Mercruizer Alpha 1 3.0 sluggish..extremly when under load

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

I had a friend (auto mechanic shop owner) tell me to remove the air cleaner and dump 1/2 can of sea foam down the carb. let it sit overnight and in the morning remove all spark plugs and crank the engine over to expel the solution out of the engine...
If I do this, will I break anything, or will it come out alright??
Or should I never listen to anything the auto mechanic friend says again???

Is there any way to remove the carb and soak it in something overnight to get stuff out of it, or is this a ludicrous idea?

Thanks for the input.
Darrin

 

[achris]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

What your friend is suggesting is not a silly idea. It's to loosen and remove carbon build-up in the cylinders, but I doubt that's the problem here. Have you put a timing light on the engine and made sure you are getting the correct advance?

Just do as he suggested and remove the plugs and blow it all out. Any left in the carb will not be a problem. Just put the plugs back in and start the engine. It will be quite smoky for a minute or so, then it should be back to normal...

Chris....

 

[Chef Shawn]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

Leaning towards fuel filters here, but it won't matter if the engine isn't timed correctly. Pouring Seafoam down the carb is not a cure-all, but by all means, give it a shot, it's only $7 a can. If you can run at idle/low speed, but not more, check ignition system. All the gas in the world won't make you go without spark.

 

[Cptkid570]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

1. You can run it off of a gas can if you really think it is a fuel or anti-siphon or water separate issue.

2. Have you done a compression check?

 

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

Got a dwell meter...but I'm confused...
It says "for 4 cyl double the reading for 8 cyl engines" ???
HELP

 

[scarpint]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

I didn't see it mentioned, and perhaps it's a long shot, but have you checked your alternator/charging system? Just picked up my boat today which has been running rough intermittendly on-plane. Did everything I could so took it in for repair and the mechanic noted the alternator would charge only occasionally. New alternator installed and am going to drop it in the lake tonight and see how she goes.

 

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

I don't think it has anything to do with the charging system...Volts are good on the gage on the panel...

NEED TO KNOW HOW TO READ MY DWELL METER (it only has 6 and 8 cyl engine scales on it)
Picture is several posts up this thread.

Thanks

 

[fishrdan]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

NEED TO KNOW HOW TO READ MY DWELL METER (it only has 6 and 8 cyl engine scales on it)

Like the meter said on the front, for a 4 cylinder engine, double what the 8 cyl scale reads. IE: 16* on the dwell meter 8cyl scale = 32* for your 4 cyl engine.

As achris asked, is the mechanical advance working in your distrubutor? If you turn the rotor by hand, does it snap back smoothly, is it sticking? The springs and weights can rust up and stick, causing the symptoms you mentioned. Remove the rotor, the 2 screws holding down the points plate, the points plate, then see what the springs and weights look/feel like. They should move in-out smoothly...

 

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

As achris asked, is the mechanical advance working in your distrubutor? If you turn the rotor by hand, does it snap back smoothly, is it sticking? The springs and weights can rust up and stick, causing the symptoms you mentioned. Remove the rotor, the 2 screws holding down the points plate, the points plate, then see what the springs and weights look/feel like. They should move in-out smoothly...

I did not realize that was how you checked the advance...I will do this though. Will WD-40 be a good cleaner for the advance or is carb cleaner or something else needed?
My plans are as follows:
clean the inlet filter to the carb, ensure plug gaps are correct, install the new points I just got, dwell it, time it, set fuel mixture, get in the water and set the idle speed...
Can you think of anything that I have missed?

Hopefully that will solve the problems I am seeing.

 

[fishrdan]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

I did not realize that was how you checked the advance...I will do this though. Will WD-40 be a good cleaner for the advance or is carb cleaner or something else needed?

That will tell you that the mechanical advance is free, and should be working.

To "check" the advance you would need an advance timing light and run the engine through the RPM range and see if the timing is advancing as it should, you would need the timing curve for that though. Or take the dizzy to a old school shop and have them test/tune the dizzy on a distributor machine. Though,,,, this is probably overkill for what you're doing.

get in the water and set the idle speed...

And idle mixture... play with idle mixture and idle speed to get it idling smoothly.

 

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

And idle mixture... play with idle mixture and idle speed to get it idling smoothly.

I need some pics of the carb and the screws...and what they do.
Engine S/N is OC519387

 

[achris]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

 

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

Working on the boat this morning in the yard...

Looking for a service manual. Manual #6 seems to fit me best...Any ideas?

