Mercruiser 4.3 262 Magnum EFI Gen + Won't Start

[650]

I thought the same thing cause it happened after i filled it up but the gas i'm using to pour in is the same plus i have used a separate can to run off to rule it out totally

Sorry I haven't been to the boat yet to do the video

 

[650]

Hello again

Ok i have fitted the new ignition module and surprise no change ..checked all voltages and they're good
I have made a video but am having a little trouble uploading it ( will be up as soon as i figure it out ) shows fuel coming out of injectors which looks even from both but not starting then adding a little and if fires up then cuts soon as you stop

What i'm not getting is still that no matter how much i turn it over and the injectors are spiting fuel into the intake manifold the spark plugs are coming out dry
I took a plug out and where you should see a mist there was nothing i even put my finger over the hold felt the pull and push of compression but bone dry where could this fuel be going ?...
when i look down past the injectors the intake is wet with fuel it's as if it drys up before it make the 4 inch journey to the head

 

[alldodge]

If you wouldn't mind try this; take a small rag and stuff it down around the injectors. Crank the engine over some, then remove rag, move it away from the boat and put a match/lighter to it. Then tell us does it just burn or flash and burn

 

[650]

Ok i did the test on the fuel with the rag it was a windy day but it did light just couldn't tell if it was a flash it was a hot and sunny so made it hard to tell
But finally uploaded the video sorry it's sideways

https://www.youtube.com/watch?v=OqS7Ii12CYo

 

[alldodge]

Ok i did the test on the fuel with the rag it was a windy day but it did light just couldn't tell if it was a flash it was a hot and sunny so made it hard to tell
But finally uploaded the video sorry it's sideways

https://www.youtube.com/watch?v=OqS7Ii12CYo

From the vid that is plenty of fuel going down to run this engine, that is if it is good gas. I'm going to go back to the fuel quality and not the supply pressure. My suggestion is do one of two things;
Disconnect the fuel supply coming from the tank and hose a hose to a 5 gallon can. Drain the fuel filter and fill with fresh gas. Attach a hose to the can and try to crank enough to cycle all the old gas with new.

Either that or remove the VST, open the top and drain the gas out. Fill the VST back up with fresh gas along with the fuel filter and try it.

 

[650]

Ok i see you're thinking i'm sure i did this right at the beginning
I disconnect the feed right from the tank and used a can and turned it over for quite a while maybe not long enough to get rid of the old
But i will totally empty the filter and vst this time and get some 99 octane petrol

The thing i don't understand is the spark plugs are dry unless i pour a load of fuel into the manifold

I will be on it as soon as poss

Thanks again

 

[650]

Ok totally disconnected the feed from the boats tanks emptied both filter and VST filled with fresh fuel and still the same

Add a little and she with start to run then die

I have spoke to the last mercruiser mechanic that saw it and he is going to come back and plug it up see if we can get some codes out of it not sure if that will help but have to rule it out

 

[alldodge]

Your getting spark, Injectors are working and your getting fuel, just not enough. I no codes come back then I would be pulling the injectors and send them out for cleaning/testing. Cost about $25 each. Either that or replace them at much more, it's the only thing left.

 

[650]

Thats what i'll do hopefully we can pull the codes this week then go from there
I'll keep you posted thanks

 

[Fun Times]

Just watched the video, that's doesn't seem to be quite enough fuel being sprayed in my opinion. Chances are the scan tool isn't going to show any codes, it's going to be more if the guy using the tool knows how/understands the live date numbers if/once you are able to get it to run..... Have you tried opening the throttle from 1/4 to 100% while cranking? Try pumping the throttle like an old carb while cranking as a test.

You're fuel pressure should be 30 PSI. Since you have 38+ psi, that may indicate a restriction upstream of the fuel pump causing excessive pressure to the pump behind the restriction.

It could be a bad fuel regulator right at the throttle body or partially clogged fuel injectors and flow testing, cleaning/servicing may be needed like mentioned by AllDodge.

One other test you could try doing would be to disconnect the return fuel hose at the VST and carefully aim the hose into a portable fuel tank to see if there's a lot of fuel coming out of it and see if the engine will start.

Bear in mind that you have two fuel pumps that should need testing...The low psi pump, http://www.mercruiserparts.com/Show...sc=Fuel+Pump+And+Fuel+Filter(VST+Fuel+System)

Your complete parts catalog, http://www.mercruiserparts.com/selectSerailRange.asp?doc_nbr=262+MAG+(TBI)(GEN+)

 

[650]

Thanks Fun times
I was looking into getting a replacement kit for the injectors and regulator but being in the UK no one stocks them do you or Alldodge know anywhere that i could buy what i need i have seen some on ebay but they haven't got the regulator in with the kit

On the return at the VST when i was at the boat i didn't have it running but when i stopped cranking and undid the pipe there seemed to be a lot of pressure

and pumping the throttle seems to have no effect

Thanks All

 

[alldodge]

There are several places if you do a search on "fuel injector cleaning an testing". I add "in UK" and the first one came up with these
http://www.injectorcleaning.co.uk/contact.htm
Injector Cleaning
2 Crofters Drive
Cottingham
East Yorkshire
HU16 4SD
http://injectortune.co.uk/

 

[650]

No Title

Hello all

sorry it's been a week last sunday I was on the way to the boat and someone decided to lose control of his car coming round the corner and i happened to be coming the other way combined speed of 65 mph head on totaled both cars and lucky just to have concussion

Anyway back to the important stuff lol i've got down there this time and did the last test taking off the return pipe there was a steady dribble coming back but didn't start
I have taken the regulator apart and it looks ok but i know there could be a pin hole that i can't see ..

