What to do now

[Seadogpdd]

i have 1982 sea ray amberjack 25 with 350 Alfa one fresh water cooled wot 4200 to 4800 low hours on motor can only get 3400 rpms with 17 p prop went down to 13 pitch got close to wot but boat will not get out of its own way get lost in swells in ocean should I go to 21p to get power in ocean on not we’re about wot is boat to big for motor help

 

[Scott Danforth]

if you cant spin a 13p prop you have an engine issue. going to 21p would simply kill it.

you need to do the following:
check the compression
check the fuel
check the shutters

 

[alldodge]

Is this a new to you boat?

If it is, agree, start with a compression test, which should be in the 150psi range, warm engine and throttle held at WOT

If compression test good, check
Timing 8 BTDC
Point gap .16 to .19
Dwell 26 - 31 degrees
Plug MR43T gap .035
Idle 650-700 RPM in gear
Fuel pressure 3 to 7 psi from idle thru WOT

And WOT should be 4200-4600 using an accurate tachometer. The boat Tach may not be accurate

 

[Seadogpdd]

Motor checks out fine can spine 13 prop how to find what prop came on boat it had to come with prop I figure taler prop giVe me more bite in river boat good in ocean no power you no how many props can I buy

 

[Scott Danforth]

your motor would have had a 19 or 21 pitch to begin with

however since you only get 3800 RPM with a 17 pitch, and you had to drop down to a 13p to get "close" as you put it - you have a motor problem, and a major one.

the compression is either gone or you lost the flappers and they are choking off the motor or your throttle cable isnt pulling the throttle open or your running on 6 cylinders. however your motor is not fine.

so, what are your compression numbers?
what is your fuel pump pressure?
what did the contents of your fuel filter look like?
got a pic of your shutters?

 

[alldodge]

There is a possibility that the drive ratio was changed. Figure a 25 footer would have a 2.0 when new, it might have been replaced with a 1.47 or so

 

[Seadogpdd]

I have no exhaust flappers at all never put back can that be problem and I do believe I have a 1.47 gear ratio that came on the alpha one outdrive I guess I’ll pop the top and count the teeth to be sure Back starting point thank you

 

[Seadogpdd]

I opened top 22 20 tooth lower flowers reverse 28 28 drive here 17 that’s what I have with current issues now ha another Alfa drive with 22 20 on to but foward reverse 21 21 tooth with 13 tooth drive what ratio should I use if any happy new year

 

[alldodge]

I opened top 22 20 tooth lower flowers reverse 28 28 drive here 17 that’s what I have with current issues now ha another Alfa drive with 22 20 on to but foward reverse 21 21 tooth with 13 tooth drive what ratio should I use if any happy new year

What did you just say :noidea:

 

[Petetrigger]

i have 1982 sea ray amberjack 25 with 350 Alfa one fresh water cooled wot 4200 to 4800 low hours on motor can only get 3400 rpms with 17 p prop went down to 13 pitch got close to wot but boat will not get out of its own way get lost in swells in ocean should I go to 21p to get power in ocean on not we’re about wot is boat to big for motor help

I have same boat with same problem top out at 3400 rpm 25 mph with 13 pitch prop what did you come up with was the outdrive wrong. I have had this boat a few yrs put fresh engine in still same carb checks out , new electronic ignition
would very much appreciate a responses
Thanks Pete

 

[GA_Boater]

I have same boat with same problem top out at 3400 rpm 25 mph with 13 pitch prop what did you come up with was the outdrive wrong. I have had this boat a few yrs put fresh engine in still same carb checks out , new electronic ignition
would very much appreciate a responses
Thanks Pete

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