Merc XR4 150 BlackMax owners that have removed OI...

[Jmosselli]

Hey guys, quick question, i bought my boat at the beginning of the summer, took it out after i got it running and it ran great, this was with the oil injection still installed. When the engine was warm it would start with the bump of the key. Now i have removed the oil injection and am just premixing 50:1. The engine doesnt want to start when its warm like it did before, now i have to give it a little throttle to get it to fire even when its up to temperature. Is this normal operation with the oil injection removed and premixing? I just assumed its because the oil in the gas takes some of the flamability away or something like that?

If this isnt normal operation, where should i be looking to get it back to where it starts with the bump of the key at operating temp?

 

[tommarvin]

You have to maintain and clean oil injection, and it works great Not many people do, the motor was designed for it.
I dont know anything about removing oil injection, what I do know is NOBODY cleans or maintains there out boards much less there oil injection.
I have read that premixing is fine after oil injection removal ,
Old outboards dont hot start because when old ignition parts get hot expand they dont work till they cool down how long, 15-30 min.
Are your carbs clean like all the you tube videos? and fuel system clean?

 

[GA_Boater]

tommarvin - What videos? Can you link to some of them? Old outboard don't start like new because they old, not because ignition components get hot - If this was the case why doesn't an old motor stop when it reaches operating temps. Think about it.

J - What did you do to getting the motor running? Have you checked compression? Was the oil injection causing troubles?

 

[Dukedog]

oil injection and/or pre mix has absolutely nothin' ta do with tha tha way it starts and /or runs.. 99.9% of 'lectrics (new or old) are gonna work or not ....might wanna rethink this statement.. 'specially not being very versed on tha older V6 mercs… if something changes in tha way it starts and/or runs it will be a motor issue.. fuel, fuel delivery, ignition, adjustments...

"

Old outboards dont hot start because when old ignition parts get hot expand they dont work till they cool down how long, 15-30 min."... ​

did you remove any modules other than tha oiler module?

 

[Chris1956]

To be clear, oil injection on that motor mixes oil with the gasoline, and then pumps it to the carbs. So a premix motor (with fresh fuel at 50::1 ratio) should run exactly as well as an oil injected motor. Your issue is likely something else.

 

[racerone]

Was a new water pump impeller installed when you bought the boat ?

 

[Jmosselli]

Im going to try to answer all the questions that were asked of me but cant figure out how to quote multiple people.

To get the engine running i had to change the head gaskets. The compression was fine. The water pump was also rebuilt at that time.

The Oil Injection was functioning properly aside from the warning module wasnt working right, so instead of risking the motor, or spending $300 on a new warning module, I just decided to remove the system and premix.

I removed ALL the modules at the same time as the Oil Injection and set the timing manually.

Now that I think about it, the timing is probably the reason for needing throttle to get the motor running even when warm. Next summer when i take it out ill play with the idle timing to see if i can get it to start better.

 

[Dukedog]

yeah, idle timing, rpm needs ta be set in tha water in gear ta whatever makes both you and tha motor happy.. may/may not be what "book" calls for.....

 

[Jmosselli]

yeah, idle timing, rpm needs ta be set in tha water in gear ta whatever makes both you and tha motor happy.. may/may not be what "book" calls for.....

if my memory serves, i set the idle timing to 8* BTDC, and then adjusted it to where the motor seemed happy, but not in the water in gear. So that will be my first thing to try next summer.

 

[flyingscott]

You have to maintain and clean oil injection, and it works great Not many people do, the motor was designed for it.
I dont know anything about removing oil injection, what I do know is NOBODY cleans or maintains there out boards much less there oil injection.
I have read that premixing is fine after oil injection removal ,
Old outboards dont hot start because when old ignition parts get hot expand they dont work till they cool down how long, 15-30 min.
Are your carbs clean like all the you tube videos? and fuel system clean?

What are you talking about? So i guess you dont take care of your outboards either since nobody does. How is oil injection designed to be serviced? Maybe you should tell people how to do that or better yet put up videos on toutube. With your extensive knowledge you should have people up and running in no time.

 

[Dukedog]

if my memory serves, i set the idle timing to 8* BTDC, and then adjusted it to where the motor seemed happy, but not in the water in gear. So that will be my first thing to try next summer.

yeah, most of tha time tha "book" timin' will get ya started on tha hose and sometimes is actually what ya may end up with.. but especially with tha wh series carbs ( they have a set, non-adjustable ('cept with jet change) idle circuit in 'em) tha only right way to adjust idle is with timin' only, in real time...

ta make a statement that EVERY BODY lets their motors go ta hell ina hand basket pretty much makes ya a hack!