new toy to me

[mallluslitteria]

i got this boat by trading two broken toro lawn tractor, it needs little work and the motor idles just fine but bogs when throttle it up and then it dies , i have checked the carb and it has been previously rebuilt by someone else, i think it has been done by a boat dealer because all of the stuff on the motor is new like fuel lines, other than that a clean motor, it needs some upsolery work like carpeting and seat. i also have checked to see if it has been synched up with carb and timing and it is but for giggles, i took off the timing advance link it revs up in gear just fine but when i move the timing base link to advance it bogs n dies, does it mean i got a bad timer base ?? i have checked carbs like 4 times all clean .. also dumped out the gas in tank put it in fresh gas in it .. just dont want to spend the money that if it is not the problem if ya need to know the engine it is 1978 evinrude 70 hp i think the boat is a ms 1500 if i am correct ?

[fastdonzi.]

Seems like you are tracking down the problem. Around here you'll be expected to mount a 225+HP Motor and report back with the results, However if you search you will probably find where it has already been done. Welcome to Scream and Fly.....That's what it's all about

[mallluslitteria]

Seems like you are tracking down the problem. Around here you'll be expected to mount a 225+HP Motor and report back with the results, However if you search you will probably find where it has already been done. Welcome to Scream and Fly.....That's what it's all about

well of course that is one of the main reason why i am coming on here to see if i can hang some serious hp on it lol for now i am just poking around see what i can find for the next motor i mount it to..

[bigbore]

That's an easy fix,very common,take the fuel pump off plug the pulse limniter hole,get a holley red fuel pump I like it on a on off swithch on the dash but u can wire it to ignition on from control box if u like,grnd n go,mount as low as possible (floors fine)

[Schramer]

If you have no way of checking the timing just move the timing arm at idle with the carbs staying shut and see if it revs up. Thats a good start and if it does then see if it dies before you open the butterflies....at 3k, or higher, in neutral with the timing above 20 degrees it will run the carbs outta fuel shortly if the supply is lacking.

[mallluslitteria]

humm now that you have mentioned it schramer. i have moved the timing base arm to wot setting it didnt rev up with the carb in closed position..

[Schramer]

BOOM....one less step in the diagnosis process! It should rev up quite a bit, but at a minimum, at least a little! Test the stator too. If the timing is at/around 0 degrees at idle and you move the butterflies it should rev up but be sluggish...if there is a load while in the water in gear it will never get on plane or will even die if the butterflies are opened too much.

[mallluslitteria]

mmmm....you said it should rev up a bit while the carb is closed as in not opening the butterfly.. and it didnt even rev or idle up but when i move back the timer base back to back to its original place back i touch the carb throttle linkage it revs up but as i moved timer base to advanced (wot)
while i am on the throttle it goes blahhhhhhhhhhhhhhhh then dies moved back the timerbase back it revs up ..
and how do i test a stator? to think of it i should be using timing light instead of by feeling of the engine to see if it idles up a little faster when i do this test method.. i myself is deaf since i was 3 years old due to high fever.. and a friend of mine has commented, how the hell do you hear the motor reving up. i told him in that case i can tell by feeling it but not the engine sound changing though unless i am riding in a jet boat or a fountain boat lol , thank you very much for pointing me the right direction this site is very helpful.

[Schramer]

Ya I would get a timing light involved so you can see what is happening instead of trying to feel it....honestly, I know a few peeps that are deaf and they can do some things that no one could ever imagine just by using their other senses soooo much better! Maybe you might be able to tune a mota better than most (hearing) folk just due to that fact! I'd speculate it is a timing advance situation but you saying that it revs better at 0 degrees that at 20ish at wot seems fishy unless the trigger is wigging out and doing crazy stuff so test it and look at what it is doing and report back! Also the stator can be tested by looking at the ohms by the way of a meter but I do not know the specific number, and to be totally honest, I have ran some old crap before and have never had a working stator fail. Maybe I've been lucky but I would speculate the trigger before the stator any day...just my .02!

[mallluslitteria]

i think so too as well i myself can build 300+ hp sled by using mixture of jetski parts and sled parts i can even reach 400 hp in theory i havent tested it yet .. i myself is thinking of slapping turbo on it and could tune it by feeling what the engine is doing and i could feel the harmonics of engine balance like when you nail the throttle the dynamic of harmonic dramatically changes before it even registers the tach or by sound. and you are right about that now on the boat subject lol i am going to go that route.. and i also havent thought of possibly a key sheared it a little and timing could be a wee bit off like key being bent. so i will get in there soon as i find myself a puller and check all those componets out im hoping its the trigger or the base itself is in wrong direction ?? dont know for sure though i will report back and ill poke around to get those specs for stators and timer base

[Instigator]

i got this boat by trading two broken toro lawn tractor,

love it!

[mallluslitteria]

yeah i know! i was like nice boat needs a bit of tlc the transom is solid, so is the floor and i plan to stick bigger motor in later down the road
i figure if i want to touch 50 mph out of it i would need maybe 100 or 115 hp... but for now fix what i have on there maybe sell it to get bigger better boat i am actually looking for ski boat but i was told by someone that my boat is a ski boat which i find it hard to believe and afterall its 14.5 foot boat ??

[Schramer]

Take the flywheel nut off and you can see the key and keyway without pulling the flywheel....it would run terrible all the time if it was off and I never heard of a 3 cyl stock OMC shearing the key lol...get at it!!!!

[mallluslitteria]

it can happen if the nuts are not torqued it correctly the only thing i could think of one way to shear a key dont ask me if i know lol
I will get at it in day or 2

[mallluslitteria]

OK updates!!!! it is sheared flywheel key.... now going to order new one and i dont need to mess with timer base ..