Official 400EC thread

[Mikentucky]

So the admiral wants to take a little trip to her parents house this coming weekend, a trip down the Ohio river. There is one set of locks (McAlpine) along the way, but NO fuel stations. The trip is about 50 nautical miles one way, maybe an extra 20 miles spent entertaining while we're there. It's downriver to get there, upriver to get home. Our boat is named "Lollygagging" for a reason...I don't mind running slow LOL

Being conservative, can I realistically (easily) make a 100-150 mile round trip down and back up the river, or would I possibly not have enough fuel even if I stay out of the throttles?

I have the usual 150 gallon tanks for each side. I've looked up the Mercruiser charts on theoretical burn rate for my gas 7.4's with 2-barrel carbs at different RPM's, but with no flow meters I haven't calculated with my specific 400EC how far she goes per gallon, at what speed or RPM is her "sweet spot" for burning efficiency. I won't have the opportunity to do any real world calculations before we go, so I'm just asking for opinions based on "your experience with your 400EC"....

Thanks!

 

[GregM]

I removed the starboard side helm seat for new upholstery and found that there is a seat adjustment lever on the right side of the seat for forward, and rearward adjustment, and the left side has a broken off stud in the rail. Can anyone tell me if where I found the broken stud there should be a Tee handle that would lock down the left side of the seat after a seat adjustment was made?

Yes, there is a "L" shaped handle you lift up on slightly to release the locking so seat can slide. Its nice to use because when you're not driving you can slide seat forward and give the people sitting in seat behind it a lot more headroom making it more comfortable. The edge of the handle is about flush with the lower half of seat.

 

[Mikentucky]

I removed the starboard side helm seat for new upholstery and found that there is a seat adjustment lever on the right side of the seat for forward, and rearward adjustment, and the left side has a broken off stud in the rail. Can anyone tell me if where I found the broken stud there should be a Tee handle that would lock down the left side of the seat after a seat adjustment was made?

I know the adjustment handle is there on mine, but I didn't need to adjust it so I'm not sure what other mechanisms it interacts with---that's a long seat, so I figure there is something to move/secure it on the left side as well. I'll be down at my boat either this evening or first thing in the morning, I'll let you know what I find if no one responds before then

 

[Oh La La]

Hi All,
Looking to get new props for my 1998 400 EC, currently I have 20x20 4 blade bronze.
Looking to change over to nibril any recommendations regarding 3 blade vs 4 blade. I believe out of factory it had 20x21 3 blade bronze. Any out there and how do the perform?

 

[GregM]

Hi All,
Looking to get new props for my 1998 400 EC, currently I have 20x20 4 blade bronze.
Looking to change over to nibril any recommendations regarding 3 blade vs 4 blade. I believe out of factory it had 20x21 3 blade bronze. Any out there and how do the perform?

I have 3 balde Acme Nibral props that seem to be propped correctly for my boat. WTO is 4300 RPM. I can say the boat performs well. Comes out of the hole quickly, cruises at 18-19mph at 3k-3.2K, depending on lake conditions, and has a WOT speed of 30mph.

 

[GregM]

So the admiral wants to take a little trip to her parents house this coming weekend, a trip down the Ohio river. There is one set of locks (McAlpine) along the way, but NO fuel stations. The trip is about 50 nautical miles one way, maybe an extra 20 miles spent entertaining while we're there. It's downriver to get there, upriver to get home. Our boat is named "Lollygagging" for a reason...I don't mind running slow LOL

Being conservative, can I realistically (easily) make a 100-150 mile round trip down and back up the river, or would I possibly not have enough fuel even if I stay out of the throttles?

I have the usual 150 gallon tanks for each side. I've looked up the Mercruiser charts on theoretical burn rate for my gas 7.4's with 2-barrel carbs at different RPM's, but with no flow meters I haven't calculated with my specific 400EC how far she goes per gallon, at what speed or RPM is her "sweet spot" for burning efficiency. I won't have the opportunity to do any real world calculations before we go, so I'm just asking for opinions based on "your experience with your 400EC"....

Thanks!

I've crossed Lake Michigan with my boat several times, with full water 100 gal, fuel, provisions for several people,and several passengers. Although there isn't any current the waves can add the extra drag, typically 2'-3' on a calm day. It's about 200 miles round trip and I can do it on (340 gal). Cruise speed of 18-19mph around 3K-rpm (About .6 miles/gal). You'd probably be cutting it close. Also if you run generator and condition of engines your milage may vary.
Going slow and freewheeling one engine would extend your milage for sure. I typicaly use one engine once I leave the slip cruising down the river (1100-2000rpm max.) because it takes 45 minutes to get to the big lake, saves on engine run time and fuel consumption over time. Boat handles fine on one engine.