Mercruiser 3.0 Alpha 1
Model-MCM 3.0L
S/N-OC519387

 

[achris]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

#6 is for the drive, for the engine you need #10

Drive manual
Engine manual

Chris.........

 

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

Plugs gaped, points replaced and then set by feeler gage (and then with a dwell meter), timing set (see note below), fuel mix set, idle speed set. We will see how it does in the water later today, tomorrow, or Sunday.
It does run and start good in the yard though.

When timing, the notch did not line up with the timing marks at all. I even tried putting the clamp on the other 3 plug wires one at a time...Still didn't line up. If I had to guess I would say that at 1000 rpm timing was 16 or so BTDC.
I turned the dizzy until a bad run, then the other way until a bad run and split the difference. (I can imagine the posts this will generate about the pros not timing by ear, so why do I think I can). I didn't know what else to do.

Suggestions?

 

[fishrdan]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

If I had to guess I would say that at 1000 rpm timing was 16 or so BTDC.
I turned the dizzy until a bad run, then the other way until a bad run and split the difference. (I can imagine the posts this will generate about the pros not timing by ear, so why do I think I can). I didn't know what else to do.

Suggestions?

You need to get idle the RPM's down to 600 or so, so you can time the engine. At 1000RPM the dizzy's weights and springs are kicking in and the ignition is advancing.

Oh yeah, don't time it by ear, unless you want serious problems.

 

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

Cleaned the filter in the inlet of the carb, plugs gaped, points replaced and then set by feeler gage (and then with a dwell meter), timing set (see note below), fuel mix set, idle speed set. We will see how it does in the water later today, tomorrow, or Sunday.
It does run and start good in the yard though.

When timing, the notch did not line up with the timing marks at all. I even tried putting the clamp on the other 3 plug wires one at a time...Still didn't line up. If I had to guess I would say that at 1000 rpm timing was 16 or so BTDC.
I turned the dizzy until a bad run, then the other way until a bad run and split the difference. (I can imagine the posts this will generate about the pros not timing by ear, so why do I think I can). I didn't know what else to do.

Suggestions?

 

[fishrdan]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

What RPM is the engine idling at, you said 1000RPM twice, so not sure if that's your idle RPM or....??? The engine should not idle at 1000RPM or it will cause problems with the drive, eventually.

Sounds like the balancer has slipped. Turn the engine over until the engine is at TDC on #1 piston and see where the timing marks are at. You'll need to use a piston stop and rock the engine over forward-reverse to see where the TDC is actually at on the balancer (half way between where the engine stops, on the piston stop). Or place a non-metallic rod into the sparkplug hole (I used an old fiberglass tent pole) so you can rock the engine back-forth to see exactly where TDC is at. You may need to re-mark TDC on the balancer, small file and some white paint, though if the balancer has slipped, it should be replaced.

 

[dswi]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

What RPM is the engine idling at, you said 1000RPM twice, so not sure if that's your idle RPM or....??? The engine should not idle at 1000RPM or it will cause problems with the drive, eventually.

Sounds like the balancer has slipped. Turn the engine over until the engine is at TDC on #1 piston and see where the timing marks are at. You'll need to use a piston stop and rock the engine over forward-reverse to see where the TDC is actually at on the balancer (half way between where the engine stops, on the piston stop). Or place a non-metallic rod into the sparkplug hole (I used an old fiberglass tent pole) so you can rock the engine back-forth to see exactly where TDC is at. You may need to re-mark TDC on the balancer, small file and some white paint, though if the balancer has slipped, it should be replaced.

Engine is idling at about 800 or so. What should it be? I was timing at 1000. Is this right or wrong? The manual seemed elusive as to what idle rpm should be (or maybe I just didn't read far enough...)

Newbie question...what is the best way to hand turn the engine to find TDC?

 

[achris]

Re: Mercruizer Alpha 1 3.0 sluggish..extremly when under load

Engine is idling at about 800 or so. What should it be? I was timing at 1000. Is this right or wrong? The manual seemed elusive as to what idle rpm should be (or maybe I just didn't read far enough...)

Newbie question...what is the best way to hand turn the engine to find TDC?

Yep, very elusive... Hidden really well in the manual I gave you the link to, on page 3 of section 1B, Maintenance... :lol:

Those engines can be a bit of a pain to try and turn. The best way I've found is to remove all the spark plugs and while pressing on the fan belt (to tighten it up in the grooves), turn the water pump pulley. Sometimes it's a bit stiff, so I use a screwdriver with a square shaft and put that across a couple of the pulley bolts to turn it.

As for timing it the way you did? Errr, no.... do it the right way. If the balancer has slipped, then replace it...

Chris.........