Mercruiser 3.0L

[Geoffs]

I’ve been running my 3 litre Mercruiser for nearly 5 seasons, and it has never missed a beat. But…………it’s recently developed an oil leak from the forward crankshaft seal. It’s done about 450hrs, so has had some use.

I’ve been told this is a fairly common failure on the 3 litre, and been told to expect a bill for about £900. Ouch! Apparently I can expect the thing to be out of service for about 3 weeks (time to get parts etc.), not what I want this time of year.

I’m just wondering how many others have had such an oil leak problem with this engine, and if the figure to fix, I have been told to expect, is in the right area.

My Mercruiser dealer recommendation is to run to the end of the season, monitoring oil use. At the moment I’m adding about 1 litre of oil every 10 hours. Any thoughts on this?

With a potential cost of nearly a grand, my thoughts are turning towards a re-engine with a 1.7Dti, heard great things about it hereabouts. However Barrus and dealers don’t seem too enthusiastic about such a swap.


<hr width=100% size=1>Old Chinese proverb 'Man who sail boat into rice field, soon get into paddy'

 

[BarryH]

900 QUID. Someone some where is taking the piss bigtime! I changed the crank seals on my lump the end of last season. Cost of parts was 5 quid, time taken was about 4 hours.

Ok, so I done it myself. The seals were sourced from Mercury Bearings & Seals, a local place to me at trade prices. Even so, if I'd got them at retail, they would have been no more than 12 quid including the VAT. After 5 seasons the theres no issue about using non "mercruiser" parts. Get the dimensions of the seals which will be on the outer face and go to the nearest hydraulic/ seal suppliers. Theres actually one in Poole. If push comes to shove, give me a shout and I'll give you a hand witht the job.

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[Freebee]

If you do a search of the internet perhaps auto restoration sites I think you can buy an oil additive that will swell oil seals and stop leakage, that might hold you till the end of the season worth a try maybe, but its a bodge. I have found mercruiser dealers a bit reticent about giving quotes for engine swaps I don't know why?

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[aztec]

good man, i'll second that.. barry if you want the workshop, it's here.

geoffs, what you up to this weekend (sat night) fancy a beer on the quay (wareham)?



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[BarryH]

Oooh Mike, no. Don't like the stuff. yep it will stop the leak for a short while, but it will ruin the rest of the stuff long term and cause premature wear. Valve stem oil seals will be the next lot to go. Then the rest of the crank seals. You'll end up stripping the thing down and spending loads more money.

The 3 litre merc is quiet a nice engine to work on. The front crank seal is housed in a front cover. So removal is fairly straight forward.

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[Freebee]

I don't disagree I did not say I was recommending it. Its just an option.

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[Geoffs]

Hi Steve. Like Duncan I was thinking of going round to Swanage for Carnival and fireworks. But the pull of a beer on Wareham Quay is quite strong. Will have to consult my daughter, who will be with me, and let you know.

Thanks for the comments Mike and Barry. Must admit thought 'goody' about Mike's idea to keep it going for the rest of season, but 'ah!' after Barry's comments.

Never been mechanically very adept. Did change an oil pump on a Petter once, but that was in a big engine room, and could get both hands inside the crankcase.

The bloke I spoke to reckons the engine would have to come out, expect that, and would have to drop the sump and all sorts of things to get to the seals, replacing all sorts of gaskets and things on the way.

<hr width=100% size=1>Old Chinese proverb 'Man who sail boat into rice field, soon get into paddy'

 

[BarryH]

That would be the chap based where you keep the boat in the workshops. I know him. Depending on the room around the engine it may be possible to do it without pulling the thing out. Most of them will pull the engine because thats what the book says and the labour charges then go up respectivly. OK they're in business and have to eat and pay the mortgage. Even so, the cost of £900 still seems very steep for what it is. Bearing in mind you'll have praps 2 gaskets, the seal, oil and a new filter for good measure, call it 100 quid in parts and thats being generous. 800 quid labour is still on the steep side. Its easily possible to do that job in a day. So call it 8 hours. 100 quid an hour! Bloody hell, tell you what halve his price and I'll do it for you!!!!

