Project Mercury 350

For pre 1975 outboards and race motors only.

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Rapier
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Project Mercury 350

Post by Rapier »

One of my xmas presents is another of these - pics tomorrow as has been in the rain for a week. Is 30cu in, 35hp pre 1966 facelift - they produced these in '63, '64 and '65. Redesigned model, post '65 were 32.5cu in. and a different block. Up at dawn to start work on it tomorrow. :roll:
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gfgarland
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Re: Project Mercury 350

Post by gfgarland »

Oh, that is nice, a '63!! I have two of them, a manual with a factory tiller and an electric start version. Both are '63 shorties and are wonderful engines, very tough and smooth for a big twin. The 350 was developed as a test mule for the larger engines to test ideas and designs and it was so successful they put it into production. Please post pictures as you go along with the rebuild.

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Re: Project Mercury 350

Post by Rapier »

Thanks for posting over here - some of us post on John's and Fiberglassics. Iam hoping to post pics of the xmas present soon - too many projects on the go at the moment. Took the other gearbox to the workshop yesterday, but ran out of time to open it up - is siezed solid and has chunks missing from the plate, as you can see. Had to cut the impeller off the shaft too...
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gfgarland
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Re: Project Mercury 350

Post by gfgarland »

Worst comes to worst I have a good clean freshwater lower unit here for you. Wonder what shipping would cost to you from here?

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Re: Project Mercury 350

Post by Alacrity »

We can sort it George & Rapier if needs must.
Mercs are like women, no 2 are exactly alike. That's what testing is about. In general it is safer to test motors and props than women!

gfgarland
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Re: Project Mercury 350

Post by gfgarland »

OK. I will pull it apart and rebuild it just in case. I was going to do that anyway but I will move it up the project list. Cheers.

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Rapier
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Re: Project Mercury 350

Post by Rapier »

Back to the workshop today. This time to see how viable the other freshwater 350 was - had compression around the 125 mark on both pots. Cleaned the carb of rank fuel, all fuel lines and fitted a new fuel pump diaphram and check valve gaskets. - it then fired up 2nd pull. The water pump housing has been cooked at some stage and the impeller was jammed in with half a bearing as a key. The baboon spanner team had got there before me....parts now on order. I've taken all the e-start bits off the ex-Healey75 bitsa in the background and will use them on this one - happy days.
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Re: Project Mercury 350

Post by Rapier »

Did the other one today...more fuel residue everywhere. Hopefully this will fire up as easily as yesterday's.
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Re: Project Mercury 350

Post by Rapier »

The '65 350 came home from the shop a few days ago. It's always had a broken lower pan and mangled stainless trim, but I'm hoping to find a replacement in the US. These are pretty 30 cu in models only produced from '63 to '65> Almost delicate looking for an outboard, they're ideal for small runabouts, with the modern full gear shift gearbox, but external remote cables- in short a good Pearly Miss motor and for the 12 ft-ish Selco, Broom Gemini and Microplus runabouts as an alternative to the ubiquitous 1960 to 1971 OMC 40s. Here's one running on an ali boat:-

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Re: Project Mercury 350

Post by Rapier »

A recent boat aquistion has forced me to get on with converting this motor to electric start. Not many of these about in the UK with factory electric start, as was the case then electric start models were priced at a premium, as a luxury, so most buyers saved money and put up with manual versions. The flywheel and starter motor for this motor was scavenged from a club member's bitsa. It has it has the solenoid mounted on the side of the starter - as in the pic, but it is shorter than the version below, without the ali casting at it's base (the one shown is for a pre 1970 Merc 500). Later models had the solenoid mounted on panel in front of the carbs. It can be mounted elsewhere on the tray, but there's a lack of space in most of these twins, so this is a good place place for it to be. Finding starter motors for the twins is not easy here; like those for the 500s there seem to be a plethora of different styles, but this one is a short version without the later lower mounting bracket & rubbers. It is easier to mount than later models, but every fitting on the tray, in that area, has to be removed.
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