Mercury 20-HP FOURSTROKE Stalls

[davidc]

I have a 1968 13 Sport that always had a 40-HP two-stroke-power-cycle outboard engine with short shaft. I installed a new Mercury 20-HP FOURSTROKE short-shaft engine with power trim and a new steering system. I am no longer tubing and felt the 20-HP would be fast enough and give me great fuel consumption.

There is an exhaust port near the top of the shaft, just under the cowling. When running at slower speeds the water enters the exhaust port and shuts the motor down. It runs fine at full throttle and most of the time in slower speeds. I tried tilting the motor at slower speeds--which also helps somewhat--but performance and general steering is terrible.

I am alone on the boat so most of the weight is in the back which doesn't help.

The dealer suggested adding weight to the front--easier said then done. I don't want lead weights smashing down on the deck.

The motor runs fine with someone sitting up on the bow. In 20 hours or so its stalled about 18 times.

Any suggestions??

[Jefecinco]

Perhaps the engine is mounted lower than necessary? If your battery and/or fuel tank are mounted under or behind the aft thwart consider relocating it/them forward as much as practicable. I mounted our six gallon fuel tank under the forward thwart but the battery remains aft. Our 13 has a 30 HP Mercury four stroke with tilt and trim and we have no difficulties with water interfering with the exhaust although I believe all of our exhaust exits through the propeller.

[matt13moto]

My recommendation would be to try a doll fin mounted on the citation plate. I know it sounds cheesy, but for 50 bucks its worth a shot they work quite well for slow speed planing and help keep the bow down on take off.

[jimh]

Do you really have a 15-inch engine with power trim and it's a four-stroke?

[davidc]

Yes,it's a four stroke 15" shaft with power tilt
They raised it up as far as they can and it still stalls

[davidc]

The exhaust port is taking in water and stalling the motor. The dealer didn't know [how to solve the problem]. I called Mercury; they didn't know what the problem was. They said it is the dealer's problem to solve. I called Tohutsu for advise and they identified the problem on the phone.

I've called Mercury multiple times asking for a manager and their answer is none are available. They have a poor corporate culture there. They could care less.

I bought a Yamaha for my sailboat and two years later they are still sending me surveys to make sure I'm happy.

[jimh]

Do you want to continue to discuss a repair to your engine, or are you just interested in bashing the manufacturer about post sale free telephone support?

[davidc]

Just trying to warn others,including you.
If I knew what mercury corporate was like I'd never have bought one.
Do you work for them?????

[jimh]

Please find a new website to post your views on corporate cultures. Continuouswave is interested in information about boating.

Mercury is not a corporation. It is just a brand of Brunswick.

[Jefecinco]

David,

You've had some suggestions. Have you discounted them or have you tried other solutions of your engine problem? I believe the root cause of your troubles was your selection of a 20 HP engine for your boat. There is not a lot you can do to compensate for an under powered boat. To expect Mercury to troubleshoot your problem over the telephone is unrealistic. Mercury has dealers to sell and service it's products. Some are imperfect but they are your source and on the plus side there are a lot of them.

Perhaps a Boston Whaler dealer can offer you some advice.

[jimh]

By the way, to ask me if I work for Mercury has to be perhaps the most naive question I've ever fielded on this forum. I am not in the employ of any boating-related company. If I were, I would have disclosed that and made it completely transparent.

There is nothing in your narrative about your engine problems that constitutes a situation that others ought to be warned about, except perhaps your expectations of obtaining free remedies to problems that are not related to any defect in original manufacture from first tier customer service agents of the manufacturer.

[davidc]

I have moved my gas tank,storage box and anchor forward with limited results.They also raised the motor up 3/4".May have to raise it up more.
A 20hp is not really under powered.It may be for many people wanting to ski ,tube,or others that may carry multiple adults,but for someone just cruising its ok.I also checked this with Boston Whaler before the purchase.
As far as calling Mercury for free advise.I spent over $6,000.000 on this(including new steering)
I only purchased it 8 weeks ago and its obviously still under warranty.I don't consider calling Mercury because Im dissatisfied with their dealer asking for free advise.If someone was representing me poorly,Id want to know.They don't.
I agree theres not alot they can do but they should have tried.To give you an example.
I called Tohutsu and Honda.They BOTH gave me good advise over the phone.Why can they and not Mercury?????In fact,Honda hooked me up with a guy that owns the same 20hp(but Honda brand)who is having no problems on the exact same boat.Him and his friend sit in the back of the boat.
With all due respect guys,our automotive industry in the 70"s had the same attitude as Mercury.Look what happened to them.

[Jefecinco]

I'm glad to read that you've had some improvement. A hydrofoil mounted to the engine anticavitation plate could possibly get you to the level of satisfaction you're seeking. They are relatively inexpensive. I've probably overlooked it but I don't recall anything in this discussion about propeller choices. Where are you with that?

[pederj]

I have a similair setup. Mine is a 1969 13' with a 2009 Mercury fourstroke. Mine has never stalled at any speed, running with 1-4 people. I do a lot of trolling also. My motor is mounted all the way down with a 10P mercury alluminum prop. I would think our motors are basically the same.

There must be more to it.