Cant get mercruiser 4.3 in time!!!!!!!

Alpheus

Lieutenant Commander
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Re: Cant get mercruiser 4.3 in time!!!!!!!

Do you need to pull the distributor and rotate one tooth to get the adjustment needed?

That will do absolutely nothing. ^^^


Read the manual and do the procedure for installing your distributer with engine disturbed method. Maybe the previous owner messed it up. Just start from scratch and then you will know its right..
 
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Re: Cant get mercruiser 4.3 in time!!!!!!!

That will do absolutely nothing. ^^^


Read the manual and do the procedure for installing your distributer with engine disturbed method. Maybe the previous owner messed it up. Just start from scratch and then you will know its right..

I have verified that the dist is where it needs to be mechanical timing is good. what about the optic sensor in the dist what if that is bad? or a week coil??? I can set the timing to the 8 deg like it is supposed to be but the engine will not start. if i back it off more it will run but run like garbage



i have heard that the higher the compression the hotter spark is needed if the engine will run at 14 deg before tdc (piston hasnt compressed the air fuel mixture completly) but wont run at 8 deg btdc full compression. in theory if it was a week coil sending a week spark it might not be enough spark to ignite the air fuel mixture at full compression...... could it be the coil week?
 

dubs283

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Re: Cant get mercruiser 4.3 in time!!!!!!!

if the ignition sensor is bad there would be no spark, 99% of the time they either work or they don't

it could be a weak coil causing weak spark, try testing spark with a spark tester from the coil tower to a good ground

based on your posts, there is no timing grid?? just a notch and groove in the balancer??

if so, you will need an advance timing light to properly set timing, don't rely on someone's mark on the balancer
 
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Re: Cant get mercruiser 4.3 in time!!!!!!!

if the ignition sensor is bad there would be no spark, 99% of the time they either work or they don't

it could be a weak coil causing weak spark, try testing spark with a spark tester from the coil tower to a good ground

based on your posts, there is no timing grid?? just a notch and groove in the balancer??

if so, you will need an advance timing light to properly set timing, don't rely on someone's mark on the balancer

Yes just a v notch and the 0 degree mark from the factory and someone else made a grove where 8 deg would be but the engine will not run anywhere near the 0 deg mark or the 8 deg mark they made the only way I can get it to start if its about 6 inches to the left of the 0 deg mark and it runs like crap

tomorrow I am going to exchange my coil its under warrenty still as for timing the engine I only have a standard snap on timing light
 

dubs283

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Re: Cant get mercruiser 4.3 in time!!!!!!!

so when the light flashes, it shows the groove approx 6" to the left of the notch??

something isn't right - at the most on #1 the groove should only be an inch or so from the notch to run - no way would the engine run, poorly or otherwise, with the groove 6 inches from the notch on #1 (that would be like 90 degrees advanced)

do you have the manual??
 

Alpheus

Lieutenant Commander
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Re: Cant get mercruiser 4.3 in time!!!!!!!

Your not listening. Weak spark has nothing to do with your timing not lining up. Hot spark is needed for high performance,high compression engines. Not a 4.3 truck engine. You came on here looking for advise and you didnt listen to any of it. You go on and enjoy throwing more money at it and it will not fix the underlying problem.

Im out...
 

Bt Doctur

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Re: Cant get mercruiser 4.3 in time!!!!!!!

Did you bother to look at the link in post #4
 
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Re: Cant get mercruiser 4.3 in time!!!!!!!

so when the light flashes, it shows the groove approx 6" to the left of the notch??

something isn't right - at the most on #1 the groove should only be an inch or so from the notch to run - no way would the engine run, poorly or otherwise, with the groove 6 inches from the notch on #1 (that would be like 90 degrees advanced)

do you have the manual??


I have the mercruiser service manual number 14 and 18 for my boat
 
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Re: Cant get mercruiser 4.3 in time!!!!!!!

I am listening to everyone Its just I have gone over and over the correct timing procedures unless im missing somthing. I have put number one at tdc on compression stroke verified that the rotor is pointing to where the number one wire should be. there is somthing weird going on with my ignition not sure but all the steps everyone has pointed out I have done I am trying to explain the best I can hang on brb to read post # 4 too much going on lol
 

Bt Doctur

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Re: Cant get mercruiser 4.3 in time!!!!!!!

worst case someone installed the dist incorrectly and #1 on the cap is NOT #1 cylinder.
can be verified with the hose end from a compression tester. remove #1 plug a listen/feel for the pulse of air while looking at the rotor position.where the rotor points ,call that #1 wire and install the other plug wires in the correct firing order.
whatr ign system is installed? TB IV or TBV
 
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Re: Cant get mercruiser 4.3 in time!!!!!!!

worst case someone installed the dist incorrectly and #1 on the cap is NOT #1 cylinder.
can be verified with the hose end from a compression tester. remove #1 plug a listen/feel for the pulse of air while looking at the rotor position.where the rotor points ,call that #1 wire and install the other plug wires in the correct firing order.

I was just compairing the old dist cap with the new one. It seems that the 4 bolt pattern compaired to where number one is on the dist cap is a bit different between the old and new would that make a difference?

I had checked that and with the compression stroke on number one the rotor button was pointing to where number one would be on the dist cap and that is what confuses me prior to me having any issue my motor ran 8 deg perfectly I never pulled the dist off a tooth. i am trying really hard to explain I plan on checking it again tomorrow (rainy and dark right now lol) but Im almost positive that the dist rotor was where it should point on the dist cap.
 

