Winterising that Inboard

[Bigplumbs]

I seem to be asking a lot of questions but now I have 'The Cure' I find myself not knowing much as up until now all I have known about is 2 stroke outboards.

I am sure in time I will get a handle on the inboard. So to my current 2 questions:

1) Has anyone got a manual for the Mercruiser 3 ltr

2) How do you winterise it and the leg. I have found some info on line and I know about adding fuel stabiliser and fogging the engine. I am not sure how to get the water out of the engine and adding the anti freeze. I don't seem to have the little thing I see in videos to easily drain the engine

Here is my engine Remember the block etc was new in 2014

[mlines]

I have the electronic version of the manual as it is widely available on the internet, let me know if you cannot find a copy

Sent from my Nexus 5 using Tapatalk

[annageek]

There should be a thumb screw on the port hand side of the engine to drain the block... its aboutlevel with the bottom of the alternator but further back.

Theres also a brass plug on the underside of the exhaust manifold for draining this too.

The things you talk about from the video are probqbly the quick drain system fitted by mercury on later engines.

Last year I removed the hose from the thermostat housing and poured the antifreeze down there but I dont think that will have put AF in the head (or whatever the thermostat allows water into when it opens). It was at home though and I put a couple of 30W greenhouse heaters into the engine bay just in case. This year we'll be keeping her at the boat yard so will need to ensure it's done properly. My thinking is to run the engine fully up to temp on muffs and have a big bucket of antifreeze connected by hose through a changeover valve. Then with the engine warm (and thermostat open) throw the valve so the bucket of AF is supplying the muffs rather than the hose. Wait till pink stuff comes out of the exhaust and then kill the engine.

I think the leg self drains, so other than tilting it fully up then leaving it fully back down so the bellows can relax, and ther usual oil change, I'm not sure you need to 'winterise' it.

[SpiD]

Easiest way to run the engine on muffs (water supply) until the thermostat opens, then feed a 1:1 coolant/water mixture to muffs until the exhausted coolant (from prop hub) clearly contains the coolant mix. Then shut the engine off.

Will be protected though winter and be ready for next season

[Ianfs]

then feed a 1:1 coolant/water mixture to muffs until the exhausted coolant (from prop hub) clearly contains the coolant mix.

Actually that's one of the most simplistically simple (hmm, that's a tautology but you know what I mean) idea's I have heard for a long time.

My version however might be the most boring.

Drain down the manifolds and engine block. Then fill all the coolant lines heading down from the coolant distributor pump until full with a -20c coolant.

This'll fill the block with enough coolant to -20c. Alternatively follow the above!

[betty boop]

got a paper manual for alpha 1 G2 and 3.0l leg and electronic PDF but may be the new version, iboat.com has the full set for older manuals Ive posted the link before in the tech section

[Bigplumbs]

As far as anti freeze is concerned I was going to use this

http://www.screwfix.com/p/no-nonsense-a ... wwod9vsGpQ

Mixed 50/50 with water. Is that ok

Also I assume once the antifreeze is in the block you just leave it there or do you drain some off

Regards

Dennis

[betty boop]

as good as any that I have used but neat not mixed- on my 3.0l ib I have the newer drain hoses, so run the engine warm - fog the carb to a stop, unclip hoses n drain the block/manifold -with a small funnel pour the antifreeze down the pipes, doesn't need much as about a 1 or 2 may be. Don't forget to lower the leg to stop freezing water in the upturned propellor bell housing bit.

Going to do Betty at the weekend, feel free to drive over if you want to practise and do mine first

[Ianfs]

Mixed 50/50 with water. Is that ok

Hi Dennis

As far as I know the Blue antifreeze should be fine. I’m sure you and others know more than I about this, but there are two types of antifreeze out there for car engines (closed cooling), one is Blue for engines before 1998 (IAT Inorganic Additive Technology) and the other is Pink, for engines after 1998 (OAT Organic Acid Technology). Ethylene Glycol the main ingredient doesn’t go anywhere but the additives do, additives are the anticorrosive stuff. Blue is supposed to last 3yrs and Pink 5 yrs, but you are not supposed to use the OAT Pink stuff in earlier engines and visa versa, something to do with seals and metals used, but not sure.
Raw water cooled boat engines and the life expectancy of antifreeze is down to when we empty it out, i.e.3- 6 months, plus Mercruiser engines have not changed as much as car engines so a 1998 engine would have earlier technology. I have used Blue antifreeze for a long time and have not seen any ill effects in raw water cooled engines. In fact I would expect pumping sea water through the block would have a more corrosive effect.
The most important thing to remember is where you live and has the Winter temperature ever reached a seriously low level i.e. -30, I strongly doubt it. So if you live in an area with moderate Winters as I do, in Sussex, then -20 is well enough for peace of mind, especially when you see the temp dropping to -10 etc. as we did one year, but most of the time its only about -2 to -3c.

As Anna said, always store you boat with the leg down, less strain on the bellows. Also as Ian has said, if you pour the mixture down the intake tube, the long one leading up from the Transom Shield inside the boat, it will drain down into the leg and you'll see it coming out when there is enough in there.

As regards how far you go with Winterisation, that all depends upon how much you know about the Bellows, Impeller and Gimbal Bearing .

As a bare minimum, change the oil in the leg, engine, change the plugs, fog the engine and add anti freeze. I found this last night, if it's any good to you?

3.0 cooling system.jpg (268.48 KiB) Viewed 11705 times

[Bigplumbs]

Ian

Many thanks, That info and diagram is very useful

Dennis