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[Col]

Not familiar with the 3.0ltr. If its similar to V6 / V8 set up, I have changed these without removing sump or timing chain cover by carefully prying out with a long thinnish screwdriver, then carefully tapping new seal in with a suitable sized tube. Can't always get away with it. But worth a try.

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[BarryH]

It is a similar set up. Thats why I thought 900 quid was steep. Even with stripping off the ancilleries pulley's and stuff around the front of the lump I can't work out how they get the 900 quid figure.

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[Col]

Blimey! that is dear. Wotcha reckon £800 if we do it ? half each??

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[BarryH]

Nah, £899.99 seems fair.

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[Col]

Geoff I know Bazza has offered, If, for any reason he can't make it when you want to do it, give me a shout!

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[Geoffs]

Thanks, Col.

I'll try and keep running,at least 'til the end f the summer hols. I carry plenty of oil and have a good drip tray, stop bigles getng too messy.

Depending on how things go, may well take your and/or Barry's offer (with apropriate consideration, of course!). I might even learn something.

<hr width=100% size=1>Old Chinese proverb 'Man who sail boat into rice field, soon get into paddy'

 

[Geoffs]

There is a fair anount of room around the engine, but probably not as much as yours. Front mount is infront of the pulley, so I guess that has to be got out of the way, somehow.

Anyway, l'll run it for now,see how it goes. Can't do any harm, can I? As long as I make sure there's plenty of oil, and it's not coming out faster than I can put it in.

<hr width=100% size=1>Old Chinese proverb 'Man who sail boat into rice field, soon get into paddy'

 

[BarryH]

Shouldn't do any harm. Might get a bit messy though if the pulley picks it up and stars flinging it everywhere. Had a word with a chap I know who is a Mercury spanner chappy up here. He rekons that it is possible to change the seal without pulling the engine and dropping the sump. Also that the three weeks out of commision is in his words "Your having a f******* larf mate, what the F******are they gonna do regrind the crank as well". His words not mine. He would say that the job would be no more than a day at the very most and should be around the £200 pounds mark max. Apparently the dealers will always quote book times. The seals are not made by Mercruiser and according to him your 3 ltr was one of the only purpose designed marine petrol engines from Mercury. The others all automotive lumps.

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[Geoffs]

It's not being picked up by the pulley at the moment, just running down onto the sump and dripping off. I've put a drip tray under to keep things clean. Nothing worse than pumping out oily bilge water!

Your Merc. man seems a colourful character!

Background to the engne is interesting, I did a bit of research. It is, of course, a GM unit, built in a factory in Mexico. It's not made as a marine engine as such, but a general work horse, pumps, generators etc., and of course marine. But not automotive, wouldn't be acceptable as such. GM do a single point fuel injection kit, got to better than a carb., but Mercury don't seem keen to fit it.

The GM web site has all sorts of data, power curves, fuel consumption curves etc. as a matter of interest, GM only rate it at 145hp with EFi, only 140hp with carb. Mercury figures a bit optimistic, perhaps, unless they use a different carb.

<hr width=100% size=1>Old Chinese proverb 'Man who sail boat into rice field, soon get into paddy'

 

[SteveJ]

Geoff. i would keep a close eye on the oil consumption it sounds like its the seal in the timing cover on the front of the engine, because of the front engine mount the engine will almost certainly have to come out of the boat. The quote does sound expensive for a job that should take about a day, as for the boat being out of commision for three weeks that is taking the p***. the oil seal should be a stock item. As far as the 1.7 DL conversion goes it should fit as it is no bigger than the 4.3L which fitys in the boat as well however the hole it goes through isnt so you would have to remove either bits off the engine or cut the boat about, also the cockpit floor will have to come out in order to run the fuel return pipe to the fuel tank, as the floor is put down with sikaflex it will almost certainly have to be replaced.

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[Geoffs]

Thanks for all that,Steve. Hope the new job is going well.

I'd foregotten about the perils of removing the floor, you had mentioned that before!



<hr width=100% size=1>Old Chinese proverb 'Man who sail boat into rice field, soon get into paddy'