225 cruising Rpm

hail mary · **Joined:** Tue Dec 17, 2013 11:50 pm **Posts:** 33

Hello Guys
Just got my exhaust cleared , :lol:

and while it was clogged the Rpms would not go above 4500 and speed not over 20mph ,now that the boat goes Fast with no restrictions the rpms go up to 5500 and I did not have it full throttle , so my question , since the gage goes up to 7000 , where should my rpms be while going 40mph,.. or full speed (that is as far as i pushed it yesterday,) and I think the top speed is 45???? Im pretty happy now my boat works like it supposed to. Also The boat has 560 hours on it , the oil was changed at 530 hours when i bought it , what is the hour rating when to change it again> ?
Just had impeller changed , new bellows and lower drive serviced, new boot hoses, new ex. risers. $$ should be good to go for a while. Thanks Roy

ric · **Posted:** Sat Jan 25, 2014 11:38 am

The maximum RPM you want is around 4600rpms at WOT. Don't go past 5000 ever. 7000 and you'll be buying a new engine. Cruise RPM? Your boat is very similar in size/weight/engine/hp to my boat. Cruise RPM should be anywhere from 3000 to 3300 depending on how loaded up you have it.

Time to re-prop! I shoot to cruise at right around 3000 it's the most economical with the boat loaded up how I want it. Our outdrive gear ratios are different but I use a 17 pitch Alpha 4 aluminum 4 blade prop. I cruise comfortably at 3000-31000rpms and WOT is around 4600. No idea the MPH, don't care it's a cuddy not a speed boat. I'm not fond of aluminum props they're quite bad actually, but it was $60. Come summer I'll have a 4 blade stainless Vensura bolted back there.

NiagaraChillin · **Posted:** Sat Jan 25, 2014 11:49 am

hail mary wrote:

the oil was changed at 530 hours when i bought it , what is the hour rating when to change it again> ?Just had impeller changed , new bellows and lower drive serviced, new boot hoses, new ex. risers. $$ should be good to go for a while.

Change your oil every season. Some prefer to change in spring, some in fall. Impeller every other season, but you should check it every season. Its easy to remove the sea-water pump and give it a looksee. Also change your drive oil every season too. Its an easy task and will let you visiually check for milkyness or metal particles in the oil (not good).

Do a search here for those topics. Lots and lots of discussions.

ric · **Posted:** Sat Jan 25, 2014 11:59 am

NiagaraChillin wrote:

hail mary wrote:

the oil was changed at 530 hours when i bought it , what is the hour rating when to change it again> ?Just had impeller changed , new bellows and lower drive serviced, new boot hoses, new ex. risers. $$ should be good to go for a while.

Change your oil every season. Some prefer to change in spring, some in fall. Impeller every other season, but you should check it every season. Its easy to remove the sea-water pump and give it a looksee. Also change your drive oil every season too. Its an easy task and will let you visiually check for milkyness or metal particles in the oil (not good).

Do a search here for those topics. Lots and lots of discussions.

Define "season" because here in Florida we boat 365 days a year. If I changed engine oil once a year that would be bad. Every 100 hours or once a year depending on where you live in the world weather wise is recommended spec. I prefer every 6 months or 50 hours, oil is cheap.

Outdrive oil once a year. Impeller every other year. Speaking of which, it's time for my vessel to get it's full service.

hail mary · **Joined:** Tue Dec 17, 2013 11:50 pm **Posts:** 33

Thanks for the info! , the prop is I believe what came with the boat , also there is another larger new prop that i found in the cuddy but the mechanic said it would be another $70 bucks for some hub kit to make it work , he said the boat would go faster with the bigger prop. ( not to say im not mechanicly inclined , im a electrical contractor just no time or proper tools to do major stuff) so the prop I could change out myself once i get the right kit. Any recommendations for a good prop stainless steel? you can cruise/plane at 3000rpm ?

NiagaraChillin · **Posted:** Sat Jan 25, 2014 1:07 pm

ric wrote:

Define "season"

Season- Flavoring added to food. Usage: "I like to season my steak" :lol:

rics right, I was speaking in a 4 season climate. The warm climate boaters have different schedules for maintenance than we do up here.

ric · **Posted:** Sat Jan 25, 2014 2:24 pm

Mercury props use what's called the "flo torq" hub system which is vastly superior to anything else on the market. Their props are not brand specific. Volvo/OMC/other prop manufacturers use a prop hub that requires a press to install/replace to make work on different engines. Mercury props just use a metal spline adapter that slides in/out with no effort, so one hub adapter kit will work with any prop Mercury sells. No need to buy a hub with every prop you own. It also makes switching the prop to another brand drive just the purchase of the spline adapter that fits the shaft that slides right in.

Another upside is, if you hit something and break the "break away" part of the hub that prevents damage to the drive, it's just another $10 piece that slides in/out. Keep a spare on the boat. Hit something, break a hub... spend the 5 minutes to unbolt the prop and replace it and continue home.

I couldn't imagine owning anything else.

