yamaha under whater?

[tommijommi]

hello my engine have been under see whater<br />now i get it to run but not as it supose to run <br /><br />when its runing it caming fire out the air on the intake<br /><br />wht coud bee the probleme???

 

[tommijommi]

Re: yamaha under whater?

this is an yamaha 80 four stroke

 

[DJ]

Re: yamaha under whater?

Did it go under while running?<br /><br />If so, you probably bent a valve, or worse.

 

[tommijommi]

Re: yamaha under whater?

no it was not running<br /><br />and the have not been whater in the oil<br />only salt whater in the intake an some eletric parts..

 

[DJ]

Re: yamaha under whater?

By your description, it sounds like it is backfiring.<br /><br />Several thinks can cause that, on a four stroke.<br /><br />1. Very rich or lean mixture(s).<br /><br />2. Ignition timing off.

 

[tommijommi]

Re: yamaha under whater?

when i cleaned my intake i have to take out the mixture wrench on all the 4 intake how can i adjust<br />all the 4 intake right again???

 

[tommijommi]

Re: yamaha under whater?

Originally posted by DJ:<br /> By your description, it sounds like it is backfiring.<br /><br />Several thinks can cause that, on a four stroke.<br /><br />1. Very rich or lean mixture(s).<br /><br />2. Ignition timing off.

can it backfiring if it get to litle gass ??<br />do you now a way i can chek this ??

 

[DJ]

Re: yamaha under whater?

Tommy,<br /><br />I'm not familiar enough with that particular engine to give you mixture advice. I do not even know if it is EFI or carbureted.<br /><br />Yes, a lean mixture can make the engine backfire or "sneeze" back through the intake.<br /><br />I would also highly suspect timing. Since it was submerged, the electronic may be way off.

 

[rodbolt]

Re: yamaha under whater?

hello most the f80's are carbed. I cant remember<br />anything else. did this sink in saltwater? if so remove the airbox assy and look for sand in the carb thraots. if you have sand stopnow and sissasemble and clean the engine.however to just get it running drain and flush the water from the fuel pump filters and carb bowls. the bowls have drains, flush well with gas but wash the spilliage off as its flamible. test the spark with the plugs out.if all four are sparking its a good sign.wash the entire powerhead with fresh water. do this with the battery dissconnected.spray some fogging oil or other light oil down the carb shutters and crank it over some. double check that the oil level is correct and not contaminated. if you suspect the timing is to far advanced and its possible if the TPS is damaged by saltwater you can start it with the TPS dissconnected but timing will be locked about 7* btdc or so. your idle will be funny. after it all is running you will need to remove the flywheel and drive gear sprokets to clean the salt out. also the timing belt tensioner will most likely fail. dont wait till it does change it. post back if you have any other questions.

 

[tommijommi]

Re: yamaha under whater?

Originally posted by rodbolt:<br /> hello most the f80's are carbed. I cant remember<br />anything else. did this sink in saltwater? if so remove the airbox assy and look for sand in the carb thraots. if you have sand stopnow and sissasemble and clean the engine.however to just get it running drain and flush the water from the fuel pump filters and carb bowls. the bowls have drains, flush well with gas but wash the spilliage off as its flamible. test the spark with the plugs out.if all four are sparking its a good sign.wash the entire powerhead with fresh water. do this with the battery dissconnected.spray some fogging oil or other light oil down the carb shutters and crank it over some. double check that the oil level is correct and not contaminated. if you suspect the timing is to far advanced and its possible if the TPS is damaged by saltwater you can start it with the TPS dissconnected but timing will be locked about 7* btdc or so. your idle will be funny. after it all is running you will need to remove the flywheel and drive gear sprokets to clean the salt out. also the timing belt tensioner will most likely fail. dont wait till it does change it. post back if you have any other questions.

I HAVE TRIAIED TO START THE ENGINE with the TPS dissconnected. THE ENGINE SOUNDS LIKE THE SAME . WHEN THE TPS IS BROKEN IS IT COMING FIRE OUT THE INTAKE THEN??

 

[rodbolt]

Re: yamaha under whater?

hello<br /> if its been this long and its still not running its time for a complete engine teardown and inspection. the shiny metal parts inside will rust rapidly. nothing I can do . hope your on good terms with the local dealer.

 

[tommijommi]

Re: yamaha under whater?

