My Setup - Frustrated!

[Falcon]

So here I am with a great setup on my boat (2011 21' Thunder Jet Chinook), a 225HP Yamaha Four Stroke and a HT 8HP Yamaha kicker. Main engine, love it! But I'm more than ready to get rid of my 8HP POS kicker. I can't get three trips out of it before it fouls up, it just won't stay running. I've had Mark Shubrook pull the carb apart to see what the heck is going on with it, but still only get two trips out of it before it gums up again. I'm using mid-grade 89 octane fuel in the boat, kicker runs off the main fuel tank.

I'm thinking of getting into the tuna fishing, thus I'm considering two 115HP four strokes with no kicker. Anyone else having trouble with their 8HP HT kickers?

 

[Fish Assassin]

Mine was a POS till an adjustment was made by popping the little factory plug on the side of the carb and turning it up.

 

[Battle Bay]

What do you mean by gums up? Is it fuel that is gumming up?

 

[Sr SQ]

After my last 3 boats with yammi kickers I vowed to never own another boat with one....
Even though I only had troubles with two of the yammis I hated them all for their inability to preform their job on the rough and windy days.
This time around I went with a twin motor set-up and will never look back.
IMHO that would be a perfect rig with the 115s, they just sip the fuel idling and you will have a real charging system for those high demand days.
You can troll with one and alternate to keep the hrs down if thats important to you.
No more troubles steering one way on the windy rough days.
You will be able to plane at a slower speed for the days you need to slog thru the nasty stuff and a way better hole shot from the extra traction compared to a single.

Down side is a little less top end (with the same hp) and higher maintenance costs but the costs aren't a lot because you still need to maintain the kicker.

Win, win

 

[1stLite]

I have the same kicker I have had it for 10 yrs now thousands of hours on it not one problem.

 

[Sharphooks]

Wow, never heard any one dis a Yammie HT before.

I've had two 8 HT's and one 9.9 HT and all three ran like sewing machines. The only problem I ever had was some coughing on cold starts....AND, I should add, one of my 8 Hp HT developed problems like you're describing.

If you've stripped the carb and it still has intermittent issues, my guess is it's a gummed up diaphragm in the fuel pump.

I replaced mine and it ran like a champ after that---my suspicion---E10 ethanol --- I didn't have a fuel filter on that kicker and paid the price---when I opened up the fuel pump it looked like a frog had been detonated and pasted on to the diaphragm. Swapped it out and problem solved.

here's the schematic:

http://www.boats.net/parts/search/Yamaha/Outboard/2005/T8PLHD/FUEL 1/parts.html

have a look at Part No. 21:

66M-24471-00-00
DIAPHRAGM

good luck

 

[Sitkaspruce]

I had the same motor, no problems for 5 years. I did have a fuel filter between the main tank and motor and changed it every year. It did start rough a few times on cold mornings, but 99% of the time first or second pull. Only problem I ever had was the tiller arm seizing up, removed it, cleaned it up and greased it, worked well after that.

Nice boat by the way!!!

Cheers

SS

 

[Falcon]

Wow, never heard any one dis a Yammie HT before.

I've had two 8 HT's and one 9.9 HT and all three ran like sewing machines. The only problem I ever had was some coughing on cold starts....AND, I should add, one of my 8 Hp HT developed problems like you're describing.

If you've stripped the carb and it still has intermittent issues, my guess is it's a gummed up diaphragm in the fuel pump.

I replaced mine and it ran like a champ after that---my suspicion---E10 ethanol --- I didn't have a fuel filter on that kicker and paid the price---when I opened up the fuel pump it looked like a frog had been detonated and pasted on to the diaphragm. Swapped it out and problem solved.

here's the schematic:

http://www.boats.net/parts/search/Yamaha/Outboard/2005/T8PLHD/FUEL 1/parts.html

have a look at Part No. 21:

66M-24471-00-00
DIAPHRAGM

good luck

Thanks for the info, appreciated! I'm guessing it's the fuel pump because I've had the carb apart twice.

 

[Falcon]

I had the same motor, no problems for 5 years. I did have a fuel filter between the main tank and motor and changed it every year. It did start rough a few times on cold mornings, but 99% of the time first or second pull. Only problem I ever had was the tiller arm seizing up, removed it, cleaned it up and greased it, worked well after that.

Nice boat by the way!!!

Cheers

SS

Thanks...I'm thinking a combination of filter and fuel pump. I've maybe got eight hours on the things and had it serviced twice already, just disappointing.

 

[Falcon]

I don't think it's the fuel, I'm burning mid grade 89 octane gas. As I mentioned above, I'll get it serviced again but if it doesn't work this time I'm done with it.

