Let me start. I have a 2002 Tohatsu TLDI MD50A that is acting up. I bought this outboard recently at a good price because it would not start, well; it was firing briefly but did not stay running. Was supposed to work as late as this spring when it suddenly stopped.
“-I can fix this.” I thought to myself. O boy was in for a ride. Little did I know what I was getting myself into. TLDI is definitely not a “tree shade mechanic” engine.
After reading some, well most, of the threads here and doing some research I found out the usual suspects: Battery and CCA power. Compressor/pressure in air rail, fuel delivery, TPS resetting. Ground cables.
Did a visual check and no obvious problems. Hooked it up to a brand new battery with 100Ah 860 CCA. New gas and tank. New pressure bulb. Fuel filter cleaned. Sure enough, it fires up as it would start, but that’s it.
Hooked up shop air to the Schrader valve (as mentioned in a post) and got it to stay running. The compressor is bad!
Took apart the compressor. The cylinder and piston looked good, checked reef valves and changed the gaskets. Installed it again and reset the TPS.
Now it started but was running very poorly. Dies at idle and misfire. Hard to start sometimes but goes if I help with some throttle. Checked the pressures on the rail and it is now ok. 80 psi air and 90 fuel.
Now the real troubleshooting begins.
- Changed to a DFI oil in the system as I did not know what kind of oil was in there.
- Got brand new recommended spark plugs.
- Cleaned out the VST clean and float/needle all looked fine.
- Cleaned out the FFP and changed the rubber seal.
- Compression test.
- Tested the low-pressure pump, diaphragm and seals good.
- Air intake reef valve looks good.
- Adjusted the gap on the CPS.
- Took apart the air rail and cleaned the air- and fuel injectors and checked the regulators. Tried to get the injectors professionally cleaned and serviced but there is no one doing that in my country.
- Measured resistance of all electrical parts mentioned in service manual.
The self-diagnostic do not give me a clear error message.
What am I missing? I suspect that the engine is running rich. The spark plugs are sooty and often wet after I check them. Bad air/fuel injectors? TPS fault even if measuring doesn’t indicates that? God forbid the ECU?
I have the service manual and by now I know it from cover to cover. Searched all over Internet for TLDI information, forums, videos etc. Hell, I even learned about the Optimax trying to find out what could be wrong.
Here is a video of the engine:
https://youtu.be/6JPI8vkWbP0
Sorry for the wall of text. This is my last resort. Thanks!
/Robert
“-I can fix this.” I thought to myself. O boy was in for a ride. Little did I know what I was getting myself into. TLDI is definitely not a “tree shade mechanic” engine.
After reading some, well most, of the threads here and doing some research I found out the usual suspects: Battery and CCA power. Compressor/pressure in air rail, fuel delivery, TPS resetting. Ground cables.
Did a visual check and no obvious problems. Hooked it up to a brand new battery with 100Ah 860 CCA. New gas and tank. New pressure bulb. Fuel filter cleaned. Sure enough, it fires up as it would start, but that’s it.
Hooked up shop air to the Schrader valve (as mentioned in a post) and got it to stay running. The compressor is bad!
Took apart the compressor. The cylinder and piston looked good, checked reef valves and changed the gaskets. Installed it again and reset the TPS.
Now it started but was running very poorly. Dies at idle and misfire. Hard to start sometimes but goes if I help with some throttle. Checked the pressures on the rail and it is now ok. 80 psi air and 90 fuel.
Now the real troubleshooting begins.
- Changed to a DFI oil in the system as I did not know what kind of oil was in there.
- Got brand new recommended spark plugs.
- Cleaned out the VST clean and float/needle all looked fine.
- Cleaned out the FFP and changed the rubber seal.
- Compression test.
- Tested the low-pressure pump, diaphragm and seals good.
- Air intake reef valve looks good.
- Adjusted the gap on the CPS.
- Took apart the air rail and cleaned the air- and fuel injectors and checked the regulators. Tried to get the injectors professionally cleaned and serviced but there is no one doing that in my country.
- Measured resistance of all electrical parts mentioned in service manual.
The self-diagnostic do not give me a clear error message.
What am I missing? I suspect that the engine is running rich. The spark plugs are sooty and often wet after I check them. Bad air/fuel injectors? TPS fault even if measuring doesn’t indicates that? God forbid the ECU?
I have the service manual and by now I know it from cover to cover. Searched all over Internet for TLDI information, forums, videos etc. Hell, I even learned about the Optimax trying to find out what could be wrong.
Here is a video of the engine:
https://youtu.be/6JPI8vkWbP0
Sorry for the wall of text. This is my last resort. Thanks!
/Robert