To tell what kind of prop pitch your boat needs you'll have to tell us what's currently on it. Usually on the prop somewhere like 14x16 or 14.75x23

LouC · **Posted:** Sat Jan 25, 2014 2:31 pm

As a general rule, an inboard will last longest if your cruise rpm is about 75% of the max rpm allowed by the manufacturer. I don't know for sure what the max is for the Ford 5.8 but you could use 4600-4800 as a good guide.
In my old '88 I run it at 3200-3500 most times in deference to its advanced age. I'm not in a big hurry trying to get as much hrs/years as I can out of this one.

Surface Interval · **Posted:** Sat Jan 25, 2014 3:03 pm

According to Four Winns fast facts, the original prop for your 225 was a 14.5 x 19. Max rpm range is 4200-4600 for the 5.8 EFI, and this prop should have the engine turning 4500-4600 when trimmed out at top end.. This rpm range should be on a label on the engine. If on the outside chance you have the high output 5.8 EFI HO, max rpm is 4400-4800. If your tach is going above 5000 rpm you either have a prop with less pitch than recommended or your tach is not accurate. I had my tach go bad and read high, like 5500 or more at top end. It also read high at all speeds including idle. Identify what prop size you have. If it is the original and in good shape, you may very well have a bad tach. From this web site's home page click the link to the Four Winns site. Under "customer service" click "view catalogs" and look for your year and "fast facts". You'll find specs on your boat, including approximate rpm/speed, etc. If you do not have a separate tachometer or other means to verify rpm, the rpm and speed information in "fast facts" may give you an indication whether your tach is close to accurate. We usually ran our 5.0 EFI at between 2600 and 3600, but the owner's manual said it can be run at any speed desired.

As I recall Merc props have 15 splines to match the Merc prop shaft. Volvos have 19. Generally, a 2 inch decrease (19" to 17") in prop pitch will increase engine speed by 300-400 rpm. When rpm is well above the max (4600) the increased rpm and decreased pitch will usually result in a loss of top speed. Changing prop diameter will have a rather small effect on rpm. Propellers of the same size from different manufacturers can vary significantly in performance. Blade rake angle, blade area, and propeller blade cupping are some factors that can have a noticeable effect on speed, performance, and handling. Four and five blade props may also produce desirable results.
Hope this helps.

hail mary · **Joined:** Tue Dec 17, 2013 11:50 pm **Posts:** 33

great thanks for all the info I will check the prop because the new one that was on the boat was bigger than whats on there now which in turn means higher rpms with the smaller prop,
How do I attach a picture of my boat for my profile pic ?

NiagaraChillin · **Posted:** Sun Jan 26, 2014 9:24 am

hail mary wrote:

How do I attach a picture of my boat for my profile pic ?

To add pic to signature line, go to User Control Panel (upper right corner of screen), then on the left side of screen under Options, select Profile, then Edit Signature. Above the text box you will see a button marked IMG. Select that, it will put brackets in the text box. Copy and paste the URL of your pic from whatever photo site you use. NOTE: You have to have any pic you want to uplaod in a photo sharing site, you can't upload directly from your computer.

After you get the pic uploaded, go ahead and put the boat details under it for your signature line (see mine for example). Again, welcome and happy posting!

kd4pbs · **Joined:** Thu Sep 05, 2013 10:34 am **Posts:** 350

Your RPM reading is likely due to a falsely reading tachometer. Use an alternate tach to verify.

hail mary · **Joined:** Tue Dec 17, 2013 11:50 pm **Posts:** 33

Hi
Thanks for the input , Just a theory ,,, but the previous owner switched the prop to a smaller size that was original and im assuming because when i bought the boat it was experiencing an exhaust clogging and performance problems that got worse until it started blowing the exhaust hose, and also it would limit the rpms to around 4200 - 4500. Now with the exhaust fully cleared the rpms can go above 5000 (which I keep it under and boat tops out at 40 mph) so im thinking the smaller prop is giving me a higher rpm,(or tach could be reading wrong)

Surface Interval · **Posted:** Mon Jan 27, 2014 6:32 pm

I still think you have either a prop with not enough pitch or a bad tach if you are seeing 5000rpm or more. The 5.0 and 5.8 engines have a max rpm range of 4200-4600. Redline's at 4600. The previous owner may have gone to a prop with less pitch trying to troubleshoot the problem or to mask the issue for sale. Were you able to identify the diameter and pitch on either of the props? The original prop was an OMC aluminum 14.5dia x 19" pitch. This prop should give you approximately 4600 rpm and approximately 45mph on a clean lightly loaded boat. The Four Winns Fast Facts chart shows 46-49mph for top end. At top speed you should have full throttle and the drive trimmed up some (maybe 1/2 to 3/4 on the trim gage or so the cavitation plate is level wit the bottom of the boat or just a bit up from there). If you are seeing 5000 or more with that prop, I am almost certain that your tach is bad. Come to think of it, some other tachs (including mine) have been reading high on occasion. I have used the "percussion adjustment" method on it.......give the top of the instrument a slap or two. Circuit board or other electrical connections may be marginal. It might work.

hail mary · **Joined:** Tue Dec 17, 2013 11:50 pm **Posts:** 33

ok i will try the percussion method and see if it drops down

www.iFourWinns.com

225 cruising Rpm

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