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4.3L Vortex stalls on big waves

akhinton

New member
Here's one for you, twice now, I was cruzing on step and had to throttle back for big wakes caused by the Alaska Ferry boats. As I throttled back (both times) the wakes rocked by boat (a bigger rocking that usual, these ferrys put out about a 4' wake) and my motor stalled out and refused to start. It appeared to be flooded but I am not sure about this. First time it happened I tinkered with the throttle, squirted a ton of gas down the carb and eventually got it started. Second time this happen, I could not get the motor restarted (even after squirting starter fluid down the carb) and had to use the kicker to get back to port.. The boat has been out of the water for two days now and I still can not get the darn thing started.

I pulled the spark plugs and they appear dry, not heavly coated (they were changed last year). Fuel is getting to the carb and appears to be vaporizing just fine. All spark plug wires are new and tight and the distributor was replaced last year.

The motor itself usually starts on the first turn of the key but is a bugger to warm up and I have to use alot of throttle (at about 1200 rpm) to keep it running until it is warmed up to 175 degrees... The motor runs very ruff during this time but once the temp hits 175 the motor calms down, it idles at 600 rpm without stalling out and for the rest of the day it will start up just fine. But once it gets cold, ...what a pain... Also, when it is cold started...lots of smoke,,,but the smoke goes away after a few minutes and It doesn't appear to be burning any oil...What could be wrong???
 
The carb is a Holly model 2300 two barrel. The motor is a GM 4.3L Vortex. I could not find a serial number on this motor which, having read several web sites about this motor, is not uncommon. By looking at the bolt pattern on the manifold, I've come to the conclusion that the motor year is a 1997/98. According to Seloc, the 1997/98 GM 4.3GL uses a Holley 2300 two barrel while the 4.3GS uses a Holley 4160 4 barrel. I don't know if my motor is a GL or a GS. I found a stamp on the case that says either GM 4.3LG (or perhaps L6) but I'm not sure what it means. I've considered putting a 4 barral on the motor to see what happens.

The Choke appears to work propertly, is particially closed when cold and opens as the motor warms up. The carb was replaced approximatley a year and a half ago. I had it tuned last September as I've always had a hard time starting the motor on this boat...even after the carburator was replaced. After the tuning, it was easier to start, but I still had to give it a ton of throttle before it warmed up propertly.

I have two fuel tanks on the boat, a 14 gallon aux and a 43 gallon main. Two weeks ago I completely used up the aux tank gas and used up the main tank gas to within 7 gallons remaining, so, the gas is about as new as I think I can get. I further have a fuel filter/water seperator to strain the gas which was replaced with a new filter last month. With new gas and a new filter, do you think the rest of the fuel system would really need to be cleaned out?

I pulled the plugs, they all look clean, they were also changed last year so I'm not surprised that they look okay. I'll check for spark and get back with you all on that. Thinking that perhaps the motor is still flooded with gas, I pulled all the plugs to let it air out over night.

What do you think the chances are that the float on the carb could use adjustment as perhaps it is allowing fuel to creep by the needle valve? Perhaps this could explain the wakes flooding the motor?
 
Pulled two different spark plug leads, hooked up a spaire spark plug to them and put the threads to a spot on the engine that I know is a good grounding point...no sparks... Now what?
 
Try a new Coil.

Coils do go bad, and will cause rough running, and then intermittent problems.

I had an ignition problem on my BBC, and it turned out to be the coil, and the used replacement I used was also bad. A new coil fixed it.

Bruce.
 
Thanks Bruce, I did some trouble shooting today and discovered a spring missing (and broken bracket) which connects to the fly weights located in my distributor. These fly weights manage spark advancement when the motor is at high RPMs as apposed to idle speed. I supposing that since a spring is missing from one of the two fly weights, that the distributor is advancing the spark prematurally which would explain why it idles so roughly when I first start it up....not sure that this explains why, after the motor is warm, that the idle is fine, but since the part is broken, I will replace it and see if it fixes the problem.

The guy I bought the boat from had the motor replaced prior to selling, but reinstalled all the old parts (ie, starter, distributor, exhaust manifolds, etc), Since purchasing this boat in 2008, I've been replacing all of these old parts in an attempt to get a good running motor out the whole deal, hopfully this distributor will be the part that fixes my problems...I'll look into coil prices too as the coil on the motor is obviously from the original engine. Thanks for your input.
 
........... I did some trouble shooting today and discovered a spring missing (and broken bracket) which connects to the fly weights located in my distributor. These fly weights manage spark advancement when the motor is at high RPMs as apposed to idle speed. I supposing that since a spring is missing from one of the two fly weights, that the distributor is advancing the spark prematurally which would explain why it idles so roughly when I first start it up.... not sure that this explains why, after the motor is warm, that the idle is fine, but since the part is broken, I will replace it and see if it fixes the problem.
To my knowledge, the Vortec 4.3L came on board during the last several years of OMC's run.
So my first question for you is; Is this actually an OMC stern drive system........... Or, is this Volvo Penta?
Second question is; what year model stern drive system is this?
If OMC, you will have an ESA system.... if Volvo Penta, you will not!
The ESA can play a roll in ignition sytem issues when not correctly adjusted.

