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Posted: Mon Aug 23, 2010 2:39 pm
by shawzy44
I've been playing with the tabs for a while now. I have them reacting MUCH quicker and can get her to plane fairly quickly.
I get about 12kt @2700 RPM and WOT 23kn @4400 RPM full fuel and water.
Posted: Mon Sep 12, 2011 10:17 pm
by herpleasure
Dreamer,
I am interested in your props. I have a 79 f28 that is doing 2800PRM (which is all it will do) and 12 MPH. The motors run good. You seem to have found the key
Posted: Mon Sep 12, 2011 11:19 pm
by prowlersfish
herpleasure wrote:Dreamer,
I am interested in your props. I have a 79 f28 that is doing 2800PRM (which is all it will do) and 12 MPH. The motors run good. You seem to have found the key
Sounds like you have a fouled bottom and or running gear
Posted: Mon Sep 12, 2011 11:20 pm
by prowlersfish
herpleasure wrote:Dreamer,
I am interested in your props. I have a 79 f28 that is doing 2800PRM (which is all it will do) and 12 MPH. The motors run good. You seem to have found the key
Sounds like you have a fouled bottom and or running gear
Posted: Mon Sep 12, 2011 11:20 pm
by prowlersfish
herpleasure wrote:Dreamer,
I am interested in your props. I have a 79 f28 that is doing 2800PRM (which is all it will do) and 12 MPH. The motors run good. You seem to have found the key
Sounds like you have a fouled bottom and or running gear
Posted: Mon Sep 12, 2011 11:27 pm
by Dreamer
The two things that made the biggest in Dreamer, was rebuilding the engines with a very mild cam. New carburetors, and stripping the bottom and using VC-17. I know that's more than two. The props I believe are at the factory pitch.
Posted: Tue Sep 13, 2011 9:01 am
by willietrojan
I guessing your engines are the original, how many hours? I would suggest getting a compression test, this sound like the engines are worn out
Posted: Tue Sep 13, 2011 1:06 pm
by prowlersfish
2800 rpm should be faster then 12 MPH . 2800 rpm is 2800 worn out or not ,
Willie have you found a new boat yet ?
Posted: Tue Sep 13, 2011 2:04 pm
by Capt. Z
prowlersfish wrote:2800 rpm should be faster then 12 MPH . 2800 rpm is 2800 worn out or not ,
Willie have you found a new boat yet ?
I have to agree with Paul. 2800rpm is where I cruise at with my F28. 2800rpm is right at 22mph, WOT is 4100 rpm at 34mph. The 318s are no where near fresh either, 1600hrs.
With a little more info maybe we can help you get to the "bottom" of your problem!
Posted: Tue Sep 13, 2011 8:01 pm
by foofer b
prowlersfish wrote:It is not a engine problem !!!!! your only gets 13-14 knots at 3200 ? well no matter what you do to those engine you still only going to get 13-14 knots at 3200. you could tune them up put a blower on it and get 700 hp out of them But your still only going to get 13-14 knots at 3200 rpm .
unless the engine is missing don't waste you time with a compression check . even if you had 2 dead clyders it will not change your speed at a given rpm. (yes of course it would efect top rpm. )
look else where
Once again Prowlerfish is spot on. Rpm is Rpm no m,atter what the HP.
Posted: Wed Sep 14, 2011 4:10 am
by alexander38
captainmaniac wrote:If you have to give your mechanic a list of what to check to diagnose your problems, maybe you found your problem - you need a new mechanic! If he can't tell *you* what needs to be checked, don't let him touch them.
omg ! we agree
I've a question, will it rev up out of gear ? lack of gas at higher rpm it'll back fire and or fall off all together. And whats the bottom look like a fouled bottom or a painted one that looks like the moon will kill rpm/speed. also have you checked alignment ?
And engine hrs. don't kill engines lack of maintenance kills them, my 454's have over 1700 on them and push me up 25 knots with a smooth bottom.
Posted: Wed Sep 14, 2011 1:55 pm
by shawzy44
Alexander38,
What do you mean by alignment? Alignment of what exactly?
Posted: Wed Sep 14, 2011 6:48 pm
by prowlersfish
Engine alignment
Posted: Thu Sep 15, 2011 5:16 am
by alexander38
prowlersfish wrote:Engine alignment
to shafts and cutlass bearings
Posted: Thu Sep 15, 2011 6:55 am
by prowlersfish
alexander38 wrote:prowlersfish wrote:Engine alignment
to shafts and cutlass bearings
Not exactly , you aligne the engine to the shaft and the shaft to the cutlass , its really 2 different things to do , but one effects the other . as a general rule , cutlass/strut alignment will effect cutlass wear , engine to shaft can cause vibration and possible shaft failure .
To cause a power loss the alignment would have to be so far off the shaft would be in a bad bind . if you can rotate the shaft then I don't think this is the issue .