1991 Wellcraft Eclipse wont reach WOT

[bishop1976]

The boat is a 1991 Wellcraft Eclipse 232 powered by a MCM 350 Magnum. The engine plate says WOT should be between 4200 and 4600 RPM's.When out on the lake this weekend the boat ran well at idle and never gave any indication of poor throttle response up and to WOT. The problem is that I could never get above 3500 RPM's at WOT and the boat felt as if it were bogging and coming off plane in even the slightest of turns. From my past experience it seemed that the engine was lugging or under a heavy load like maybe too much prop but from everything I can find online the 14 1/2 x 17 RH stainless prop on the boat is close to the right prop. I have trim tabs on this boat and they seemed to keep the boat on plane in straight travel. The lower unit is an alpha 1 and I just had it serviced at the dealer. Anyone have any ideas what this could be? Opinions on the correct prop etc. Max speed on GPS was 29 MPH. Hardly the speed I expected.

 

[danond]

Re: 1991 Wellcraft Eclipse wont reach WOT

Common question. Many times it can be a plugged fuel pickup.

It could also be that your boat's been soaked with water and the foam underneath is water logged, weighing you down. Did it get rained in?

 

[bishop1976]

Re: 1991 Wellcraft Eclipse wont reach WOT

Fuel system is clean as far as I can tell. It's getting plenty of gas.

Hasn't been rained in and was kept in covered storage by the owner before me. Just out of curiosity though how do you check wet foam and how do you remedy that?

 

[MikDee]

Re: 1991 Wellcraft Eclipse wont reach WOT

Your prop size sounds just about right.

1) is your throttle, & carburetor, opening all the way?
2) is your flame arrestor clean, & free flowing?
3) is your fuel tank vent, venting? try blowing into it from the outside, or (take off the cap temp during a run)
4) Check to see if your spark plug wiring is right (it is clockwise rotation on the Dist.) and the firing order is embossed on the manifold 1-8-4-3-6-5-7-2
5) Check to see if your spark advance is working
6) Finally check out all gas filters, including the one in the carb itself, And the antisiphon valve, & fuel screen in the gas tank

These are a few items to start with, Your boat should do 40mph plus if all was well

 

[SuperDaddy]

Re: 1991 Wellcraft Eclipse wont reach WOT

The boat is a 1991 Wellcraft Eclipse 232 powered by a MCM 350 Magnum. The engine plate says WOT should be between 4200 and 4600 RPM's.When out on the lake this weekend the boat ran well at idle and never gave any indication of poor throttle response up and to WOT. The problem is that I could never get above 3500 RPM's at WOT and the boat felt as if it were bogging and coming off plane in even the slightest of turns. From my past experience it seemed that the engine was lugging or under a heavy load like maybe too much prop but from everything I can find online the 14 1/2 x 17 RH stainless prop on the boat is close to the right prop. I have trim tabs on this boat and they seemed to keep the boat on plane in straight travel. The lower unit is an alpha 1 and I just had it serviced at the dealer. Anyone have any ideas what this could be? Opinions on the correct prop etc. Max speed on GPS was 29 MPH. Hardly the speed I expected.

I have a 1990 Wellcraft Eclipse 233 with the same engine, so it's nearly the same boat.

But, I use a 14 1/2 x 19 prop. My cruising RPM's, WOT RPM's, cruising speed, etc are all in line with what I should be getting.

I wonder if you have the wrong prop on yours. Not certain, though.

 

[bruceb58]

Re: 1991 Wellcraft Eclipse wont reach WOT

Was it working before you took it to the dealer or is this a recurring problem?

That boat does not have the foam in the hull like Danund was talking about so that won't be a problem.

 

[Bondo]

Re: 1991 Wellcraft Eclipse wont reach WOT

Ayuh,... Up in the Adults Only section, Don has the list of things that will cause the loss of rpms at WOT...

 

[wil7483]

Re: 1991 Wellcraft Eclipse wont reach WOT

Was it working before you took it to the dealer or is this a recurring problem?

That boat does not have the foam in the hull like Danund was talking about so that won't be a problem.

