V7II fuel pressure relief valve

[redhawk47]

My thread on V7 fuel filter, http://wildguzzi.com/forum/index.php?topic=92379.new;topicseen#new, also raised the question about a component attached the pump mounting plate that had no hoses connected to it. Consensus it that it is a fuel line pressure relief valve and there is plumbing in the mounting plate.

A thought has arisen that this component might be related to another issue, "pauses" in the power. These pauses are more apparent when traveling about 30 mph at steady throttle, but happens at all/most speeds. The engine seems to "miss a beat" as if it didn't fire on one stroke. The "miss" is not regular, but random, but frequent, perhaps one or two per second. I feel it in the handlebars, but do not hear it in the exhaust.

The thought is that the fuel line pressure relief valve is relieving too much pressure, and/or "fluttering", causing a drop in pressure and not enough fuel for a full burn. Could this be the cause of my "pauses"?

I am willing to install a new fuel line pressure relief valve to test the idea. However, the MG parts diagram lists the pump assembly but not the individual components. Does anyone know the mfg and part number for the valve? I did an online image search and did not find anything similar. Any suggestions?

[Vagrant]

have you fixed the spark plug boot issue.

[fotoguzzi]

unlikely your problem. look more into the plug boot suggestion.

[pete roper]

The only thing that goes wrong with FPRV's is they rust out on models with a pump assembly in the bottom of the tank if they are stored for long periods in damp conditions with a near empty tank.

I doubt very much if your problem is relief valve related.

Pete

[Kev m]

The only thing that goes wrong with FPRV's is they rust out on models with a pump assembly in the bottom of the tank if they are stored for long periods in damp conditions with a near empty tank.

I doubt very much if your problem is relief valve related.

Pete

I'm with Pete, very unlikely that it would manifest itself that way. Pressure regulators are simple mechanical spring and diaphragm devices. When mounted internally, they generally either stick open (steady low pressure) or stick closed (steady high pressure).

Look for electrical issues.

[redhawk47]

have you fixed the spark plug boot issue.

Yes, I have changed to NGK plugs and connectors.

[Vagrant]

Don't get mad for my asking but did you cut a tiny bit off the end of the wire and screw them on. next did you check up at the coil to make sure they are tight there.
next and this has been an ongoing issue with EV's that sit I would pull each fuse and spray with some type of electrical contact cleaner. it's amazing what the tiniest bit of corrosion will do. I haven't had to notice yet but if it has the 5 pin relays like old bikes do them too. Also I never trust a ground so why not remove them all and clean them up.

[redhawk47]

Don't get mad for my asking but did you cut a tiny bit off the end of the wire and screw them on. next did you check up at the coil to make sure they are tight there.
next and this has been an ongoing issue with EV's that sit I would pull each fuse and spray with some type of electrical contact cleaner. it's amazing what the tiniest bit of corrosion will do. I haven't had to notice yet but if it has the 5 pin relays like old bikes do them too. Also I never trust a ground so why not remove them all and clean them up.

Yes, I cut off the end of the wire before screwing the new caps on. I checked the connection to the coils. I also replaced the right side coil, based on a report in MGNOC newsletter of similar issues. The bike is a 2016 V7II purchased a year ago, with 8000 miles, so I would thing that the connections would be in good shape, but I will check them.

[rodekyll]

The fast way to resolve a question of fuel pressure is to install a fuel pressure gauge just upstream of the injectors.  You can do it with a simple brass T with hose barbs on the T's cross and a $10 mechanical pressure gauge on the T's downleg.

But I agree that pressure probably isn't the problem unless the pressure drop is coming from somewhere else, like a kinked fuel line or plugged filter.  Doesn't mean it's not a fueling issue though.