My first boat; 2001 1800SR

[mikealan]

Hi everybody,
My name is Mike, and recently bought this pretty nice, used 1800SR. I don't know a lot about it, or any other boats for that matter. Lucky for me, my brother used to have the same model/year Maxum, because the owners of the aircraft carriers I was deployed to years ago wouldn't let me drive them and offered no training. Their reasoning was, that I was on board to work on the F-14s and not the ship itself. The nerve.

As for the 1800SR- I have the manuals for it, and plan to learn a lot, if all the standard boat "jokes" I've been deluged with are true.

So far we've taken her to the lake twice, and it's been a blast. Since she is nowhere near new; I anticipate having at least some issues. I hope that isn't a gross understatement.

I have spent a few hours just reading through some topics and posts here, to get a feel for your website. I appreciate the literature section as well.

I will now go forth and display my ignorance for all to see, by posting a question about the engine performance. Thanks for being here,
Mike

[mmwjr]

Mike welcome aboard

Post some pictures of your new toy.

What is your question regarding engine performance and what engine do you have?

[mikealan]

Originally Posted by mmwjr

Mike welcome aboard

Post some pictures of your new toy.

What is your question regarding engine performance and what engine do you have?

Thanks Mike,
I haven't taken any pics yet, but this weekend I will, and post them.
It's MerCruiser 4.3 liter v6 with 2 barrel carb, About 200 hours. It runs great until you reach wide open throttle, where the tach reads about 4800 rpm. At wide open, it begins to make a popping sound, sounds like from the exhaust but not sure. As soon as you back off the throttle just a tiny amount, it runs great again.
I had thought could be bad plug(s), wires or cracked cap or rotor. After replacing plugs, wires, cap and rotor, as well as the spin-on water trapping fuel filter, it has not changed.
I just now became aware that there is a gas filter in line with the fuel inlet line on the carb...I will change that asap.
Any suggestions would be great!
Thanks in advance.

[mmwjr]

Sounds like you are hitting the rev limiter threshold that is there to protect the engine from over revving. You should not run at WOT for more than a few minutes anyway as it is not designed to run under load for extended periods at this rpm. Cruising rpm is typically no higher than 4000 rpm.

[mikealan]

Originally Posted by mmwjr

Sounds like you are hitting the rev limiter threshold that is there to protect the engine from over revving. You should not run at WOT for more than a few minutes anyway as it is not designed to run under load for extended periods at this rpm. Cruising rpm is typically no higher than 4000 rpm.

Thanks Mike,
I appreciate your reply.
I was told by the PO that's what the repair shop had told him when he took it in for a checkup before selling it to me. I wanted to double check since I have no receipts or any proof from them.

I do understand it's not good to run an engine at WOT for extended periods, it's just a thing we did only for a few seconds, curious to see if it was really happening, and what may be the reason for it, as a part of the test drive prior to purchase.

The thing is not like the rev limiters we've had experience with on car engines. This one seems pretty "random" in the way it works. The pop sound is not consistent in tone or volume or frequency. It really sounds more like the often random sound of arcing plug wires.

I'm not disagreeing with you...just asking if they are normally like this? I'm asking because my brother's 1800SR he bought new in 2001 (identically equipped to the 2001 1800SR I just bought used) did not operate in this manner. If it had a rev limiter, it did not make itself obvious in any way.
Was that an exception?

Is there any sort of standard way of dealing with this that other owners have?
Can the throttle components be adjusted to limit the WOT rpm, rather than allowing RPM to reach the limiter?
It's not that I want to blow it up, obviously, but being a guy who appreciates performance, the occasional urge to just let it rip is bound to happen. Not for all day, but just a few seconds once in a great while.

Another thought: it seems somebody changed the prop at some point. I'm thinking if I replaced the prop for a one degree more, It could keep the same top speed while holding the RPMs down below the limiter point. Does that seem like an idea worth trying?

Thanks again for your time, and sharing your knowledge.
Mike

[mmwjr]

Mike you hit it at the end, this engine should have a WOT of 4600 - 4800. If you increase the props pitch one up from the current prop you should drop the rpm to the correct spec.

I cannot explain the difference between the two boats. Yours may also have a valve that is starting to float (not returning to full closed) at this over revved rpm.

[mikealan]

Originally Posted by mmwjr

Mike you hit it at the end, this engine should have a WOT of 4600 - 4800. If you increase the props pitch one up from the current prop you should drop the rpm to the correct spec.

I cannot explain the difference between the two boats. Yours may also have a valve that is starting to float (not returning to full closed) at this over revved rpm.

Mike,
Thanks again for your time and knowledge. It's very helpful and I certainly appreciate it.
I have a feeling I will learn a lot from you and others here.
So, now when I have anymore questions, I should put those in the appropriate sub-forum, correct?

