Engine removal

JamesL1969

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Hi All

Just joined the forum as having sold my Tomahawk 25, I have now become the owner of a Mirror Offshore.
As luck would have it, this was free to me and it would be evident to anybody as to why.
She needs work but nothing that cannot be resolved.
My question is this:
She is a shallow long keel and does not have the best capsize ratio but would suit estuary sailing (I am on the Suffolk Coast so Orwell/Deben Stour are on my doorstep, so not an issue).
The engine is seized and I plan to remove it and place a long shaft outboard to stern.
If I do this, will I affect the stability to a great degree tso as to make her unstable or will she be OK?

Many thanks in anticipation
James
 

VicS

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Mk 2 Mirror Offshores were fitted with an outboard rather than in inboard diesel. The ballast was increased and a taller rig with more sail area fitted.

I should have some figures somewhere.
 

VicS

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Mk 2 Mirror Offshores were fitted with an outboard rather than in inboard diesel. The ballast was increased and a taller rig with more sail area fitted.

I should have some figures somewhere.
ballast increased from 380 lbs to 700 lbs
sail area increased from 122.4 sq ft to 152 sq ft ( max197 sq ft)
 

JamesL1969

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Thank you for your replies,
Mine is a MK1
I am thinking I will leave the engine in situ so as not to affect the stability. I had plans to use the space for a Porta Potti as the original toilet has been removed,
I have to say, it is a job I was not looking forward to so may be a good excuse.
What would you do?:)
 

LittleSister

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Mirror Offshores have done some, er, offshore sailing (e.g. mainland USA to Hawaii; long distance around the Med; and Humber across the North Sea to the Netherlands and back; at least) so aren't that incapable or limited to calm, inshore waters. From comments from people who have done such trips, putting up with the rolling was the challenge, and none that I've seen mentioned being worried that they were in particular danger of capsizing. (There's school of thought that a shallow keel is an advantage in coping with big waves - the boat tends to slide sideways rather than trip over its keel and capsize.) You will have to decide for yourself what conditions you feel comfortable with when you have experienced the boat.

To my mind, an inboard engine is a real boon if you are cruising, rather than just doing local day/weekend local sailing, so one of the appeals to me when I was thinking of buying one was the inboard engine, and if I had one with a dead engine I'd want to replace it but understand that is a huge outlay on boat you got for free.

If you are replacing the engine with an outboard, I'd remove the engine to create space, but replace the weight with some concrete ballast, or steel punchings in polyester resin, in the region of the engine beds (the lower and nearer the centre of the boat the better, especially as you are putting the weight of an outboard exactly where you don't want weight - high up and at the extreme end of the boat).

I wouldn't bother with increasing the ballast above the weight of the engine (or even worry much about getting it up to exactly the weight of the engine/gearbox/stern gear if that causes complications). That will only slow the boat unless you also increase the size of the rig, and I thought that increasing the rig size was a dubious move on the part of the builders of the later Mk2 version, making it neither fish nor fowl, let alone for someone starting with a usable Mk1. They were never designed to be sprightly, and were sold as motor-sailers that wouldn't frighten the family. Accept it for what it is - cheap, basic but adequate facilities (smallest production sailing boat with separate heads compartment, perhaps?), very easily handled, and aimed at pottering and having fun. For the latter you don't need to go fast or be close winded.
 

TLouth7

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When I took the diesel out of my Sigma 33 and put her back in the water the stern was floating around 8 inches higher than normal. I can't say I have noticed a difference in sailing performance/tenderness between her original trim, that bow-down trim, or her new setup with the batteries moved aft to rebalance somewhat.

Consider that we don't expect to see a massive difference in stability between a boat sailed singlehanded, and one with several hundred kilos of crew onboard.
 

B27

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What's the engine?
You could replace it with a couple of batteries, weight might be similar?
 

PetiteFleur

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It might be useful after you remove the motor is to investigate whether it's feasible to repair it. What make is it and how long has it been seized? I would certainly strip it down and check it - if it's not cheaply repaired you may be able to get a second hand identical engine. As mentioned an inboard diesel is a bonus.
 
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