My 15ft Ally and 1250 SuperBP

OK, New thread time.

As some of you know, I bought a 15ft Allison with a 1250 SuperBP last year.
Do to personal issues I was not able to run it last year.

So, last night, after fuel/oiling it throught the spark plug holes and through the Carbs, I fired it up. Initial inspections noted the following small issues.
big fuel leak on one of the crimped Merc fuel lines and no discharge from the water outlet. I want to correct these 2 issues before running it anymore, obviously.

1. Where do I get an impeller for a superspeedmaster? This is the first Speedmaster I have played with. Yes, I know this is not a BP gearcase, it was replaced.

2. I know I can replace the fuel lines with hose barb fittings and hose clamps, but I was kinda hoping I could duplicate what Mercury used.

3. Also, what compression readings should I be seeing once I get it warmed up? Will this thing will run on 92 and Pens synthetic @32:1.

4. For fun, How fast do you guys think it will run? 70ish?

Thanks for the help, kinda dead in here lately...everyone must be last minute thrashing to get stuff on the water.

If you have a customer motor, Merc claimed these were about 140 hp. If you find the compression is higher than what Olegator suggests, you might need better than 92.

For 70-ish you need about a prop with about 13½ - 14 inches of pitch. Don't lug that motor.:eek:

Steal fuel lines off of another inline 6 :rolleyes: That's what I do:D

Quote:

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Originally Posted by LakeRacer99

4. For fun, How fast do you guys think it will run? 70ish?

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That's a good question.... you're probably about right on. Ol' gator will probably know more.

T2x

Seems to me that boat should easily exceed 70. I have seen Olegator run faster than that with a stock lower unit J Production boat.

I too would be curious as to what OLEGATOR says, also Raceman

a stock lower with a 28 @6200 puts you at 70ish and I am thinking the SS is
good for another 5mph

but I think there are those that post on here that should be able to tell you
exactly what it will do ;)

would love to watch you fly it !!!!!

..Dale

Quote:

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Originally Posted by LakeRacer99

OK, New thread time.




2. I know I can replace the fuel lines with hose barb fittings and hose clamps, but I was kinda hoping I could duplicate what Mercury used.

3. Also, what compression readings should I be seeing once I get it warmed up? Will this thing will run on 92 and Pens synthetic @32:1.

4. For fun, How fast do you guys think it will run? 70ish?

Thanks for the help, kinda dead in here lately...everyone must be last minute thrashing to get stuff on the water.

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I'm glad some one started something new here........

For fuel lines give Doug a call, I am sure he will make you ANYTHING you want. Check with Grubbs too.
http://www.vintageoutboard.com/FuelS...Systems_1.html

It will run fine on 92 and Penz 100% @ 32:1

I think it should run well in to the 70's :D

I think finding a blade will be your biggest challenge. I stuck a shiftable gearcase on the T2 on my 15 Ally because of lack of blade availability. Assuming it's 1:1 you're in the 30 pitch range with a 15 comparatively speaking, PLUS the little blades are hooked up so much better that they're really hard to get on top. As far as Jim (OleGator) runnin' faster with the 1500 and big gearcase, that's true, BUT........... a 1500 has more power than a 1250 Super BP. I ran a SuperSpeedmaster on my 15 Ally with a 1500XS, mostly because of handling. I don't think you'll see anything like a 5 MPH advantage over a big gearcase if it's set up right, but no question the SSM's are cool and fun to run. As of about 5 years ago I ordered some of the pre made hoses from Merc and they actually were still available. I can get the part numbers off the boxes in a day or two and you can get em checked.

Thanks for the advice so far guys. I think I have about 10 blades for the SSM, 5-6 2blades and 4-5 3 blades. If that don't work I have 3 XS gearcases that are ready to run and I have a bunch of V6 props.

I am gonna track down some crimped fuel lines and an impella...When I do make it to the ramp, I will have my GPS and my digital camera.

Thanks guys,

If you are going through the carbs, I would go up one jet size on the center. It may be territorial, but #3 was susceptible to go lean on today's gas.

Carb to carb fuel line was part #32-31584a1. Fuel line from pump to carb was part #32-54739a1 and the line from pump to pump was # 32-52943a1. not sure if they are still good #'s or have been superceeded.

Lets see some more pics of the boat!! :)

Find out what your lower unit ratio is before picking a prop.

That's good advice since the exhaust snout is cut pretty short and the SSM might be a lot newer than the rest of the rig. One tooth off isn't going to be much different from 1:1 .... reduction gears from a 700x would be sweet and a lot less likely to bog the motor with the most common props.

Quote:

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Originally Posted by Mark75H

.... reduction gears from a 700x would be sweet and a lot less likely to bog the motor with the most common props.

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Reduction gears....tell us about this. Thanks.... :eek:

What Sam is referring to is the 13:16 gear ratio available on the 650X and 700X 3 cyl Mod 50 engines ONLY. All of the other SSM's of that style were either 14:15 or 1:1. As Sam already pointed out, that housing appears to be the latest style and they were almost always 14:15, although I do have a 1:1 in the late housing also. Decent blades of less pitch than 15" are VERY hard to find.