350 Mag MPI engine Miss

[GodsBeast]

Well, I went out to check out a New Prop today. The wife took off Tomorrow, for my Birthday, and Monday for some boat ridding. Oh guess what. I ran the boat today and ran about 15 gallons of gas through it. Docked to refuel. Filled the tank. Started Engine, and backed out. Put into Forward, and had a Vibration. Killed Engine and found a Stick in the Prop, lodged next to the Prop Nut. Pulled the Stick out! Started Engine and it had a terrible Miss. The only hose I found loose, looks like a wire loom hose, which goes to the PCV valve looking thing on the Port side Valve Cover. I looked all up under the Air Cleaner could not see where it hooks up! Anyway, I would not think this would make the boat run this bad. Could not get it above 3000 RPM's Ran all the way back to the dock. After docking and backing the truck into load, the boat would not start. Took a long time for it to finally start and it had no power! <br /><br />Is there any quick things I could check out, that may have come unplugged or something. The Wife is dissapointed that she took off work for nothing. I also took off work this weekend. This has to be something simple. It sounds like it is not getting enough fuel, or Air Mixture!<br /><br />This is a 5.7 350 MAG MPI, 2003 model. <br /><br />I would appreciate any suggestions, please be discriptive, I am not a good Mechanic! Thanks for any help in ADVANCE!<br /><br />GodsBeast

 

[rodbolt]

Re: 350 Mag MPI engine Miss

Hello<br /> pull the fuel water seperator off. this is a canister that looks like an oil filter mounted on the front starboard side of the engine. if it has water then replace it and fill the new filter with fresh gas before reinstalling it. sounds like a water problem . fuel injection does notr rely on engine vacume to move fuel like carbs did. if the filter is clean then check for the coil secondary wire arcing to the coil primary terminal.<br />good luck and keep posting

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Thanks for the quick Reply Rodbolt, when you say replace, you mean put the same one back on with new fuel, or replace with a new one and new fuel. <br /><br />What does the secondary Coil wire look like, I have a friend coming later (if he can) he is a mechanic, but has not worked on boats. Any tips on what color wire. or its location, so I can check to see if it is arching before he comes IF HE Can come?<br /><br />Thanks again. Rodbolt.

 

[johnkc]

Re: 350 Mag MPI engine Miss

are you not getting any beeps from the warning horn?if you can't get over 3000 rpm it sounds like it is in power reduction.caused by a fault of some sort. also is it an alpha or bravo drive?

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

John, I'll have to admit, I didn't hear a warning horn, but I am hard of hearing, I try with the muffs, and pay special attention.<br /><br />I have an Alpha One drive.

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Hey guys, in going though my Manuel, it says, flame arrester, possibly dirty. What is, and where is the flame arrester? Trying to locate it, to check.

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Finally found the Flame arrestor, why didn't they just say Air Filter Container. OK off to check that now.

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Took Flame arrestor off, could see through filter, looks clean, Engine looks clean, bearly drove through 150 feet of gravel to launch pad, every two weeks, so with less than 70 hours on the engine, and boat, figured it would be clean. Found a screw on cap hooked to the Fuel injection, unscrewed it. Seen what looked like a tire needle valve. Pushed valve, gas came out, I held my hand over it, I figured it would shoot out, but it just poured out around the needle valve. Anyone know what the fuel pressure should be, when hooking a fuel pressure guage on it? <br /><br />Engine will not start with muffs hooked to it now! Any suggestions, other than take to dealer? <br /><br />With Flame arrestor off, still was unable to see where the wire loom looking tube from the PCV valve was suposed to hook too near flame arrestor.

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Rodbolt, I didn't want to take fuel water seperator (Fuel filter) off tonight because I don't have a new one to put on! Can these be taken off drained and used again? Or is this a NO NO? I also have approximatly 20 gallons of gas left in the tank. Would have to go to Wally World tomorrow to get more gas cans to drain this fuel into. Any other suggestions?