As for the flyweight springs..... use extreme caution if replacing this spring (or springs) without the aid of a Distributor Machine.
As you said yourself, these springs control the amount and timing of Ignition Advance.... and this occurs once out of BASE mode/rpm.
IOW, I'd not hap-hazzardly replace these springs without double and triple checking your advance curve.
It doesn't take much (incorrect spring, for example) to throw this curve off, potentially resulting in engine damage.
If you know exactly what you are doing, this can be done "On-Engine".... but requires some additional techniques.

IMO, your engine does not require the HEI.
This will change your advancing system from Mechanical Advance (spark lead control) to EST (electronic spark timing... i.e., no mechanical advance).
If you are OK with that, then by all means give it a try.
However, trouble-shooting this system while on the water will be an entirely different ball game for you.
I'm just pointing this out to you as to better help you with a decision.

You also mentioned "wave" or "surge" when this occured.
By chance is your exhaust back flow prevention inadequate, malfunctioning, etc?

.
 
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Rick, you touched on what I've been thinking since this thread got started, surprised it wasn't brought up earlier as a possibility. The wake and resulting swell under the right conditions can cause water ingestion.
 
Woodie, that was the first thing that came to my mind also.... but the OP made no mention of Hydro-Loc or water wet spark plugs. Hmmmm.

.
 
listen motor running you ain't getting water up the exhaust from behind period.

1997 for sure? No esa.

Lets get back to the dist. It's fugazied want to take it to a track near you they will set it up for you.

Me thats got to come out and drop in a new unit, or your gonna be f--king around with this all summer and not be on the water.

No hei ok i understand that.

Me i squeeze a nickle till it turns into a dollar and then spend it on my kids.
 
Rick, The stern is a 1993 OMC Cobra--single prop--outdrive (model 987344). What is an ESA system? The distributor that I removed from my motor is a BID type distributor. the spring that was left was/is very rusty as is the bracket that it was attached too, The opposite bracket (to which the second spring would have been attached to) is broken. The broken piece, as well as the spring was missing from the distributor so somebody before me discovered the malfuntion and just removed the pieces and replaced the cap without fixing it. I found replacement springs online but cannot find the brackets (which are attached permanetly to the distriubtor shaft) Everywhere I've looked says "No longer available." After the holidays I was going to go looking in junk yards for an old 4.3L BID distributors as a possible replacement.

To be sure, I would pay the extra money for "easy and reliable" over "difficult and untrust worthy". So how difficult would it be to replace my BID distributor with an HEI unit. ...I couldn't find an HEI distributor in Seloc. What's involved?

As for back flow, in 2008 I discovered the motor was missing the port side exhaust check valve and yes, I injested water. I had a friend "tool" me a new check valve and I believe it is still funtioning property (as is the starboard exhaust check valve). I keep very close tabs on my oil level and have not seen any increase or decrease since the spring time oil change.
 
I'm fairly sure the motor is a `97. I couldn't find a serial number or model number but, judging by the bolt pattern on the intake manifold, and compairing it to a photo of a `97 in Seloc, it is the same, so my best guest-ee-mate is that it is a `97.
 
Here's an update. The springs came in for the distributor fly weights, one spring was the correct spring, the other spring that came was something completely different. I would have liked to change both springs to maintain symetrics but since I still had one spring it will have to do. I re-assembled the distributor and reintalled it too as close as possible to the position in which it came out. I further replaced the coil as the one on the motor looked old. ....Still no sparks

Checked my battery for 12 volts, battery checked good at 12 volts. Checked for 12 volts at the positive terminal on the coil using the negitive battery terminal to the positive coil terminal (with the battery switch on and ignition selected to run)--it read zero volts.

I ran a jumper wire from the positive battery terminal directly to the positive terminal on the coil.. Vo-la! the motor fired right up and idled like a champ! No having to mash the throttle forward to keep in running or anything, Almost seem timed just right. Problem is that I can't leave the motor like this (with the jumper wire attached) so will be shooting wires tomorrow to find the break. I ohm'd out the positive wire from the coil to the alternator and it appeared to be conductive. I further ohm'd from the alternator to the multi connector and it too showed conductivity. I will start tomorrow looking for 12 volts from the battery to the assist solinoid and then from the solinoid to the 50 amp breakers and then out back to the alternator and coil. Not sure what else to check from there...all the breakers appear to be in, all connections seem firm and tight and I couldn't find any broken or loose wires... will let you know how it goes. By the way, what the heck is an ESA module? I see it on the scematic but couldn't find anything about it in Seloc.. As the ESA module is somewhat wired to the coil I'm supposing there is a chance it is bad??? What does an ESA module do?
 
