Hi Everyone,
I'll start with a little history - Engine is a 2005 Volvo 5.7 MPI Gi-E. The boat has always started right up with a turn of the key. This season I started experiencing intermittent hard starts. Sometimes it would fire up with a turn of the key, other times I had to put the shifter in neutral and give it a little throttle to start.
I replaced the plugs, wires, fuel filter, rotor, and distributor cap. Seemed to fix my problem - started getting easy starts back at the marina. However, I would get the same issue after being at anchor or stopping at the fuel dock. I would have to pop the shifter in neutral and give it a little throttle to start. Also started to notice some popping at around 3,000 rpms while on plane.
Next time out the engine started with a turn of the key at the dock. Went directly to fuel dock, had to give it throttle to get it to start after fueling up. Ran fine (maybe a miss here or there) for the 20 minute ride to where we anchored (a mix of no wake zones and regular zones). Anchored out for about 2-3 hours and when we were ready to go I had to give it throttle to get it started. Tried to get up on plane but it was running very rough and sputtered. Turned it off and tried to re-start the engine. This time could not get engine to turn over even by giving it throttle. Had to get a tow back to the marina.
Following day did some additional digging. Upon further inspection my flame arrestor was very, very dirty. I could hardly blow air through it. I cleaned it with brake cleaner and a strong hose and got it back to brand new. Also checked my plugs (recently replaced) they were dirty and wet, so I decided to replace them again and use the ones I replaced as a back up for next tune up since I know they are still good. Lastly I replaced the IAC valve.
Tried to start it and just wouldn't turn over. Kept trying. After about 10-15 tries it started to try to turn over. It would dieseling slightly when I stopped cranking so I popped it in neutral and gave a little throttle and finally got it started. This is on the work rack on a water hose. Once i got it started I put it in neutral and gave it some throttle. Initially was a little rough but it ran smooth after a minute or so. It was noticeably smoother than before. Had to wait until next day to put it in the water and test drive.
The next day got it in the water, again took a few tries to turn over. Once started it ran smooth, real smooth. No popping or hesitation, got to WOT of about 4800 rpms and about 53 mph. Never ran better.
The next day I get to marina and it took about 15 tries to get it started. would crank and crank and when I turned key off it would sputter a little. Got it started by shifting to neutral during that stutter and giving it a little throttle. Once warmed up I shut it off and am able to start "right" back up rather easily. However, went to the gas dock, put some fuel in and took a couple of tries again to start it after fueling up. Once started ran perfect again. WOT and top speed reached easily. No hesitation.
Next time at the marina I put it on a work rack and checked the fuel pressure (thank God for youtube and auto zone tool lending program). The fuel pressure checked out fine. Low Pressure was 12 psi and the high pressure pump was at 50psi, both within spec. Removed the fuel pressure regulator , inspected it - a very little amount of debris/dust on the screen. I cleaned it up with carb cleaner and reinstalled. No issues with the oil either.
Boat will not start at all now. Checked with marina mechanic to see if they could take a look. They told me it would take three weeks to check it out. Did some searches on the forums. Saw that someone had a similar issue and it was the coil. So I decided to change the coil. The boat fires right up. I turn it off an on multiple times...fires up each time with a turn of the key. I'm on the rack so can't test on the water for a few days.
Yesterday I get the boat in the water - fires right up. Head to the gas dock, get some fuel, fires right up again. Runs perfectly on plane - I anchor out. Turn the boat off. I turn it back on and it fires up but I sense not as quickly as before. After a couple more tries I have to give it some throttle to start up. It starts right up with throttle. Go back to the marina. Put it back on a work rack and it turns over with key.
What am I missing?
1. Anti-siphon valve? I tried to replace the anti-siphon valve but its in a difficult place to get any leverage on the nut and it seems to have some type of sealant or cement on the threads. Any tips on removing the sealant? Maybe the valve is not functioning properly after the fuel tank gets stirred up?
2. Fuel injectors? Would the boat run great once started if the fuel injectors were the issue?
3. Any other ideas? Other things I should check? I think I maxed out my mechanical ability.
The two things that I know were wrong and resolved were the coil and the dirty flame arrestor.
Thanks in advance for any help.
