Mercruiser 350 EFI---wont start

[Rinkerguy24]

HELP please..............took it to the lake last week and it ran great..fri evening it would not start it would just turn over.got towed in..i was 2 hours from home next morn took it to a local and he tried it and it started right up. took it out mid day did the same..towed in.. sunday tried it out of water, fired right up let it get warmed up, turned it off and on several times, finally it would not start just turn over , called that local he said try starting fluid it fired right up..let it run a bit and tried it again same thing no start....pulled top cover and looked, it looked completely dry like it was getting no gas..pulled gas line at back of carb and gas is getting to there.. seems the only thing i can figure out is its not shooting gas out of injectors when key engages, give it some starting fluid, it starts up fuel flows great from injectors...whats the deal??????

 

[Uraijit]

Re: Mercruiser 350 EFI---wont start

How do you have a carb on an EFI system?

 

[Maclin]

Re: Mercruiser 350 EFI---wont start

From your description it sounds like you have a TBI (throttle body injection) engine. Post back with the year and engine model# and serial# if you can, also what as done on the last full tuneup and when it was.

Some engines have oil pressure safety circuits for the fuel pump, some have more than one fuel pump (low and high pressure for MPI). Some have other safeguards, so there could be a flaky sensor,switch or sending unit. That is why you need to give the specifics on your year, model# and serial# of your engine.



Basics can apply across the board though....:

• Look at your operator's manual and follow any troubleshooting steps given.
• Check the battery(s) with a load test. EFI computers have to have the right voltage to be brainy enough to boot up.
• Check the battery connections and the other ends as well, both + and - terminals and leads.
• Remove water separating filter(s) and pour contents into clear container and see what settles out after a few minutes. Replace all filters.
• Have a shop run the codes from your computer.

 

[newport dave]

Re: Mercruiser 350 EFI---wont start

its not shooting gas out of injectors when key engages, give it some starting fluid, it starts up fuel flows great from injectors

The injectors won't pulse when the key is turned to the "on" position. The fuel pump should come on for two or three seconds, but the injectors won't supply fuel until the ECM receives an ignition reference signal (during cranking).

If the injectors don't pulse during cranking, it may be due to a low voltage condition, as maclin suggested.

 

[Rinkerguy24]

Re: Mercruiser 350 EFI---wont start

Yes it is a TBI engine #OL660058. I did replace the fuel pump a month ago and it was one of the ones that is called cool fuel where the lake water cools it before it enters the engine.. When i took it to that local he did notice that the groung terminal had broke loose and he fixed that.

The boat is a 2000 Rinker 243 Siesta deckboat w bravo III.. I have had it for 4 yrs and it had 9 hrs when i bought it, now it is like 65hrs. as far as any tune up i have done nothing but change fluids regularly...

I have not had the voltage checked by machine, but it seems to be charging at 13-14 on the dash, battery has a fresh charge..

And as i said above we used the boat all week last week until fri when the problen began, only thing i remember doing diff was i stopped at the marina and got abt 40 gallons of gas because it was getting low for the evening, dont know if that had anything to do with it or not.....

 

[Limited-Time]

Re: Mercruiser 350 EFI---wont start

You can dump a little gas down the throttle body and see if it fires. If it does you have a fuel delivery issue. Just be sure you replace the flame arrester be for you try and fire the engine..................Just in case of a back fire.

 

[Windykid]

Re: Mercruiser 350 EFI---wont start

A set of noid lights would go a long way in trouble shooting this. When it wont start, put noid light in line with injector. If there is no pulse, I would look at the ignition module in the distributor. That what tells the injector to fire.

 

[Rinkerguy24]

Re: Mercruiser 350 EFI---wont start

I got a set of noid lights from a friend that plug into the injectors, is that what you are talking abt.? have not had a chance to try it yet..

Pouring gas into the carb would be the same as statring fluid , right??

 

[Limited-Time]

Re: Mercruiser 350 EFI---wont start

Yes, but the engine is designed to run on gas. Starting fluid can be hard on them.

