454 MAG. BRAVO MPI (GEN VI) GM 454 V-8 1997 Crank No Spark

[alldodge]

Hope your up in running soon

 

[JimmyD150155]

Been a while had to take a break from the engine, now back at it. I have now a spark now after replacing the pickup coil in the distributor and solved a fuel supply issue noticed last week.

I can crank and get a spark now yippee. I cranked five or six times for 20 sec or so and the following noticed:

1. Petrol getting up to vapor tank and past electric booster pump
2. Spark strong at all plugs
3.NO FUEL IN CYLENDERS AFTER REMOVING SPARK PLUGS
4. I am guessing fuel injector problem.?
5. There was a puff of smoke briefly from the air intake box and a slight kick again for an instant.

Advice would be good on what now, what is the procedure to remove the fuel injectors to clean or check.??

Thanks almost there I think.

Jim D

 

[alldodge]

Do you see the tach going up to around 300 rpm while cranking as FT mentioned?

When the key is turned to ON, do you hear the VST pump turn ON for a couple seconds?

Attach a pressure gauge on the fuel rail to see what pressure you have

If pressure is up, tach is showing 300 rpm, then need a Noid light to place on injector contacts to see if they are getting a signal to fire

 

[JimmyD150155]

Hi Al

The rev is about 300 and shaky I guess ok at that

The VST pump does startup but I opened up to look at it as like all parts its been a while since they were used, I was shocked and my heart sank, the filter at the bottom was almost completely caked (pic attached).

I cleaned it up and tested the pump separately and it still pumps thank goodness.While the VST was open I tested the float valve, the tank was full so mechanical pump which I replaced is working,

I tested the engine again convinced that was the problem but no kick and only an occasional backfire after trying for what must have been 5 mins on and off. Took plugs out but only one looked any sign of fuel.

I will buy try and buy a pressure gauge tomorrow and check fuel pressure on the rail valve. I did press the valve at the end of the rail and fuel spurted out about 3 or 4 inckes so not extremely high pressure, what should it be.?

Quick question with the Plenum removed is it ok to crank to check the 12v to the injectors as suggested.?

Thanks again

Jim D

 

[Scott Danforth]

Getting back to your thread here.

your boat had rolled in a storm and everything electrical was submerged in salt water, and even your steering cable needed to be replaced per post #11 - correct. this was 18 months ago, and now you are seeing the issue.

salt water will have wicked up all your battery cables - replace them
salt water will have wicked up all your harness leads - replace them

you already found what salt water did to your dizzy.

you have also found what salt water did to your fuel system

normally when a boat gets submerged in salt, here is what is done immediately to save it:
remove drive
remove motor from boat
change engine fluids
replace rotating electrics
replace wiring harnesses
replace battery cables
replace electronics
get motor running within 24 hours (usually done on a stand or pallet to get it going while out of the boat)
drain fuel system
new batteries
new steering cable, and sometimes a new helm
new control cables
purge and re-fill power steering lines
purge and re-fill tilt/trim hydraulics
reinstall engine
new gimbal bearing
new bellows
check alignment
install drive
change drive fluids

at least down here that is what is done to it

if the boat is submerged for more than 3 days, the motor and drive are usually replaced, and in many cases the insurance companies will total the boat.

based on the pictures, i am willing to bet you find more systems that will have been affected by the salt water

 

[alldodge]

Quick question with the Plenum removed is it ok to crank to check the 12v to the injectors as suggested.?

Pressure should be 43 psi, and its ok to check with plenum off but everything electrical needs to be connected. You only need to check of couple of the injector connections. If the few are showing there working the rest are, they are batch fired. Look at the wire colors and try to check the 2 different colors

 

[JimmyD150155]

Hi been a while since I could get back working on my engine problem but did over the last few days. I got the pressure gauge and attached to the end of the fuel rail, on ignition on i can hear the booster pump and pressure gauge jumps full reading (100psi) and drops on cranking to pulse about the 45 psi mark. Guess fuel is in the rail at the correct pressure.
My next assumption is that as I can confirm good spark in all cylinders but no fuel in cylinders (after spark plug removal) is that the injectors are not functioning.
I am going to check again that the 12v is getting to the connectors, any other ideas that might help would be appreciated.
Regards

 

[alldodge]

You will need a noid light to check injectors, it happens real fast and needs a low impedance connection

 

[JimmyD150155]

Thank you AllDodge I just found a source for them here in the Philippines.

 

[QBhoy]

Did you bleed the fuel rail at the test point ?