One other thing i did notice is when i was turning the engine over and pumping the throttle at one point the fuel out of the injectors stopped and i had to just open the throttle just a fraction more for it to start again ..(but not enough to start as normal )

I didn't know that i can get the injectors cleaned over here so i'll be on the phone to them in the morning to see if they can do these

Thanks

 

[Fun Times]

sorry it's been a week last sunday I was on the way to the boat and someone decided to lose control of his car coming round the corner and i happened to be coming the other way combined speed of 65 mph head on totaled both cars and lucky just to have concussion.

Oh wow, So good to hear that you're still with us all downstairs. Hope you feel better soon.

Anyway back to the important stuff lol

:thumb:

I've] got down there this time and did the last test taking off the return pipe there was a steady dribble coming back but didn't start

Don't know for sure but I would think there should be more than that. Wonder if your low fuel pump pressure is working properly.

I have taken the regulator apart and it looks ok but i know there could be a pin hole that i can't see ..

The other problem is new ones are hard to find/locate. So try asking the injector cleaners for info as well.

One other thing i did notice is when i was turning the engine over and pumping the throttle at one point the fuel out of the injectors stopped and i had to just open the throttle just a fraction more for it to start again ..(but not enough to start as normal )

That's normal. It's called clear flood mode. Some ECM's are set to turn off the injectors at 50% throttle, some 75 and some 100. Just depends as there is no real set number between all the ECM's available.

I didn't know that i can get the injectors cleaned over here so i'll be on the phone to them in the morning to see if they can do these. Thanks

Good job AllDodge.

 

[650]

ok i've been on the phone to the injector cleaners and as we were taking here asked me like you did about the return flow and i told him about the trickle

He also said that those single point injectors are normally pretty good

so if we are getting 38 psi in to the throttle body and a trickle out would it be the fault of the regulator and how would i fix this

should i get the adjustable after market model ?

 

[alldodge]

ok i've been on the phone to the injector cleaners and as we were taking here asked me like you did about the return flow and i told him about the trickle

He also said that those single point injectors are normally pretty good

so if we are getting 38 psi in to the throttle body and a trickle out would it be the fault of the regulator and how would i fix this

should i get the adjustable after market model ?

Not going to argue the issue with the fuel injector guy, just part of what he said doesn't add up to this non-expert. Hydraulics is hydraulics no matter where your at. "Pressure excreted on a fluid in a confined space, and acts with equal force on all areas". If a valve opens and the hole allows for a passage of fluid without a restriction, then a fluid will pass at a specific rate so long as the valve is open.

If you have 38psi at the throttle body line, and the vale opens for the correct amount of time, then the fluid passing will be the correct amount based on the design. An injector is designed to pass a specific amount of fluid based on pressure and the time the vale is opening. The only thing I can see that can reduce the amount of fluid passing, is the valve is not opening all the way, there is a restriction in the valve, or there is insufficient pressure.

Your pressure is sufficient, so I do not understand the injector persons his/her analogy

To answer your question, the regulator is part of the VST, and I know of no way to repair it.

 

[650]

No Title

PEOPLE WE HAVE A WINNER ....

I spoke to the injection guy again which sent me a diagram of the tbi working with the flow and showing the regulator ....when he explained how it should work i noticed something wasn't quite right mine wasn't set up like the diagram ...I had to go down to the boat for the 20th time and do the test and low and behold I couldn't believe it the injectors pushed out loads more fuel in a fan pattern and it fired right up

Ok what it was

You all said about about the flow return wasn't enough well thats what this guy said to ...when i said to him the flow is going into the regulator side of the tbi his said no the regulator should be on the return and that's where we started looking at the flow ...the nuts on the TBI are different sizes so can't be the wrong way round buttttt on the VST there the same and can be switched and that's what it was the flow was going into the TBI the wrong way
( the pictures are now i've swapped the pipes over the correct way )

Just to add this wasn't me the guy that i bought it off must have don't this just before i picked it up ....and don't worry he's getting the bill too

But thanks for all your help and i have a bit of the summer left to run it out in the English channel

Thanks all

 

[alldodge]

Pretty cool, sure glad you came back and filled us in. I'll stick this away and hope I can remember when and if needed again.
Many thanks

 

[Fun Times]

Were the two fuel lines switched at the VST or at the TBI?

And the return should have a lot of pressure at the VST correct?

And since you had 38 fuel pressure but should have 30, wonder if it came back to specifications at 30.

Thank you for all the updates till fixed.

 

[650]

Yes it was crossed at the VST ...and yes the pressure should be the same on the return like you said ...I haven't got the fitting to test the pressure again now...but i take it it's normal and i'm not touching it cause it's working .....It's our one sunny day over here in England today so i'm going to clean it and take it out of the harbour for a run with about 8 other boats that have seen me sitting at my birth day after day thinking i was just saving fuel and sitting on my boat ...I'll let you know how it runs

Thanks again Alldodge and funtimes