19mm ID pipe, with the exception of the gearbox inlet and outlet tails, these are 16mm ID.

A trial fit with some 19mm pipe, and it is looser than I think would be acceptable.

The gearbox is a MS2B, I have had a look around and cannot find any replacement tails at all, let alone 19mm ones.

What is the best solution to this problem?
 
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When I did my engine
I found a local company that specialised in agricultural hoses, hydraulics etc tapered non tapered, heat resistant pipe
They had everything and all at the right price!
If you know a local agricultural contractor ask him who they use
 
Keith 66 said:
Lifting an MD2 with the boom? make sure nobody is standing under it.
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So far only hoisted in to the cabin.

I was planning to get it fully out this weekend, put postponed until this Saturday when I have more help available.

Can't say I am looking forward to it, but there seems to be a fair number of people that have removed engines using the boom, and I have yet to hear a story of a failed attempt.

Picture of one being removed (similar engine & weight) with a boom seems to confirm it's viable.

http://coxengineering.sharepoint.com/Pages/default.aspx
 
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