Mariner 4 unleaded?

[Jaz]

I've acquired a Mariner 4 of unknown vintage, serial no. 9713028 and don't know if I will have to use leaded fuel. I'm familiar with inboard engines, but have very little knowledge of outboards. Managed to download a manual from Brunswick Co. U.S.A. but fuel type not mentioned. Mercury website hasn't got much info on Mariner, although they own the brand. Anyone help?

 

[Lakesailor]

If it's 2 stroke I can't think it matters.

(evidence is beginning to show that it's not that the important on old vehicle petrol 4 stroke engines to use leaded fuel. Some specialist reconditioners are saying they are not having problems with unleaded fuel)

 

[Leighb]

I used to have a Mariner 4 some 15 plus years ago, the manual said to use unleaded, but I switched to leaded on the advice of a local dealer simply because it was difficult to start after being unused for a few weeks, which he attributed to the alcohol in the fuel being hygroscopic.
Water was absorbed into the fuel, but when that evaporated it left water behind in the bottom of the float chamber.

Sounded possible and I switched to leaded, had no starting problems afterwards. /forums/images/graemlins/grin.gif

 

[Jaz]

Sounds quite plausible, as mine was difficult to start first time this season until the new fuel (unleaded) cleared through to the carb. Thanks, I'll try leaded .

 

[VicS]

According to This website that's a 1993 model

However from the Brunswick marine website I concluded that it was a 1992 model Belgian made and a 2 stroke

So its '92 or '93 and a two stroke.

2 stokes need neither a high octane fuel, because their compression ratios are low, nor lead additives as valve lubricants, because they don't have any valves.

So it can be run on ordinary bog standard premium unleaded.

However being a 2 stroke it must be run on a petrol/oil mix. I will say without hesitation that you should use a 50:1 mix using an outboard engine oil to TC-W3 specification (The current spec).

The gearbox oil will almost certainly be an EP 90 oil which you should change. (Note you fill them from the bottom using the special squeezy bottle until oil flows out of the top (level) hole. Fitting new level and drain plug washers.

It would be wise to change the water pump impeller and, if there is any sign of water in the gear box oil, the seals on the prop shaft and possibly the drive shaft.

THE PLACE to go for advice on outboard engines is iBoats where you will find a forum dedicated to Mercury and Mariner outboards

The fifth item on the manual downloads list on the Bruswick Download site should be the manual you require, I think . HERE Its a big file though.

I hope this helps

 

[Jaz]

Of course, I was a bit dumb not to realise unleaded is not an issue as there are no valves, but I needed a quick solution, so thanks for your very comprehensive reply.