 

[wolf]

ill give you 100 bucks for it....been using yammys for close to 30 years now all have performed well and I can service myself (most times) what do you mean by "gummed" up what EXACTLY is it happening?? very weird.

Wolf

 

[the fog ducker]

I replaced the crappy little Fuel filter with a larger capacity one ,Generic brand , WAY CHEAPER , and reliable..its a 2005 yamaha t-8 , up until this year , ZERO problems ,
afters spending hundreds of dollars trying to get my motor running more than 5 - 10 minutes , i popped the cowling off ,
drained the gas bowl , it has a flat blade screw ya back off a few turns ta drain , then tapping my carb with my bonker a few times : )... it ran fine again for 10 20 mins , we changed the needle and seat after the bonker test lol... ( cheap ).. apparently this has been an issue with these motors ? minor !!!again , Zero problems since ive owed it !!.... runs perfect again , Yes there is a factory sealed mixture screw that can be drilled out , believe its just a rubber plug ( for emissions purposes ) remove that , and you can adjust this now , when the motor is running , back this screw off until its running at a high rpm ( richer ) , then start ta thread it back in ( lean er out ) , just until the idle slows a touch , then back off a tiny bit , ur golden , this $20 fix , cost me alot of grief this year , runs like a dream again , hope this helps,,

dont give up on the motor , as mentioned , runs like a sewing machine , you will love it...

fd

 

[Falcon]

ill give you 100 bucks for it....been using yammys for close to 30 years now all have performed well and I can service myself (most times) what do you mean by "gummed" up what EXACTLY is it happening?? very weird.

Wolf

$100 bucks, you're such a kind soul

Mark Shubrook was the one who said he had to clean the carb up as it was "gummed up", I didn't ask for an explanation. Just thought I'd ran into some dirty gas. But I took the carb apart last night, cleaned it good, same issues today. Thus I'm thinking it's the fuel pump? I don't know anymore, but I did hook up a nice spring today!!

 

[Falcon]

I replaced the crappy little Fuel filter with a larger capacity one ,Generic brand , WAY CHEAPER , and reliable..its a 2005 yamaha t-8 , up until this year , ZERO problems ,
afters spending hundreds of dollars trying to get my motor running more than 5 - 10 minutes , i popped the cowling off ,
drained the gas bowl , it has a flat blade screw ya back off a few turns ta drain , then tapping my carb with my bonker a few times : )... it ran fine again for 10 20 mins , we changed the needle and seat after the bonker test lol... ( cheap ).. apparently this has been an issue with these motors ? minor !!!again , Zero problems since ive owed it !!.... runs perfect again , Yes there is a factory sealed mixture screw that can be drilled out , believe its just a rubber plug ( for emissions purposes ) remove that , and you can adjust this now , when the motor is running , back this screw off until its running at a high rpm ( richer ) , then start ta thread it back in ( lean er out ) , just until the idle slows a touch , then back off a tiny bit , ur golden , this $20 fix , cost me alot of grief this year , runs like a dream again , hope this helps,,

dont give up on the motor , as mentioned , runs like a sewing machine , you will love it...

fd

Thanks...I appreciate the insight, I'll give it a try and see what happens. Cheers

 

[CIVANO]

I had a pin hole in the diaphram of the fuel pump and it only leaked after an hour or so of running or at least it took that long to run crappy. I finally saw the sheen on the water on a flat day and shut it down and replaced it. Another issue can be the thermostat. If stuck open it is hard to start and actually causes the oil level to rise with fuel addition. These engines stall with too much oil. I had both problems. Check the oil level with the dip stick and see if it increases.

 

[profisher]

If you are running any of the new 4 stroke kickesr without a proper inline fuel filter water seperator you are asking for problems. The idle circuits are so small on these engines that the tiniest piece of grit will plug them up. Buy yourself a spin on canister type filter and replace the canister each spring...they are only just over $10. Fuel pumps and t-stats will give you problems as mentioned if they are faulty.

 

[the fog ducker]

BANG on , agree , filters are a MUST... no one expects water or debris in there fuel , IT HAPPENS , protect ur investment ,
get good separators on board , its cheap insurance !!

fd

If you are running any of the new 4 stroke kickesr without a proper inline fuel filter water seperator you are asking for problems. The idle circuits are so small on these engines that the tiniest piece of grit will plug them up. Buy yourself a spin on canister type filter and replace the canister each spring...they are only just over $10. Fuel pumps and t-stats will give you problems as mentioned if they are faulty.

 

[braydonnelson19]

Try changing the plugs in the engine

 

[Cuba Libre]

Buy a Mercury LOL!

 

[Falcon]

Buy a Mercury LOL!

Suzuki now makes a fuel injected 15HP, I'm thinkin that's the ticket