Should the motor still turn over if the deadman is pulled? I've got the deadman, it was never removed but perhaps hitting the waves caused it to swing enough to cause it to disengage? Don't know, ....I'm going to shoot some wires.
 
Motors fixed! dog gone it! that stupid deadman switch was off by a fraction of an inch! I don't know how many times I looked at that stupid thing but never put my hand on it. The clip, which is made of plastic is sun bleached and worn out. it was still attached but the plunger at the center of the switch was put out just enough to break the connection... Boy, glad I didn't go purchasing items just to change out...Oh, and replacing the sping on the fly weight of the distributor changed nothing...still hard to start and takes lots of throttle to keep it idling until it is warmed up, but once it is warm it runs swimmingly... Brother-in-law will be over next week, he's a mechanic (of sorts) and might know what to tinker with.. Later dudes.
 
hard starting ? Tell your brother in law to remove the fitting that enters the carb, there is a filter in there, and depending on the fuel pump might have a filter in there also.

Pull the fuel pickup tube and clean the screen, and blow thru the fitting see if the fitting is clear.

Me i crank the motor after pumping the throttle 2-3 times and leave the throttle down 1/3 of the way after no more then 4 revolutions i stop. Then i pump again leave it 1/3 of the way down. Crank the motor. If after 3 times doing it i stop. Take off the arrestor and dribble a few table spoons down the carb.

Crank the motor it should start mine does.. The choke should be closed.

Post back after your brother in law gets there and let us know what happens.

Latter gator
 
Fuel filter is/was good on the carb...

So I take the boat out today (First time its been in the water after reinstalling distributor with the new spring) Motor was a little sputtery while getting up on step but after the step it ran great--for about 15 mintues. Motor began to sputter so pulled the throttle back. Idle is fine, so I went to get on step again and it began to loose power at 2600 RPM. Adjusted the distributor a bit, got it up to 3000 rpm and it again sputtered and lost power. Twisted the distributor again. Could get up to 3600 RPM and again, loss of power. begain to idle back to port. Then motor began to loose power even at 2000 RPM. I shut the motor down and used the kicker to get back in..

I removed the new spring that was installed on the distributor fly weight. Motor idled fine, took it back out and it again was loosing power any where higher than 2600 RPM.. Took it back into port for more trouble shooting and twisting the distributor back and forther looking for a sweet spot, nothing, even when the motor was disengaged from the drive. I could bring the motor up to 3600 RPM and then the tach would begin jumping all around and the motor would start sputtering. I shut the motor off and when I went to restart it, ...it appears to be vapor locking. The starter went "Clunk!" and would not turn the motor... I drove home and attempted once more to turn the motor in my driveway...Again, a nasty clunk sound when the starter went to engage and you could hear the motor try to turn over but then stop, like it's stuck with a piece metal jamming something. When I took my hand off the starter, the motor sounded like it wanted turned backwards...

Man this motor is all screwed up. Checked the oil, same level as before...I don't think I injested any water... This engine has given me nothing but heart ache..

I want to yank this motor and throw it in the garbage... What would be a good, dependable motor and outdrive to replace it with... I'm done with OMC! ...Who makes a good motor for a 21' fully enclosed Bayliner Trophy?
 
MOtor is a 1996/97, installed in 2007 with little time (because its always broke). Drive is a cobra outdrive

As a side note, I followed chiefalen instructions on starting the motor. Normally, this motor is a bear to keep going when its cold. The carb was adjusted as well as the distrib last year but unless I give it lots of throttle, it wont idle until its warmed up. chiefalen said to give it three good throttle squirts before cranking. I did this. First time it worked great, no having to give it throttle or anything...started like it should. Second time I did this, it started fine but within 3 mintues of idle, the motor started dropping off and I had to go back to the original routine of giving it lots of throttle again until it was warm...
 
you have to leave the throttle 1/3 of the way down and crank the motor after the three pumps.

Let it warm up for at least 3 minutes time it on your watch no shortcuts.

You should be a little over 1200 rpm at 1/3 way down throttle.

The choke plate is open after 3 minutes if not then 4 minutes you time it with a watch and observe the choke plate then you will know when to pull back the throttle to neutral.

If it does not idle around 800 or keeps cutting out then you need a carb rebuild the idle circuit is clogged.

Now when you shift into gear on a warm motor you should be idling around 650 / 600 is better. Less is more when you shift so you can save your gears and dog.

I'm sorry for my long posts i want to teach and i think you want to learn i will set here typing with my two fingers as long as i think you want to learn.
 
Thanks chiefalen, it may be a while before another post as my motor is jammed and I will be talking with a mech tomorrow about my options.
 
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