Logo
FULL SITE MENU

1984 30 OMC blowing smoke

A

ajmartin67

Member
"i have a 1984 3.0 OMC, the pr

"i have a 1984 3.0 OMC, the problem that i am having if it is even a problem, is that when i start it up, it blows alot of smoke and i mean alot, after about 10 minutes it seems to clear up, i ran a compression test and all 4 cylinders are about 120lbs, is that normal? i looked at the exhaust on the back of the boat and there is an oily film coating everything. can you help me please"
 
"it's normal for it to be

"it's normal for it to be smoky if it does truly clear up.

Ok hows it run after the choke opens up.?

How does the oil look, is it over filled?

4 quarts is what i take. with a new filter.

Ok hows the plugs look.

Hers a link that will help you read the plugs?

http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html

120 is ok compression.

Where is the exhaust oily film should be only exhausting out thru the center of the prop.

You do know you can't run a stringer except with the drive fully down and water going to the drive.

Fuuly down on the water or a garden hose, doesn't matter fully down.

Finally want to post a pic with this oily film on the back maybe i can understand better, i have the same drive and motor as you."
 
"ok so the plugs look to be oi

"ok so the plugs look to be oil fouled, the oil in the crankcase looks good and clean. when i start the motor up it runs somewhat rough and then after several minutes it starts to run smooth, when i had it on the water the last time in the summer, is when all this started to happen, but when i ran it, it ran rough and once everything got good and hot, everything ran smooth."
 
did you look at the link. You

did you look at the link. You need it tuned and timed.

Carb set up right. And use mr43t AC or champion RV8C.

I like the Ac's. Never had a problem with them.
 
If not mistaken specs have bee

If not mistaken specs have been changed to RV8YC?
This to reduce fouling and improve idling particularly on raw water cooled engines.
To me the main problem seems to be leaking valve seals/broken oil deflector rings on valve stems. It might even be a choke issue.
Carb clean/rebuild might be a good thing to do.
 
"ok so assuming the carb is ok

"ok so assuming the carb is ok, how does one fix leaking valve seals or broken oil deflector rings on valve stems would that require a whole new head? or just new valves, guides, etc?"
 
Just off with the head and a &

Just off with the head and a 'normal' valve job.
All parts needed normally supplied if you buy a 'head gasket kit'.
 
"Moten is correct as always IF

"Moten is correct as always IF a full tune up is performed and the motor is timed right and the condition continues.

But what troubles me is such good compression numbers.

Maybe you just need a complete tune up, and the motor timed correctly.

25 year old piece of iron these motors are bullet proof thats why i love em'

Good luck !"
 
"just sounds like the choke is

"just sounds like the choke is sticking on... it can be adjusted. loosen the 3 screws on the choke cover. don't remove the cover, just rotate to add or subtrct spring tension. watch the choke plate during warm up."
 
"If memory has not left me com

"If memory has not left me completely, there is one thing often forgotten in the choke system.
A channel from the choke spring housing going into the carb. This operates, by vacuum, a small piston that may get stuck from carbon build-up. Be sure the channel is open and clear and piston is moving freely."
 
Back
Top