Volvo Penta 5.7 no spark

[muc]

This engine uses a Lever Based Throttle System. Basically what this means, If you set the throttle lever to half way (50%) this will command the ECM to try to maintain a certain RPM (lets say 2600 rpm as a guess for this engine) so the ECM will try to keep engine speed at 2600 rpm no matter what load is on the prop.
You need to watch TCP Actual %, TCP Commanded %, TPS Commanded % and TPS Actual % on a scan tool and see how they relate to each other to see if the system is working as designed.

This engine should not have a IAC.

 

[mkor]

Hello everyone, after changing the fuel pump I don't remember what pressure I had, but I got out on the palner and went 3200 rpm at 22 knots. Sometimes my speed spontaneously increased. A month has passed and I can't get into the glider, I can't rise above 2800 rpm. I have reviewed everything again many times. But I can't find the reason.

The only thing that confuses me is the pressure in the rail.
When I turn on the ignition, the pressure is 55, after turning off the pump it drops by 50. When I start the engine, it runs at 48. At 3000 rpm, the pressure is 46. I have not tried it in motion and under load, but it may be less. If you turn off the engine for 1 hour, the pressure does not drop. Please tell me if this could be my problem?

I bought a non original pump for about £50. The original is 4 times more expensive.

 

[alldodge]

I don't see the pump being the problem, but need to get MUC's input. Being the 4the Holiday it could be a few day before he gets back

 

[mkor]

I don't see the pump being the problem, but need to get MUC's input. Being the 4the Holiday it could be a few day before he gets back

It seemed to me that my pump does not provide the required number of liters per hour, so everything is fine without load, but there is not enough fuel under load. I also can't rule out another problem, but while I see 46 at 3000 rpm and at the same time I watched several videos on YouTube on the exact same motor other people have 50 at 3000 rpm, I don't know if I have a problem or not. The book writes 50-60.

I'll be waiting for any information, thanks.

 

[muc]

Not all gauges are accurate, might want to try a different gauge.
If you want to test for enough fuel under load, you must test the fuel pressure while you’re under load. When I watch the video you posted it looks like you might be testing without enough load. If you don’t have a helper, I would use tape or tie wraps to position the gauge outside the engine compartment so you can see what the pressure is when at full power.

Have you repaired the wiring at the key switch? Loose connections can cause all sorts of problems.

Has this engine been scanned at the RPM the problem happens at?

 

[mkor]

Hello. This is an old video, I'm going home now and will post a new one, you can see it better there. I have repaired the key switch. The scanner shows no errors.

 

[mkor]

Not all gauges are accurate, might want to try a different gauge.
If you want to test for enough fuel under load, you must test the fuel pressure while you’re under load. When I watch the video you posted it looks like you might be testing without enough load. If you don’t have a helper, I would use tape or tie wraps to position the gauge outside the engine compartment so you can see what the pressure is when at full power.

Have you repaired the wiring at the key switch? Loose connections can cause all sorts of problems.

Has this engine been scanned at the RPM the problem happens at?

Since I stopped coming here I have made a couple of long crossings at 5 knots, I was pulling the dinghy and didn't want to go any faster. After that, I found that I could not get into the planner. I didn't even understand how it happened. But if immediately after replacing the fuel pump, I easily went into the glider, but my engine speed and speed spontaneously increased. Now it took me several minutes to enter the glider, as if I had 20 people in a boat. But the revs stopped spontaneously rising. The only thing left is fluctuations in rpm between 1000 and 1500 at + -200 rpm.

I replaced the spark plug wires, replaced the throttle position sensor. I installed a clip instead of a mesh on the check valve. I bought, but have not yet replaced the MAP sensor, injectors and candles. And I had a question, but is it a problem in the pump. I did new fuel pressure tests in the low and high circuits. I also tested with a vacuum gauge. I also checked the compression. Compression is fine, the vacuum gauge shows a fault that I can't determine. The scanner showed nothing.

I also installed a new low pressure pump that I had. I checked the anti-siphon, it works, but just in case, I washed it in WD40.

 

[mkor]

Here on the video there are fuel measurements in the low and high circuits. And also in the last video (IMG_1548.mov) at 3000 rpm, the pressure drops by 46.

 

[mkor]

Here are the maximum and minimum compression measurements.

 

[mkor]

And now the readings of the vacuum gauge, I tried at different speeds. I tried to disconnect the wires from the distributor and injectors to try to find the problem. But all past.

According to the polvo penta book and the readings of the vacuum meter, I either have a problem with the valves or with the ignition. But I'm still tormented by fuel pressure.

 

[muc]

Alert ---- I was wrong. This is a IAC engine.

This engine uses a Lever Based Throttle System. Basically what this means, If you set the throttle lever to half way (50%) this will command the ECM to try to maintain a certain RPM (lets say 2600 rpm as a guess for this engine) so the ECM will try to keep engine speed at 2600 rpm no matter what load is on the prop.
You need to watch TCP Actual %, TCP Commanded %, TPS Commanded % and TPS Actual % on a scan tool and see how they relate to each other to see if the system is working as designed.

This engine should not have a IAC.

This is ALL WRONG! I had a brain fart and didn't think I needed to look at the manuals to answer your questions. When I get some time I'll relook at this and post.

 

[mkor]

Here on the video there are fuel measurements in the low and high circuits. And also in the last video (IMG_1548.mov) at 3000 rpm, the pressure drops by 46.

1 division per gauge = 2 psi

 

[mkor]

Alert ---- I was wrong. This is a IAC engine.

This engine uses a Lever Based Throttle System. Basically what this means, If you set the throttle lever to half way (50%) this will command the ECM to try to maintain a certain RPM (lets say 2600 rpm as a guess for this engine) so the ECM will try to keep engine speed at 2600 rpm no matter what load is on the prop.
You need to watch TCP Actual %, TCP Commanded %, TPS Commanded % and TPS Actual % on a scan tool and see how they relate to each other to see if the system is working as designed.

This engine should not have a IAC.

This is ALL WRONG! I had a brain fart and didn't think I needed to look at the manuals to answer your questions. When I get some time I'll relook at this and post.

thank you so much, I'll be waiting as the local official service couldn't find the problem and left.