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1999 5.7 rpm

Re: 99 5.7 rpm

Thanks, that wasn't so hard.
I do have to find out the rest of that to however. Never seen it run up to 4200 even, normally 4000 max, 38-3900 flat out. Tach isn't the most accurate from time to time.
Seems like it could be over proped. Runs a bravo 3 I assume the pitch is ID'ed somewhere on them.
 
Re: 99 5.7 rpm

Try trimming the outdrive up and see if your rpms increase..............

Just saying...........
 
Re: 99 5.7 rpm

Well I did get a repair manual, for a few maint. tips & such. Glanced through it last night, doesn't give anything for running spec's (Good book!)
Merc# UL ur OL208466 has a Bravo 3 With prop's 48-823665 a6 24p & 668 a6 26p
Its in a 28'rinker cabin cruiser (Sorry my Scale is on the Fritz, couldn't wiegh it)
Had a 2barrel Merc. carb. As I said seems doggy on lower end & on plane does, ok but never a real consistant speed with the same load & wind conditions. Let me know if anything else helps.
 
Re: 99 5.7 rpm

Several things

1. too big a boat for a 5.7 and a two barrel carb.
2. no matter what the power package the motor should reach propper rpms, 4400-4800 rpms. 90% of the time it is due to proppeler pitch. With a bravo three that is expensive to change.
3. You never answered my question, did you tim the outdrive up as far as possible before cavitation????????????
 
Re: 99 5.7 rpm

Yep, I have & do, had the boat 4 years now scoots along ok when trimmed out on plane. As I said never wants to run at that rpm, think I may check out my linkage see if I get full throttle when outdrive is engaged. Runs very well and never skips a beat. thinkin possibly thats my issue. Is that possible?
 
Re: 99 5.7 rpm

OK here is my bitch of the day......


KWPLYR

Did you go to school and were you taught the english language???

Example:

Question: Kwplyr, did you have a hamburger for dinner last night?

Answer: Yep, the suds was good.....

CORRECT WAY OF ANSWERING THE QUESTION!!!

Question: Kwplyr, did you have a hamburger for dinner last night?

Correct english answer: Yes I did, it was a cheeseburger with onions, katchup and mustard on a onion roll and it tasted great!!

I dont know about you but when one asks a question, one expects a direct complete answer.

Do me a favor and re read your answer and tell me if it makes any sense to you. It certainly makes NO sense to me.

Also when asking questions here or anywhere else, INCLUDE AS MUCH INFO AS POSSIBLE IN THE FIRST QUESTION AND DONT THROW TID BITS IN AS YOU GO ALONG........
 
Re: 99 5.7 rpm

not for nothing thats a big barge for a single 5.7 to push. There might not be enough mojo to push it any faster.

Why so mush pitch on the props ? Seems to me just to mush pitch. Some marinas will allow you to test the props just as long as they know you will buy a set.

There is also a website that for 10 bucks plus shipping or something like that they allow you to test the props.

With the set you have now i just don't think you will ever get near proper wot rpm's.

That means that poor motor is being lugged and will kill it eventually
 
Re: 99 5.7 rpm

Here's a data point for comparison (similar engine):
5.7L 2 bbl alpha 1 drive in 22ft searay. I run a 14.25" dia. x 21" pitch 3 blade aluminum prop. I forget the exact gear ratio, but I think it's 1.47:1. The boat weighs 4500lbs fully loaded.
I'm a touch over propped. At WOT I get about 4200rpm. But I practically never run at WOT, unless I'm testing something I fixed. Besides, the ocean seldom allows it anyway, and I'm more for the fuel economy than top speed performance.

So, comparing the data available, he's either got way too much prop for that gearing, or likely not enough engine for any of it. I wonder if that engine/drive/prop setup is the orignial from manufacturer.
 
Re: 99 5.7 rpm

YES I have trimed it up as far as possible before cavitation, We're in northern MN Ice Just off the lakes here haven't been able to get it out yet, so I'm quoteing from memory.
kghost its Ketchup not katchup. Guess where they taught you the english launguage SPELLING wasn't in there curriculum. PMSing?
 
Re: 99 5.7 rpm

Spelling is forgiven on the web site,

Incorrect grammar or unintelligible sentences are not!!

You ask a question, you leave out way too much information in your original question.
You add "tid bits" along the way. Many try to answer your questions but when someone asks you a question you only partially answer it.

We are not mind readers and can not answer underlying questions without proper information.

Again there is a lot of collective knowledge on this site and the ONLY way to take advantage of it is to be as informative in your questions and answers as possible.

Try being the one trying to answer questions once instead of asking them and you will soon find out that after hundreds it gets a bit upsetting once in a while......
 
Re: 99 5.7 rpm

The History of all too many boats..

1) Never owned a boat buyer goes to boat show, sees shiny new boat (boat show special with great price tag)
2) Buys boat
3) Finds out boat not fast enough for them
4) Tries bigger pitch prop
5) Same problem...
6) Sells boat
7) Next buyer finds out engine won't get to spec'd RPMs
8) Posts on this or other forum.

Problem??? The boat manufacturer, in an effort to get a nice low sticker price puts the smallest engine in the boat that they think they can get away with.

Another data point... look at my signature for current engine. For those who don't know about this old classic... 23 ft (old school measurement), Deep V, Open layout, i.e., cuddy cabin, Dry weight with original 283 CID engine...3910 lbs. Boat loafs along at a good plane at 2700 RPM with current engine with a 15x21 prop... max cruise RPM is 3400...WOT 4250

http://home.comcast.net/~rfierro/pwpimages/Retriever_2003_A.jpg

No... I don't keep the drive up. That day I was checking for prop damage. Also, shown with original 250 drive.
 
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