yamaha 115

[dcpcccrc]

ok i pulled off the poppit valve cleaned it up did all that just wondering how it works im quessing when the motor builds up exaust pressure it pushes that open thus letting in water i hope this is what was wrong with it it wasnt very dirty and spring moved pretty freely please help just trying to understand how this works

 

[rodbolt]

Re: yamaha 115

the incoming water enters the exhaust cover area and fills the bolock. to vent excess pressure and help maintain pressure in the block as the t-stats open and close the valve moves on and off the seat. usually its never a problem above 1000 rpm. normally it leaks at an idle and the pump cannot fill the block at low speeds.] I hope that helps.<br /> good luck and keep posting

 

[dcpcccrc]

Re: yamaha 115

ok rodbolt you seem helpful but my overheating problem is at higher rpms if thats the case then it cant be the poppit valve because at higher rpms the pressure should open the spring more so more water can go in the motor is definetly overheating after 15 sec of time it takes to plane buzzer comes on after idling for a minute after cool down buzzer shuts off. did a compresion check all cylanders are fine so its not a blowed head gasket but while the buzzer is on motor is smoking badly there is no air in the oil lines and it is getting oil and at all times the motor is peeing water cant figure this out

 

[rodbolt]

Re: yamaha 115

the poppet dumps water into the midsection. have you checked the impeller? if the t-stats are good and the pump is good your probably going to be looking at head gaskets.<br />is this boat run in saltwater?

 

[dcpcccrc]

Re: yamaha 115

no rod it isnt run in saltwater never has been i dont know where the impeller is i think its where the water goes in could it be dirty sucking in enough water to keep it cool at idle/ low speeds not sucking in enough water to keep it from overheating at high rpms i did the compression check all were good between 116 and 120 could a head gasket still be blown if all the compressions were good

 

[rodbolt]

Re: yamaha 115

well the next step is to find the impeller and replace the water pump with a new complete kit. they are about 50 dollars<br /> good luck and check the t-stats too

 

[dcpcccrc]

Re: yamaha 115

could it be the water pump even tho its peeing water sorry i am dumb founded when it comes to this thanks for the help and rather than changing the impeller change the whole water pump

 

[huanca]

Re: yamaha 115

take rodbolts advice, he´s usually right. understanding the cooling system is actually fun. you take it apart once and learn for a lifetime plus not that expensive. if engine is several years old, do the head gaskets and change the internal zincs, clean the space between cylinders and block, the head cover too and do the tstats too. you will not regret it. my impeller sheared between the hub and rubber, check yours, it should be rock solid. good luck

 

[dcpcccrc]

Re: yamaha 115

alright i pulled the poppit valve cleaned it but didnt do anything going to change the water pump but the motor is peeing water can it be the water pump since it is peeing water. just wondering it kinda seems like the stream doesnt have very much pressure comming out just wondering if the impeller goes bad will it still suck in some water

 

[tryan]

Re: yamaha 115

yes, from my experience, the impeller may be 'bad' and still get weak flow from the tell-tale.

 

[dcpcccrc]

Re: yamaha 115

thanks tom i think that is whats wron should i just change the impeller as the pressure coming out the pee hole isnt like it used to be