Twin engines - single trim switch

[CUSAC]

I've got twin Merc 90 2 strokes (1997) and they weren't originally fitted with trim senders & gauges. Rather than having the expense of fitting these and to avoid always turning round to check they are trimmed together has anyone fitted a single trim switch on their console?

Fairly handy with DIY stuff but I suspect the wiring involved to have a single switch but also be able to use the individual switches on the throttles would be above my level!

Any thoughts welcome. Thanks!

[Pikey Dave]

Originally Posted by CUSAC

I've got twin Merc 90 2 strokes (1997) and they weren't originally fitted with trim senders & gauges. Rather than having the expense of fitting these and to avoid always turning round to check they are trimmed together has anyone fitted a single trim switch on their console?



Fairly handy with DIY stuff but I suspect the wiring involved to have a single switch but also be able to use the individual switches on the throttles would be above my level!



Any thoughts welcome. Thanks!

Not 100% sure what you’re trying to achieve, but; if you’re trying to trim both engines simultaneously from one switch, it only works “ish” due to differences in speed from the trim pumps, they soon get out of sync. It’s pretty straight forward to do & will involve a relay. My last RIB had twins with individual trim switches on the binnacle & a common one in the throttle.

[CUSAC]

Originally Posted by Pikey Dave

Not 100% sure what you’re trying to achieve, but; if you’re trying to trim both engines simultaneously from one switch, it only works “ish” due to differences in speed from the trim pumps, they soon get out of sync. It’s pretty straight forward to do & will involve a relay. My last RIB had twins with individual trim switches on the binnacle & a common one in the throttle.

Yes the idea was to trim both simultaneously. Hadn't considered slight differences in pump speeds. Maybe it's not worth the hassle for what it solves. Might just keep on the lookout for second hand trim sender units.

[Fender]

A lot of twin helms have a master trim switch for both engines and then individual handed trims for 'trimming' / fine adjustment, it would be relatively easy to retro fit a master and still have the individuals, you'd just need a 'momentary on / off / momentary on' marine grade switch with the correct poles

[jwalker]

As Pikey Dave said! It is a fairly common arrangement and though the motors do get out of sync if you trim them both fully down initially then trim out for running they'll stay pretty much in sync over that short trim time.

You'll need to pick up the connections on the present trim relays and feed a supply to them both from a separate, single relay triggered by your new trim switch. Alternatively, if you can source a double pole trim switch it can be wired one side to the left trim switch and the second side to the right trim switch so when it is pressed both engine's trims are energised.

[breezeblock]

Originally Posted by CUSAC

I've got twin Merc 90 2 strokes (1997) and they weren't originally fitted with trim senders & gauges. Rather than having the expense of fitting these and to avoid always turning round to check they are trimmed together has anyone fitted a single trim switch on their console?

Fairly handy with DIY stuff but I suspect the wiring involved to have a single switch but also be able to use the individual switches on the throttles would be above my level!

Any thoughts welcome. Thanks!

ive got a trim sensor and wiring from a 2013 mariner 4 stroke if its the same your welcome to it I took it off as the smart craft needs a sensor that was different

[Last Tango]

Without trim gauges, are you still, not going to have to turn round to check if they're trimmed together? And if you're using then for trimming out "heel" does it matter as they're not going to be the same, if you're not, can you not tell from the heel when they're not?

That made sense in my head but it's been a long day..............

[CUSAC]

Thanks for everyone's thoughts. Having dug the service manual out a double pole switch looks fairly easy to graft in so will give that a go over winter.

[oracle]

I've got an old set of top mount twin controls off that vintage of engine and the old trim gauges (not the senders though).

The controls use 2 trim switches but both on the starboard lever so you can trim them separately if you need to or both at the same time with your thumb if you want to trim both at once. Are you using top or side mount?