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Message |
    
carl montgomery
New member
Username: cmonty
Post Number: 2
Registered: 11-2009
| | Posted on Sunday, November 01, 2009 - 11:04 pm: | 
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I have a 1994 regal 18 foot bow rider 3.0 mercruiser with a 19 pitch prop.What kind of speed should this boat run?The rpm is 4200. |
Brian Brackett
Senior Member
Username: kainon
Post Number: 1020
Registered: 03-2009
| | Posted on Monday, November 02, 2009 - 12:48 am: |
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Engine RPM 4200
Gear Ratio 1.98:1
Propeller Pitch 19
Propeller Slip 10%
Speed MPH 34.3 |
carl montgomery
New member
Username: cmonty
Post Number: 3
Registered: 11-2009
| | Posted on Monday, November 02, 2009 - 02:16 pm: |
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Is there any easy way to get more speed out of it?Everyone tells me there boats run 45 50 mph??? |
Brian Brackett
Senior Member
Username: kainon
Post Number: 1021
Registered: 03-2009
| | Posted on Monday, November 02, 2009 - 04:31 pm: |
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yea, drop a V8 engine in it, I know boats 20' with 200hp 305ci V8 that get 50, you wont get that with a 4cyl or even a V6. You might get 1-4mph more depending on weight and prop pitch, but with more pitch you will be putting more strain on the engine. With a 21p if you could do 4000rpm you'd get about 36.2.
so a 4.3L V6 Mercruiser with a 1.84 drive @ 4600rpms and a 19p prop would do about 40mph. |
Guy Gaspar
Senior Member
Username: guyjg
Post Number: 5461
Registered: 08-2006
| | Posted on Monday, November 02, 2009 - 07:37 pm: |
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The RPM range for that engine is 4400-4800. Drop the prop pitch to 17P. |
Bondo
Senior Member
Username: bondo
Post Number: 2081
Registered: 12-2006
| | Posted on Monday, November 02, 2009 - 07:53 pm: |
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"Everyone tells me there boats run 45 50 mph???"
Ayuh,... Most of Them are lying to ya anyways.... |
carl montgomery
Member
Username: cmonty
Post Number: 4
Registered: 11-2009
| | Posted on Monday, November 02, 2009 - 10:14 pm: |
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I did put a 17 pitch on it and i got 2 mph less but a little bit better take off but the rpms didnt change.The trim seemed not as responsive with the 17 |
Hy Stat
Senior Member
Username: hystat
Post Number: 1537
Registered: 05-2007
| | Posted on Tuesday, November 03, 2009 - 12:13 am: |
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for a 3.0 to go 50,
it would have to be in a 16 footer |
chiefalen
Advanced Member
Username: chiefalen
Post Number: 327
Registered: 03-2008
| | Posted on Tuesday, November 03, 2009 - 06:29 am: |
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I thought the rpm wot is 4200-4600, for that year 3.0 but then again i could be wrong.
So the bottom is clean? The motor is tuned and timed to perfection?
Do a compression check make sure your spot on compression wise.
Then do a vacuum check heres how.
http://www.secondchancegarage.com/public/186.cfm
http://www.users.bigpond.com/ergoff/vac1.htm
Above is 2 good sites that will help you.
So now you know the motor is running tip top after doing the vacuum test.
So is there any hidden water in the hull weighing you down? Wet foam maybe?
You have alot of gear on board? Weighing you down?
Most tests are done with a 1/4 to 1/2 a tank of fuel onboard.
I would think the 19 pitch prop would be the ticket for you.
However i am surprised the 17 pitch didn't get the rpms up, so here goes.
If it were my boat i would hook a shop tach up make sure of the rpms wot with the 17 and with a gps verify the speed.
post the result. |
gl115
Member
Username: gl115
Post Number: 4
Registered: 11-2009
| | Posted on Tuesday, November 03, 2009 - 07:13 am: |
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boat speedo's are not accurate, gps set to mph is the way to truely tell how fast you are going. |
PugetSounder
Advanced Member
Username: pugetsounder
Post Number: 508
Registered: 04-2007
| | Posted on Wednesday, November 04, 2009 - 01:59 pm: |
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Wouldn't you want to increase the pitch to say a 21P? you might get 2 mph faster. |
Hy Stat
Senior Member
Username: hystat
Post Number: 1539
Registered: 05-2007
| | Posted on Wednesday, November 04, 2009 - 02:01 pm: |
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no, his rpm is already 4200. don't want to lug any more than that or you'll risk cupping the valves and damaging the engine. |
carl montgomery
Member
Username: cmonty
Post Number: 5
Registered: 11-2009
| | Posted on Wednesday, November 04, 2009 - 11:27 pm: |
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I really appreciate all the help i can get with advice...Im new to the boat game but very familiar with car engines so everyones advice is helping me solve this problem if i have one.The hull is very clean and the boat is in excellent shape for a 94 model.Goin to do vacuum and compression check on it this weekend.You guys are a big help...Thanks and will post results saturday... |
chiefalen
Advanced Member
Username: chiefalen
Post Number: 332
Registered: 03-2008
| | Posted on Thursday, November 05, 2009 - 06:09 am: |
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i had to come back one more time to post that speed is really not the issue.
The issue is wot. The all important numbers are rpms.
That motor should be between 4200-4600 no more, that is with the throttle all the way down and going balls out.
What ever speed you can squeeze out of it is secondary.
One other little note, you could run it wot and maybe the motor will last and last or it will grenade.
Makers of motor say that the motor should run 3/4 of wot. The last 1/4 left in reserve for avoiding a accident.
Wot should be checked every once and a while and held there for a few minutes, not all day every day.
