View Full Version : Maxed out , rpm?

10-28-2008, 03:46 PM
hello everyone im having some troube getting my 89 tristar above 3 grand in the water. its a 351 windsor with 1111 hours. it runs to six grand out of the water witht he flusher but int he water its like no go....

10-28-2008, 03:56 PM
What transmission does the boat have and what size is the propeller?

10-28-2008, 04:15 PM
Well as far as the trans I donno I just bought it how would I tell? The prop is a little beat ut but the numbers look to be a 5 and a 76? Iit runs about 34 is the max with no wind on calm water

10-28-2008, 04:36 PM
If the prop is a little beat up that would be my first guess. It is amazing how huge a difference a little prop damage can make. That boat should be able to run about 42mph wide open at about 4800rpm.

10-28-2008, 05:00 PM
The blades are in great shape its just where the numbers are ground in are worn down and or completly worn off. I mean no matter how hard ypou push her she won't go a tad over 3 grand so I found weird she wouldn't get warm while it was on water the boat stayed at 110 dergrees all day grabted the water was very cold like 35 degrees while is was on the flusher in my driveway it would hit 160 +r 170 and well above what it would do in waterm I know water puts a large strain on the boat but still

10-28-2008, 05:29 PM
Clogged fuel filter maybe??? check all your basic, collasped/dirty air filter, fuel filters.

10-28-2008, 05:34 PM
Could be a bad prop - say, a 14x20 on a direct-drive boat?

The fact that it runs fine out of the water, but poorly in, would point to a prop issue.


10-28-2008, 05:51 PM
With only hitting 3K rpm I would guess its either the WAY wrong prop or you have some sort of runability issue.

Check the plugs and wires, make sure it is running on all cylanders. This happens more than you would think, a fouled plug, a melted wire, a bad connection you never know.

Check fuel filters.

Also not building temp could be a bad thermostat, you need to get that addressed as well. This boat should be running at 140-160 degrees.

10-28-2008, 05:59 PM
What prop do you guys reccomend? Like I said it runs great on the trailer but that does me month good. Plus I'm gunna do all the maintance this winter plugs wires filters thermostat hoses belts and while I'm at it I'm going to check compression in all cylinders

10-28-2008, 06:05 PM
Get with Eric at OJ, he'll make sure you get the right prop. You'll need to know which transmission you have as they require different props. The Powerslot runs a slightly bigger drive shaft and is a gear reduction, the standard tranny is a 1:1 ratio.

10-28-2008, 06:14 PM
I'm sorry I'm really new Eric..how do I get ahold of him?

10-28-2008, 06:15 PM
I would also add that it may be fuel pump related as well ... if the volume of fuel is not adequate you could end up with something like that although a worn pump usually cuts out for a second under load (like it runs fine up to 2.5K RPM but then cuts out at slalom speed) ...

The fuel pump on that car is crank driven and easy to replace.

Just a thought.

10-28-2008, 06:24 PM
I'm sorry I'm really new Eric..how do I get ahold of him?

Eric at OJ Props. He is the first poster in this thread (EJ OJPROP). Google OJ Propellors and you should be able to get their contact info.

To see if you have a powerslot transmission, you need to get a view of the top of your transmission. On the top there should be a small plate with the serial number and also it will have a ratio, either 1:1 or 1.5:1. 1.5:1 is the powerslot.

10-28-2008, 06:27 PM
Well that makes sense to me too because at a dead stop or 5 mph if you punch it it delays for a seconf then starts to plane out but it takes a second to get to that speed

10-28-2008, 06:35 PM
I'm sorry I'm really new Eric..how do I get ahold of him?

10-28-2008, 06:40 PM
A hesitation could mean bad accelerator pump in carburetor. With engine OFF try moving the throttle while looking into top of carb...........you should see 2 streams of gas squirting into intake manifold.

If you're only hitting 3000 rpm, check to make sure choke plate is wide open. It should be wide open when engine is hot (you said it runs cold, so maybe your choke is not opening up all the way creating an air restriction, therefore not letting the rpms climb up any higher) Install a new 160 degree thermostat.

If you have a 4 barrel carb (I think you do) maybe your secondaries are not opening. This would also cause the engine not to rev up under load.

Let me know what you find. Hope this helps.

10-28-2008, 08:53 PM
Yea it is a 4 barrel what's the most effective way to check the secondaries?

10-29-2008, 06:47 AM
I'm sorry I'm really new Eric..how do I get ahold of him?

Give me a call at 800-359-9730 Eric @OJPROPS.COM

10-29-2008, 09:04 PM
Game plan is friday im going to do a thermostat,plugs,wires,fuel filter,air filter, and a new prop OJ 13x11.5 as recomended by Eric and well see what happens i dont know if ill get it out on the water this weekend im going to try getting the prop by saturday hopefully. Maybe this will take care of my problems....

10-29-2008, 09:09 PM
Well that prop is a monster out of the whole....made a HUGE difference on my boat.

10-29-2008, 09:19 PM
hopefully i hope the work im gunna do will take care of my issues. All i can do is try so.

10-30-2008, 09:55 PM
Yea it is a 4 barrel what's the most effective way to check the secondaries?

If it has mechanical secondaries, move throttle to wide open (with engine off!) and see if all 4 butterflies open.

If it has vacuum secondaries, harder to check. You may have to get someone to drive the boat (with engine cover off) while you watch the carb to see if secondaries open. Usually you will feel and hear the 4 barrel kick-in just about 3000+ RPM's.

None of this means anything if your choke is not wide open at operating temp.

10-31-2008, 07:24 PM
Well I found the problem I took the housing off for the thernmostat and well there was no thermostat there. So I put the one in that I got rom the part store and a gasket put it on and the it didn't seal spraying water all over and then over heated. Does anyone have the part number foir the right thermostat I can get at a parts store I wanna use the boat tomorrowm also does the spring side of the thermostat go into the housing or manifold. BTW new prop on its way thanks everyone

10-31-2008, 08:29 PM
Try here


The spring always goes toward the manifold
Make sure you use gasket adhesive on the gasket.

10-31-2008, 08:52 PM
I did but I used an automotive thermostat... Iwill that one work?

10-31-2008, 09:02 PM
Most auto t-stats are 180 or higher, yours should take a 160. I would stick with the marine one if you can.

(is the one you bought a 180??)

Gasket might be different also.

10-31-2008, 11:11 PM
no its a 160 (well thats what the genious parts guy said) and i also drilles a few small holes in the flange of the thermostat.