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Puma Jim.
I am looking to replace my dash unit with a Humminbird 798C SI combo on my Classic. I have a few questions, Does anyone currently have this unit? Do you like of dislike it? Do I get with the internal GPS or separate GPS puck. I know its important to get the puck as close to the transducer for accuracy so mounting it on the back of the boat is ideal etc. Can I mount the transducer on the 6 inch manual jackplate or do I have to drill into boat which I REALLY dont want to do. I have been to BPS a few times this week checking it out and I think its a great unit except the display seems small? I love all the features of the unit. I am upgrading big time from a 585 C which I sent back to Hummingbird last week. They want $150 plus shipping to repair the main board. Just figured it would be better to upgrade. Any suggestions appreciated.ThanksSam
I know many folks have the 798SI Combo units and love them. I had one on my Baycat and didnt like it at all. The mapping/gps side of it was fine, the sonar was not good at all. It never could hold the bottom like it should. I sent it back to HB when it was a month old. They said they had to load new software into it and sent it back. It still didnt work right. Depth would jump all over the place, even while sitting still. I think my situation was an isolated one though. (just my luck ) Ive got a 997 on my 09 Cougar…it works great. I think most guys mount the SI transducers on the jackplate and they work well. My Baycat and my Cougar had the transducer mounted to the transom by the factory on the Baycat, by the dealer on the Cougar.
I have a 797C SI and like it very much… 2 years with no problems. The 997 or bigger screen would be nice, but Im happy enough with what I got.Most guys say to go with the external antenna as the internal sometimes loses signal. I dont really think the location of the antenna is all that critical, but you have to be aware of any “offset” relative to your TD. I think accuracy is limited to somewhere around 2 meters. There are several TD mount options. Check out my profile for some pix on one way you can mount to the jackplate. Downside is my jack plate is no longer adjustable unless I remove the bolt for the TD. But I havent felt the need to change my engine height since I got the boat. I purchased the angled piece of galvanized sheet metal at Lowes. No issues with the TD, except it comes out of the water at high speed. I dont mind that as I still rely on my flasher when Im on plane and that way the HB ducer is completely out of harms way when running fast. The SI only works at speeds up to a fast idle anyway. The good thing about this mount is the TD is very well protected but will still tip up if I ever skim over a treetop.My two pence
The 7 series Side Imaging units are awesome little units but if youre looking to split the screen they are a bit small. Actually any 5″ unit really is small for splitting. I always like to put the external GPS antenna on the bow of the boat so I dont run over my spots… no sense seeing them 20 feet after you get on top of them…. regarding the transducer… jackplate mounts are the easiest by far.. depending on the plate you have you can drill a hole in the bottom side and thru bolt the transducer right to the jack… just remember to give the ducer a bit of nose down angle to compensate for the boat sitting rear end low when idling around… this will give you more accurate depth and imaging readings…JP
I have the 798 in the dash, external antenna on the rear deck, Inter Link, and a 788si on the front. Love the unit, added down scan to it in January. The only issue I have seen is that if I get too much air running under the boat the depth will jump all over when running upper 60s.
Thanks everyone. Appreciate the input. I have the CMC 6 inch manual jackplate. I am going to mount the TD there. Just hate like heck to drill into her. 2000 Classic with a 200 Merc EFI – she is still new and well taken care of. Too many girls fastpitch softball and volleyball games with my daughter. No time to take the kitty out. Today she felt water – that is I washed her off from the winter grime. Looking forward to taken her out for the first time next week while on vacation. Of course I will also be installing the new unit!!!ThanksSam
If I had the choice I would go with the external antenna for GPS. Unfortunately I went internal. The internal has weak signal strength resulting in erratic speed and position readings especially at low speeds. The unit will never lock on through WAAS or enhanced signal with the internal antenna. Humminbird is in complete denial about this issue. They say they havent heard any complaints about this. I managed to find all sorts of people with the same issue.
I got one at cabelas the other day and it is $100 cheaper than bassPro price. I will be putting it on the front and I have a 998 in the dash. Checkout cabelas web site
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