Mercruiser 3.0 lx sea trial and compression specs.

[achris]

One more thing... from reading the past forums sends a tach tool is easy to hook up positive wire to the gray wire on the ignition module. I didn't understand what or where the ground from the tach goes. just to the block?

Tacho requires 3 wires, power (form the ignition switch), ground (from the instrument cluster 'common' ground) and a signal (form the + terminal of the coil)

Is there a digital in dash tach you guys recomend thAt would be just as good as a timing tool tach? Might aswell get one and verify.

There's not one that I'm aware of that would be and 'in-dash' tacho, but maybe the other guys know of one. I'm sure a quick interweb search would reveal many options.

Motor purrs like a kitten and revs up well in nutrel.

I've seen V8 engines running on 3 cylinders 'rev up and purr like a kitten' in neutral... How the engine revs in neutral is not a good indication of much of anything.

Even the 21 pitch it bogs out slightly but doesn't stall. The 23 makes her stall out pretty easily. God kknows how old the gas is thats in there. I had 12 gallons of old gas and topped it off with 93 and a can of seafoam. Maybe the ****ty gas?

yeah, old petrol is a problem. I always recommend pumping as much of the old stuff out before adding new. Trying to mix new to 'dilute' the old is a bad idea. It's highly likely that something of the old fuel has gotten into the carb and is clogging up the accelerator pump system... That's why we're suggesting a strip and clean out...

I'm trying to run all the old stuff out and put ethanol free 90in it for winter lay up but damn thing is sipping gas. Haha what a good thing to complain about.

The 3 litre engine, correctly set up (tune and prop) is well know for being really good on fuel...

 

[Guymontag]

Thanks for the wealth of information and knowledge. I did a YouTube of the carb rebuild. I think I'm gonna have to let a pro do that my huge fubleing fingers aren't finds fit that bill. Which I was thinking If I'm gonna pay some one to rebuild I might as well buy a new one. Looks like like 300$ I can get a refurbished one on eBay. I'm sure it'll cost more for the rebuild. I saw a Weber conversion carb mentioned. Wasn't sure if that is or isn't a performance upgrade and if that's a rebuild kit that uses my existing carb with diff internals or is it a whole different carb. I don't mind dropping a few bucks into the motor. Is there a bolt on upgraded carb available for the 3.0lx?

 

[Guymontag]

P.s. hers a pic of the distributor I have on my boat is it already converted to electronic?

 

[achris]

That appears to be an EST distributor, so electronics already, yes.

The current carb is either a Rochester or Mercarb 2bbl. The Weber is a 4bbl, and can't be fitted to that engine (not easily).

There are no 'upgrades' for the 3 litre. 140hp is pretty much your lot. If you want more power, sell the boat and buy something with a more powerful engine...

Chris...