Be easy on me please. Total newbie.

[hondaslave1342]

Just picked up a free 1990 searay 180 4.3 for free from neighbor. Been sitting for several years now. I don't know anything about boats but knowledgeable on automotive applications. I have correct mercury manuals hopefully. #7 and stern drive #6. Engine serial number 0C762406 Mercruiser 175, with alpha gen1
Neighbor said he hit a sandbar and is now clunking from stern drive. I have not started it yet.
What would you recommend on proper sequence on seeing what issue is? Drain lower unit and fire up? Any help is greatly appreciated.
Matt Chattanooga Tennessee

 

[jimmbo]

Welcome to iboats
First, this should be in the Mercruiser section, I have notified the Mods, and they will move it.

Sand usually yields to Propeller Blades, Rocks not so much.
Did the generous one, mention if the clunking changes when forward or reverse is selected? Did it change if the drive was tilted up/down?
Drain the Oil from the drive, and look for metal in it.
I, would then pull the Drive, and check the double U-joint, for signs of damage. If he hit the Sandbar at speed, and the Drive kicked up, the Double joint isn't designed for operation at High Angles, combined with High Rpm. You can then also rotate the Input Shaft, feeling for roughness and/or Binding. Repeat in Forward and then Reverse.

 

[docmirror]

My vote is; Remove all six spark plugs, put it in fwd gear. Get a socket, ext and long breaker bar on the front crank nut and turn it over two times by hand. May get an idea of where the clunk comes from. While it's in gear, try to move the prop forward and backward by hand. If you can turn it twice without too much nasty resistance, then use the starter and crank it a few times, see if you can isolate the clunking to the U joint area behind the starter ring, or the top of the outdrive. The bottom of the outdrive won't be engaged if you have it in N. A helper with a hand on the various parts would be helpful for feeling the clunk. More than likely you'll be pulling the leg anyway.

 

[Scott Danforth]

being a 1990 searay that sat. I would seriously do some test drills on the transom and stringers prior to worrying about the motor. my guess is that the boat will need about $5k worth of hull restoration long before you have to worry about the motor.

 

[jimmbo]

The most expensive boat a person can have, will likely be the one that was Free

 

[Bondo]

My vote is; Remove all six spark plugs, put it in fwd gear. Get a socket, ext and long breaker bar on the front crank nut and turn it over two times by hand. May get an idea of where the clunk comes from. While it's in gear, try to move the prop forward and backward by hand. If you can turn it twice without too much nasty resistance, then use the starter and crank it a few times, see if you can isolate the clunking to the U joint area behind the starter ring, or the top of the outdrive. The bottom of the outdrive won't be engaged if you have it in N. A helper with a hand on the various parts would be helpful for feeling the clunk. More than likely you'll be pulling the leg anyway.

Ayuh,...... That, is a sure fire way to strip out the crankshaft,....
Don't do that,....

Jumper the starter, or tighten the belt, 'n use the alternator,.....
Anything but the crankshaft bolt,.....

 

[rickasbury]

The most expensive boat a person can have, will likely be the one that was Free

This is true oh wise one!

 

[rickasbury]

And if the hull is trashed, then the motor may be the only thing of value- which might cover your disposal fees the dispose of the hull-
If you want to get into boating I would suggest putting your money into a used boat. The lots are starting to fill back up here in florida as well as rv's. Deals on used from everyone buying during the pandemic will soon be on the market.
If it were me I would gracefully back away from this- it could be a diamond in the ruff but if you don't have the experience going into this....

 

[rickasbury]

Ayuh,...... That, is a sure fire way to strip out the crankshaft,....
Don't do that,....

Jumper the starter, or tighten the belt, 'n use the alternator,.....
Anything but the crankshaft bolt,.....

Interesting reply but I don't understand your reply...if we are ingaging the starter system, why don't we start with the key? How do you energize the starter without going through the selonoid (if that's what your saying) and what are you jumping on an alternator?

 

[Bondo]

Interesting reply but I don't understand your reply...if we are ingaging the starter system, why don't we start with the key? How do you energize the starter without going through the selonoid (if that's what your saying) and what are you jumping on an alternator?

Ayuh,..... The key won't work with the drive in gear, so jumpering the solenoid will turn the motor over, without power to the ignition,.....

To manually turn the motor over with a wrench, you tighten the belt, 'n use the nut on the alternator,....

 

[flashback]

Regular maintenance is crucial on these guys so you need to get the back story on it's life. Soak up as much as you can from the knowledge base here. You will probably find that even if the hull structure is okay there will be a bunch of stuff needing attention.. good luck!