I'll start with a little history - Engine is a 2005 Volvo 5.7 MPI Gi-E. The boat has always started right up with a turn of the key. This season I started experiencing intermittent hard starts. Sometimes it would fire up with a turn of the key, other times I had to put the shifter in neutral and give it a little throttle to start.
I replaced the plugs, wires, fuel filter, rotor, and distributor cap. Seemed to fix my problem - started getting easy starts back at the marina. However, I would get the same issue after being at anchor or stopping at the fuel dock. I would have to pop the shifter in neutral and give it a little throttle to start. Also started to notice some popping at around 3,000 rpms while on plane.
Next time out the engine started with a turn of the key at the dock. Went directly to fuel dock, had to give it throttle to get it to start after fueling up. Ran fine (maybe a miss here or there) for the 20 minute ride to where we anchored (a mix of no wake zones and regular zones). Anchored out for about 2-3 hours and when we were ready to go I had to give it throttle to get it started. Tried to get up on plane but it was running very rough and sputtered. Turned it off and tried to re-start the engine. This time could not get engine to turn over even by giving it throttle. Had to get a tow back to the marina.
Following day did some additional digging. Upon further inspection my flame arrestor was very, very dirty. I could hardly blow air through it. I cleaned it with brake cleaner and a strong hose and got it back to brand new. Also checked my plugs (recently replaced) they were dirty and wet, so I decided to replace them again and use the ones I replaced as a back up for next tune up since I know they are still good. Lastly I replaced the IAC valve.
Tried to start it and just wouldn't turn over. Kept trying. After about 10-15 tries it started to try to turn over. It would dieseling slightly when I stopped cranking so I popped it in neutral and gave a little throttle and finally got it started. This is on the work rack on a water hose. Once i got it started I put it in neutral and gave it some throttle. Initially was a little rough but it ran smooth after a minute or so. It was noticeably smoother than before. Had to wait until next day to put it in the water and test drive.
The next day got it in the water, again took a few tries to turn over. Once started it ran smooth, real smooth. No popping or hesitation, got to WOT of about 4800 rpms and about 53 mph. Never ran better.
The next day I get to marina and it took about 15 tries to get it started. would crank and crank and when I turned key off it would sputter a little. Got it started by shifting to neutral during that stutter and giving it a little throttle. Once warmed up I shut it off and am able to start "right" back up rather easily. However, went to the gas dock, put some fuel in and took a couple of tries again to start it after fueling up. Once started ran perfect again. WOT and top speed reached easily. No hesitation.
Next time at the marina I put it on a work rack and checked the fuel pressure (thank God for youtube and auto zone tool lending program). The fuel pressure checked out fine. Low Pressure was 12 psi and the high pressure pump was at 50psi, both within spec. Removed the fuel pressure regulator , inspected it - a very little amount of debris/dust on the screen. I cleaned it up with carb cleaner and reinstalled. No issues with the oil either.
Boat will not start at all now. Checked with marina mechanic to see if they could take a look. They told me it would take three weeks to check it out. Did some searches on the forums. Saw that someone had a similar issue and it was the coil. So I decided to change the coil. The boat fires right up. I turn it off an on multiple times...fires up each time with a turn of the key. I'm on the rack so can't test on the water for a few days.
Yesterday I get the boat in the water - fires right up. Head to the gas dock, get some fuel, fires right up again. Runs perfectly on plane - I anchor out. Turn the boat off. I turn it back on and it fires up but I sense not as quickly as before. After a couple more tries I have to give it some throttle to start up. It starts right up with throttle. Go back to the marina. Put it back on a work rack and it turns over with key.
What am I missing?
1. Anti-siphon valve? I tried to replace the anti-siphon valve but its in a difficult place to get any leverage on the nut and it seems to have some type of sealant or cement on the threads. Any tips on removing the sealant? Maybe the valve is not functioning properly after the fuel tank gets stirred up?
2. Fuel injectors? Would the boat run great once started if the fuel injectors were the issue?
3. Any other ideas? Other things I should check? I think I maxed out my mechanical ability.
The two things that I know were wrong and resolved were the coil and the dirty flame arrestor.
Thanks in advance for any help.