what is throtle friction

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funkenfresh

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Feb 14, 2009
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hi all.. ive got loads of qestions as im new to boat motors..
but on my forward controls i have a turn knob labled 'throtle friction'..
could this be the cause of my motor spitting and sputering, (and not do a full speed at full forward on the foward controls). after 5 minutes run time in the water? when its out of water and attached to the hose.. is runs fine.. ive been told that the carbs might need a good clean... but it seems wierd how it runs good out of water and after 5 mins in water it gets all choked up..
 
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Rick.

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Re: what is throtle friction

What year and model are we talking about here? Throttle friction is just an adjustment that stops the throttle from moving on it's own and would not be the cause of your problem. "Attached to the hose" you have no load on the motor so it isn't a fair comparison. Let us know. Rick.
 
mthieme

mthieme

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Re: what is throtle friction

Throttle Friction is an adjustment to 'tighten' the throttle so it will stay and whatever position you desire.
This has nothing to do with the running of the motor outside of setting the speed.

In the water you have a load. Not knowing anything about the motor, I can only recommend generically to go through the fuel system. Check the lines for cracks, stiffness, loose fittings - anywhere that it could suck air, check primer bulb for dryrot cracks - does the primer bulb get hard? - is the arrow in the right direction? On down the pike there is the fuel pump, a filter (hopefully) and finally the carb. The fuel pump and carb have rubber parts that don't last forever.

What model & year is it?
 
Mas

Mas

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Re: what is throtle friction

funkenfresh said:
but it seems wierd how it runs good out of water and after 5 mins in water it gets all choked up..
Click to expand...


The engine will behave differently in the water vs. out because the exhaust does not flow freely out while in the water...the exhaust must push the water out of the way to get out thus creating back pressure. You will notice the your boat will idle differently in & out of the water. This is normal!

Likely, your carbs are gunked up and may need to be rebuilt. If the motor has not been run regularly, they will gum up...count on it!

How old is your fuel?

You will also need to check your plugs to make sure they're relatively clean and gapped to specs.

Just some advice on where to start,

MAS
 
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funkenfresh

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Re: what is throtle friction

thanks guys i will check all of your suggestions.. the motor is a 1976 seahorse 70 hp.. i have noticed fuel spitting out through a small hole (1mm) wide in the back of the fuel filter.. (which is on the motor), everytime i throtle..
 
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F_R

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Re: what is throtle friction

No wonder it doesn't run right. You have to find and fix the cause of that fuel leak.
 
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funkenfresh

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Feb 14, 2009
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Re: what is throtle friction

but i still dont understand why it would run good for about 5 minutes and THEN start going ****!?!?!?!?! this is what confusses me? anyway im thinking a rebuild kit might be in order..?
 
R

Rick.

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Re: what is throtle friction

That small hole leaking gas. That could be your problem. I doubt it is on a filter like you say, it could be coming from the fuel pump but I don't know. No matter, gas should not be leaking from anywhere and when it isn't leaking it could be sucking in air which will make your motor run rough. Get a manual so you can identify the parts properly. The manual will be a big help in any repairs you feel confident enough to tackle. I would say a carb. kit would be a good start but the gas leak would be the first priority for me. Best of luck. Rick.
 
F

funkenfresh

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Feb 14, 2009
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Re: what is throtle friction

im sorry guys to keep posting and trying to get more answers but its summer here in West Oz, and i really want my boat.. itll take 4 weeks to get a service book for my motor..
heres some pics to help those who are familliar with my motor (a 1976 johnson 70hp)

DSC00149.jpg


DSC00152.jpg



this picture shows the 1mm hole that fuel spits out of while running. which could be the possible or definate cause of my motor stuttering..

DSC00153.jpg


does this help anyone.. is there a part missing from the 'FILTER'? whats the posibble fix?
 
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