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-   -   no power (https://www.moyermarineforum.com/forums/showthread.php?t=10871)

Joe Miller 09-03-2018 10:49 AM

no power
 
Hello All,

When I brought my boat in from the mooring field last week I could get no forward power out of the gear box.
It seemed the forward gear was not engaging properly.

If I pushed the gear lever all the way forward and tried to increase throttle the engine would bog down to the point of stall. When boat was in neutral engine could rev up as high as it wanted.

Could the forward adjustment be to tight or the throw on the lever be to long?

When the boat was taken out of the water there was a fair amount of barnacle build up on prop and shaft.

I have not removed the gear box cover as I am still waiting on head gasket and don't want too many things going on at once.

Any direction would be helpful.

Thanks,

Joe

Mo 09-03-2018 10:58 AM

Joe, I worked on one a few years back that would stall when put in gear, it just didn't have it...it did work in reverse, although not great. The culprit, in the end, was stuck valves. Thumb test compression was good, however when we put a gauge on it we knew. Cleaned up the valves and reseated them and all was good. You will have the head off anyway to change the gaskets so it's a good opportunity to check all of that.

JOHN COOKSON 09-03-2018 11:11 AM

The packing could be a a bit tight.
Is the packing nut hot after the engine has been run in gear?
If the packing is tight and gets to hot it can burn the shaft.

TRUE GRIT

Joe Miller 09-05-2018 05:53 AM

Hello Mo, head is off so no checking compression. I could turn the engine over by hand to check that valves move.

John, I did change packing and grease packing box at grease nipple, there has been no drip and when I first moved to mooring the packing box was warm. The trip to mooring field is 5 minutes. It was suggested that I back off packing nut until it leaks and slowly tighten. I may have the packing in so tight it will not leak in which case should I remove and repack.

Thanks,

Joe

roadnsky 09-05-2018 10:36 PM

Quote:

Originally Posted by Joe Miller (Post 114257)
...there has been no drip and when I first moved to mooring the packing box was warm....
It was suggested that I back off packing nut until it leaks and slowly tighten. I may have the packing in so tight it will not leak in which case should I remove and repack.

Joe-
That is for sure too tight. Back off the nut until it drips.

Please see POST #15 in this thread and maybe download the Don Casey article. ;)

sastanley 09-05-2018 10:45 PM

If the head is off, I would 100% recommend you turn the motor over by hand to observe valves..Also, I would individually inspect each valve while open and closed to make sure there is no build up on the valve or a bad valve seat and make sure it is sealing effectively. A little carbon on the valve can wreak havoc on compression. If a valve has any issue, the time to fix it is while the head is off.

Mo 09-06-2018 06:25 PM

Quote:

Originally Posted by sastanley (Post 114259)
If the head is off, I would 100% recommend you turn the motor over by hand to observe valves..Also, I would individually inspect each valve while open and closed to make sure there is no build up on the valve or a bad valve seat and make sure it is sealing effectively. A little carbon on the valve can wreak havoc on compression. If a valve has any issue, the time to fix it is while the head is off.


Will only take about an hour to remove, clean and relap valves. Joe, remember the guy that helped you rebuild the engine in the boat you sold...he should be able to do that in no time.

Mo 09-06-2018 06:26 PM

Quote:

Originally Posted by sastanley (Post 114259)
If the head is off, I would 100% recommend you turn the motor over by hand to observe valves..Also, I would individually inspect each valve while open and closed to make sure there is no build up on the valve or a bad valve seat and make sure it is sealing effectively. A little carbon on the valve can wreak havoc on compression. If a valve has any issue, the time to fix it is while the head is off.


Will only take about an hour to remove, clean and relap valves. Joe, remember the guy that helped you rebuild the engine in the boat you sold...he should be able to do that in no time. It's a good opportunity with the head off.

Joe Miller 09-08-2018 11:01 AM

Hello Shawn/Mo,

I turned engine over by hand and all valves work but I think I will heed your suggestion and remove and re lap valves as it seems the prudent thing to do.

I have 18" of clearance on valve side of engine once manifold and carb are removed, so good access.

Joe


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