Nortech 390 450r or 400r engines
04-08-2023 | 08:20 PM
#1
Thread Starter
Registered
Joined: Apr 2020
Posts: 12
Likes: 1
Nortech 390 450r or 400r engines
I am looking to buy a nortech 390, I have looked at a few used boats, I am looking for a 2020 or 2021, does anyone have an opinion on the reliability of 400r vs 450r engines, is one more reliable then the other ? I have heard the 1st generation 450r motors have more problems then later generations , can anyone tell me if this is true and if so what model year 450r would be the start of the 2nd generation? Any other advice on what to look for when buying a used boat. Thank you
04-09-2023 | 04:40 PM
#2
Registered
Joined: Oct 2000
Posts: 703
Likes: 61
From: Norway
Hi!
I owned a 400R from 2017 until 2022. Excellent engine. No problems at all. However, its a rpm engine not pulling so hard from start. Its quiet, good mannered and fuel efficient. I replaced my 400R after 500 hrs use and no hick ups at all.
Took delivery of my 450R summer 2022 and I have now 200 hours on it. No problems at all. Use approx 10% more fuel on the same speed. Much more torque. It kicks you straight into plane. I can compare it to twin Mercury 2.5 EFI SS engines. So much torque. Quiet, but more a high performance engine than the well mannered 400R. Does not like that much to run slow. The 400R maintained 140F at 1,000 rpm but 450R runs at 120F. So in my view the 450R should be run at higher rpms to get proper temperature.
I got the best fuel milage at 4,000 rpms with the 400R and with the 450R its 3,300 rpm. Approx same speed.
Speed with 400R at 4,000 rpms = 48 mph. Speed with 450 at 4,000 rpms = 60 mph. Max torque for the 450R is 4250 rpms. So cruising with the 450R is 65 mph. With the 400R I had to run at 5,000 + rpm to get that speed. However, WOT rpm for the 400R is 7,000 and for the 450R 6,300 on my boat.
Good luck!
Cheeers Toffen
I owned a 400R from 2017 until 2022. Excellent engine. No problems at all. However, its a rpm engine not pulling so hard from start. Its quiet, good mannered and fuel efficient. I replaced my 400R after 500 hrs use and no hick ups at all.
Took delivery of my 450R summer 2022 and I have now 200 hours on it. No problems at all. Use approx 10% more fuel on the same speed. Much more torque. It kicks you straight into plane. I can compare it to twin Mercury 2.5 EFI SS engines. So much torque. Quiet, but more a high performance engine than the well mannered 400R. Does not like that much to run slow. The 400R maintained 140F at 1,000 rpm but 450R runs at 120F. So in my view the 450R should be run at higher rpms to get proper temperature.
I got the best fuel milage at 4,000 rpms with the 400R and with the 450R its 3,300 rpm. Approx same speed.
Speed with 400R at 4,000 rpms = 48 mph. Speed with 450 at 4,000 rpms = 60 mph. Max torque for the 450R is 4250 rpms. So cruising with the 450R is 65 mph. With the 400R I had to run at 5,000 + rpm to get that speed. However, WOT rpm for the 400R is 7,000 and for the 450R 6,300 on my boat.
Good luck!
Cheeers Toffen
04-12-2023 | 10:28 PM
#3
Registered
Joined: Oct 2007
Posts: 399
Likes: 550
From: New Smyrna Beach FL/ LOTO MM 21
There were a few updates done early on but anything after 2021 should be good. There are a lot cooling passages on the 450s so keeping them flushed and clean is a must to avoid overheats. The blowoff valves get sticky, the screens get plugged and need to pulled if they ingest vegetation, pebbles, or shells. We have a few 450s in the fleet and a couple 400s as well--If I ever get a big C.C., it will have V8s or V10s for the torque.
Joe
Joe
