Help with a 1991 Welcraft 186 Mercruiser 4.3 apha1, Starting the engine?

[starwriter]

Hello everyone!
I have a 1991 Welcraft 186 with a Mercruiser 4.3 Alpha 1 Engine.
Very hard to start.Seem's I have to crank & crank the starter overbefore it will start.When it do'es finally start.It runs fine after warming up a little.If I shut it off & turn it back on,starts right up.But,if I shut it off and leave it off for 5-15 minutes.Back to the same thing hard to start.Darn near run the battery dead before it starts.Seem's starving for fuel.
At the fuel line conection at the fuel tank.I found a connection fitting with a ball bearing inside it.I hear it's to prevent fuel siffaning.I removed it and replaced it with a standard air fiitting connection without the ball bearing.Because,at the begining of working on this boat I wasn't getting fuel.Thinking the ball bearing was either stuck or my manual fuel pump wasn't strong enough to move the ball bearing to get fuel.
I feel what's going on is,
When the engine is not running the fuel flows back into the tank.

But,would it completely empty the float bowl in the carb?(This is a standard 2 barrol carberator).
(I need to replace the fuel connection fitting at the fuel tank)Is this why it's hard to start?
I don't see a fuel filter other then the one in the carberator.I was thinking of installing a inline fuel filter before the carberator.Thinking that a inline fuel filter has a one way flow.Would this help prevent gas fuel draining back into the tank?

Last,
as I stated I have a manaul fuel pump.On the top of the fuel pump I see ,looks to be a adjusting screw for the fuel pump.What is this adjusting screw for?More or less fuel?If so,I need this fuel pump to pump better/more fuel.
I understand I have more then one question here.I thank you for any help & thoughts!Thank you!Dan.

[grarrsmi]

Are you putting your shifter in neutral and giving it a little gas to start it until it is warmed up? There is also another fuel filter you are missing. It is in the bowl of the fuel pump. Loosen that bolt on the bowl and the bowl will come out. Replace filter and rubber gasket every year. This may also take care of starting problem. Good luck

[Failproof]

The anti siphon valve is needed. If your fuel line were to leak with it removed, you could empty the tank into your boat. What kind of pressure and vacuum is your pump providing?

[starwriter]

In reply :
Are you putting your shifter in neutral and giving it a little gas to start it until it is warmed up?O yes it's battle a fight.
In relpy:
There is also another fuel filter you are missing. It is in the bowl of the fuel pump. Loosen that bolt on the bowl and the bowl will come out.
My fuel goes from the tank to the fuel pump.No filter in between.
The manual fuel pump I have looks like it has a upside down metal cup with two brakets holding it down.On top of that cup thing I'm talking about is a adjustment screw of some kind.Or is that where the filter is your talking about?I've never seen a manual fuel pump have a filter installed inside it is why I ask?The only filter I find is in the carberator it self.
In reply:
What kind of pressure and vacuum is your pump providing.
I haven't checked.The fuel pump seems to take for ever to pickup fuel why I think it's hard to start.I think the fuel is draining back into the tank from setting.From not having that valve fitting on the tank.Does this sound correct?
With the anti siphon valve removed still seems hard to start.But,when it does start runs great.The problem is after the engine is not running for a short while hard to start again.Understanding the anti siphon valve is a safty thing.Shouldn't a inline filter do the same?A inline filter has a one way flow(>).I was told to find out if the anti siphon valve is bad?Is to bypass it to see if the engine starts up without it.And the engine does start up without it but,takes many cracks to start up.Darn near run the battery dead trying.That how bad it is.More like if I had a prime ball I wouldn't have this problem it seems.
So,what one is saying is there is a filter inside the manual fuel pump?I hate to tear the pump apart to find no filter is all.
I think what I'm gonna do is replace the anti siphon valve with a new one.Install a inline fuel filter.Then,if that still doesn't work I think it's time for a new fuel pump.Can I use a standard car manual fuel pump on this motor?I was told these 4.3 Mercruiser alpha 1's are Pontiac engines.
I don't see what would be the difference between a car manual fuel pump over a boat manual fuel pump?

[starwriter]

It only starts in neutral.I have no throutle control.If I try to apply throutle ,the starter will stop as a safty thing.
What I do is move the throutle back & forth a few times as if pumping the throutle before starting.After around 10 times of doing so then it will finally start.I'm thinking all the gas drains back into the tank from setting for a long time.Is why I have dry starts.Seems the fuel pump takes for ever to pump the fuel as well.What I don't understand is,The gas in the float bowl is draining out as well?Is this possable?

[grarrsmi]

The other filter is in that bowl on the fuel pump. Unscrew the screw you think is the adjusting screw. Bracket will loosen up and bowl will slide out. There is a filter, rubber gasket, and a spring in there. Do that before adding anything else to your boat or testing the fuel pressure. There is many web sites for you to look at parts diagrams. If you look at them you will understand how it comes apart.

