hot starting

[gruppert]

Suzuki 40 horse 4 stroke. When I run hard for 10 or 15 minutes and stop for 15 or 20 minutes the motor pops immediatley and kicks out the bendix, but doesnt start. I have to wait until motor is cold before it will start again. Any ideas?

[boats.net]

Don't know what model you have but check your local dealer for any updates that may need to done on it, some models needed a new hose kit for that kind of problem. Try idling engine for a few minutes before shutting off to let engine cool down to see if helps.

[artdf175]

since no one else has really responded
how old is the motor?
I would check the cooling system to be sure it is working okay
have you pulled the thermostat? would check to be sure it is not all plugged with 'stuff' and overheating the motor..
sounds like a vapor lock.. but don't know the other details of this motor

[gruppert]

hot starting

1999 DF40 Motor would sound overheat warning even though not hot. Dealer pulled head and cleaned water channels $850.00,same problem. Then water pump $150.00, same problem. I had been saying faulty sensor all along and disconnected it myself. Runs great except for starting problem after running for a while and the motor is still warm. Water spraying out during operation barely luke warm and can lay hands on motor si it isn`t running hot. Does the disconnected sensor have anything to do with warm starting?

[gruppert]

Don't know what model you have but check your local dealer for any updates that may need to done on it, some models needed a new hose kit for that kind of problem. Try idling engine for a few minutes before shutting off to let engine cool down to see if helps.

1999 DF40 model. Have spent over !,000.00 with dealer to clean water channels, thermostat.water pump to solve overheat warning going off even tho motor was not hot, luke warm water discharge & could lay hands on motor. I kept saying faulty sensor and finally disconnected myself. Motor runs great except for problem starting when warm.Could disconnected sensor affect this?

[Harper]

Well the forum is back up and running, I see. It was down for most of the afternoon.

To answer your question, yes, it matters that your sensor is unplugged. The ECM needs to know the engine temp to know how much fuel to inject, and bases the injector pulse width on a number of factors, including engine temp at start. With the sensor disconnected, you are showing infinite ohms to the ECM, indicating that it is extremely cold. In this instance the ECM, if it allows the engine to fire at all, will have a very long pulse width at the injectors, thinking that it is like -40°C or some such thing, and will flood the engine. More likely, though, it will show a fault in the connection to the sensor and prevent the start altogether, because what it reads is too far out of norms when compared with inputs from other sensors. If you think the temp sensor has gone bad, you should replace it. I don't think it costs very much.

[gruppert]

Thanks for the response. After talking to a few other people I decided to replace sensor, unfortunatley it was corroded and broke off in the threads. Will I be able to drill it out and maybe use an easy out without causing any internal problems?

[Harper]

Well hopefully it will work. Just be careful. An overnight soak with a good penetrant might help get it out.