V8 4.7L Vantage exhaust solenoid valves

[Daverevis]

I have been trying to get to the bottom of the Fuse 22 -exhaust note scenario.The fuse made no difference so I located the solenoid valves and found both valve gates had seized on their shafts and sheared the connections to the solenoid valves.With lots of penetrating oil and patience I have freed the valve gates in the tailpipes but obviously cannot reconnect them to the Solenoid pistons so they will have to stay in one position but I have no way of knowing if the gates are open or closed Which position should they be in for max noise,and how can I determine this position? If they are in the wrong position can this cause damage to the engine? Any suggestions will be very welcome!

[Bobajobbob]

I’ve just been through some trouble shooting on my exhaust valves and found that the previous owner or dealer had locked the valves open. My dealer liberated them again with the car on a ramp for 10 minutes. I’m not 100% sure how it was done but cable ties may have been used.

What I gleaned from watching the process is that plunger out = valves open and plunger in = valves closed if that helps.

[Daverevis]

Many thanks for your reply,which is useful.My problem is that because the solenoid connection has sheared off the butterfly valve shaft,I cannot tell if the valves are open or closed as I turn the shaft with mole grips.I think I am aiming to keep them in the fully open position as this will give a better flow through the exhaust system

[johnnyBv8]

Daverevis said:

Many thanks for your reply,which is useful.My problem is that because the solenoid connection has sheared off the butterfly valve shaft,I cannot tell if the valves are open or closed as I turn the shaft with mole grips.I think I am aiming to keep them in the fully open position as this will give a better flow through the exhaust system

Can't you hear the difference with the engine running though if you turn the shaft with your mole grips - at least on the side that isnt broken? I seem to remember (but there's a 50% chance of me being wrong - sorry!) that the flaps, if unconnected/no external input, will be closed.

[Bobajobbob]

Its a good question as to whether keeping the valves permanently closed might be bad for the car. It certainly will be obvious to hear and I can reassure you that having the valves permanently open is not a problem. If it sounds good the valves are open and if it doesn't then they are closed.

In the long run probably best to get them fixed. For me the best solution is to fit a Fuse15/22 switch so that you can run in default mode with valves closed at low revs or loud mode where the valves are always open at the click of a switch.

Now if I could find a way to mount the switch in the gear knob my life would be complete.

[V8V Pete]

Bobajobbob said:

Now if I could find a way to mount the switch in the gear knob my life would be complete.

Well I can't advise about a gear knob solution but my valves are switched via my Sport button. No need for different throttle maps when you have the BR H&T map so the Sport button now only operates the exhaust valves. Red = loud

[Daverevis]

Thanks to you all for taking the time to reply.Somehow I’m going to determine that the valves are fully open and leave them in that position

[Bobajobbob]

V8V Pete said:

Well I can't advise about a gear knob solution but my valves are switched via my Sport button. No need for different throttle maps when you have the BR H&T map so the Sport button now only operates the exhaust valves. Red = loud

Sadly where you have a sport button I have a pen

[V8V Pete]

Bobajobbob said:

Sadly where you have a sport button I have a pen

I'm sure that could be changed

[jeff5]

Daverevis said:

Thanks to you all for taking the time to reply.Somehow I’m going to determine that the valves are fully open and leave them in that position

If you look down the actual exhaust pipes using a torch you should be able to see the valves and there position. I can on my 2017 V8S.

[Daverevis]

Again,thanks to all for your suggestions.I will be getting my torch out ASAP and looking down those pipes,this should do the trick.

[BamfordMike]

When nothing is broken (spindle or linkage arm) the valve is in default open position. In open position the arm on valve spindle (red outline) will touch the stopper (green outline)



When valve is drawn closed, silent mode, the arm on valve spindle (red outline) will move to the 6-o-clock position in relation to stopper (green outline)



If your linkage from valve to arm is broken (blue line), then knowing the actuating arm is resting on the stopper, you can weld repair the system to function again. If the spindle is broken off actuation arm (yellow line) you’ll have to make sure valve is fully open and arm is resting on stopper to weld repair the system.




It’s a common job to make a new spindle or repair linkage arms. If the seizure was too bad, it’s also common to completely cut out the valve body and weld in a complete replacement unit.

To answer another question, if the valves were completely closed at 7500 rpm with the motor on full chat at 380 / 420bhp there would be no consequence other than loss of BHP.

[Daverevis]

thanks so much,this is really helpful to me.I appreciate your time.

[Bobajobbob]

I hope the OP doesn’t mind a slight post hijack but while solving my stuck valve problem I noticed that since freeing the valves the fuse box on my Roadster (left side of boot) gets very hot.

It may have always got hot and I didn’t notice because I wasn’t checking but it would reassuring to know that that is the case. I had a small doubt that in releasing the previously jammed valves that they were not fully working causing a heat build up.

Thks

[BamfordMike]

Bobajobbob said:

I hope the OP doesn’t mind a slight post hijack but while solving my stuck valve problem I noticed that since freeing the valves the fuse box on my Roadster (left side of boot) gets very hot.

It may have always got hot and I didn’t notice because I wasn’t checking but it would reassuring to know that that is the case. I had a small doubt that in releasing the previously jammed valves that they were not fully working causing a heat build up.

Thks

If the valves were permanently open (loud mode) in effect, the gas pretty much bypasses the silencer completely and goes out the tailpipe. In that case the large surface area of the silencer will not get that hot.
When the valves are closed (quiet mode), the exhaust gas channels through the large muffler. In this case the muffler will now get much hotter than if the valves were open, the large surface area of the muffler acts as a radiator and will heat up the underside of the boot area more than if the valves were permanently open and the body of the muffler ran cooler.
In either case, the heat generated is nothing to worry about, there is adequate shielding and given worst case exhaust heat output in a 40/50 Deg ambient, its all been durability tested to death.

The only error state to become concerned about is if exhaust gas is actually leaking out of the exhaust system, a leak of hot gas will cause a problem of some sort because of melting. This happens frequently on classic Vanquish. The silencer inlet pipes corrode to the extent no gas goes into the silencer and the hot exhaust gas then destroys whatever it is blown against, quite often the rear bumper.

Edited by BamfordMike on Wednesday 10th October 12:11

[Bobajobbob]

Thanks a lot Mike, very helpful info. If in doubt I'll just open the valves but what you are saying is that its normal for the fuse box to get a bit hot. I'm guessing that if there was a leak it would be audible

I did wonder if the silencer may be getting slightly hotter than usual because it has effectively been unused, possibly for years. I guess a good few blasts down the motorway should clear out any cobwebs/blockages with plenty of air circulating.

thanks again