4.3l GM V6 random hard starting

[Svshaw82]

Hey guys, trying to narrow down a weird starting issue. So here is how our boat starts. In and out of the water, start on first 1/2 crank. Other times in water, have to crank it for at least 1 minute, several times. Sometimes on the water it will fire right up. It's all very random. It's more of a pita to start then we have fast starts.

At first I thought the fuel was siphoning back down to the tank, so I bought an in line check valve. That didn't solve anything.

Do you guys think I need to rebuild the carburetor? Or maybe just replace it? I don't know, because when it's running, she purrs and hauls butt. Making it tough to narrow down the hard starting. Thanks in advance!

 

[bruceb58]

Is it a problem when the engine is cold or warm. Do you advance the throttle while starting?

 

[Svshaw82]

Is it a problem when the engine is cold or warm. Do you advance the throttle while starting?

Doesn't matter, cold or warm. After running a while it will heat to 190, but the problem is the same. Like I said sometime (rarely) it fires right up. Cold or warm.

Can't really advance the throttle, that puts it in gear and it won't crank at all.

 

[Svshaw82]

I have tried throttling forward before starting to pump some fuel into the carb, that's never helped though. Only makes it stink of fuel after it finally fires up.

 

[bruceb58]

Can't really advance the throttle, that puts it in gear and it won't crank at all.

Yes you can. On some controls you pull the handle out and then advance and on some you push a button and you can move the throttle forward without it going into gear.

Once you figure how to do that, I think you will have a much easier time starting.

 

[Svshaw82]

Yes you can. On some controls you pull the handle out and then advance and on some you push a button and you can move the throttle forward without it going into gear.

Once you figure how to do that, I think you will have a much easier time starting.

How do I "pull the handle out"? There is only one button on it and it locks in neutral.

Not sure if this boat has that feature. It is a 1986 Cris Craft Tara.

Sorry for all the questions, we are new to boating. Thanks

 

[bruceb58]

Post a picture of your control.

You grab at the handle where it pivots and pull outwards...that is of course if there isn't a button at the pivot.

All controls have this feature. BTW, you should not be pushing the control into gear without the engine running.

 

[Svshaw82]

No Title

Post a picture of your control.

You grab at the handle where it pivots and pull outwards...that is of course if there isn't a button at the pivot.

All controls have this feature. BTW, you should not be pushing the control into gear without the engine running.

I've only done that to get it to pump fuel in, there really is no other way to advance the throttle. It only has trim and neutral buttons. I will try to attach a few pics now.

 

[bruceb58]

This is the type where you pull it toward the inside of the boat.

 

[lasko1]

I'm not familiar with your throttle, but my old OMC was just like bruceb58 explained....put your right hand on the inside of the throttle shaft (between the shaft and the padding on the boat wall, and pull the handle towards the center of the boat. If the handle pulls out (1/4" to 1/2" or so), then just push the throttle forward. This allows you to "pump the gas pedal" without the boat in gear. IF the handle does not pull out towards the center of the boat, it may be like my new throttle control. My throttle "button" is right at the pivot of the throttle handle which would be under the MORSE label on yours. See if you can push in on the MORSE label and then roll the throttle forward. There's gotta be something to let you rev the boat up without putting it in gear.

In regards to hard starting whether warm or cold engine....when my 1988 OMC 4.3 gets this way, a quick change of points, condenser, and rotor cures the problem.

Hope this helps and let us know the outcome.

Dave

 

[spoilsofwar]

Correct starting procedure for your engine is what these guys are telling you.

Place throttle control into neutral by pulling it away from gunnel, advance throttle fully to set choke and let the acellerator pump squirt some fuel into the carb (I give mine two pumps), place control at 1/4 to 1/3 throttle and crank engine. Should fire right up. Give it a second to settle, then select reverse gear and back off the trailer

Carbed engines get a bad rap as hard to start because either 1. They're in a poor state of tune/cleanliness, 2. People use the wrong starting procedure or none at all, or 3. Both. But I find a good condition carbed engine using the above process starts nearly as quick as a fuel injected one. JMHO

 

[Svshaw82]

Wow... I had no idea it did that. Yes it pulls out and rotates just as you guys described. Next time we have it out I will try it, thank you all for the advice!

I know it needs a good tune up. I hate doing points, has anyone ever upgraded to a Pertronics? I tried looking it up once, but I can't find a matching part number for this distributor.

Another thing, should I rebuild the carb too?

 

[bruceb58]

Just keep the points and change them annually. Buy a dwell meter and a timing light. Easy to do.

Pertronix are just not reliable enough. Case in point...look at the end of this thread:
http://forums.iboats.com/forum/boat-...tage-regulator

 

[Svshaw82]

Just keep the points and change them annually. Buy a dwell meter and a timing light. Easy to do.

Pertronix are just not reliable enough. Case in point...look at the end of this thread:
http://forums.iboats.com/forum/boat-...tage-regulator

Good read, I really do hate points. With my old muscles cars I've always gone MSD ignition.

So carb rebuild I think is in order.

 

[Svshaw82]

The throttle is difficult to move, are they rebuildable? It's not smooth, just hard to move forward and reverse.

 

[bruceb58]

Is it the control/cable or the carb? Remove the cable from the carb and try to isolate to one or the other.

Are you doing this with the handle pulled out so you are not engaging the gears?

 

[Svshaw82]

I think it's the control cable, it's just hard to put in and out of gear and throttle. Goes from part throttle to full l, and it's hard to ease in or out of the throttle, it's like the lever needs to be greased

 

[bruceb58]

I think it's the control cable, it's just hard to put in and out of gear and throttle. Goes from part throttle to full l, and it's hard to ease in or out of the throttle, it's like the lever needs to be greased

You are doing this while the engine is running right?

If so, disconnect the cable at the top of the engine to see if its the lower shift cable or the control cable.

I was actually having similar issues with my Mercury outboard, I replaced my whole console shifter with a GenII shifter and new cables and it works like a dream.

 

[Svshaw82]

You are doing this while the engine is running right?

If so, disconnect the cable at the top of the engine to see if its the lower shift cable or the control cable.

I was actually having similar issues with my Mercury outboard, I replaced my whole console shifter with a GenII shifter and new cables and it works like a dream.

Yes that's while running. I pull the button and push it forward, I hear it go into gear, and then push it over 1/2 before it starts to throttle, get harder to push as I go, until it just goes bam 1/2 throttle. Then if I go any futher it's harder to push then just goes bam full throttle. It still idles up, but I have to fight the handle to easy into speed. Like its sticky?

It hard to describe accurately. It will easy throttle if I tap the handle with my hand to make it go easy.

Maybe tomorrow I will try disconnecting the cables and see how it operates on its own.

 

[Svshaw82]

But it's also behaves the same when the engine is off. Sorry forgot to mention that.