I just recently bought a boat with 2 hummingbird graphs . The helix 7 gps gen 3 on the bow is broken. What is some good options to replace it without breaking the bank. I'm new to fishing with electronics.  Can I just buy a gen 4 and plug and fish?

Yes, you can almost certainly do that. The power plug is the same across all of the helix. The transducer will plug right in. If you keep at a 7 then both will have the small transducer (assuming side imaging units). And a gen 4 7” will have the same mounts/bracket. 
 

not sure if what you have is networked. If they are, then make sure you get a helix g4n.

@Terrel ton of new product launches from Hbird so you may find a lot of opportunities to buy on the auction sites and get the next size up for the same price. 

31 minutes ago, casts_by_fly said:

Yes, you can almost certainly do that. The power plug is the same across all of the helix. The transducer will plug right in. If you keep at a 7 then both will have the small transducer (assuming side imaging units). And a gen 4 7” will have the same mounts/bracket. 
 

not sure if what you have is networked. If they are, then make sure you get a helix g4n.

My old unit had side imaging, will I need to change ducer for gen 4 down image. Ducer is built on my I pilot? Thanks

The transducer is the same over the gen 3 and gen 4. Easy swap. If you go bigger on the new one you’ll get the bigger transducer and I would recommend using it if you go that way. It’s twice the power, 5x as long. 
 

if you decide to get another helix 7, then just get the CHO msi model and save the cost of a transducer 

3 hours ago, casts_by_fly said:

Yes, you can almost certainly do that. The power plug is the same across all of the helix. The transducer will plug right in. If you keep at a 7 then both will have the small transducer (assuming side imaging units). And a gen 4 7” will have the same mounts/bracket. 
 

not sure if what you have is networked. If they are, then make sure you get a helix g4n.

My old unit had side imaging, will I need to change ducer for gen 4 down image. Ducer is built on my I pilot? Thanks

Thanks very much 

I recommend going up a size if you can and getting the bigger transducer. I have the g4 7" with MSI. I like it but I'm on a kayak, if I had a boat if definitely want a larger screen especially on the bow, and the new transducer will give you better returns as well. 

13 hours ago, FishTax said:

I recommend going up a size if you can and getting the bigger transducer. I have the g4 7" with MSI. I like it but I'm on a kayak, if I had a boat if definitely want a larger screen especially on the bow, and the new transducer will give you better returns as well. 

while I agree with this advice generally, in this case that would mean new brackets and running a cable.  A 7” unit is a plug and play swap.