Official 400EC thread

Re: Official 400EC thread best cruise/fuel burn

Searaybio270 said:
Expressboy - did the Flo scan's come with the boat or did you have them put on? I agree on the speed but getting mine on plane seem a bit iffy at times. I just took a ride in my friends 38DA 2008. We were way out of the water at the swim platform area. My boat tends to keep the swim platform in the water. Doesn't appear to lift the butt out of the water. Does your boat do that or is it lifting?
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Wow... that isnt anything like the way mine performs. Last week I had five adults on board, full water and fuel, enough beer and groceries to keep us happy for four days.. I had my 11'zodiac with my 15hp outboard on my swim platform davits.. and I had my 13' RIB zodiac with a 30hp outboard in tow... and it still came up on plane with no issues by just advancing the throttles up to 3100 rpm. The swim platform is definitely not dragging in the water. I didnt really expect the boat to perform this well ( except for the use of fuel ). With a little less fuel and no avon in tow it pretty well jumps up to speed even in 30kts. of wind and wave on the bow on the river. The next time I am on the boat I will video the take off and send it to you for you to compare performance

The previous owner did the floscan, I use tabs to keep the bow down on launch.
Thanks
EXPRESSBOY
 
Re: Official 400EC thread best cruise/fuel burn

Well, based on that I may have something wrong. Even at 3200 to 3400 I am still butt dragging. Now I usually have full fuel, 1/2 water and the Admiral (she's not that heavy). I do have a very large cooler on the back but I can't imaging that is why it won't come up out of the water.
May in a few minutes I''ll know what is wrong when the mechanic calls about the port engine. Initial call said he found some water in #5 spark plug jacket. Can't wait to see what this is going to cost me.
 
Re: Official 400EC thread best cruise/fuel burn

Searaybio270 said:
Well, based on that I may have something wrong. Even at 3200 to 3400 I am still butt dragging. Now I usually have full fuel, 1/2 water and the Admiral (she's not that heavy). I do have a very large cooler on the back but I can't imaging that is why it won't come up out of the water.
May in a few minutes I''ll know what is wrong when the mechanic calls about the port engine. Initial call said he found some water in #5 spark plug jacket. Can't wait to see what this is going to cost me.
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I can't recall if rusted or failed exhaust risers and gaskets can contribute to that or not. But if they can and need to be replaced do it yourself. It's an EASY job that marinas often charge too much for.

Good luck!
 
The 400EC is a quick and nimble boat that shouldn't be at all stern heavy. If y'all have one that is, then you need to do some investigation to discover the reason.

It isn't a sweet spot, but 3200 rpms is kind of a magic number for 454's, particularly with older carbureted engines. Beyond that, you need to keep up with fuel dock locations because you are going to need them.

Corrosion in risers and manifolds can definitely affect performance. In fact, lost performance is a very good early warning of impending problems. The internal passages on the risers, first, then the manifolds, will bubble up and nearly close off with corrosion and that seriously affects the way a big bore motor breathes particularly as it reaches its peak power output, which is where you guys are talking about running them. Very soon after you get enough corrosion build up in the risers to feel lower performance, you will get water in a cylinder or 2 since the casting walls are thin enough to break thru.
 
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I had a ’92 400 EC with the gassers. I found the optimum RPM to be right around 3200 as many have said. This provided just shy of a .7 mpg with tabs down slightly. I never had issues getting it up on plane (plenty of power), but the swim platform did have water that “slightly ran over” over the 2 outside corners when running at that speed. Never could get or saw much better than that. Have fun.
 
fwebster said:
The 400EC is a quick and nimble boat that shouldn't be at all stern heavy. If y'all have one that is, then you need to do some investigation to discover the reason.

It isn't a sweet spot, but 3200 rpms is kind of a magic number for 454's, particularly with older carbureted engines. Beyond that, you need to keep up with fuel dock locations because you are going to need them.