 

[Nick Hahn]

So the admiral wants to take a little trip to her parents house this coming weekend, a trip down the Ohio river. There is one set of locks (McAlpine) along the way, but NO fuel stations. The trip is about 50 nautical miles one way, maybe an extra 20 miles spent entertaining while we're there. It's downriver to get there, upriver to get home. Our boat is named "Lollygagging" for a reason...I don't mind running slow LOL

Being conservative, can I realistically (easily) make a 100-150 mile round trip down and back up the river, or would I possibly not have enough fuel even if I stay out of the throttles?

I have the usual 150 gallon tanks for each side. I've looked up the Mercruiser charts on theoretical burn rate for my gas 7.4's with 2-barrel carbs at different RPM's, but with no flow meters I haven't calculated with my specific 400EC how far she goes per gallon, at what speed or RPM is her "sweet spot" for burning efficiency. I won't have the opportunity to do any real world calculations before we go, so I'm just asking for opinions based on "your experience with your 400EC"....

Thanks!

We did a 90 mile cruise - Holland to St Joseph a couple of weekends ago - got about 0.5 mile per gallon. Mostly running 2900 - 3000 rpm. 120 mile trip should not be a problem, pushing it to 150 could result in some unnecessary stress watching the fuel gauges on the way home.

 

[h_gerry]

I removed the starboard side helm seat for new upholstery and found that there is a seat adjustment lever on the right side of the seat for forward, and rearward adjustment, and the left side has a broken off stud in the rail. Can anyone tell me if where I found the broken stud there should be a Tee handle that would lock down the left side of the seat after a seat adjustment was made?

I don't believe my helm seat has a lock down on it. The slide adjustment on the right side has notches to keep the seat in one of several fixed positions.

 

[Mikentucky]

We did a 90 mile cruise - Holland to St Joseph a couple of weekends ago - got about 0.5 mile per gallon. Mostly running 2900 - 3000 rpm. 120 mile trip should not be a problem, pushing it to 150 could result in some unnecessary stress watching the fuel gauges on the way home.

Is that .5mpg on each engine (from each tank), or was your calculation based on "we did a 90 mile trip and it took 180 gallons to refill the tanks"? If that's per engine, and with my 150 gallon tanks, that equates to about a 75 mile range Or that's per engine but you only ran on one engine at times to get the 90 miles there and back on a single fill up?

 

[Nick Hahn]

Is that .5mpg on each engine (from each tank), or was your calculation based on "we did a 90 mile trip and it took 180 gallons to refill the tanks"? If that's per engine, and with my 150 gallon tanks, that equates to about a 75 mile range Or that's per engine but you only ran on one engine at times to get the 90 miles there and back on a single fill up?

Based on we did a 90 mile trip and used 180 gallon to fill up. I always run on both engines.

 

[Mikentucky]

Based on we did a 90 mile trip and used 180 gallon to fill up. I always run on both engines.

AWESOME! Thanks, makes me feel a lot better about our trip. For the downriver portion I plan on staying about 2k and 15mph, just relaxing and enjoying the ride (about a 3 hour trip give or take, depending on time spent getting through the locks). Thanks again for the input!

 

[h_gerry]

Is that .5mpg on each engine (from each tank), or was your calculation based on "we did a 90 mile trip and it took 180 gallons to refill the tanks"? If that's per engine, and with my 150 gallon tanks, that equates to about a 75 mile range Or that's per engine but you only ran on one engine at times to get the 90 miles there and back on a single fill up?

Using numbers from a recent trip I took, I am burning about 22 gallons per hour overall with generator running. This is based on filling the tanks with 198.5 total gallons (93.5 port, 105 starboard) after 9 hours of engine run time. The trip was a mix of on plane and no wake zones (5-6 mph) of approximately 130 st. miles. Roughly .65 mpg overall. I am normally running on plane at 3300-3400 rpms making 19-21 mph.

 

[TALON]

I don't believe my helm seat has a lock down on it. The slide adjustment on the right side has notches to keep the seat in one of several fixed positions.