[grarrsmi]

Also to give it gas in neutral, you have to pull shifter out than give it gas.

[achris]

First thing I would do is a compression test, then I'd make sure the ignition system is in good shape... check for good healthy spark, check the distributor cap and the rotor, new spark plugs, check (set if necessary) the timing, maybe new plug leads (including the coil HT lead). Then, I would move on to the fuel system....

Chris.....

[fmalott]

i had the same problem as you are having i have a 2bbl on my 470. now this is not the perfect solution i cut some corners ( yea guys it's not safe bla bla ) the check valve stopped working replaced with a shut off valve as for the carb once it started it ran great shut it off it would start right away if i leave it for a period of time it would not start until i poured fuel in the carb this is where i realized my check valve was not good. i rebuilt the carb same thing no fuel in the bowl after leaving it for a period of time so instead of dealing with the problem i put a primer ball on the fuel line so now when i get in the boat i prime the carb starts right up

[FishHog]

It only starts in neutral.I have no throutle control.If I try to apply throutle ,the starter will stop as a safty thing.
What I do is move the throutle back & forth a few times as if pumping the throutle before starting.After around 10 times of doing so then it will finally start.I'm thinking all the gas drains back into the tank from setting for a long time.Is why I have dry starts.Seems the fuel pump takes for ever to pump the fuel as well.What I don't understand is,The gas in the float bowl is draining out as well?Is this possable?

There should be a switch at the bottom of your shifting lever (throttle only button), that you press so you can give it gas while still in neutral. I'm not sure from reading your post whether you realize that our not, but if not, that would be the first step. Mine is very hard to start at the neutral position, but with a little gas (like 1/4 throttle position), it fires right up.

[Don S]

It only starts in neutral.I have no throutle control.If I try to apply throutle ,the starter will stop as a safty thing.

Here are the procedures from an owners manual. From your discription, I think you need to give it some throttle while cranking. It sounds like you leave the throttle lever at idle while cranking.

4 Place control handle in NEUTRAL.

5 Push THROTTLE ONLY button and position throttle setting as follows:
COLD ENGINE - Move control/throttle lever to full throttle, then return to about 1/4 throttle. In extreme cold
it may be necessary to pump lever more than once.
WARM ENGINE - Move control/throttle lever to 1/4 throttle position.
FLOODED ENGINE - Move control/throttle lever to full throttle. Be prepared to decrease engine speed to
1000-1500 rpm as soon as engine starts.

6 Turn ignition key to START. Release key when engine starts and allow switch to return to RUN position.

7 Carbureted Engines - Move control/throttle lever back to decrease engine rpm to 1000-1500 rpm if necessary.

8 Check oil pressure gauge immediately after engine starts. If oil pressure is not within specified range (see
SPECIFICATIONS), stop engine immediately and determine cause.

9 If engine is cold, run engine for 1 or 2 minutes at fast idle (1000-1500 rpm).

[starwriter]

I am having many found problems with this boat.Speedometer not workng,Fuel gauge not working.Then,still we have the engine very hard to start after setting awhile.Sounds like a prime ball is what I need.
Hello,people.
I'm a old school motor head with older cars & engines.But,not a clue about Boats & engines.Seems my thinking is Boat engines & car engines should be the same/work the same as for these Mercruiser 4.3 apha 1's . I was told these are pontiac engines.I had a freind that installed one of these Mercruiser 4.3 apha 1's in a 1998 pontiac bonnaville.As for any carberated engines as a 2 or 4 barrols,most of the time you need to pump the gas pedal a few times to start them as old school.
I'm having fuel problems as not getting fuel to the carb fast enough while trying to start it?

I thank chris for his thought's but, a compression test isn't called for.You only do a compression test if you have a misfire or loss of power or smoking,blowing oil or checking for a cracked head or bad head gasget..I have none of those.This engine when running is fine.


As for the reply,
I think you need to give it some throttle while cranking. It sounds like you leave the throttle lever at idle while cranking.

My answer's yes I thought thats how you start it.Lol.I didn't know this throutle lever has that option for only throutle to engine without kicking in the blade.I'll look into it to see if this has that option or not.

I think this boat was setting for a few yrs before I bought it.When I first removed the anti siphon valve from the tank I found white dry currsion inside the anti siphon valve.Signs that it has been setting for awhile.

I'm gonna replace the anti siphon valve,Try taking apart the fuel pump to get to filter to clean it out.After doing all this if it don't help the starting problem.I'm leaning more towards the fuel pump is weak.Thinking of changing the fuel pump or converting it over to electric fuel pump.

[81 Checkmate]

What i think......

Need to pump shifter a couple times and then set it a 1/4 thottle and it should start. Just like old school as you say!

I think this is your problem...Also if you are going to add the inline filter do not use the plastic model.. get a metal one...Also could add a gauge to check fuel presure.

If indeed you need a new fuel pump by all means get a Marine rated pump.... Not an auto pump.... There are fire safety itens on them.