Timing problem

[jonic]

I have a 1997, Mercruiser, 4.3 LX GEN+, OK009522 serial number with Merc drive.
I think I am having a timing issue. It doesn?t want to shut off. It coughs and sputters anywhere from 3-20 seconds when it is shut off and maybe 1 out 5 times it shuts off fine. It starts and runs great just doesn?t want to shut off. I have a friend who can time cars and thinks he can time my boat without a problem. Is there a major difference between cars and my boat?

Thanks

 

[jonic]

Re: Timing problem

It is a 190 HP and says Thunderbolt ignition.

 

[Chris1956]

Re: Timing problem

Those motors sometimes do that after a hard run. I do not know if it can be fixed by altering the timing.

Try letting the motor idle for 30 sec, before shutting it off, and see if that helps.

BTW- Timing that motor is the same as timing any dissy-based ignition.

 

[mkast]

Re: Timing problem

Shutting the engine down in gear will lower the engine RPM.
What RPM does the engine idle at in neutral?

 

[jonic]

Re: Timing problem

I have tried letting it idle for awhile. Someone descibed it as "dieseling" but that did not help. I will check into idle rpm.

 

[rbh]

Re: Timing problem

good morning-
it kind of sounds like one or all of your plugs are dirty or could have a burr that holds the heat at a point that it detonates the fuel even though there is no spark, pull the plugs and inspect. are you running a colder plug?
rob

 

[jonic]

Re: Timing problem

Today my friend came over with his timing light and it looked like timing was maybe a 1/2 to 1 inch off. He did not think that would cause the problem only being a little off. We could not figure out how to adjust the timing. It was different from what he had seen before. Any suggestions?

Sitting in my driveway it turned off perfectly every time. I tried letting it run for a while, shutting it off at a fast idle, and in gear. Every time it shut off great. What could be the difference between my driveway and on the water? We did cleanup some off the connections in the distributor cap and the rotor looked good.

I am idling about 900 rpm and will pull the plugs hopefully today or early tomorrow.

 

[jonic]

Re: Timing problem

I pulled plugs and they looked bad. One had some buildup on it. Replaced them with the plugs recommended on the engine info on breather cover. Not sure what cold plugs are. Took it out and no improvement. Can the timing being off an inch or so do that? How do I adjust timing? Any suggestions? Thanks!

 

[mkast]

Re: Timing problem

When was the last time this engine was tuned up?

 

[jonic]

Re: Timing problem

No idea I just bought it a couple months ago. What is considered a tuneup? Plugs, wires, what else? I wonder if the timing is the issue even though it is not very much off?

 

[rbh]

Re: Timing problem

OK then, it sounds like the plugs were giving you the engine run on.
next, full tune up, wires, cap, rotor, change the oil motor and leg, all filters, oil, fuel etc for your boat. If old gas remove it and burn it in the lawnmower!
Or just read the tune up spects at the begining of this section for the complete run down.
rob

 

[Fun Times]

Re: Timing problem

I have a 1997, Mercruiser, 4.3 LX GEN+, OK009522 serial number with Merc drive.
I think I am having a timing issue. It doesn?t want to shut off. It coughs and sputters anywhere from 3-20 seconds when it is shut off and maybe 1 out 5 times it shuts off fine. It starts and runs great just doesn?t want to shut off. I have a friend who can time cars and thinks he can time my boat without a problem. Is there a major difference between cars and my boat?

Thanks

More then likely the reason it is dieseling is the rpms at idel is way to hi at 900 that engine needs to idel at at 640 rpms. Look at the bolt that would hold the [dist] down and tight it should be painted black, dose it look like a wrench has broken the paint away at all, You would see a silver look to it at the edegs of the bolt if some one has messed with the timing from the past. Other then shuting it down dose the engine run and sound good at the top end no pings or knocking or back fireing here or their? If no then the timing MIGHT be ok. If you get time open this link up and look at post #15 it will help you aujust your idel in detail. and tell you what eles to look for, It is long.http://forums.iboats.com/showthread.php?t=313610

 

[jonic]

Re: Timing problem

I dropped it off at local shop after talking to them about the timing and they thought it was off enough to cause problems. I also asked them to adjust idle. I just picked it up and they timed it and said once it was timed the idle dropped down to where it needed to be. I hope to put it in the water tomorrow and see if it fixed. If not I will start pursing the other suggestions. Thanks for the help!

 

[jonic]

Re: Timing problem

I put it in the water yesterday after having it timed and it had no power. I could not go over 3400 RPMS and it still did not shutoff correctly. Also, the starter went out and I had to get towed back to dock, good times!. Anyway it is back at shop getting timing double checked. I will post soon what I find out.

 

[zinc]

Re: Timing problem

I would be checking what the engine water temperature is,
If she's running hot after a hard run, like the water pump is not up to snuff,
The plugs will be incandescent (glowing) do to lack of cooling around the plugs and cause the running on that you describe.
Not a good thing

 

[jonic]

Re: Timing problem

Water temp is always good around 175. Local shop said timing was off and retimed it. They said they must have not tightned something down. Took it out and it ran great except under heavy load, like pulling 4 person tube with boat load, it made a high pitch rattle in motor. This was a new sound. I have a friend who said it is still a timing issue. He thinks timing is close, but under a hard load it not quite in. Anyone agree? I am tired of taking it back to same guy about timing. It shut off pretty good too.

Thanks!

 

[bruceb58]

Re: Timing problem

I am thinking that if it is a 1997 it has the Thunderbolt V ignition vs the IV and needs to be set in base timg mode to set initial timing. Do you know if they did this?

 

[Fun Times]

Re: Timing problem

I am thinking that if it is a 1997 it has the Thunderbolt V ignition vs the IV and needs to be set in base timg mode to set initial timing. Do you know if they did this?

how old is the gas, should do a new fuel filter, and new oils, And grease up every thing, pull drive off for service also [ect]

 

[Don S]

Re: Timing problem

I am thinking that if it is a 1997 it has the Thunderbolt V ignition vs the IV and needs to be set in base timg mode to set initial timing. Do you know if they did this?

I would also be checking the knock sensor system to make sure it's working.
Not sure what pulling the outdrive and greasing things up will do to stop pinging under load.

 

[Fun Times]

Re: Timing problem

I would also be checking the knock sensor system to make sure it's working.
Not sure what pulling the outdrive and greasing things up will do to stop pinging under load.

It just sounds like this boat needs a good check up is all