My friend has a Bayliner cuddy, 18' 3.0l merc 1993
wot just touchs 4600 43-45 mph just me and him on the boat with fishing equipment and maybe the tank half full oh 19 pitch prop. Light boat.
My boat 19' 86' Citation cuddy heavy,heavy boat, 86' 140 hp 3.0 merc. Wot just under 4600, 17 pitch 35 mph top speed.
I have tried a 15 pitch too high a rpm and no extra speed.
I can't take the pounding i run it 3000-3500 rpm, 20-25 mph tops never more.
I check wot every once and a while about a mile from the dock so if it blows i can almost swim home.
Good luck and enjoy it and forget them lies your friends are telling you.
These the same friends that are telling you they are sleeping with Pamela Anderson? |
Hy Stat
Senior Member
Username: hystat
Post Number: 1540
Registered: 05-2007
| | Posted on Thursday, November 05, 2009 - 10:28 am: |
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My friend has a Bayliner cuddy, 18' 3.0l merc 1993
wot just touchs 4600 43-45 mph just me and him on the boat with fishing equipment and maybe the tank half full oh 19 pitch prop. Light boat.
Was that GPS?
I have a 1992 185 Bayliner cuddy. The 3.0 would get it to 36 mph GPS with me holding my breath.
I repowered to a 185HP V6 and it does about 43-44 now. |
chiefalen
Advanced Member
Username: chiefalen
Post Number: 333
Registered: 03-2008
| | Posted on Thursday, November 05, 2009 - 05:32 pm: |
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Hy drill a hole in the deck of the cuddy near the bow and see if there is water hidden in there was in my buddy's boat.
When was the last time you did a compression test? |
izdbye
Member
Username: izdbye
Post Number: 14
Registered: 11-2008
| | Posted on Thursday, November 05, 2009 - 07:01 pm: |
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My 2005 Bayliner 185BR with the 3.0 does 39mph (GPS) @ 4800 rpm with a 21 pitch 4 blade prop. |
Hy Stat
Senior Member
Username: hystat
Post Number: 1541
Registered: 05-2007
| | Posted on Friday, November 06, 2009 - 01:06 am: |
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When was the last time you did a compression test? when I sold the 3.0 3 years ago. it was 145 across - had less than 100 hours on the engine. I have a V6 in the boat now.
The hull is dry. There is no water under the floor. The boat is showroom condition.
It runs low 40's with the V6 and I am at sea level. |
carl montgomery
Member
Username: cmonty
Post Number: 6
Registered: 11-2009
| | Posted on Friday, November 06, 2009 - 09:09 pm: |
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Im goin to run a compression test and check vacuum Saturday and will post the results.The hull is very clean.Goin to look and see if there is water in front of boat under bow...Its dry in the ski storage and engine well area.The bilge pump works but there isnt never water in there. |
mike weakley
Member
Username: mikey43
Post Number: 16
Registered: 10-2009
| | Posted on Saturday, November 07, 2009 - 12:23 am: |
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question what is a good allaround prop for a 21' baja with a 350 v8 alpha 1 drive? any ideas? |
Bondo
Senior Member
Username: bondo
Post Number: 2087
Registered: 12-2006
| | Posted on Saturday, November 07, 2009 - 11:39 am: |
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"question what is a good allaround prop for a 21' baja with a 350 v8 alpha 1 drive? any ideas?"
Ayuh,... The prop that allows the motor to run the proper rpms at wot, that gives Good handling character traits... |
chiefalen
Advanced Member
Username: chiefalen
Post Number: 336
Registered: 03-2008
| | Posted on Saturday, November 07, 2009 - 06:24 pm: |
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Find a marina that will let you test a few 19-21-23
Start with the 19. I read there is a national chain that allows you to try a few. |
carl montgomery
Member
Username: cmonty
Post Number: 7
Registered: 11-2009
| | Posted on Sunday, November 08, 2009 - 12:56 pm: |
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I ran a compression check today...Cylinder one is 110 and the other three are 160...There are no vacuum lines on carb to chech vacuum...I looked in valve cover and no signs old old corroded oil or build up.Looks very clean.Tuned up and running good.Timing set on the money.I took the boat out with one half tank of fuel with gps..4200 rpm 35mph...Did not see any signs of water in hull...Opinions???Should i be concerned about low number one cylinder???The prop is a 19 pitch now...The pic has the old 21 four blade pitch...I bought this boat in the middle of summer and only had it out five times...First boat i ever owned...I think it looks very clean for a 1994.I just want to make sure boat will be good for summer fun or do engine work over the winter??? |
Brian Brackett
Senior Member
Username: kainon
Post Number: 1032
Registered: 03-2009
| | Posted on Sunday, November 08, 2009 - 03:44 pm: |
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sounds like a bad valve on that cylinder, or some scoring in the cylinder wall or piston, more than 10% difference is a concern. .. as for a compression test, some carbs have port that can be used on the back side of the base of the carb. and or on the top of the manifold a brass plug. |
chiefalen
Advanced Member
Username: chiefalen
Post Number: 337
Registered: 03-2008
| | Posted on Sunday, November 08, 2009 - 05:04 pm: |
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you performed the test on a warm motor with all the plugs out and the throttle fully down? |
carl montgomery
Member
Username: cmonty
Post Number: 8
Registered: 11-2009
| | Posted on Sunday, November 08, 2009 - 05:09 pm: |
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No...but i will do that tomorrow and repost results...Thanks... |
Guy Gaspar
Senior Member
Username: guyjg
Post Number: 5472
Registered: 08-2006
| | Posted on Sunday, November 08, 2009 - 07:00 pm: |
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Perform the wet test w/a tablespoon of motor oil after the dry test. If the compression remains the same then it's a valve problem. If it isn't backfiring it may just be carbon on the intake valve. If compression goes way up then it's a ring issue. |