 

[newport dave]

Re: Mercruiser 350 EFI---wont start

If I understand you correctly, you have the flame arrestor off and your looking at the injectors. You start to crank the engine and it won't start and there is no fuel coming from the injectors. Then you prime it with a can of quickstart and crank it again, it starts up and continues to run and you can see that the injectors are now shooting fuel into the throttle body. Is this correct?

If it is correct, then I would think that the problem may be that when cranking before using the quickstart, the voltage was too low for the injectors and/or ECM to function. Then, when you add the quickstart, it's able to start and the voltage comes up and the engine runs normally. Anyway, you might want to try replace or at least have your battery tested.

 

[Don S]

Re: Mercruiser 350 EFI---wont start

I'm with Dave. An engine cranking to slow WILL NOT start an EFI engine.
Hook your test voltmeter up to the battery and try to start the engine. What does the meter read while you are cranking?

 

[Rinkerguy24]

Re: Mercruiser 350 EFI---wont start

dave, you are absolutely correct..thats exactly what it does....

 

[Rinkerguy24]

Re: Mercruiser 350 EFI---wont start

finally got a chance to try some things.....battery shows 12 v on meter, under load holds at 10 volts..normal correct??
on the meter with boat running does not register in the charging area, it is below...means alternator not charging...correct??????

am not able to get it to NOT start so i---turned everything on(acc.) let it run boat gauge shows 11 volts sat there and ran fine... turned it off left everything on trying to pull down battery, fired right up.......after 10 minutes..

let it set for 35 minutes everything off, like i was at the lake but w out the radio, started right up so turned it off and on a few times knowing it would do it anytime, finally about the 3rd time it did it....would not start , wife was watching the water and mentioned lots of smoke coming out and smells like gas, that now tells me flooded..??? still wont start as of then....but i guarantee it will fire right up in the morn.......

so is it that i am not getting the gas to the carb? or voltage to low to prime it? or the gas is not burning off and it is flooding me, preventing startup.....

getting frustrated with it!!!!!! also noticed when i took the spark arrestor off that there was small beads of......gas or water all around the top off the carb wiped some of it up it smells like gas but beaded up like water???????

 

[Maclin]

Re: Mercruiser 350 EFI---wont start

If the exhaust smells like gas then gas is getting into the cylinders but not firing. Do you try opening up the throttle when this happens? I know I have had a fuel injected engine flood on me when the injectors did not close and opening the throttle worked to get it started until I could get it back to the dealer. Once it was running it seemed to run ok, but if it sat for 30 minutes or so after it had been running it acted just like an old carbed engine flooding.

I would now take the water separating fuel filter off very gently and pour the contents into a clear container just to see what settles out. This would be to check that the 40 gals. of Marina gas did not introduce water or other contaminants into the tank.

 

[Rinkerguy24]

Re: Mercruiser 350 EFI---wont start

i will go do that right now......yes i did try to start it at wide open throttle and at half no start just lots of smoke......by the way just noticed you are in overland park..was there abt 3 mos ago visiting wifes friend and her hubby, they moved there abt 3 yrs ago.....

 

[Maclin]

Re: Mercruiser 350 EFI---wont start

We just moved here a year ago this month, we are close to Hiway 69 and 151st, don't know too many people yet. We were in Wichita most of the time up 'till then.

 

[Rinkerguy24]

Re: Mercruiser 350 EFI---wont start

well here is what i just dumped out of the water fuel seperating filter......

 

[Rinkerguy24]

Re: Mercruiser 350 EFI---wont start

what the hell is in my gas?????????

 

[Maclin]

Re: Mercruiser 350 EFI---wont start

Wow, I was expecting maybe a clearish bubble of water....yuck!

Whatever it is, your fuel injection system and your engine do not think it is fuel that's for sure.

I would contact the Marina and see if anyone else has had some bad gas symptoms or complaints.

 

[Rinkerguy24]

Re: Mercruiser 350 EFI---wont start

when i poured it into the glass it was all mixed up and the gas looked horrible, then after a minute or so it all settled..i guess this is an unusual amout of water?????