motor runs-on...then wont start

[95caravelle95]

hi all,

i have 95 caravelle with 3.0l lx inline 4 cyl. last week on the lake i turned it off and it dieseled (ran-on) for about 10 seconds. then it wouldnt start. i got it back home and the timing was waaay off.

i pulled the distributor and plugs and set motor at #1cyl TDC aligned the distributor, set timing and it fired right up. problem fixed.......

until today


i take it back to the lake and we ride around for a couple hours, starting and stopping it without any trouble about 10 different times or so.

last time i turned it off, it ran-0n again for about 3 seconds, then it would not starrt back up again. i had to loosen the dist. and turn it while my wife turned the key. finally got it to idle, tightened dist. down and brought it home.


ANY IDEAS AT ALL????? it runs good untill it diesels, if it ever diesels when you shut it off it wont start back up without turning the distributor.



sorry so long but i really need some help with this.

 

[Don S]

Re: motor runs-on...then wont start

When it diesels, it blows the gas out of the engine and sucks water back into the cylinders. The water WILL NOT fire.
I would bet you have the Delco EST distitributor, you need to put it into base timing mode to set the timing, if you don't you will soon be pulling the head to replace the head gasket or perhaps the engine if this is allowed to go on.

Also read the Service bulletin I posted in this thread.
http://forums.iboats.com/showthread.php?t=213129

 

[95caravelle95]

Re: motor runs-on...then wont start

don,


after the last trip to the lake i came home and checked it.without being in base mode it was about 4ATDC. i set the motor at TDC realigned the dist., put in base timing and set it at 1BTDC. when i took off the jumpers it auto advanced to about 10-12BTDC. it ran fine all day, until the one time it dieseled when i turned it off then it would not start without me turning the dist. how can the timing jump like that from the motor dieseling?

also, it sounds like there is a exhaust leak, low in the bilge, towards the back. any info on something like that?

thanks

 

[Don S]

Re: motor runs-on...then wont start

when i took off the jumpers it auto advanced to about 10-12BTDC. it ran fine all day, until the one time it dieseled when i turned it off then it would not start without me turning the dist.

Are you sure the timing changed? Cold be the engine had some water in it and eventually it started. You just happened to be messing with the distributor. Next time it won't start after dieseling, check the cylinders and spark plugs for water. If none, take your timing light, put it in base timing mode and check your timing. If it moved, then you probably have a bad ignition module in the distributor. But I doubt it.

 

[95caravelle95]

Re: motor runs-on...then wont start

dumb question......is it bad to have water in cylinders...???!!! wont that blow a head gasket trying to start a motor with water in it? when the boat is in motion now you can smell exhaust fumes bad. and there is a kinda "ticking noise" coming from below the motor behind the oil pan where the exhaust goes thru the hull into the outdrive. Im pretty sure its an exhaust leak, but it just started today after the dieseling problem. is an exhaust leak in this area normal for these boats and how expensive/time consuming is it to fix?

 

[Don S]

Re: motor runs-on...then wont start

A few drops of water can foul a plug and keep it from firing, a lot of water can hydroloc an engine and keep it from turning at all. Possibly bending the rods and blowing a head gasket. An exhaust leak BELOW the water, will let water in the boat. The exhaust is water cooled and under water.
How expensive and time consuming depends on what is wrong......... Do you know exactly what's wrong? If not, then you can't say what it's going to take to fix.

 

[95caravelle95]

Re: motor runs-on...then wont start

don,

this noise, that i believe is an exhaust leak, is coming from inside the engine compartment either in the water or in my driveway you can hear it inside. the only reason i believe it to be an exhaust leak is the fumes you can smell...bad...and the noise sounds like an exhaust leak on a car. i cannot feel the leak i can only hear it. its coming from low in the bilge area on the back side of the motor where i cant reach. the fumes are to bad to stick your head down there while running.

as far as hydro lock, when it diesels and wont start it just acts like its not getting spark. there is NO hesitation during cranking.


how hard is it to take the head off and look at things??

 

[95yj]

Re: motor runs-on...then wont start

There's not a lot of places for the exhaust to be leaking assuming that none of the cast hardware has a hole in it which is unlikely. You have a couple of elbow joint boots and the exhaust bellows. Unless the clamps on the boots weren't tight and the dieseling slid them off, you've probably ripped the exhaust bellows. Probably time to replace all your bellows. You really need to get in there and find the problem, otherwise you're going to have to pull the drive and take a look from that side.

 

[Don S]

Re: motor runs-on...then wont start

you've probably ripped the exhaust bellows. Probably time to replace all your bellows.

The exhaust bellows could be completely missing, and it won't have any affect on inside the boat. It in no way cause the ticking "below the motor"

Right at the top of the exhaust tube that attaches to the bottom of the transom shield, is an exhaust shutter. It may be causing the ticking.

 

[95yj]

Re: motor runs-on...then wont start

Thanks for the correction Don. It's nice to have folks like you keep the rest of us honest while we keep learning.

 

[95caravelle95]

Re: motor runs-on...then wont start

i took the outdrive off this morning. there is some gear lube in the u joint bellow and it looks like about a whole tube of marine grease covering the gimbal bearing. is that normal?

I also took the exhaust apart inside the boat. the flappers are rubber right? the move very easily and look in good condition. Im thinking its either coming from where the bottom most exhaust tube connects to the hull or maybe its something in the u joints?????

before i removed the outdrive, with it running in my driveway, i moved the outdrive from left to right with my hand. i heard a loud noise when moved to each side all the way. it sounded like the u joint spinning hitting the casting or something.


im so upset with all this and im about to put a 4 sale sign on it if i cant figure this out. im running out of money to dump into this thing.

 

[BAYLINER185]

Re: motor runs-on...then wont start

when you ran the motor in your drivway did you have the outdrive tilted down far enough?

It is not a good idea or even recomended that the engine be run with the drive at certain angles and if you exceded those angles I beleive it is possible that you would hear the U joints rubbing in the outdrive shaft chamber.

On the tickign note: I had a ann 84 webcraft w/ 3.0 Mercruser and from tiem to tiem when I had problems starting the engine and it would crank quite a bit it would also make a ticcking / tappign sound comming from where you are describing this sound. I was told one time that it could be the oil pump but the sound would seem to go away after the engine would get started and the oil preasure would climb to normal so I really dotn know for sure what the noise was.

Im intrgued though about the exhaust leak as my boat would take on quite a bit of water when running and especially when it was stopped. I changed all the belows and check them all a few times EXCEPT the shift boot! So it eaither had a leak in that boot or now from reading this possibly an exhause leak that let wat in the bilge area.

I would like to know what you find out the tappign ticking to be in this case as it may have been the same problem on my old boat.

I sold it 10 years ago to get married......Im since then divorced and now as of 2 weeks ago have a brand new 07 BAYLINER!