Thanks for the input.
Ken

 

[Air O'Nautical]

I cringe at discussing miles per gallon...
Having not ever really nailed it down, I can certainly tell the more RPM you run the more fuel you’ll burn.
A gasoline powered 400EC doesn’t really have a sweet spot on plane like a ski-boat does.
Once did a family vacation 90 miles away from home @5-6kts out and returned home two weeks later @24kts.
Used less than 1/4 out (refueled on arrival) and 3/4++ coming back!
Fuel flow meters with a GPS speed input calculation for instantaneous MPG is the only real way to know.
I almost installed FloScan tachometer/ flow meters to get this information but, never have..I might if I ever want to travel over 100 miles in one leg.
Water/weather conditions, time available, maintenance status, crew morale all dictate my cruise speed

 

[GregM]

I cringe at discussing miles per gallon...
Having not ever really nailed it down, I can certainly tell the more RPM you run the more fuel you’ll burn.
A gasoline powered 400EC doesn’t really have a sweet spot on plane like a ski-boat does.
Once did a family vacation 90 miles away from home @5-6kts out and returned home two weeks later @24kts.
Used less than 1/4 out (refueled on arrival) and 3/4++ coming back!
Fuel flow meters with a GPS speed input calculation for instantaneous MPG is the only real way to know.
I almost installed FloScan tachometer/ flow meters to get this information but, never have..I might if I ever want to travel over 100 miles in one leg.
Water/weather conditions, time available, maintenance status, crew morale all dictate my cruise speed

Let's just hope they NEVER put a "Gas Guzzler" tax on boats, lol....That's why I stated previously whenever I can I only use one engine. The boat handles well on one if you're idling down the river and it reduces engine wear, fuel consumption, and even emmisions. Many marina's on the west coast of Michigan are some 45 min to an hour away from the big lake, hell my friends boat is an 1hr 45min from big lake. These rivers are all no wake zones. That equates to a considerable amount of reduced engine time and fuel burn in a year.

 

[sws01]

I installed the one that came today--not an exact match. The color is more white than the off-white of the boat, and the opening is slightly different...but the three push-pin holes match up, and it covers the open vent hole. It'll work for now

Well, I closed on the boat and tried to install the clamshell, but the christmas-tree fasteners, although they aligned with the holes, would not go in. Even after some less than gentle persuasion with a hammer!!. I think it might be that the old fasteners might have broken off and are still in the holes.

How do you access this location from inside the boat? Is that necessary? There seems to be some sort of flexible duct that vents out the clamshell - anybody know what is it and how to access it? I don't want to tear anything up, but having a 3" hole in the hullside of the boat is not a good plan.

Thanks for any help anyone can provide.

 

[Mikentucky]

Well, I closed on the boat and tried to install the clamshell, but the christmas-tree fasteners, although they aligned with the holes, would not go in. Even after some less than gentle persuasion with a hammer!!. I think it might be that the old fasteners might have broken off and are still in the holes.

How do you access this location from inside the boat? Is that necessary? There seems to be some sort of flexible duct that vents out the clamshell - anybody know what is it and how to access it? I don't want to tear anything up, but having a 3" hole in the hullside of the boat is not a good plan.

Thanks for any help anyone can provide.

You were correct---it's most likely the old fasteners broken off inside of the holes. When these vent covers come off, it's usually because it gets "ripped" off by something (another boat's fender during raft-up, mooring post, etc.)

All three of mine were sheared off and still in the holes. I tried to dig them out with picks, needlenose pliers...no luck, besides being a pressure-fit part, the originals are put in with silicone. I ended up getting a drill bit slightly larger than the core of the Christmas tree and drilling into the old ones, then putting some silicone on the new ones as I hammered it in with a rubber mallet. Quick tip--eyeball the drill bit up against the Christmas tree, and wrap a piece of electrical tape around the bit to mark how deep you need to drill. That way you drill deep enough to fully seat the Christmas tree, without accidentally drilling all the way through the hull.

 

[TALON]

As stated earlier I removed the helm seat for some upholstery updating...



...and found this...



...not very happy!

 

[Nick Hahn]

Is the seat base fiberglass or something else? Fiberglass can be repaired I was given an article on repairing a Sea Ray fiberglass seat. I'm sure my passenger seat needs repaired. . .

 

[TALON]

Is the seat base fiberglass or something else? Fiberglass can be repaired I was given an article on repairing a Sea Ray fiberglass seat. I'm sure my passenger seat needs repaired. . .

Definitely not fiberglass, some sort of 1/8" thick plastic. After stapling we applied 2 part epoxy, and a few mending plates. Hope this holds.