Servicing my engine

Sailing newbie selsey

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A bit of advice please, I have an old Volvo penta MD7A engine built in 1979, in my new to me boat, I purchased her this year and had a full service completed on the engine, all filters changed, oil changed, impeller changed this was all done in July before putting her in the water in August. I have only ran the engine for around 6 hours this season as just been doing shorts hops around the Solent. She is due to be lifted out of the water to go on the yard over winter in a few weeks. I will of course flush the engine once ashore and run antifreeze through her, but I plan on not changing the impeller, I will do the fuel filters I think, but do you feel the oil and oil filter will need changing given the low use this year? Thanks
 
I am in a similar situation, having done only a few hours this year. After discussion with the engineer, we decided to leave the oil. I think, no engineer myself, that if the oil still looks clean you may as well leave it. The oil filter is not critical but it might be sensible to change the fuel ones. You should remove the impeller over winter.
 
I never touch the impeller. And change oil and Oil filters at the beginning of the season, (since I went to screw on type as used in iveco vans they have been in place for two years..)

If you have not done it I recommend emptying the fuel tank and cleaning that out...then only using clean fresh fuel from trusted sources with a drop of tratmemt/stabiliser/anti diesel bug stuff...
 
I'm not an engineer but the advice given to me many years ago was to change the oil and the oil filter before it comes out the water for the season. The reason given was that the oil will sit and acidify over the winter which isn't great for your engine. The cost is very minimal against the cost of getting an engineer out if there is problem. Wouldn't worry about the fuel filters till you are back in the water - they may not even need changed but a quick check doesn't go wrong. The impeller is best inspected at the start of the next season - best if just before you go in the water. Again there maybe nothing wrong with it but better to check than end up with a piece of it breaking off and going into the engine.
 
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Problem with the impeller on the OPs MD7A is that changing the impeller may disturb the pump shaft seals!
Point noted as I had the exhaust manifold changed this year and had a nightmare getting the seals again on the pipe work from pump to thermostat! I don’t think I will disturb the impeller this winter given it was changed in July and with so few hours done this season
 
With only 6 hours run and assuming the oil is still clean (which you'd expect it to be) I'd leave that and the impeller. I would have a look at the fuel side - see if there's any water in the bowl of the primary filter, drain if so and if possible same with the diesel tank though this may not be possible or easy. Pandos's suggestion of cleaning out the diesel tank would be a good idea, again though may be relatively straight forward to nigh-on impossible. If the boat was in regular use before you bought her and there have been no hints of anything amiss when you have used the engine I wouldn't consider doing that essential, diesel lasts a long time. I would probably top off the tank, especially if it's a metal one and the boat is ashore...
 
With only 6 hours run and assuming the oil is still clean (which you'd expect it to be) I'd leave that and the impeller. I would have a look at the fuel side - see if there's any water in the bowl of the primary filter, drain if so and if possible same with the diesel tank though this may not be possible or easy. Pandos's suggestion of cleaning out the diesel tank would be a good idea, again though may be relatively straight forward to nigh-on impossible. If the boat was in regular use before you bought her and there have been no hints of anything amiss when you have used the engine I wouldn't consider doing that essential, diesel lasts a long time. I would probably top off the tank, especially if it's a metal one and the boat is ashore...
The oil is still clean and new looking, still that golden out the bottle colour, no water in the primary fuel bowl, the tank is a nightmare to get to no inspection hatch and not even a fuel gauge. I put about 9 lots in her and topped her right up when I bought her and put a strong dose of fuel set in the tank, will top her up once ashore
 
Point noted as I had the exhaust manifold changed this year and had a nightmare getting the seals again on the pipe work from pump to thermostat! I don’t think I will disturb the impeller this winter given it was changed in July and with so few hours done this season
Bit late for you the pipes with square section seals should be loosened at both ends and not bent out of shape to prevent difficulty in sealing
 
Why not change the oil, it is a few quid and will give your engine a lovely clean oil bath over the winter.

I had an impeller fail after 24 months 'in commission' use, the rubber delaminated from the inner bush. Not fun a mile off Dodman Point. Cornwall in a strong tide and a F1!
 
The oil is still clean and new looking, still that golden out the bottle colour

It matters how/when you check the oil.

I had the same impression with my oil at the end of this season. I hadn’t done many hours (a few more than you) and checking the dipstick showed a good oil level and clear golden coloured.

The oil that I use isn’t cheap and I seriously considered leaving it another year. As stated above, I am of the opinion that it’s better to change the oil at the end of the season rather than the beginning so I bit the bullet and changed the oil after running the engine for 20 minutes. Running the engine does make the oil flow better and picks up the contaminants sitting in the sump. The oil that I extracted was black and not the golden colour that I had seen on the dipstick.

I doubt that using it another year would have been catastrophic but I’m glad that I changed it (and I hope that my engine will thank me next year…)
 
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