 

[Bt Doctur]

Or remove the drive first, then beg,borrow,make a T bar using an old shaft to turn the motor

 

[stresspoint]

Just picked up a free 1990 searay 180 4.3 for free from neighbor. Been sitting for several years now. I don't know anything about boats but knowledgeable on automotive applications. I have correct mercury manuals hopefully. #7 and stern drive #6. Engine serial number 0C762406 Mercruiser 175, with alpha gen1
Neighbor said he hit a sandbar and is now clunking from stern drive. I have not started it yet.
What would you recommend on proper sequence on seeing what issue is? Drain lower unit and fire up? Any help is greatly appreciated.
Matt Chattanooga Tennessee

start by chucking a new or known good battery in the boat.

get some fresh fuel to the carb , drain the tank or hook an external tank to the where the hose from the tank locates.

put some muffs on the intake and turn the water on.

crank it up and see if it fires.

if it fires up take a video with good sound of the clunking .

post vid here so as the guys can take a listen.

you can evaluate if its viable to keep going with it once it is a runner.
yea, the hull might be wasted or it may not be , some simple tests will soon decipher how good or bad the hull is.

 

[docmirror]

Ayuh,...... That, is a sure fire way to strip out the crankshaft,....
Don't do that,....

Jumper the starter, or tighten the belt, 'n use the alternator,.....
Anything but the crankshaft bolt,.....

50 years of experience says otherwise. The bolt is a grade 8 fine thread and is torqued to 60Ft/Lb. The bolt in the crankshaft will likely support double that or 120ft/lb before any thread damage is possible. I guess, if one is a gorilla and gets a 2' breaker bar it and wails on it, then it could be done. I'm going to 'assume' that one would stop before 120ft/lb or so. The idea to remove the plugs so there's no compression resistance and can go gently to find out where there's a blockage. It's not like there's a reason to go forcing it around, as it's already broke, so just get an idea of resistance.

If one is really worried about it, here's the specific tool that goes on the crankshaft snout specifically for turning it to do timing, etc.

2-In-1 S/B Chevy Engine Rotating Tool & Balancer Bolt/Washer

This dual-purpose hardened steel tool serves a both a rotating tool and balancer retainer. It simply fits into the harmonic balancer on Small Block Chevys and provides a positive way of rotating the engine (in either direction) when setting valves, locating TDC or degreeing cam. It is...

www.speedwaymotors.com

Gee, looks just like the crankbolt and fixed thick washer.

 

[Scott Danforth]

NEVER turn a SBC or BBC motor from the crank bolt. it will strip out the crank threads.

even trying to turn the motor over during a rebuild without heads can result in stripped threads.

the only method of turning a SBC, BBC or one of the derived V6's is with a crank shaft socket. Never turn them by the crank bolt.

Crankshaft Sockets - Free Shipping on Orders Over $109 at Summit Racing

Find Crankshaft Sockets and get Free Shipping on Orders Over $109 at Summit Racing!

www.summitracing.com

even available at home depot

Sunex Tools 1/2 in. Drive Sm Black Chevy Crankshaft Turning Socket SUN10000 - The Home Depot

This is a crankshaft turning socket. It is 1/2 in. drive. It is designed for use on a small block Chevy.

www.homedepot.com

 

[Grub54891]

50 years of experience says otherwise. The bolt is a grade 8 fine thread and is torqued to 60Ft/Lb. The bolt in the crankshaft will likely support double that or 120ft/lb before any thread damage is possible. I guess, if one is a gorilla and gets a 2' breaker bar it and wails on it, then it could be done. I'm going to 'assume' that one would stop before 120ft/lb or so. The idea to remove the plugs so there's no compression resistance and can go gently to find out where there's a blockage. It's not like there's a reason to go forcing it around, as it's already broke, so just get an idea of resistance.

If one is really worried about it, here's the specific tool that goes on the crankshaft snout specifically for turning it to do timing, etc.

2-In-1 S/B Chevy Engine Rotating Tool & Balancer Bolt/Washer

This dual-purpose hardened steel tool serves a both a rotating tool and balancer retainer. It simply fits into the harmonic balancer on Small Block Chevys and provides a positive way of rotating the engine (in either direction) when setting valves, locating TDC or degreeing cam. It is...

www.speedwaymotors.com

Gee, looks just like the crankbolt and fixed thick washer.

Welp. In my 50 years experience I’ve seen three that stripped the threads out. Not by me but it still can happen. The best way to avoid this is to just not do it.
now let’s get back to helping hondaslave.

 

[docmirror]

Three - in 50 years. Check. I think my favorite alternate method I saw evidence of some big azz pipe wrench tooth marks on the front V pulley once. lolz

So, turn the engine over by hand(somehow) and check for the location of the banging.

 

[todhunter]

I, too, am a slave to the almighty Honda, reside in Chatt, TN, and am named Matt. Weird. I would do as Stress point suggested.

 

[tank1949]

The most expensive boat a person can have, will likely be the one that was Free

Former owner just avoided $$$ trash fees!

 

[hondaslave1342]

Nothing wrong with the hull. Boat is in pristine condition for it's age.

being a 1990 searay that sat. I would seriously do some test drills on the transom and stringers prior to worrying about the motor. my guess is that the boat will need about $5k worth of hull restoration long before you have to worry about the motor.