Location of trolling valves and emer. engine shutdowns

The trolling valves trigger (if so equipped) are often a button on the controls. A lot of boats don't have emergency shut downs, but on the 56 Hatteras MY I run they are (2) pull handles located low on either side of the front of the helm. Yes there should be a remote switch for the engine room fire extinguisher system.

They are usually chrome T handles on the flybridge. Both Bertrams and Hatteras usually had them. What year boats are we talking about? If you pull the Shutdown cables on a detroit diesel, you have to physically go down to the motors open them and lock the dampers back open again after pulling the engine shutdowns. On newer electronic engines the shutdowns usually are in the engine room on the computer boxes.

What year boats and what brand gears are we talking about in regards to the trolling valves? Cannot answer that question without more information.

Capt J is correct in asking for more information. Newer engines have the "trolling valves" built into the control system, older vessels had separate controls- a third set of handles- which were the trolling valves. If you see three sets of T handles on the bridge then one of the sets is the trolling valves. If there are two sets then one set is gear selection for each engine and the other set is RPM for each engine. If there is one set then the gear and RPM is combined; in which case you have some sort of different method to allow the engines to be in forward or reverse slower than idle forward.

Can you still have Halon on a yacht?

Although most people still refer to it as such, it's not in the U.S.

Production and import of halon was banned in the US on Jan 1, 1994. However, existing systems are still allowed and one can in certain circumstances even purchase recycled halon to recharge them. Also, if you remove any you're supposed to send it to a recycler.

It's much like "we don't have any way to get rid of what is out there so we'll keep recycling it but we won't allow any more."

Yes, at least on private yachts here in the U.S. it is grandfathered in and can be re-certified providing it has not been over 5 years since it's last certification. It Cannot be refilled, so if the bottle is low and does not pass certification, you have to then upgrade to the new system and I believe pay to have the bottle disposed of.

You should not need trolling valves for trolling dead rigged ballyhoo or artificial lures on those boats as they're slow enough with 1 or 2 engines in gear, only for dragging live bait. They usually never got used. In that case there should be another set of levers on the bridge for the trolling valves. Usually 1 lever per gear only as you do not have throttle, just the amount of slippage of the gear with the engines at idle rpms, typically.

Emergency shut-downs are a t-handle that pulls a cable that closes the air damper on the engine, most Hatteras and Bertram of that era had them on the bridge. If you have a Halon or automatic fire system, it should shut the engines and generator off automatically. If the air dampers on the Detroit Diesels are pulled/closed you have to manually open them on the motor and re-attach the locks/holders to hold them open on each engine.

How does a trolling valve operate ? Is it something you can add to a boat ?

It reduces the clutch oil pressure allowing the clutch to slip so you can run slower than fully clutched in at idle.

On the ones I have encountered there are fairly clear instructions as to the amount of power to be applied when using them and the duration of operation to avoid overheating damage.

Most of the trolling valves I dealt with, the motors are to stay at idle at all times and you just clutch them in all of the way for fully locked up or turn them off and switch over to gears and throttle.