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

I guess that is out too, I was going to take the filter off, and try to remount it, and buy another one tomorrow if it worked, but the (&*^* thing feels like someone screwed it on with an impact wrench! They have it mounted to an Aluminum bracket, and I was scared I was going to break the bracket getting it off! I even put a filter wrench on it. <br /><br />I know lefty loosey, Righty tighty. I can change oil, but this is rediculas for a fuel filter.

 

[loadnet]

Re: 350 Mag MPI engine Miss

GodsBeast...<br /><br />Ya need to go back to the begining..<br /><br />

The only hose I found loose, looks like a wire loom hose, which goes to the PCV valve looking thing on the Port side Valve Cover. I looked all up under the Air Cleaner could not see where it hooks up! Anyway, I would not think this would make the boat run this bad.

You say you started her up and found a stick stuck in your prop blade.<br /><br />After removing the stick your engine fired but was mis-firing correct?<br /><br />It sounds to me like your engine actually ran backwards (coughed) for a split second when it choked on the stick stuck in the prop.<br /><br />When an engine backfires or runs opposite of it's normal rotation as in backwards (even for a split second) it can blow vacuum lines off the engine instantly, because compression sneaks by the valves and ends up in areas where compression is NOT supposed to be, such as under your intake manifold.<br /><br />Now - You say you have a line from your PCV that is NOT connected at the other end.<br /><br />Comb the engine intake manifold and throttle body housing and see if you can find a metal or plastic tube sticking out somewhere with NO hose attached to it.<br /><br />That is probably where your PCV hose should attach.<br /><br />If after finding the vacum tube you re-attach the hose and your engine STILL does not start - yank the spark plugs and check em out.<br /><br />Chances are they got washed out with gas when you were attempting to start the engine with no vacum present.<br /><br />Vacum leaks such as the one I suspect you have now, can cause tons of running problems including a major skip in the engine.<br /><br />Look on the backside of the throttle body housing for the little metal tube to connect the PCV hose.<br /><br />Let us know how you make out.

 

[tylerin]

Re: 350 Mag MPI engine Miss

Godsbeast,Agree with other post to start at the beginning. You filled up w/ gas and it started running funny, you pulled stick out of prop. I would check prop area for any furthur obstruction. Replace fuel seperator. I know you know righty tighty lefty loosey but the filter is mounted up, is it possible your going the wrong way? On a previous post you were looking to rev motor in nuetral and were playing w/ the shift lever did you by chance mess w/ the kill switch? Check ant-syphon valve. Your manual should give you the fuel pressure. Does the motor turn over? When you said you put it in gear the motor had a vibration, this could be from a electronic shift assist which momentarily interrupts the spark to allow you to shift into gear easily. Just a few thoughts. I agree w/ CaptHooknfinger go back to where it all began and what you have done since for starters

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Guys, I got the fuel filter off, dumped it, did not see evidence of water in the fuel.<br /><br />What next?

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Filled it with fresh fuel, screwed it back on by hand. Hooked to water hose, it will not start. Just turns over, and hits once or twice now and then but won't start. The filter is not leaking, was just trying to get it running, plan to change filter before ever going out again.

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Captain Hooknfinger, The hose from the PCV valve is hooked up. The wire loom hose from the other valve intake, with a wire loom type hose, is not hooked up. It has been explained that this hose is a vent type hose, and just clips under the Spark Arrestor. All hoses looks like they are hooked up. I believe this thing is going to have to be hooked up to the diagnostic meter. Problem is, they can not get to it today. The dealer that I bought it from is a 7 hour pull, they would work overtime if I brought it in, and would love to check it out. <br /> I am just not up to a weekend off, spent in Alabama, checking this thing out. So I guess I am just stuck with the weekend off, trying to be pleasent when folks call to wish me a Happy Birthday!<br /><br />I appreciate yall trying to help. Will welcome any other ideas.

