Stewart Warner Tachometer replacement

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Oct 8, 2007
Panama City area
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Vessel Make
Mainship 30 Pilot II since 2015. GB-42 1986-2015. Former Unlimited Tonnage Master
I have decided it is time to replace the old model 811531 SW tachs associated with the model 811532 senders on my Ford-Lehman 120s.* Any ideas on sources?

If you haven't already done so, check the Grand Banks owners forum (the "good" one put together by Bob Lowe and Frode). The issue of replacement instruments has come up a number of times, and if you can't find the references in the archives aske the question again. You should get a number of suggestions by GB owners who have done this.
My link to that site was not working last night, but I'll try it soon. Thanks.
Rich, call Lauderdale Speedometer 954 522-4885 They can give you your options and prices.
I did call down to Lauderdale and had a good talk with the gent there.* He came up with the same SW 82620 unit that SW-proper and another vendor mentioned to me.* I am getting two to replace the port engine's tachs.* Once that is done to my satisfaction, I'll go back to him and get two more for the stbd engine.*

He notes that unlike my original tachs, there is no adjustment setting screw on the 82620 - probably a good thing.*

I asked about the possibility of swapping the old heads for digital heads whilst using the original 811532 pulse generators on the sides of the engines, and he thought it would work but was not sure enough to encourage me to spend 200 bucks apiece on them (nobody wants to accept returns on electrical items).* Going to go with what we are pretty sure should work.

Thanks for the number - as you probably remember from your time here, we are pretty much in the woods here in NWFL when it comes to stuff and knowledge like this.
Glad to have helped. I remember my time at Millers.
Rodger Wrona
Here is a really good source for replacement gages.

About the only thing they don't have is the one I need... a square format engine temp. gage for my 1986 Krogen.
Hey Keith, if you have VDO gauges like I do, VDO makes a new full line of gauges that will accept the square bezel off your old gauge.
Can you get them locally from Blue Water et al, or do I need to head to VDO's web site? Thanks!
Well, I ended up having to get new senders as well as the four SW tachs.* THAT was expensive, but unfortunately necessary as the 36-year old originals were really getting inaccurate.*

These new tachs require three-wire prallel conections vice the two-wire looped originals.* As the originals were wired in a loop, that is the signal wire went from the senders to the flying bridge tachs before going down to the lower station tachs and thence to ground,*I was faced with the requirement to convert them to papallel.

Since one of the new wires is power, I eliminated the need to run a third parallel wire by taking power to the senders from the engine oil pressure senders of each engine, and power to the tachs themselves was taken from the other instruments of the respective engine at each panel.* The two original wires were easily converted from loops into two parrallel wires by reconnecting from the local TBs to the panels and a couple of short jumpers to get the connections I needed.*

Things are running fine (verified by handheld digital tach), and interestingly, the dip switch settings of the tachs were set differently out of the box but worked fine as they were received without alteration - go figure.
IF you can stay with dedicated tach sender units , and avoid the alternator pulse counters , esp if twin engine.

Yep, that was*my goal.* I was pleased to find that the new senders threaded right onto the old Lehmans in place of the original dedicated senders.* Over the years,*I had feared replacement would require moving to an alternator tap - glad I avoided that one.
Am interested in what sending unit was used to replace the SW 811532 that goes to the SW 811531 tachometer. Thanks
The senders I used are SW 82623B.
Old senders

Amy Any chance you still have the old senders? My port engine has has gotten flaky . Single station set up. Current sender is 811532.
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