few questions about a 3.0L trouble, please need sugestion.

onlyfinol

Cadet
Joined
Jul 10, 2007
Messages
7
I recently changed the impeller because it was running hot at low speed. It seems that such problem was solved after installing new impeller, but now I am presenting a new one. A little of over heating is showing when going full throttle which never happened before. At full speed the gauge used to read half way but now after installing the new impeller the gauge show a temp. about 3/4. However, the needle never reach the red zone in the gauge. It this temp. okay for the engine?
I also noticed that when I want to to turn it off after a ride the engine does not go off instantly. It keeps running with difficulty until it goes dead. does this has to do with the little overheating?
My another question is what type of spark plug are good for the OMC 3.0L engine and what is the spark plug calibration measure? I would like to do a tune-up, I need to what else should I considered to change to have the engine running smoothly as it used run. I said this because I did not have none of this issues last year. It seems to me that even though I paid the marine to do the winterized maintenance, the boat started to presented all this thing since the first time I toke to the lake this year.
I will appreciate any suggestion and advice.
 

Don S

Honorary Moderator Emeritus
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Re: few questions about a 3.0L trouble, please need sugestion.

Year?????????????
 

thumpar

Admiral
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Jun 21, 2007
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Re: few questions about a 3.0L trouble, please need sugestion.

I also noticed that when I want to to turn it off after a ride the engine does not go off instantly. It keeps running with difficulty until it goes dead.
Do you mean when you turn the key off that it keeps stumbling along? That usually means that you have carbon build up that is staying hot and the compression and this hot carbon are enough to keep it "kind of running". It is caused by running rich. Could be from a choke issue or out of tune carb.

I have not idea about the other issues, sorry.
 

Don S

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Re: few questions about a 3.0L trouble, please need sugestion.

That usually means that you have carbon build up that is staying hot and the compression and this hot carbon are enough to keep it "kind of running"

On cars, that may be the most common reason, but on the 3.0L engines in a boat, it's about the least possible reason.
The most common are below:
1. Engine idle rpm to high.
2. Not allowing allowing the engine to cool down at idle for a couple of minutes after a run.
3. Timing off way off, especially if no using the proper method. But it's hard to say without knowing what year your engine is.
 

MainstreetUSA1

Seaman Apprentice
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Jun 12, 2004
Messages
49
Re: few questions about a 3.0L trouble, please need sugestion.

Also,
You should ket us know what the old impeller looked like when you removed it. Were all the vanes intact?
 

onlyfinol

Cadet
Joined
Jul 10, 2007
Messages
7
Re: few questions about a 3.0L trouble, please need sugestion.

Thanks guy for your sugestion, and I am sorry for not posting the year.
It is a 1992, and the boat brand is a Sunbird.
Please, let me know what I can look for in order to fix this issues.
Thanks again!!!
 

onlyfinol

Cadet
Joined
Jul 10, 2007
Messages
7
Re: few questions about a 3.0L trouble, please need sugestion.

Well it looked okay, except that it was a little wearout. By the way the year is 1992
 
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