Transmission Slipping?

[Table Rocker]

Originally Posted by jwp1504

There are very loud knocks when the revs drop. Again, i have no idea what this is!

I think if you start a new thread on this, it will get more traction.

[jwp1504]

Originally Posted by Kyle

Back on the thread jack question


The boat rolls 4k plus seems to bounce off rev limit and takes 11 seconds to hit 30 mph and winding it out.

The second vid shows the engine falling off at 4+k and tops out -40 mph. Peaks at 4800


I am very curious that the boat is struggling so hard to get to 30 but is reving high rpm.


Before y'all flame me

1) Explain why the engine is screaming and takes forever to get to 15-30 mph. Is this a low HP engine?

2) instead of just dropping the throttle to the floor can the boat be driven normal rolling into the throttle and the prop staying somewhat even with rpm all of the way to 36mph.

3) did this just start doing this or is the boat new to you.

4) is the correct prop on the boat

5) what is the factory rev limit

6) why at 30 mph to wot does the boat creep up to speed.



Rpm turning (screaming) and boat not accelerating is a sign of slipping.

It looks like a tranny problem since you are spinning 4k and the mph starts increasing extremely slow. My boat will be up to 36mph in 6-7 seconds. 11 seconds we will be well over 40 possibly 46-47 mph on GPS

I would check tranny fluid color, smell, level, etc

Next I would evaluate the proper use of the boat under 4k rpm

If the tranny and engine perform correctly then agree there is obviously other issues.


A TPS that has a bad spot can confuse the ECM and can either lean out the engine or flood it. And there are other sensors that will cause the engine to bounce at any rpm.



My main concern is the fact the engine screams and the boat doesn't want to come up to speed.

Is it full of ballast, weight, etc there is no reason for the engine to take 11 seconds to come up to speed.

4k rpm and keeping it while accelerating is not a sign of bogging down. Engine is spinning strong and has weak acceleration.... Then we have 4-4800 rpm bouncing. Are we hitting rev limit???? If yes then you do not have engine problems.

If your rev limit is not hitting then you more than likely have a sensor failure.


Again boat has poor acceleration with high rpm. I need an explanation for this.

1) 330hp LTR engine
2) Even when i slowly increase the throttle to 3600rpm it still has the issue
3) I have owned the boat for 6 months and put 20 hours on it. The issing just started happening. There is no rev limiter as such, at full throttle the engine will do approx. 4800rpm. It doesn't cut out like a car rev limiter it just won't go any faster.
4) Yes, i have the correct prop on the boat and it was recently serviced.
5) No idea!
6) What do you mean by "WOT"?

There is no ballast in the boat and there is 4 poeple..

Cheers fr your help.

Joel

[jwp1504]

Hi Guys,

I have started a new thread..

http://www.mastercraft.com/teamtalk/...445#post915445

Sorry for jacking this one!!

[Scot]

Originally Posted by jwp1504

Hi Guys,

I have started a new thread..

http://www.mastercraft.com/teamtalk/...445#post915445

Sorry for jacking this one!!

No worries, you caught my interest.

WOT= wide open throttle. I assumed you were opening up the throttle when the revs jumped up, not the boat doing this on its own, which would definitely be a slipping issue.

[Scot]

Machine shop is afraid to crack the strut, won't touch it. Lag bolted it to a 4x4 and 2x4 side by side, used a shovel handle through the tube, couldn't get it to budge. Tomorrow I will take it to my local marine shop (not my favorite option as I have mentioned before) but they have a pretty good metal/body guy.

I would love to give this shop more business but how can I justify it when their store prices make west marine look like a bargain, they quote me "like 700 or 800" for a shaft, and their "alignment" left my shaft riding on the log and two hands to turn the prop. I wish their metal guy had his own shop.

[Scot]

ground the strut base down with emphasis on the corner that needed to come up. Didnt line up. Put a washer on the opposite corner, still didnt line up.

Then I bolted it on tight, put a pipe wrench on it with a come-along to the trailer axle. Got it nice and straight this way.

Took it apart and when I went to put it back together a little bit later it still lined up crooked. Did the brass spring back? Should I try this again with heat? Cant get this damn thing to line up! I am tempted to just scrap this shaft and strut even though I just spent a hundred bucks on new bushings for this one.

[CantRepeat]

Originally Posted by Scot

ground the strut base down with emphasis on the corner that needed to come up. Didnt line up. Put a washer on the opposite corner, still didnt line up.

Then I bolted it on tight, put a pipe wrench on it with a come-along to the trailer axle. Got it nice and straight this way.

Took it apart and when I went to put it back together a little bit later it still lined up crooked. Did the brass spring back? Should I try this again with heat? Cant get this damn thing to line up! I am tempted to just scrap this shaft and strut even though I just spent a hundred bucks on new bushings for this one.

http://www.elberts.com/index.htm

Call them for underwater gear. When I bent my strut I called them and just gave him year make and model.

http://www.elberts.com/underwatergear.htm

[thatsmrmastercraft]

Originally Posted by Scot

ground the strut base down with emphasis on the corner that needed to come up. Didnt line up. Put a washer on the opposite corner, still didnt line up.

Then I bolted it on tight, put a pipe wrench on it with a come-along to the trailer axle. Got it nice and straight this way.

Took it apart and when I went to put it back together a little bit later it still lined up crooked. Did the brass spring back? Should I try this again with heat? Cant get this damn thing to line up! I am tempted to just scrap this shaft and strut even though I just spent a hundred bucks on new bushings for this one.

That darn strut is kicking your butt. May have to over-correct when you torque it to end up true. Wouldn't have thought it would take so much effort.

[Scot]

Originally Posted by thatsmrmastercraft

That darn strut is kicking your butt. May have to over-correct when you torque it to end up true. Wouldn't have thought it would take so much effort.

Me either.

Think I got it now. My torquing worked again but it slipped back a bit when I loosened it again.

So I applied 5200, snugged up the 4 outer bolts and torqued it until the shaft touched the opposite corner of where it used to ride. Tightened the bolts and took the pressure off and it sat right where I wanted it to. Put the four inner bolts in and snugged them up. Put a couple more cranks on the winch to bias the shaft toward the opposite corner of where it rode before and tightened all bolts. I will keep the winch where it is for a day and hopefully when I release it everything will be close to center. I am banking on a little play in the bolt holes (not much), the 5200 holding everything in place, and a little bending of the strut.

After I release the pressure I am going to watch the shaft for a day or so and make sure everythin doesn't recoil to its old position. If it does it's no more mr. nice guy- heat, a lot of pulling and whatever happens, whether its straightening this thing, breaking it and buying a new one, or ripping the bottom of my boat apart. I sure hope its not the last one, but hopefully everything works the first time.

[Scot]

I found a machine shop that is willing to fill the grooves in my shaft and turn it back down.

Anyone have any input as to whether it is a good idea or not to try this?

If not I will probably just run this shaft as is. Not much play in the shaft once its in the strut, just want to reduce vibration if possible without replacing the shaft.

Also, does anyone know if vaseline will damage the cutlass bushings if I use it to check rotation while dry? I wouldn't think so but my transmission manual warned against using it on the seals as it can damage the rubber, not sure if that applies to something like these bushings.