Warm start issues

[jbennin]

Just purchased a 2001 Challenger 1800 with an M2 240 Merc. Runs great from cold but once I stop and then try to fire it up from warm....its a struggle. The workaround is to put it into Forward quickly giving it a bit of throttle obviously not ideal. I just replaced all plugs but haven't done anything beyond. Smokes a little but not excessive and certainly not constant. Reading some temp sensor related issues so ordered a couple of replacement sensors to try. Any other thoughts?

 

[AnviL Man]

I have an 03 Speedster with the 240 EFI and mine doesn't like to start up immediately after a shut down. But I believe it to be from not venting the engine bay long enough for restarting it. I don't think it's anything else than that. The few times I've restarted it within a minute or two of shutting it off (not venting engine bay) it won't want to fire right up whereas normally this engine fires up instantly with no issues whatsoever. I could be wrong but it's something to think about, I think they recommend venting it for about 3-4 min before restarting. Although I find a good full minute works fine for me.

 

[jbennin]

I normally vent for 2 to 3 min and sometimes more. Is there some sort of protection built in that would cause it to not start after shutdown without venting?

 

[jbennin]

I also noticed it struggles to idle when in this state

 

[AnviL Man]

I had made a post about my issue with this a year ago and this was one of the responses i had received from a pro on here:

~~~More than likely it was stale air causing the issue. Boats have Bilge Fans for a very specific reason. It is to clear the potentially hazardous fumes prior to starting the engine, thus no BOOM !!!

As a side effect, there is normally so much Carbon Dioxide in the hull that the engine cant start, it needs fresh air. You will find this to be more of an issue anytime the engine is hot and up to temperature.

So,, make sure the fan works and USE IT,,, I bet this solves the issue.

 

[jbennin]

I'm wondering then if I should take a look at the fan itself and/or remove the air filters that are inline with the fan as a step? The fan does seem to work, although it probably could use some maintenance as I'm hearing it make a screech now and then. How nice would that be if it was that simple.

I had made a post about my issue with this a year ago and this was one of the responses i had received from a pro on here:

~~~More than likely it was stale air causing the issue. Boats have Bilge Fans for a very specific reason. It is to clear the potentially hazardous fumes prior to starting the engine, thus no BOOM !!!

As a side effect, there is normally so much Carbon Dioxide in the hull that the engine cant start, it needs fresh air. You will find this to be more of an issue anytime the engine is hot and up to temperature.

So,, make sure the fan works and USE IT,,, I bet this solves the issue.

 

[jbennin]

Received parts, any particular special tools I will need to replace the sensors in question? Are these easily visible for the naked eye?

 

[jbennin]

Running much better

Received parts, any particular special tools I will need to replace the sensors in question? Are these easily visible for the naked eye?

Replaced PORT side sensor along with ran venting for a solid 5 min also popped engine hatch to allow lots of air flow in between rides and the unit started very reliably throughout the day. Very happy with how it is running now.

One other question, does anyone have any suggestions as to a fuel additive? I'm currently running Marine Stabil but i'm being told to stay away from Stabil as a running additive and should look to Sea-foam.

 

[bhatch21]

Glad to hear about your engine. I just went through a bilge fan issue with my Islandia. As for the additive, I use only Ethanol Shield. It disperses water and protects fuel, you can see many videos of it in action on youtube. I would stay away from Seafoam, the cleaner type one. It has solvent properties and can break down your 2-cycle oil while the engine is running. Not good.

 

[AnviL Man]

I've only had my boat for one winter so far and I used marine stabil while it sat for several months. I am not aware of using additive for anything other than long term storage. This time around I'm going to put the marine stabil in on the last run of the season. Last year I didn't do that, I only added it in while the boat was in it's storage spot already.