Originally posted by rodbolt:<br /> hello<br /> if its been this long and its still not running its time for a complete engine teardown and inspection. the shiny metal parts inside will rust rapidly. nothing I can do . hope your on good terms with the local dealer.

BUT THE ENGIN IS STARTING and runs but there is some back firing and i dont know wat to do?<br />coud it be somthing wrong whit the intake?

 

[rodbolt]

Re: yamaha under whater?

if it runs there are 3 normal causes for a backfire in the intake. 1 is a lean fuelmix due to water/debris in the carbs. will require a tear down of the carbs. 2 is a missfire of the ignition. easy to find. that motor uses a waste spark ign. index the flywheel and see if the correct cyls fire at the correct time. going by memory,(be careful it fails)the top coil fire #1 and #4 simultaneously. so you can index the flywheel and use a timing light to see if spark occurs on the proper cyl at the proper time. #3 reason is an intake valve is open/off its seat when the spark occurs. need a leak down test to find it as a compression test may not. its not voodoo nor black magic. all the subsytems need to work correctly or the system as a whole does not work. is it possible that you crossed the plug wires? they should be labled 1-4 they do not plug in in a striaght line from top to bottom. the cylinders are 1,2,3,4 from top to bottom, but the coils dont cross from top to bottom.

 

[tommijommi]

Re: yamaha under whater?

i havent crossed the plug wires. they are marked 1-4. <br /><br />i will check teh timing whit timing light and check the compression.<br /><br />then i will come back to you<br /><br />thanks for the help <br /><br />best regards tommy

 

[tommijommi]

Re: yamaha under whater?

Originally posted by rodbolt:<br /> if it runs there are 3 normal causes for a backfire in the intake. 1 is a lean fuelmix due to water/debris in the carbs. will require a tear down of the carbs. 2 is a missfire of the ignition. easy to find. that motor uses a waste spark ign. index the flywheel and see if the correct cyls fire at the correct time. going by memory,(be careful it fails)the top coil fire #1 and #4 simultaneously. so you can index the flywheel and use a timing light to see if spark occurs on the proper cyl at the proper time. #3 reason is an intake valve is open/off its seat when the spark occurs. need a leak down test to find it as a compression test may not. its not voodoo nor black magic. all the subsytems need to work correctly or the system as a whole does not work. is it possible that you crossed the plug wires? they should be labled 1-4 they do not plug in in a striaght line from top to bottom. the cylinders are 1,2,3,4 from top to bottom, but the coils dont cross from top to bottom.

can you please explaine my what an: leak down test is?<br />i m not sure what you mean

 

[rodbolt]

Re: yamaha under whater?

hello<br /> when you check the timing the top coil fires both plugs at the same time. check the timing with both wires. you should see the same marks on the flywheel. make a mark(if not already on the flywheel) 180* from the #1 TDC mark. then check the timing on the lower coil wires. should see the 180* mark on the lower two wires. if you see anything else check the connections on the coil primaries. its possible they were crossed.

 

[tommijommi]

Re: yamaha under whater?

Originally posted by rodbolt:<br /> hello<br /> when you check the timing the top coil fires both plugs at the same time. check the timing with both wires. you should see the same marks on the flywheel. make a mark(if not already on the flywheel) 180* from the #1 TDC mark. then check the timing on the lower coil wires. should see the 180* mark on the lower two wires. if you see anything else check the connections on the coil primaries. its possible they were crossed.

hello i have checked the ingnition timing whit the tps pluged in the timing was litle above 7*

 

[tommijommi]

Re: yamaha under whater?

what is the timing supose to be whit the tps pluged in ?

 

[tommijommi]

Re: yamaha under whater?

Originally posted by tommijommii:<br />

Originally posted by rodbolt:<br /> hello<br /> when you check the timing the top coil fires both plugs at the same time. check the timing with both wires. you should see the same marks on the flywheel. make a mark(if not already on the flywheel) 180* from the #1 TDC mark. then check the timing on the lower coil wires. should see the 180* mark on the lower two wires. if you see anything else check the connections on the coil primaries. its possible they were crossed.

hello i have checked the ingnition timing whit the tps pluged in the timing was litle above 7*

the timing its changing from 0* to 7* when you give trotle<br /><br />what coud it be?

 

[bigbrownbuku]

Re: yamaha under whater?

start by cleaning your carbs tommi. no you cant do it yourself. they need to be setup with an intake vacuum tool, engine running. if this doesnt work move on from there.