I was about to say the same thing. That boat doesn't have any foam in it. I have a similar problem with a 1988 Wellcraft Elite. I am turning a 17p prop and can get 4300 rpm at WOT but I'm sure that I should be able to turn a 19p at 4400 rpm easily. I have checked the carb/fuel system, adjusted the rocker arms/lifters, experimented with different props, etc. The only thing left is to adjust the carb's fuel/air mixture and see if it has any noticeable effect. I can get to 40 mph though so I'm not overly bothered by the WOT numbers but it would be nice to get it to run at it's best under every situation.

Keep experimenting and making adjustments and you should be able to find the problem.

 

[bishop1976]

Re: 1991 Wellcraft Eclipse wont reach WOT

So if there is no foam in the boat then I dont need to do any destructive investigating. The boat felt really heavy though. A couple of cups of water drained from the plug when I removed it but no more than usual with kids in and out of the boat. The engine really felt like she was under an extreme load...turning was a little nerving.

I'll look for the list of usual suspects in the Adult only section and try your recomendations. Could I be overpropped?

 

[bishop1976]

Re: 1991 Wellcraft Eclipse wont reach WOT

I thoguht I would add that the engine seemed to perform very well. No missing or hesitations. I'm stumped.

 

[bruceb58]

Re: 1991 Wellcraft Eclipse wont reach WOT

Is all of this something new? Have you owned this boat a long time and this is new behavior for it?

 

[bishop1976]

Re: 1991 Wellcraft Eclipse wont reach WOT

No Gene I bought it in December but I've run it alot on muffs and in a barrel.
Runs very good at idle...quick starts, and under a load. Just seems to be under a huge load. The previous owner was very honest with me about all other issues. He said he never had any of these problmes and the service tech tested everything ok in the tank. I'm thinking of doing a complete tune-up, going throguht the fuel system checks, and maybe a 19 pitch prop...see where that leaves me.

 

[bruceb58]

Re: 1991 Wellcraft Eclipse wont reach WOT

If you haven't gone through a whole tune-up yet, that is definitely your first step. I would also do a compression check just for sanity sake and it also gives you a baseline for future to compare these to. Make sure you write these down for future reference.

Like Bondo said, go up to the sticky and do all the tests there.

How old is the gas in the boat?

 

[bishop1976]

Re: 1991 Wellcraft Eclipse wont reach WOT

I agree. the boat had about a quarter tank or maybe a littel more. I put in 50 gallons befroe launching the other day. It didnt use near as much gas as I expected it to. It did have stabil and I added a bottle of heet several weeks ago in case there was any water in the fuel.

 

[wil7483]

Re: 1991 Wellcraft Eclipse wont reach WOT

.......and maybe a 19 pitch prop...see where that leaves me.

If you think that you are overpropped then why would you go up in diameter to a 19p? If you are overpropped then you need to be dropping down to a 15p or 13p. From the numbers that you posted earlier I doubt that it's a prop issue. I can tell you that if you do go to a 19p that your numbers will be even worse than they are now. If your engine can't spin that 17p then there is no way it is going to spin a 19p.

 

[bishop1976]

Re: 1991 Wellcraft Eclipse wont reach WOT

I meant a prop with a lower pitch. Sorry.

 

[bruceb58]

Re: 1991 Wellcraft Eclipse wont reach WOT

If you think that you are overpropped then why would you go up in diameter to a 19p?.

Just to clarify...should not be diameter but pitch.

 

[wil7483]

Re: 1991 Wellcraft Eclipse wont reach WOT

I stand corrected. Mistyped that's all.

 

[bishop1976]

Re: 1991 Wellcraft Eclipse wont reach WOT

I dont have a parts list for this motor yet. Can anyone tell me which distributor cap and button goes on a MCM 350 MAgnum Serial OD503525?

I'm going to put on new plugs, cap and button. Maybe wires but they all look good. Any recommedations on something I may have overlooked for a tuneup?

 

[bishop1976]

Re: 1991 Wellcraft Eclipse wont reach WOT

anyone?