Engine mounts rust

Sailor2000

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Hiya, just wondering if anyone would have any opinion if I should wire brush it down and potentially repaint with something or replace? I’d like to think it’s surface rust as it still feels quite solid.

Or replacing next season.. probably an awkward job

Thanks
 

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From what I can tell , over the years slight deck leaks from rain water possibly , boat is new to me, so I’m unsure, feels quite solid, so I’m hoping surface rust, bolts look recently greased. After wire brushing is there anything I should add?

Thanks!
 
Abrade with aluminium using sunflower or linseed oil as a binder.

in that application I would probably try the biggest ally roofing nail I could get, in a drill chuck.

I might not bother wite brushing, since I think the rust catalyses the polymerisation reaction, but even if it doesnt it likely acts as an inert filler, and should do no harm.

I actually have some that would probably benefit, though I’ll have to hack the companionway apart to get access. I’ll try and remember to take some pictures
 
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From what I can tell , over the years slight deck leaks from rain water possibly , boat is new to me, so I’m unsure, feels quite solid, so I’m hoping surface rust, bolts look recently greased. After wire brushing is there anything I should add?

Thanks!
The left hand mount on my starboard engine looked very similar to yours. The cause was a raw water leak from the raw water pump. Sherwood pump. Dreadful things. I wire brushed the mount and spray painted it. Looks fine now. The pump was replaced.
 
I read somewhere that they should be replaced every maybe 5-6 years, I’m pretty sure mine certainly don’t look like that… I’m not suffering any crazy vibrations / bouncing around of the engine, so I am hoping I can squeeze another season…
 
They look fairly ancient ie are they from this century?
Engine feet have a defined life after that the rubber loses its resilience sags and the engine drops out of alignment.

Probably time for new feet and to realign the engine to the shaft line. Also think about replacing cutless bearings with realignment as the engine drop and sag will probably have caused uneven wear of cutless bearings.
 
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I read somewhere that they should be replaced every maybe 5-6 years, I’m pretty sure mine certainly don’t look like that… I’m not suffering any crazy vibrations / bouncing around of the engine, so I am hoping I can squeeze another season…
This, if true, is probably because the rubber component is expected (intended?) to fail. Oil contamination will promote this.

The engine mountings on my 1986 car were failing in tension (cracking). Since I had them off anyway, to take off the sump, I tried a half assed forlorn hope repair involving degreasing (IIRC detergent wash then alcohol), putting them under compression by wrapping as many cable ties as possible around them, and then running superglue into the cracks

The bolts were long enough to leave the ties on when I put the mountings back on the car. I expected the ties to fail early in service, but they were still intact when the cops got the car 7 or 8 years later. I doubt the glue did anything.

I suppose noise and vibration may have increased a bit as a result of an increase in mounting stiffness, but if so I cant say I noticed.

People use stiffer polyurethane engine mounts on cars, either bought, or DIY cast from resin. They are also allegedly carved from ice hockey pucks, but I asked the Taiwan expatriate Canadians to check pockets and, sadly, they came up empty.
 
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Assuming rubber has not lost its integrity
Unless you are desperate to make work and spend money (have you checked the price of engine mounts) would wire brush that mount and after masking off the surrounding glassfibre give the metal a good coat of Hammerite or similar.
In a difficult place to get at ?, buy one of those wire brushes a long broom handle normally sold for cleaning between patio paving slabs.
Will enable you get at a mount buried in inaccesssable location
1772274605550.png
Cut handle to suit . Applying the paint might be the difficult job ?
 
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Assuming rubber has not lost its integrity
Unless you are desperate to make work and spend money (have you checked the price of engine mounts) would wire brush that mount and after masking off the surrounding glassfibre give the metal a good coat of Hammerite or similar.
In a difficult place to get at ?, buy one of those wire brushes a long broom handle normally sold for cleaning between patio paving slabs.
Will enable you get at a mount buried in inaccesssable location
View attachment 207089
Cut handle to suit . Applying the paint might be the difficult job ?
Thanks for that, rubber doesn’t seem to be peeling from the sides, no huge vibrations throughout the boat, but probably not an immediate job I hope. Will give a wire brush and coat & think about replacement eventually, I’m guessing I’m not the only one with this problem.
Thanks!
 
That's the trouble with modern engines that don't leak enough oil to protect the paint and chrome work on auxiliary components. Modern motorbikes suffer the same problem, I find. 😁
You could rely on the old Volvo Penta 40 and the earlier of the 41 series, which used a pretty useless crankcase filter to coat everything with a fine coating of oil over everything in the engine compartment, wether wanted or not.
The newer engines had the improved closed system which ducted any fumes back into the engines to be burnt. ?
 
Access seems to be a pain in the butt in my boat for replacement engine mounts, well
The back ones are, I guess nothing is impossible, but hopefully able to get the front 2 replaced eventually.
 
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