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JohnMC
09-25-2012, 11:39 AM
I just purchased a 1986 TriStar 220, engine is a 454, has 225 hours on boat.
PO said there was always a vibration and they had dealer check it out years ago, nothing found to be the issue. Boat hasn't been run much in recent years, only 225 total hours.

In test drives, vibration gets worse as RPM increases past 3000rpm.
I don't believe it's the engine as in neutral we can rev it up and no issues.

After surfing this forum I'm guessing that the prop is slightly damaged, and if it's been this way for the 225hours that I may have a few other parts (assume bushing/bearing) to replace. I assume pulling the prop and looking at it and shaft might clue me into my next steps...

I could run engine in neutral and the shaft should rotate slowly, but I'm guessing that if vibration doesn't start until 3000rpm, its not something I'll see by eye, need to measure.

I'll post photos once pulled.

If replacing the prop any suggestions?

Thanks ahead for any help!

j.mccreight@hotmail.com
09-25-2012, 11:41 AM
need to know which prop is on there now, also the prop could be repaired for ~125 versus 400-500 for a new one

JDK
09-25-2012, 12:34 PM
If it were me, I'd take the prop to a local prop shop for a tune up before I got too excited about any of the other stuff.
You might not see the damage to the prop based on your description of the vibration.

east tx skier
09-26-2012, 10:54 AM
It doesn't take much to cause vibration. Get the prop reworked.

Also, though it is very common, the prop shaft should not spin slightly while in neutral. You have a glaze on your clutch packing that is causing that to happen. It happens to most, if not all, boats over time, but it is not designed to do that.

For what it's worth, I never worried about it on my old boat.

JohnMC
09-26-2012, 12:33 PM
Ok, looking for local prop shop

JohnMC
10-07-2012, 06:06 PM
Dealer found loose rudder box, hopefully this is my problem, I'll still send prop out.

CantRepeat
10-07-2012, 06:19 PM
When was the last time the fluid in the trans was changed? If you don't know I would do that first off. If the trans was rebuild and new clutches installed it's possible the person doing it did not gauge the clutch pack and install the incorrect thickness of snap ring. However, it is sometimes common for them to have some creep in them.

I'm not sure how you check that the prop moving but you should never run the transmission in gear while out of the water. You can do some pretty good damage to the strut bearings by running them dry.

As posted, it doesn't take much in the way of a bent blade on a prop to cause vibrations in the drive line.

JohnMC
10-07-2012, 06:41 PM
PO said trans fluid was likely never changed, it looked good when I checked. Forward shifts smooth, reverse is a little hard going into gear. I've read that Borg Warner uses more clutch plates when trans is behind a 454 vs a 351 engine. I'll change the trans fluid. Dealer should also be checking it as i have them going over the boat too.

mikeg205
10-07-2012, 08:55 PM
PO said trans fluid was likely never changed, it looked good when I checked. Forward shifts smooth, reverse is a little hard going into gear. I've read that Borg Warner uses more clutch plates when trans is behind a 454 vs a 351 engine. I'll change the trans fluid. Dealer should also be checking it as i have them going over the boat too.

Never...omg... looks good and being good 2 different things... which dealer did you go to - Action Sports? There good people...

JohnMC
10-07-2012, 11:04 PM
Yes, Action, in Fenton, I'm looking forward to no-issues in the spring so wanted them to check the boat out and find the issues that must be fixed now, so I can budget time & money to fix. They sold my boat to the PO/ original owner. $28k in 1986...