75HP Mariner (Belgian) Restrictor Plate

NICKK · #1 January 6th, 2003, 08:57 AM

Very usefull board, you guys have already saved me serious time and effort, thanks.

I have a 1991(ish) Belgian made Mariner 75HP Two Stroke. In my parts manual I see that there are two exhaust set ups listed, the USA one and the Belgian one. Now, the Belgian Exhaust has a 'restrictor plate' in it which the USA does not.

So, my question is, if I remove the plate, will I get more power or a big bang?

Thing is my boat is slightly underpowered, I know that the 75 can be converted to a 90 by changing carbs and exhaust, so I thought this might at least help a little. Anyone know anything about this?

All advice greatly appreciated.

Apologies If I have posted this in the wrong place, I'm new to this game 8-)

rwise · #2 January 7th, 2003, 02:58 AM

Nick

I don't think that removing a restriction would hurt the engine, though you may need to retune it for best proformance. If that is the only diference you can find, then I would remove it!

Richard

NICKK · #3 January 7th, 2003, 07:48 AM

Thanks richard,

If I might ask (gulp) what degree of re-tuning is likely to be involved? Are we talking rejetting carbs or mixture changes? I'm a bit weak in this area. Any ideas?

Cheers

Nick

rwise · #4 January 7th, 2003, 03:42 PM

Nick

most likely just retune the carb/s, I would think the jets would not need to be changed.

Richard

NICKK · #5 January 9th, 2003, 08:12 AM

Thanks Richard,

I'll chat to the guys at my local Mariner dealer.

Do you by any chance have any knowledge of the 75 to 90 hp conversion that is supposed to be possible by swapping carbs and exhaust? Any idea who in the US would have those parts cheap (maybe used).

Thanks for your help. next time your in Africa, drop in for a beer.

Cheers

Nick

stemar · #6 January 10th, 2003, 07:17 AM

Hi Nick

I have the same engine 1989 75HP Mariner Belgium made.

I have converted it to 90HP. I only changed the carbs but I did not make any changes on the exhaust. I will say that there were not so major diffrence. The speed increased 5-7 miles and also the fuel to 20%.

Thanks

Hooty · #7 January 10th, 2003, 01:55 PM

Stemar,

Just curious but what was the difference in the 70hp carburetor and the 90hp carb?

Thx. & c/6

Hooty

stemar · #8 January 11th, 2003, 01:55 AM

Hooty,

The 75 and 90 Mariner engines are identical the same. The carbs also are the same size and fits excactly in both engines. The only difference in carbs is the fuel diode, is bigger in 90 carb.

Hooty · #9 January 11th, 2003, 02:42 PM

That's cheap 15hp. and worth knowing about.

Thanks Stemer!

c/6

Hooty

toyvette81 · #10 August 2nd, 2009, 01:20 PM

if its just the carbs.. im doing it