65XS merc

[arkansas river rat]

I have a question for all. What do you all think of the 65XS merc 1974? I've found one complete and runs for $600.

[pat]

I would say go for it if it is in running condition. I'm not sure that it is a 1974...more like a 1975 which was the year they were introduced if I'm not mistaken. This is a very fast engine and on par with the OMC 75 Hustler/Stinger. Prop needed would be a Mercury racing 3-bld cleaver 11 x 18 if you are looking to put it on a V-bottom.

[arkansas river rat]

Thinkin on putting it on a 15 or 16 ft semi v jon boat for river racing. From what i have read it wouldn't have a problem running of 106 octane fuel .

[trident]

650xs???

Do you mean 650XS?

Yes, fast and fussy to tune, Idle poorly, rough midrange, but really run, if right, at WOT.

Needs good fuel, good oil, correct jetting and carefully set timing, as they are "thermally sensitive". Look at the piston, you'll see why.

Nastiest carbs I've ever worked on, BTW.

Jerry

[arkansas river rat]

Are there any carbs that i could put on the motor to make it easier to tune?
Rightnow i don't know if it's a true 65xs I do know it the front have is from a 65xs. I know feeding a 3 cylinder with 3 carbs is better than a 2 carb setup. Would the front half work with a 49 cu in 1980

[trident]

Not a 65XS !

There is no such thing as a 65XS. Its a 650, 700, 650XS, 650X or 700X.

The latter three models were 3 carb / 3 cyl, monster Tillotsons, not used on any service motor. Similar to the 6 used on the T2X.

Sheesh.

No other carbs that I know of.

I don't ever recommend mixing / matching cases and blocks.

If you buy it, learn to tune it. I can help...

Or buy something milder, less fussy. These motors, the 650XS version, were fast, but they were a failure in the marketplace and Mercury quickly discontinued them. Wanna guess why?

Jerry

[arkansas river rat]

650xs is what i was talkin about just left out the 0 . If the blocks are about the same should just have to align bore the block after mating the two and change the carbs out for more reliable ones . If there is a will there is a way

[pat]

The 650XS engine was designed specifically for racing and the internal intake, transfer and exhaust chambers and ports are much different than the stock 3 cylinder 650. The carbs and jets were designed (over-sized) to deliver the needed volume of air and fuel mixture to get the 90HP that this engine delivered. This engine was not legal in APBA EP because it was considered a non-stock engine. It was allowed to run in CBF sactions (Canada) because of Mercury's political clout. At $600 you have a bargin for what you are getting but you also need to worry about parts which could be hard to come by.