Corrosion in risers and manifolds can definitely affect performance. In fact, lost performance is a very good early warning of impending problems. The internal passages on the risers, first, then the manifolds, will bubble up and nearly close off with corrosion and that seriously affects the way a big bore motor breathes particularly as it reaches its peak power output, which is where you guys are talking about running them. Very soon after you get enough corrosion build up in the risers to feel lower performance, you will get water in a cylinder or 2 since the casting walls are thin enough to break thru.
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Frank,
Thanks for the info. Compression check showed 55PSI on number 5 and 135 on number 4. Heads are being pulled and injectors are being sent off for cleaning. The PO replaced the risers/manifolds prior to the sale so I hope it isn't that. I too believe around 3200RPM is the magic number, well some number not sure if it is magic or not. But she usually runs rather well at that speed and handles quite easily. So, no boating for ten days or so. Plus I now have to tell the Admiral no trip to Baltimore Friday night with friends. No dinner at Fogo de Chao. No raft up at Still Pond. Maybe I'll go play golf on Saturday but leave Friday night.
Thanks everyone - I'll keep you posted. Unless she kills me!!!
 
copb8tx - Thanks. In a way I am ok that they found this now. My plans are to leave the boat in the water all winter. Maybe this is a blessing.
 
douglee25 said:
What exactly are the issues?
Rocker arms broken. Connecting rod broken. injectors are plugged - being cleaned. needs exhaust manifolds and risers. Two alternators. IAC Value (?). Heads are out to be checked and quite possibly replaced. etc etc etc.

Doug
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copb8tx said:
Yikes! Anything you can do yourself to minimize the charges?
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I would attempt to do some of it but I am so busy from 5am until 9pm seven days a week. I tried several mechanics, including mine, everyone busy for at least two weeks. Even some of the guys I know from the boat club are busy with families, boating and the fiscal year ends in Sept - so no luck there. I am sure I will have to do the starboard engine. I will plan to do that this coming fall/winter or early spring. Depends what the compression check looks like.
 
If you had a connecting rod broken, you were have heard some louding knocking going on? Are you sure this is correct?

Are they giving you a whole new long block?

Doug
 
I had a tapping noise right after I launched in May/June. My mechanic listen and he thought it was a valve tapping or something like that. He said take it out and get it up on plane and it should go away. And it did. Never a loud knocking noise, ever. Actually, once I took the boat out and the tapping noise stopped both engines from that point on sounded great. I will say I couldn't get the butt end of the boat out of the water yet she would run fine and at a good clip 23 to 25MPH at 3200. Start first time every time. Never a knocking.
Yes, I am getting a long block.
 
My only advice is be careful with who you're dealing with. I'm not saying they aren't doing the right thing, but larger shops like MM are known to be parts changers vs. actually fixing the problem *at times*. It's easier for them to swap your engine out vs. fixing it which may be cheaper on your wallet. So when you said a broken rod, my eyebrows raised because there is no way you would get up to that rpm with a broken rod. Bent maybe, but not broken. It sounds like you're already at their mercy because your boat is blocked at their yard, but again be careful.

Doug
 
I did see, for what it is worth, the rocker arms. The where broken and that happened quite some time ago according to them. I have asked for all the parts to include the risers and manifolds.
 
Does anybody have a wiring diagram of their 400EC ?... I am trying to figure out a couple wiring issues and a schematic would sure help!

Thanks All,
EXPRESSBOY
 
There is no one wire diagram but sea ray customer service can provide the information for what you need specific to area in question
 
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AC question: I have two units on my boat. The one in the forward berth isn't pumping out water. I checked the line from the unit to the through hull. It is clean. So I disconnected the discharge hose and turned the unit on. No water was flowing through the system.
Here in lies the question: Is there one or two sources of water coming into the boat? Ie., one for each AC. There is one I found in the engine compartment and it is on and running the salon AC.
Ok - Brain picking time - Thanks guys Joe
 
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