A question for those that take engines out.

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Mike k

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I was considering how it would be best to remove an engine the 'easiest' way in terms of minimal or no aligning with prop etc.

looking at my pic, this is a shot of the port side stern engine mounting, the starboard is the same but the front two are slightly different but have in common that the 2 lag bolts hold down all the rest.
100_3650.jpg

My question is can the engine be taken out by simply removing the two lag bolts on each leg that secure the base bracket to the GRP . If so then when re installing its a matter of repositioning excactly over holes in the grp and replacing the lag bolts.

I read a lot about alignments and I can see all the alignments are done above the base backet holding it to the floor so looking to avoid that if possible. Would welcome any comments however harsh on this suggestion!!
 
If they are lag bolts (better known as coach screws I think) and even if they are not I think I'd prefer to leave the bolts/screws into the GRP untouched. I'd prefer to split the rubber mount by undoing the 2 nuts with the lock tabs

I hope they are not lag bolts. I hope they are plain bolts/set screws going into tapped holes in block of aluminium laminated into the GRP. If they are lag bolts and if you do remove them, be sure to use plenty of polyurethane adhesive when you reinstall the mounts

I don't know why you're worrying about adjusting the alignment when you put the engine back in. It's dead easy, with feeler gauges or whatever suits
 
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Having done this many times I would tackle it by removing the bolts securing the engine feet to the structure , these should be tapped into a steel plate laminated into structure so with care there will be no weakening of fixing. Even doing this however for sure you need to re- align when refitting engines.
 
jfm said:
If they are lag bolts (better known as coach screws I think) and even if they are not I think I'd prefer to leave the bolts/screws into the GRP untouched. I'd prefer to split the rubber mount by undoing the 2 nuts with the lock tabs

I hope they are not lag bolts. I hope they are plain bolts/set screws going into tapped holes in block of aluminium laminated into the GRP. If they are lag bolts and if you do remove them, be sure to use plenty of polyurethane adhesive when you reinstall the mounts

I don't know why you're worrying about adjusting the alignment when you put the engine back in. It's dead easy, with feeler gauges or whatever suits
Click to expand...

Could use the opportunity to replace the rubbers too?
 
You will need to check the alignment which ever way you remove the engine as the slightest change in position will result in a measurable difference at the flange. So I would remove the bolts into the structure and it will be easier to lift the motor and replace it, then do a rough alignment check when you refit it followed by a final check on the water, then you will know its 100%.
 
thanks to all respondents I greatly appreciate the advice.

With the alignment I haven't got a clue how to do this, can anyone explain or point me to a link for a idiots guide/ explanation of what to do please?
 
Mike k said:
thanks to all respondents I greatly appreciate the advice.

With the alignment I haven't got a clue how to do this, can anyone explain or point me to a link for a idiots guide/ explanation of what to do please?
Click to expand...

The easiest way to get your head round it is to draw it on some paper.
You have one fixed pint, the cutless bearing, forward of that, it all moves.
Your objective is to have the shaft centred in the stern tube and the engine exactly facing that...
So, slap the engine in and slide the shaft so the bolts are in the holes and the flanges nearly touch.
Now adjust the engine so the flange plates are parallel (use feeler gauges top, bottom, port and starboard), be careful the prop does not hit the tube.
Now, measure how far off tube centre the prop shaft is at the front of the tube, with paper and maths calculate how far front and back mountings need to move to centre it eg....
prop shaft is 5mm low at the front of the tube.
distance from cutless bearing to front of tube = 300mm
distance from cutless bearing to rear mounts = 500mm
distance from cutless bearing to front mounts = 1000mm

rear mounts need to go up 5mm*500/300 = 8.3mm
front mounts need to go up 5mm*1000/300 = 16.6mm

this effectively swings the whole engine and shaft up about the cutless bearing, maintaining alignment at the flanges.
 
Thank you for the excellent responses, I will have a good look at the R and D site ( oddly enough I have just fitted their rope cutter whilst she was on the hard but I digress) , Dougal many thanks for taking the time to explain but just need a bit more if you dont mind.........below are pics of what I have inboard - I am not sure where I could take those measurements as I am in the wet??
100_3644.jpg

20160621_192901.jpg
 
Mike k said:
Thank you for the excellent responses, I will have a good look at the R and D site ( oddly enough I have just fitted their rope cutter whilst she was on the hard but I digress) , Dougal many thanks for taking the time to explain but just need a bit more if you dont mind.........below are pics of what I have inboard - I am not sure where I could take those measurements as I am in the wet??
Click to expand...

Your best guess fro the distances to the cutless bearing will do ok, but you might need more tweaks to get it just centre.
Since you cant (without sinking) get to the front of the stern tube then you can only assume it is already good and make a proxy for it. To do this all you need is to fix something near a visible part of the prop shaft that you can use to locate it. A fancy version would be a metal bar temporarily fitted across the engine well with a ruler fixed to the top, use a set square to measure port/starboard location and make a block that fits between bar and shaft for vertical alignment. Its not really good to wedge the shaft in place since the wedge will fudge the weight taken by the engine.
 
Dougal Tolan said:
Your best guess fro the distances to the cutless bearing will do ok, but you might need more tweaks to get it just centre.
Since you cant (without sinking) get to the front of the stern tube then you can only assume it is already good and make a proxy for it. To do this all you need is to fix something near a visible part of the prop shaft that you can use to locate it. A fancy version would be a metal bar temporarily fitted across the engine well with a ruler fixed to the top, use a set square to measure port/starboard location and make a block that fits between bar and shaft for vertical alignment. Its not really good to wedge the shaft in place since the wedge will fudge the weight taken by the engine.
Click to expand...

thanks very much Dougal
 
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