B7800 dash panel removal? Stop solenoid removal tip.

[Mudder]

Well the 2004 B7800 crank but intermittent no start issue returned (no solenoid click heard on key start position). Removed the stop fuel solenoid and it fires right up, and can stop the engine by manually depressing the fuel cutoff plunger contact inside with a finger.
Supplied 12v + to one solenoid plug pin, ground (-) to its body on a bench test and it vibrated in and out like a machine gun, no response when + power to the other single pin. Should it stay retracted under constant power supply? Is this a bad stop solenoid or should I look elsewhere?

Also need advice on how to remove the lower dash panel to check wiring and a potential relay issue referenced in other posts (relay ACA12115 / CA1a-12V-A-5). I have successfully freed the upper dash panel with guages.

Similar fixes by others? Thanks in advance.

PS. Saw comments on difficulty with removing the inside bolt on the stop solenoid due to little clearance, but was successful using a deep 1/4 inch drive 10 mm socket and 1/4 inch ratchet. Getting the inside bolt started back in the hole is more difficult.

 

[BigGG]

Well the 2004 B7800 crank but intermittent no start issue returned (no solenoid click heard on key start position). Removed the stop fuel solenoid and it fires right up, and can stop the engine by manually depressing the fuel cutoff plunger contact inside with a finger.
Supplied 12v + to one solenoid plug pin, ground (-) to its body on a bench test and it vibrated in and out like a machine gun, no response when + power to the other single pin. Should it stay retracted under constant power supply? Is this a bad stop solenoid or should I look elsewhere?

Also need advice on how to remove the lower dash panel to check wiring and a potential relay issue referenced in other posts (relay ACA12115 / CA1a-12V-A-5). I have successfully freed the upper dash panel with guages.

Similar fixes by others? Thanks in advance.

PS. Saw comments on difficulty with removing the inside bolt on the stop solenoid due to little clearance, but was successful using a deep 1/4 inch drive 10 mm socket and 1/4 inch ratchet. Getting the inside bolt started back in the hole is more difficult.
View attachment 808487

Sorry, I can't be sure about this. But I think you have the style solenoid with an internal switch. The two pins are for the two coils, but the pull-in coil has a switch in series with it. As the core pulls in, it opens the switch to that coil and the hold coil keeps the core pulled in. The connector wires those two pins in parallel, they're hot at the same time.

If you power just the pull-in coil, it will oscillate as that switch opens and closes with the motion of the plunger. If you power both pins, the solenoid should pull in and hold. If you power just the hold coil and push the plunger in, it should stay in.

See if you get power to both pins when you turn the key on. If not, you may have a broken connection.

 

[orezok]

Here is the parts diagram for the "cowling". Looks like one bolt on top and then lift up.

 

[Mudder]

Sorry, I can't be sure about this. But I think you have the style solenoid with an internal switch. The two pins are for the two coils, but the pull-in coil has a switch in series with it. As the core pulls in, it opens the switch to that coil and the hold coil keeps the core pulled in. The connector wires those two pins in parallel, they're hot at the same time.

If you power just the pull-in coil, it will oscillate as that switch opens and closes with the motion of the plunger. If you power both pins, the solenoid should pull in and hold. If you power just the hold coil and push the plunger in, it should stay in.

See if you get power to both pins when you turn the key on. If not, you may have a broken connection.

Thank you both for replies. Just confirmed function as you stated on a bench test, power to both plug pins simultaneously retracts and holds in the plunger in, so the solenoid seems ok. Now I need to track down why no power is going to the solenoid when installed??. Found this parts diaghram for relays.

If I find the fix, will update my post.

 

[Mudder]

Here is the parts diagram for the "cowling". Looks like one bolt on top and then lift up.

View attachment 808510

Helps a lot, thanks.

 

[crbr]

....If I find the fix, will update my post.

Linked

 

[Mudder]

Fixed.

Follow up with fix- B7800 no fuel stop solenoid activation. Crank, no start.

After months of intermittent crank but no start with no fuel stop solenoid “click”, finally fixed it by replacing the relay, ACA12115 (CA1a-12V-A-5) located inside the dash and beside the tachometer cable. Checked all grounds and even got a new battery. The solenoid passed a bench test with...

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