Trojan Boat Forum

Does any one know the deadrise angle on the '78 F-26 hull. I'm going to order the new Garmin chart plotter this afternoon and need to know this angle to get the correct sonar transducer.

Any help would be appreciated

The deadrise of a 1971 F26 is 5 degrees. I believe the deadrise is the same for a 1978 F26.

Thanks for thee info Dog, I think your right. I ended up going to the marina where the boat is being stored indoors and tried to measure it up to get a rough idea with a machinists protractor. My neck is still in the healing phase so I really couldn't get right under the boat to measure but from what I could see, it looked to be in the 5-6 degree range. I therefore ordered an Airmar B117 bronze thru hull transducer rated for a 0-7°deadrise.

Thanks for the reply.

Remember the dead rise will vary bow to stern . But you should be find with what you ordered

prowlersfish wrote:Remember the dead rise will vary bow to stern . But you should be find with what you ordered

That's correct Paul, it does seem to hold that deadrise from the transom to a little less than 2/3 the distance to the bow from what I could see. I'll be installing the transducer under the cabin floor just below the steps so it should be OK. The transducer for my Garmin 240 Blue is on the opposite side of the keel at this location and there will be about 18" between them. Think there will be any interference issues between them?

Maybe /maybe not . If so you could run them at different Hz the garmin is 50/200hz , I believe you could change from one to the other . I have 2 sounders but don't have any issues . but then again rarely use both at the same time .

i beleive it is 12 degrees about three feet back from the engine room bulkhead

32pacemaker wrote:i beleive it is 12 degrees about three feet back from the engine room bulkhead

Thanks for the reply 32,

You got me thinking that I should go and do a more accurate measurement of the angle so that's what I did this afternoon. I measured a location 4" starboard of the keel about a foot ahead of the engine room bulkhead and found it to be about 7-8 degrees. This puts it right at the upper limit of the transducer that I ordered (0-7°) and the lower limit of the next choice of transducer (8°-12°). I also noticed, when measuring a foot further to starboard from the keel, that the the angle became greater. It was actually difficult to gauge due to a slight curvature in the hull at that location but I, say that the average angle there out to the side of the boat was indeed about 12°.

I put an Aimar B60 in about the same location on my F26 as you are describing but a little further out toward starboard. I think I remember the hull angle where I cut the hole was around 10 degrees. I installed the 12 degree tilted element and it is working fantastic. And another thing I may have just got lucky on. I ordered a Lowrance HDS 5X to use as a back up fishfinder. It came with the transom mount 50/200 transducer. I installed it on the transom just in toward center of the port side trim tab. I really figured there would be a lot of turbulence in that area so close to the prop and the unit would not read well while running. I was very surprised in that it reads better than any transom mount transducer I have ever had. There is no interference and it holds bottom 100% of the time while running. Don't know if this would qualify as a "myth busters" busted myth in that you can't put a transom mount transducer on an inboard boat but mine is working very good.