Bt Doctur

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Re: Cant get mercruiser 4.3 in time!!!!!!!

the cap is notched ,can only be installed one way.I have to assume it did at one point run correctly. review your work.
 
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Re: Cant get mercruiser 4.3 in time!!!!!!!

OK soo things to check tomorrow I am going to check to make sure

plug wires are correct on dist cap to corisponding cylinder in a clockwise order 1-6-5-4-3-2
going to make sure number one cylinder is tdc on compression stroke and rotor button is at number one on dist cap if not correct it.

going to check harmonic balancer to make sure its not sliping or moving

do i need to check for anything else? I know im forgetting somthing but i am going to do all these checks again and let you guys know.
 
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Re: Cant get mercruiser 4.3 in time!!!!!!!

When you recently had an issue with it not starting, would it just up and not start? period? So then you replaced the cap, rotor, wires, plugs, replaced all the fuel lines, fuel pump and rebuilt the carb just because? Does it have a fuel water separator? Was it replaced? Then it still wouldnt start till you replaced the oil pressure sensor but it was out of time so THEN you set it to 8degrees? What was it set on before?

You need to make 100% sure that you have those wires on correctly. Nothing wrong with the timing light? How did you verify piston 1 is TDC with the rotor pointing to wire #1?

I hope my timing light works lol it was originally set to 8 deg but i screwed it up by accident. the not starting issue wasnt why i was timing i was timing to make sure it was good and by accident moved the dist
 

Jeepster04

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Jan 5, 2009
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Re: Cant get mercruiser 4.3 in time!!!!!!!

So everything was working great till you slipped and moved the distributor on accident?? Thats insane. Not sure what else to say that hasn't already been said. Just go over everything and double check everything.
 
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Re: Cant get mercruiser 4.3 in time!!!!!!!

ok I am gonna try to start from the begining all the events that led up to now. First I had an issue with what I thought was my coil my engine would die and stall and backfire. I replaced the coil because it was leaking the cooling oil out the seam. I found that I had a hose leaking water and spraying water right on to the dist and causing the spark to jump and track all over. fixed the leaking hose. worked good then a new issue started up a few weeks later. The engine would run perfect for about 30 mins then anything after half throttle to wot the engine would hesitate and loose power If i shut down for a while and start up it would run fine for a bit then again do the same thing I checked the entire fuel system thinking it was starving for fuel rebuilt the carb checked all fuel lines (it was also hard to start always has been) when trying to figure out what it was I got tired of a bad battery and got a new one took it out to the lake to test more and it stoped doing it atleast for the short while i ran it. while out on the lake after the new battery it seemed not to do it but my engine seemed to run out of fuel died and wouldnt start up paddled back and put fuel in the boat. It would not start. this is what led me up to replace the dist cap the rotor spark plug wires and spark plugs. motor still wouldnt start. This is where I accidently moved the dist when I was checking time to see if it was good timing was at 8 degrees but I accidently moved it out of time. I was still not getting enough spark. somone told me to jump the coil to the battery and this is where i got the motor to start up wouldnt run good at all no matter where i adjusted the dist cap to. then I lost fuel my pump stoped working or getting power. this is where I figured out my oil pressure switch was not working. I replaced the oil pressure switch and motor started up without the jumper to the coil. but still run horrible no matter what the timing was set to. wouldnt start when set to 8 degrees. but increase it so the timing mark is further left when the timing light lights up it started. ran horrible but started now this is where I am now trying to figure out why i cant get the motor to run at 8 degrees when I have never pulled the dist off the gear. prior to any of this the motor ran great 55 mph across the water. so maybe this will help everyone understand my issue I could be mistaken but i am pritty sure that when number one is at tdc on comression that the rotor is pointing to number one on the dist cap going to recheck tomorrow
 

pwpns

Seaman
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Jun 25, 2010
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Re: Cant get mercruiser 4.3 in time!!!!!!!

ussoldier1984 try checking to see if your harmonic balancer hasn't moved. You can check this by removing the number one plug and putting a small dowel through the plug hole and rotating the engine by hand to find its uppermost movement (you can feel the rod go up then start down) and your 0 mark should be on the pointer. The other mark (the one 6" to the left)on the balancer is a mark that puts the entire cam on base circle so the factory can set the valve lash without having to move the crank. You also might have a timing chain set that is getting loose and causing you to have erratic timing issues (the hotter it gets the more it strecthes). You might want to check this before it jumps a tooth and does serious damage
 

EddiePetty

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Re: Cant get mercruiser 4.3 in time!!!!!!!

.... You also might have a timing chain set that is getting loose and causing you to have erratic timing issues.....

pwpns touches on a good point!!! Let's eliminate one more possibility for your erraric timing.

With the plugs removed and the distributor cap off, hand bar the engine over until the timing marks align. Watching the distributor rotor, hand bar the engine in the opposite direction until the rotor begins to move..STOP. The distance (viewed on the dampner) from your original aligned marks to the stopped location is the degree of slack in your timing set.
 

muc

"Retired" Association of Marine Technicians...
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Re: Cant get mercruiser 4.3 in time!!!!!!!

Hi,
How many fingers are on the metal wheel that is attached to the new rotor in the distributor?
Good Luck Muc
 

gbeltran

Petty Officer 1st Class
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Re: Cant get mercruiser 4.3 in time!!!!!!!

How are you verifying that the number 1 cylinder is at tdc?
 
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