[mmwjr]

Correct and I am sure you will provide valuable info to the site as well.

I'm just a fellow boater who is an old gear head but far from a expert, just enjoy troubleshooting issue expecially when they are not mine.

[mikealan]

Hi mmwjr,
Picture, as requested...
Mike

[mmwjr]

Hi Mike you can call me Mike as well.

Nice looking boat, what is that picture on the bow looks like a duck.

[mikealan]

Originally Posted by mmwjr

Hi Mike you can call me Mike as well.

Nice looking boat, what is that picture on the bow looks like a duck.

Close, it's a goose, and thanks for noticing!
People from the Chicago area might remember a very popular kid's TV show, Garfield Goose & Friends, which aired from 1955 to 1976.
It was a puppet show, and Garfield Goose was the main character, as self-proclaimed "King of the United States". It was the longest running puppet type show, if I recall.
I make reproductions of the puppet, so as a kind of a joke suggested by my friends, who wanted to name the boat after the puppet.
Thanks Mike!

[Timbo]

Welcome aboard Mike, looks like you did well on your first boat. Enjoy.

[mmwjr]

Originally Posted by mikealan

Close, it's a goose, and thanks for noticing!
People from the Chicago area might remember a very popular kid's TV show, Garfield Goose & Friends, which aired from 1955 to 1976.
It was a puppet show, and Garfield Goose was the main character, as self-proclaimed "King of the United States". It was the longest running puppet type show, if I recall.
I make reproductions of the puppet, so as a kind of a joke suggested by my friends, who wanted to name the boat after the puppet.
Thanks Mike!

Now I am hearing that old child saying; Duck, Duck, Goose

[mikealan]

Originally Posted by Timbo

Welcome aboard Mike, looks like you did well on your first boat. Enjoy.

Thanks for the kind welcome!
We've had her out 4 times now, and have had zero (knocking on wood) problems with the boat performance. Of course, my main use of the boat is to simply get me and my family/friends from the launch to an isolated, sandy beach somewhere on the lake, where we spend as much time as possible standing up to our necks in cool, refreshing water while drinking lots and lots of...water? Nope. Beer.
I can see where the "boat" jokes could get a start, though.
Lucky for me I was able to locate the manuals here, which I am very grateful for, and also lucky that I have always been a mechanic of some sort. Not an expert at anything anymore, but can figure out how to fix almost anything. The internet is really great for info on that stuff.
I have had to replace almost the entire braking system, except drums, including the small surge actuator and master cylinder on the trailer, and replaced all the lines with those new-fangled kind of vinyl ones that flex easily.
Replaced the main running/brake/turning signal lights, and wiring also just to be sure, since they showed OK while sitting still but had intermittent problems while running down the road. After removing & replacing all the old wiring I was glad I did it. There must have been 50 splices altogether, lots of patched together stuff, and not many were well sealed. The new LED lights are brighter and hopefully more reliable than the original. I used marine grade heat shrink connectors and liberal amounts of liquid electrical tape on all connections.
On the boat itself, there's only been a few minor issues that were there when I bought it, and they are all fixed now.
Speedometer not working...simple fix, once I was able to locate the information - which was surprisingly hard to do, for some reason. Is it just me, or does google seem less effective these days?
Anyway, I just got down on the ground under the back - uh, I meant to say stern, and plugged in the connector underneath the drive. Apparently the mechs forgot to plug it back in when the PO had some work done a few months ago, just prior to me buying it.
Fuel gauge...showed no reading or a random reading at times. It was the sending unit. The outside of it is black plastic and showed zero damage or wear, so I took it apart out of curiosity, and man that thing was corroded on the inside. Not too badly priced at $55 for an OEM from Amazon. For anybody who has similar problem, the correct length for the fuel sending unit on a 2001 1800SR is 6.5".
Only other thing is the rev limiter, which isn't really a problem but an annoyance, as Mike here told me it could be overcome by replacing the prop with the stock pitch, or one at least closer to it.
I don't know where I saw it, but I think somebody here said the stock pitch is 23, and the boat has a 19 on it now. Top speed now is about 40 at 4800 rpm. I think the stock pitch would put top speed at closer to 50 or maybe a bit more, does that seem right?
Thanks again for all your help and warm welcome.

[mikealan]

Just to wrap this up,
The solution to the engine popping when at or near WOT was (as Mike suggested) to install a 14"x23 pitch propeller, which is what this boat supposedly came with.
WOT is still about 4800 RPM or a bit higher, and the new top speed is up from around 40 to around 50 MPH, and any signs of rev-limiting popping are gone.
Surprising, for me, is that no other aspect of the boat performance has suffered.
A win-win.
Thanks Mike and everybody who helps here!