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Marlin275
09-09-2007, 01:17 PM
I heard this clanging sound in the engine that would come and go.
Then it got worse and yet the boat ran great, nothing showed up on instruments and it ran as fast as it ever did.
I called my engine mechanic that sold me this brand new engine last year.
He has been too busy and health problems etc.
The noise was bad then it would go away and come back.
Last time I took it out the noise would not go away.
I talked with another engine mechanic and he said it must be a problem with the front of the engine, bad bearing in the water pump etc.
I started it up on the hose and it sounded worse than ever.
I shut her down and pulled on the belt and could hear noise.
I started her up and went to check the water in the exhaust and the noise had stopped.
Just then I noticed the belt had fallen off the water pump then I noticed this front crank pulley had fallen in the bilge.
How bad is this?
Do you have to pull the engine to get it all back on?
It does not look like the bolts are sheared.
Thanks for any help in understanding this.

gcarter
09-09-2007, 01:36 PM
The harmonic balancer came apart!!!!!!!
Not too serious. Look on Jegs or other on-line hot rod parts supplier. This doesn't happen often, thank goodnes.
It looks like the bolt holding the balancer onto the crankshaft unscrewed itself and came out, then the hub came off the crank end. Normally the hub is a light press fit......so there may be some wear on the erankshaft end.
So, I'd suggest buying a new harmonic balancer, re-use the pulleys on the new balancer, but check for fit of the new balancer on the crankshaft end. Also look and see if the bolt holding the balancer onto the crankshaft end is broken and some of it may be still screwed into the crankshaft.
Others will have other suggestions.

mrfixxall
09-09-2007, 01:41 PM
looks like your missing the harmonic ballancer bolt (7/16 fine thread) if a chevy? anyways locate a bolt and screw it back togrether...if its a chevy 327 then you have to retap the crank,,their pressed on..it almost looke like in the one pic that the bolts sheered off, or are they aleignment studs:bonk:

Marlin275
09-09-2007, 01:45 PM
George thanks for your quick response.
Do I need to pull the engine to do this work?
X-18
350Q
Engine turned around
Chris Craft style

gcarter
09-09-2007, 01:59 PM
You shouldn't need to...it just depends how much room you have at the "front" of the engine. It seems there should be another round piece floating around in the bilge somewhere. It would be about the same diameter as the pulleys and about 1" thick and heavy, also look for some thin pieces of rubber. Look for the bolt that held it on......also look for damage to the timing cover, from the balancer grinding on it, hopefully you won't find any.

gcarter
09-09-2007, 02:01 PM
"Chris Craft Style"....I think I know what you mean....maybe a few more pictures.

gcarter
09-09-2007, 02:03 PM
Do you mean the flywheel is at the "front" of the engine?????
Then these un-attached bolts could be used to hold on the flywheel????

Marlin275
09-09-2007, 02:19 PM
Do you mean the flywheel is at the "front" of the engine?????
Then these un-attached bolts could be used to hold on the flywheel????

Exactly!
The 350Q is turned around in the boat so the back is the front and the front is the back.
They did this to get the engine down lower.
Here are some more photos.
Will look for that piece that you mentioned.

gcarter
09-09-2007, 02:31 PM
Well, in this case, it looks like all you need to do is buy some new flywheel bolts and install them through the hub and pulleys. Well, you need to torque them correctly also. You might check the threads in the crank mounting flange and make sure they are in good condition, maybe chase them with a tap.

Marlin275
09-09-2007, 02:42 PM
I rechecked the bolts and it looks as though they might have sheared off?
Can this be fixed in place or pull engine?

gcarter
09-09-2007, 03:24 PM
Make sure of what you're looking at. It looks to me like the flywheel moved from its original position and what you see through the bolt holes is the flywheel mounting flange. The reason I say this is because the bolts through the pulley hub look complete. Try to turn the flywheel on the crank flange and see if you can align it with the threaded holes. If you can't, or if they are sheared, then you'll probably have to pull it. Also, there should be a dowel pin somewhere in the mix. I don't see any indication of it except for the hole in the pulley hub and the flywheel.
If the bolts are sheared, a person working carefully may still be able to back out the remaining parts of the bolts w/o removing the engine.

gcarter
09-09-2007, 03:28 PM
If you remove the starter, you may have more room to try to move the flywheel in relation to the crank.

Marlin275
09-09-2007, 04:05 PM
George, thanks for all your help !
This always happens on Sunday when everything is closed!
Here are two more shots of the pulley bolts.
One bolt is worn with no threads,
all the rest look sharp tip like shear?

gcarter
09-09-2007, 04:11 PM
They could look sheared if they rubbed on the crank flange.
I'm guessing the bolts backed out, and the pulley hub finally fell off.
Can you pull the flywheel cover, or is it part of the engine mount?????

Marlin275
09-09-2007, 04:25 PM
I think at this point I have to ask my engine builder why this happened
and as I remember he said he used one part from my old engine
this must be it
with all that rust from 14 months from installation?
5-6 months of weekend use?

gcarter
09-09-2007, 04:36 PM
Goood luck with it.

MOP
09-09-2007, 09:28 PM
First get a tap and very """carefully""" run it into the cranks shaft threads, make sure the are decent the last thing you need is a buggered thread. Buy new bolts do not even use the old ones to check the crank threads. I have been through this a few times with several ass end mounted engines and PTO's on the commercial stuff. Take the pulley set off when you get ready to put it back on, use a little blue LocTite on clean threads and bolts and do a 3 step torque triangle pattern.

Phil

Marlin275
09-09-2007, 10:06 PM
I emailed the photos I posted here to my engine builder
he said it could be repaired in the boat
and will take care of everything
so I'll give his assistant all this great expertise
and see if they concur
Thanks for all your help
Donzi Brothers!

mrfixxall
09-09-2007, 10:10 PM
I emailed the photos I posted here to my engine builder
he said it could be repaired in the boat
and will take care of everything
so I'll give his assistant all this great expertise
and see if they concur
Thanks for all your help
Donzi Brothers!


make sure he doesnt over torque the bolts,,60 ft lbs max or it will distort the rear main seal serface and it will start leaking oil...it fell off because theirs no locttight on the bolts:bonk:

Marlin275
09-30-2007, 11:01 AM
Thanks Guys for all your help!
My engine builder got the new bolts to seat with no problem.
I was out yesterday and she ran great!
Two mechanics and the yard manager said they had never seen this happen before.