 

[navigator336]

Re: 350 Mag MPI engine Miss

I'd hate to see you miss a good weekend. As the problem started virtually right after getting gas, is it possible you got a bad load? I can't imagine a stick stuck in the prop hub area could have created enough back pressure to cause any engine problems. The vibration for sure but not anything more severe. If your engine was carbureted, it would be easier to check for bad fuel. Did you check the coil as one person suggested? It's pretty easy to check the coil and distributor output by pulling the plug wires off one at a time and sticking a phillips head screwdriver in the cable. Then bring the shaft of the screwdriver very close to the block or head (make sure you hold the screwdriver by the handle) and have someone crank the motor. You should see a spark jump from the screwdriver to the block or head. Try it on all the plugs. If you get no or inconsistent output, it could well be a bad coil. If you have an HEI ignition system, which you probably do, parts will be available a any chain auto parts store.

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Thanks Navigator, when I get someone else around, I might could try that. I have been having some problems with fluxuating RPM's with trying out different Props, we have suspected that something was not diagnosticly set right all along. I might give that a try, but plan to take it in first thing Monday Morning to get it in line to get it diagnosticly checked and set right, otherwise I will be worried about it from now on! <br /><br />I also agree on the stick in the prop, it was very light, old wooden stick, it was only a few inches long, and just the right diameter, shaved off to get stuck between the prop nut and the housing of the Prop. The engine was running bad right off after, cooling off, and refueling. I have taken the filter off, emptied it and the tank is clear,(see through) and the gas looks a consistant color, even with one side of the trailer jacked up, hoping to see something in the tank. It all looks good. <br /><br />I'm just thankful that it started and got my Dad back to the Dock (he is a Heart Patient) with other Medical Problems also.<br /><br />I appreciate everyone that tried to help.

 

[johnkc]

Re: 350 Mag MPI engine Miss

the fuel pressure is 38 to 43 psi engine running or if you want,just turn the key on and the pump will cycle and will give at least 38 if all is good.we had a bulletin on some problems with the HVS commomly known as the distributer.they get water under the cap .so pop the cap off the dist and check it out.good luck.

 

[rodbolt]

Re: 350 Mag MPI engine Miss

you say you took what looked like a tire valve cap off and depressed the valve? that was the test port for the high pressure fuel rail. it should have sprayed all over you. the MPI engines run about 35 psi in the rail. when you cycle the key switch to ON can you hear a high pitched whine for about 5 seconds indicating the high pressure pump is pressurizing the system ?<br /> a standard automobile test gauge for TBI and MPI will work to test fuel pressure. I think you can rent them from auto parts stores. just remember you are working with gasoline in a enclosed area. be very careful and no one smokes keep the blower on and the spills wiped up <br /> good luck and post again

 

[GodsBeast]

Re: 350 Mag MPI engine Miss

Hey John and Rodbolt, I will check under the distributer for moisture. <br /><br />Also Rod, the Odyssey Dealer, also told me that I had indeed found the port to check the fuel pressure. He also told me it should check between 43 and 46 lbs at idle. Another reason he has suspected low fuel pressure, earlier, when I was complaining that I was not getting the speed they said I would out of this boat, and a 17 Pitch S.S. Blade was not getting into the RPM Range. He began to suspect other problems, before now, and over the phone was giving me the simple fix solutions fist and going down the list, but strongly suspected low fuel pressure, or another Computer related problem.<br /><br />I also heard the wine yall spoke of when turning the key. I have some hearing problems, but heard two different tones. I have checked all fluid levels and things, I can check, without the computer, that I know of.<br /><br />John I'll pop the cap early tomorrow morning, just had enough looking at it today, and had to walk away for a while. I had a Weedeater once that kept giving me trouble, and I wrapped it around a telephone pole, it does not give me any problems anymore! But somehow this is just too much money for me to loose my cool with, so I thought it best to walk away. <br /><br />I'll check the board, later and first thing when I get up, If anybody else has any suggestions to try in the morning, I'm always willing to learn.<br /><br />Thanks folks,