Hope someone can help here. This engine is actually in a Mastercraft boat.(The dealership is worthless) It?s a `99 5.7 liter with a throttle body. The engine turns over but wont fire. Plenty of fuel coming up but nothing getting into the engine. Engine runs fine if we squirt fuel into it. Any ideas of what to look for? Thanks, DZ
`99 5.7 wont fire
May 28, 2007
11 Replies
If the engine runs fine when you "squirt" fuel into it then...you are getting fire.
Fuel is the issue.
Check for an inline filter between engine and gas tank. Replace. If that dont do the trick, fuel pump would be next on my list. (you likely needed a new filter anyway)
When you say "plenty of fuel coming up" what exactly do you mean by that? Where is fuel showing up? Sometimes when a fuel pump goes bad it will still pump fuel, but not enough to maintain required pressure. If you have plenty of pressure at the TB then Id guess its something to do with the injectors. (probaly electronic) My money is on the fuel pump....
There should be about 14 PSI on line from pump and around 10 PSI at injectors after regulator
----------------- TheSnoMan.com
Fuel pump is working fine. Also checked the injector fuse and it's ok.
DZ
What is fine based on, noise from it running or fuel pressure test?
----------------- TheSnoMan.com
pressure test from line just before it goes into the base of the carb / t-body
a stuck 'closed' ( float in the up position ) float valve?
TBI units have floats and valves?
do they have carbs?
dzcamman
What type of distributor/ignition module does this thing have? Is it a Delco with a tall cap? and with two wires going into the distributer between the cap and base?
When you squirt fuel in does it run and stay running? or die after consuming the fuel?
skimmer
If you have adequate pressure at the TB, and you do not get fuel past the injectors, it has to be the injectors or whatever is telling the injectors to work.
I assume you have done a visual...no dirt daubers in the TB? Possibly a stopped up screen or passage in the TB?
If it has a good pump/filter/and pressure at factory specs...Im stymied.
Wish I could help more, but Im at my limit of knowledge, and dont mind admitting it! If its in a boat...Id be tempted to put a carb on it...
What pressure reading did you get? it should be about 14 PSI before regulator and around 10 PSI after regulaltor. ALso can you hear the TBI injectirs running?
----------------- TheSnoMan.com
Join the Discussion
Have something to add? Share your thoughts — no account required.
Didn't find your answer?
Ask the community — no account required