bertram31.com

I recently got a 76 28 fly bridge. The boat has a ton of different electronics screwed to the helm over the years. I’m and glassing up all the holes and I am going to start fresh. I’m just curious as to what this is? https://imgur.com/gallery/Tv0ulZG The suspense is killing me! Thanks for the help!

I have one of those also. I believe that the guy who was showing the boat for the deceased owner’s daughter told me that it was an engine synchronizer.

pschauss wrote:I have one of those also. I believe that the guy who was showing the boat for the deceased owner’s daughter told me that it was an engine synchronizer.

Ding ding we have a winner. It is an engine synchronizer!

It has two flashing lobes that flash as one as engines come into sync...

I googled "Judson Engine Synchronizer" and found a picture which looks like mine. Some of posts that I found suggest that they cause problems with electronic ignition systems.

That is a really old one. Used to have one for the big blocks. It worked for a while, but after running the boat a while you learn to sync them by ear. Best way to learn is to have someone run the boat, while you stand in the cockpit. You can really hear when they out of sync when you are down there. Have them speed up the engine that is slow, or pull back on the one that is running faster. If they adjust the throttle slowly, you will learn to hear the difference.

Thank you all very much for the help.

Mine had that too until I upgraded to a Faria sync. The old flasher worked OK but did not tell you which side was slow.

The unit I had 3 lights. When the center green light was solid you were sinked. If the either light to the side of the green blinked that was the slow engine.

I had that three light one too, after the single strobe globe thingy.


When the three light died...it was mostly just the ears and flow scan to dial me in.

The flow scan I am going to miss...

As everyone else said it's a Judson engine scryno, most early Bertram's had them. Steady flash you were in scyn. Another way to see if your in scyn is to look at the wake if one side is higher than the other your out, wave height the same your in scyn. The area that your watching is where the first white water is coming together off the transom, the white hump area. Sound works also.
Pete Fallon

Maybe I'm missing something but doesn't matching the RPMs sync the motors? I've never understood why you'd need this with tachs on the dash

Peter--I never found my tachs that accurate or the harmonics of the props may require a slight difference in rpm to attain that pleasing rhythmic sound. I sync mine by ear.

I am sure the new computer controls and digital gauges of today's powerplants are far more reliable than my old school gas big blocks.

Peter

As Craig Mac normally the tachs are not that accurate. Mine are off very slightly, not much but enough.

Even with good Tachs, they will only get you so close to being in sync.

...and the engine synchronizer got me closer

to get even better I used the flowscans. When both engines were running well, tweak throttles to the same burn rate and they were perfectly in sync.

I sync by ear, but lately have been using boost gauges to make sure that both engines are doing the same amount of work.

If you use the same gears on a counter rotating setup, matching exact engine rpm will result in one prop spinning a little faster than the other.....

Had Glendennig electronic throttles put on when I added the tower to Priceless. Sync worked but not very well. this past year got digital tachs at both stations and a dedicated sending unit for the engine synchronizer and it's amazing how close they are. At cruise I am typically within 10-20 rpms of each other. the Yanmmar 315s run and sound great when they are that closely matched. Everybody on her has noticed the difference. Worton Creek found the sending unit that mounts to the front engine pulley since using the alternators wasn't up to snuff. I highly recommend this setup..

Also found that with the old tachs off the alternator I was actually running 150 rpm less as measured by timing light. Its amazing how inaccurate they can be and I was wondereing why my 31 was so slow at 3150-3200 compared to what members posted with the same setup