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F40TLR headache, What did I get :(

atti_mac

New member
I just bought a boat 4 weeks ago, and took it out few days back, and it wasn't pleasant .. First it didn't want to start, finally started but it had very low idle, and when I pushed in gear died off. I took it home, got new sparks .. NGK.. same thing.
I tried to move around the spark plug cable, and voila started idling better!
So I started unplug the top cylinder spark plug to check if the cylinder works, and after i pulled it , rpm dropped, so the 1st ok!. The second plug was pulled and no change in the idle , so 2nd cylinder won't work. Lower cylinder works , so 2 of 3 is good. I swapped around the cables and ignition coils ( I hope they are same) , and I got a same result. 1,3 good. 2 won't fire.
According to the previous owner, and the invoice I got from him, about 4 months ago he had a same issue, and a shop replaced the CDI unit ( charged him $600) and new carburetor kits, new gas, bulb, etc.. So he paid $1800... The motor started on his driveway when I bought it, but I have this issue now.. Again.. I checked a label on the CDI, and it shows 2009! The motor is 2007, so either they ordered an old part was sitting in a warehouse somewhere or they screwed him over ( and me ) with a used CDI..
I can't bring it back there ,( I won't trust them..) and I was wondering if you guys would have any idea what can be wrong . I will take it to a mechanic this weekend, but I was wondering if any of you was facing with similar problem..
I also downloaded a wrong service manual by accident, I have a pdf format for Worldwide: F40BMHD, F40BWHD, F40BED, F40BET and Usa, Canada:F40MH, F40ER, F40TR, if someone has by the chance the F40MLH Service manual: LIT-18616-02-16 I would willing to trade mine :)

My boat doesn't have a tachometer , and I would like to install one, and i was hoping if i will found out info about that in the manual , also looking for a procedure to "link and sync the carburetors".
Please help me out .
Thank You!
Attila
 
Actually, I would bring the engine back to the service shop the previous owner used. Bring the invoice with you. And unless they ask I don't see a reason to tell them you are the new owner of the engine. But even if they figure out you are not the same owner, the fact remains they performed service on your engine only 4 months ago to fix the problem you are currently experiencing. Perhaps you'll catch a break and they'll be an honorable business that stands by their service. You have nothing to lose if they they will not be helpful.

A new CDI does cost around $600. But the '09 manufactured date on the CDI installed on your motor does not imply it was used. It is plausible it sat on the shelf for years. This is one of those unfortunate mistakes made by used outboard motor consumers. Never buy a motor without testing it under load, unless you're buying it for parts or expecting it to have issues. Of course knowing this now doesn't help you now. But at least it will in the future should you buy another used motor.

Can't help ya out with the manual. And the carb sync and timing procedure is located in the manual. However, the manual you accidentally downloaded has this procedure listed, despite you having a different model. I'd bet its the same procedure used to time and sync your carbs.
 
I can't bring it back to them.. I don't trust them , and they are 3h away. They charged $200 to get rid of 5 gallon old gas from the tank, and they didn't even clean the gas tank. That type of mechanic shop they are. The cost of CDI cost less than $400 online btw.. I was able to fire up the cylinder 1 and 3 now, so it is running under load. My local mechanic looking in to it today. Will know more by end of the day.
 
I was able to fire up the cylinder 1 and 3 now, so it is running under load

FYI, an outboard engine under load means the engine is turning the propeller against resistance, such as a submerged vessel through water. Resistance being the key factor, as it relates to load. In essence, in order to adequately assess the performance of your engine it needs to be run in open water. Starting and running the engine by using muffs or submerging the lower unit into a bucket of water does NOT load the engine.

Comparing the engines performance under load to its performance when not under load would be similar to the comparison of you leaning up against a wall (no effort on your part) to you pushing against a wall (effort applied on your part). Let's say you've got a bum leg and you're leaning against this wall. Those observing you would not know you have a bum leg. But once you push against the wall using your bum leg as force (engine), those observing would know.
 
I was able to fire up the cylinder 1 and 3 now, so it is running under load.

Did you run the boat/motor in open water to determine it's "running under load"? To be considered under load, the motor needs to thrust against resistance. Running the engine on muffs or in a bucket does not load the engine.
 
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I just bought a boat 4 weeks ago, and took it out few days back, and it wasn't pleasant .. First it didn't want to start, finally started but it had very low idle, and when I pushed in gear died off. I took it home, got new sparks .. NGK.. same thing.
I tried to move around the spark plug cable, and voila started idling better!
So I started unplug the top cylinder spark plug to check if the cylinder works, and after i pulled it , rpm dropped, so the 1st ok!. The second plug was pulled and no change in the idle , so 2nd cylinder won't work. Lower cylinder works , so 2 of 3 is good. I swapped around the cables and ignition coils ( I hope they are same) , and I got a same result. 1,3 good. 2 won't fire.
According to the previous owner, and the invoice I got from him, about 4 months ago he had a same issue, and a shop replaced the CDI unit ( charged him $600) and new carburetor kits, new gas, bulb, etc.. So he paid $1800... The motor started on his driveway when I bought it, but I have this issue now.. Again.. I checked a label on the CDI, and it shows 2009! The motor is 2007, so either they ordered an old part was sitting in a warehouse somewhere or they screwed him over ( and me ) with a used CDI..
I can't bring it back there ,( I won't trust them..) and I was wondering if you guys would have any idea what can be wrong . I will take it to a mechanic this weekend, but I was wondering if any of you was facing with similar problem..
I also downloaded a wrong service manual by accident, I have a pdf format for Worldwide: F40BMHD, F40BWHD, F40BED, F40BET and Usa, Canada:F40MH, F40ER, F40TR, if someone has by the chance the F40MLH Service manual: LIT-18616-02-16 I would willing to trade mine :)

My boat doesn't have a tachometer , and I would like to install one, and i was hoping if i will found out info about that in the manual , also looking for a procedure to "link and sync the carburetors".
Please help me out .
Thank You!
Attila

Did you ever resolve your issue? I have the same Yamaha 2007 F40TLR and had similar issues in the last 2 years. I just rebuilt my carbs 1 1/2 years ago the motor was running fine with on issue that the motor always had which is acceleration from idle. I have to feather the throttle to get it to a higher RPM. However two days ago I was out fishing and felt a bump and heard a slight clunk. The RPMs dropped and the motor stopped and wouldn't start.
Thank god for my trolling motor.
At home I removed the carbs and saw they were a little dirty again so I cleaned them which didn't help. I've replace the plugs and now going to diagnose the spark and check compression.

I saw where some guys have modified there jet sizes, I have order mine and I will try the same approach to correct the throttle issue.

I'm curious what your fix was. thanks
 
However two days ago I was out fishing and felt a bump and heard a slight clunk. The RPMs dropped and the motor stopped and wouldn't start.

Bump and clunk, followed by rpm reduction to engine stall....these are not signs of a motor experiencing dirty carbs or fuel, poor spark or compression. I'd be checking your lower unit. Start with draining the gear oil into a container and look for metal shavings. The gear oil screw cap is magnetic, so look there for shavings. And of course if the gear oil is milky color, there's your problem.
 
Further troubleshooting has proven No spark. All 3 coils are within spec.

Bump and clunk, followed by rpm reduction to engine stall....these are not signs of a motor experiencing dirty carbs or fuel, poor spark or compression. I'd be checking your lower unit. Start with draining the gear oil into a container and look for metal shavings. The gear oil screw cap is magnetic, so look there for shavings. And of course if the gear oil is milky color, there's your problem.
 
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