Reply With QuoteDid you check the engine alignment?
Ok just had the new motor put in and had a chance to take it out for a shake down run today, Motor ran great but I have a bad vibration and cant figure it out. I didnt have this vibration the last trip what can cuase this?
Did you check the engine alignment?
Tinkerboater:
Did you check the engine alignment?No I did not, I had the motor installed for me becuase I had no time. I just went out and looked and the motor sits in brakets front and rear, those brakes mount to the boat and dont have any adjustments for moving the motor alignement around so im thinking thats not my problem. I wonder if it is the drive shaft? Its just wierd that I didnt have this problem before.
Tinkerboater:
Did you check the engine alignment?Tinker boater why do you think it might be the alignement. The reason I ask is because we had a Dominator pump seize up on us over the weekend and we can't figure out why. We had previously realigned the engine because it sat turned so it was lower on one side more then the other. We removed the Hardware and redrilled the mounting holes and put it all back together. But we didn't the change the alignement on it. As soon as we took it out on the lake about a mile from the docks it started to seize so we killed it and got towed back to the docks.
did you change from mark4 to gen5 bbc? assuming you have a chevy, if the engine builder didnt use the correct flexplate you'll get an annoying,and costly vibration.
BOBALOO:
did you change from mark4 to gen5 bbc? assuming you have a chevy, if the engine builder didnt use the correct flexplate you'll get an annoying,and costly vibration.I used the same block but did replace the crank, and purchased a new flex plate with the excact same one. Tonight im going to pull the drive shaft to isolate the problem with either the motor the shaft or the pump.
Sorry guys--Didn't know it was a Jet boat. I don't know a lot about Jets just I/O's and engines. If the new crank was not ballanced to the new rotating parts that can cause a vibration but it would have to be off a lot in order for it to be felt.
Ok just pulled the drive shaft out and started the boat and I cant feel any vibration. I spun the impeller by hand and cant feel any thing abnormal but then again I have now idea what to be looking for since this is my first go round with a jet drive, the U Joints dont look worn and I cant feel any slop at all so now im stumped. I measured from the bell housing to the front of the pump on each side and one side is a 1/8 off, Is this the aligment you talk about and could that cuase a serious vibration?
Seperate question, My old 454 only ran up to 4000rpms and the boat was GPSed at 47mph what impellor do you think I have?
The new 454 has MUCH more HP and wants to rev above 5000rpms, what impellor do I need to run 60mph at 4000rpms?
Thanks for all the help
Check your u-joints for binding, not slop.
Boater Bill:
Check your u-joints for binding, not slop.When I rotate on side it seems to have a kink in it where the other side is smooth and very loose feeling.
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