rough Idle

[tino]

Can;t seen to get idle right,did the spark plug test the top and middle cylinder the rpm's droped when I took out plug the last cylinder hardly no difference.did sea foam with fresh gas still the same.any help would be very appreciative. 91/90hp yamhah tlrp

 

[rodbolt]

Re: rough Idle

maybe a bit of engine info could help us help you.

 

[tino]

Re: rough Idle

1991/90hp tlrp yamaha.

 

[rodbolt]

Re: rough Idle

test the compression, test the spark, there are some posts about making a spark tester.
if both pass open up the fuel pump and carbs.
when was the last time the engine ran correctly ?

 

[tino]

Re: rough Idle

91/90hp tlrp yamhah

 

[tino]

Re: rough Idle

she ran good all spring/summer. the sending unit in the gas tank was not working for some reason,anyway I ran out of gas,on the bay fishing call boat us got gas after that she develop a cough / sneeze manage to fix that, but still rough idle. check the thermostat, it working. put sea foam in gas tank[ build in) the gas gage started working again. still rough idle.will do the test's you said to do.thanks. tino