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1990 90hp force on 18 ft bayliner

B

bobbyrod

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does anyone know what the maxi

does anyone know what the maximum rpms at full throttle this boat should run i had it in the water on trailer and tied to dock i never saw it over 22oo is this correct or does the motor need to be moving for the rpms to go up i dont know if that is maximum rpms what kind of speed can exspect to go on this boat thanks guys
 
"Bobby, max wide open throttle

"Bobby, max wide open throttle should be 5500 rpms - 5200-5300 would be considered optimum.

Your engine is on the lower end of what you would want on that particular boat. I would expect somewhere between 28-32 mph under ideal conditions.

Is this rig new to you? did you have anyone check the motor out? it could be numerous issues causing the 2200 rpm max.

Have it looked at (or troubleshoot yourself) before you turn the motor into junk. Force are famous for eating piston rings (and trashing the motor in the process). They are also hard on CDI boxes - your motor will have 2 of them...."
 
would it have made a differenc

would it have made a difference if it is on the trailer and tied down is that why i got such low rpms the boat wasnt moving i still had it hooked up to trailer and tied to dock the motor only has 36 hrs someone told as the boat moves the rpms will go up whats your thoughts Graham Lamb Is this true i was just testing the motor it will go out this week in the water i already have my kicker and ready to work
 
"No, in fact, when timing a mo

"No, in fact, when timing a motor you can either time it at cranking speed or alternately, keep the boat on the trailer and open her up.

It will reach wide open throttle (wot) and max rpm's just fine being on a trailer. If she is only getting to 2200 rpms you have something out of whack.

First thing I would check though is the tach - could be toast, bad connection, set wrong etc and then take it from there...

And a 18 year old motor with 36 hours on it tells me a few things - never used, sat idle possibly for years at a time - possibly neglected as far as routine maint goes.

More motors die from lack of use than over use...."
 
motor runs really good starts

motor runs really good starts up easy i will no more tommorow when i put it in the water also one more question when i shift into forward it go into gear i have to keep pushing forward quite a bit before i throttling up is that normal or is my throttle messed up maybe thats why i only get 2200 rpm once i go into gear i should be able to throttle as i move it right can i get your number and give you a quick gingle thanks bobby
 
"Sounds like that could be you

"Sounds like that could be your problem - stretched cable, or out adjustment, or seizing up on you (again all signs of sitting around idle)..."
 
"Without the boat running, mov

"Without the boat running, move your shifter as far forward as you can - take the hood off the motor and see if the butterflies on the carbs are completely open. If not, you have a cable problem..."
 
this is the update i took the

this is the update i took the motor out and ran it on the water max rpms were 4100-4300 i only got 25 miles per hour the prop that was on there was a p692 another number was 692265 ? and i have a spare michigan 071030 which one should be better for speed what do these numbers mean thanks any info aprreciated thanks also is two stroke suppose to smoke so bad when in neutral when you first start up the motor thanks
 
"Bobby, I would expect a coupl

"Bobby, I would expect a couple more mph (but not alot), but your rpms are still too low for wide open throttle (and that's not good for the motor).

Swap out the prop and see what that does for you.

That Michigan wheel (that's a discontinued number now - replaced by 071035) prop is a 13 1/2D 15P (or 15 pitch prop) - I don't know what the other prop is that you have.

Just off the the top of my head, a 15 pitch sounds about right on an 18 foot (glass) rig being pushed by a 90 horse."
 
the other one does have a 15 s

the other one does have a 15 stamped on it too so i got 2 15 piitch then also could my carbs be gummed up thats why i am not getting more rpms this boat did set for 3-4years with old gas in it i drained it and put new gas with stabilizer this was the first time i have had it out in 3-4 years it idles really good but when i start giving it throttle my windshield shakes a little till get moving what is a good way to decarb this engine any ideas what is a good carb cleaner i can put in the gas thanks for the info
 
"Bobby you can try seafoam or

"Bobby you can try seafoam or any of the 2 cycle carb cleaners on the market. They don't really clean the carb out if it's clogged - that requires disassembly and a good soaking/cleaning with carb fluid - but they do help prevent a new problem.

In the spring (fast approaching now) when I "bring motors out of storage", I tank them and run about a 1/3 of a can of Mercury powertune through them. That's not exactly what the directions call for, but find that it blows all kinds of "boogies" out of the engine (especially fogging oil). It's sprayed right into the carb throat, so while it doesn't do much for the jets etc, it additionally is supposed to decarb the cylinders. Not sure exactly what it does in total, but know a big mess of crud comes out of the exhaust...."
 
so do you think that could be

so do you think that could be a possibility that carbs might be a little plugged and thats why i dont get 5200 rpms that is the original prop on that motor but who knows what the rpms where when they set it up so is it a good idea to run the motor full throttle all the time i keep hearing it is bad if your wide open and only getting 4000rpm what about just putting around just relaxing is that bad cause engine running but not at 5200 rpm well thanks again for your knowledge
 
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