Starter bolts sheared on 1994 Maxum 4.3 - Maxum Boat Owners Club

loukywells · 06-01-2016, 04:35 AM

I installed a new starter last week on my 4.3. Went out this past weekend and one bolt completely sheared off, which then caused the second bolt to break off - causing the starter to basically fall off the block. In my 25 years of being a mechanic, have I never seen this occur with any marine or auto. Called the manufacturer (Delco Reman) and he had never heard of this in his 20 years of service there. AND it then took 4 hours to remove the old bolts from the block. Could this be a defective bolt or could there be too much torque for this starter. The old starter is a Delco 9000768. I also verified the torque specs when I installed the new one. Thoughts on this as the owner of the company is sending another unit today.

mmwjr · 06-01-2016, 11:23 AM

Welcome aboard

I have heard of this before and the cause has been the bolts are too long and bottom out before the starter is tight to the engine. The torque from the loose starter causes it to twist and break the bolts. For more info from folks who have had this happen check out this on BOC.

loukywells · 06-01-2016, 06:29 PM

Hydrolocked! Pulled spark plugs and water is exiting cylinders. Sorry...what is BOC?

loukywells · 06-01-2016, 07:50 PM

Water is also in the oil. Drain the oil, took out spark plugs, sprayed WD40 in the cylinders. I assume this is caused by stopping quickly, but I just want to make sure (and quickly) that I am doing the correct things to prevent any corrosion.

ss3964spd · 06-01-2016, 08:48 PM

BOC = Bayliner Owners Club - an online forum similar to this one.

Still a little unusual for the starter bolts to shear off like that, even if it HL'd. When they HL you usually just get a click, or a clank, from the starter. Are there any hardness markings on the heads of those bolts?

Water in the cylinders could possibly be from stopping quickly, do you recall doing so? Can also be from an internal riser/manifold leak. Did water come out of all the cylinders? Water in the oil - how much? Water can get in the crank case past the rings, at the intake manifold, or from a head gasket. which cylinders had water in them, and how much water is in the crank case, may help narrow down where the actual problem is.

WD40 is ok for "displacing" water but it also a really good solvent so it will also remove oil from the cylinder walls. Chase the WD40 with a couple shots of oil then turn the crank a few times to distribute it.

loukywells · 06-02-2016, 12:24 AM

Thanks for your reply. I do remember stopping pretty hard maybe about 30 minutes before, but shouldn't it immediately stop the engine with water in it? I did hear the "clank" and attempted to start it again, but at that time - the starter just broke the 2nd bolt.

Water did not come out of all cylinders...port side was much worst. When I drained the oil, maybe a cup full of water was released. I will shoot some oil as advised. The motor was replaced 1.5 years ago and maybe has 10 hours on it. I would be very surprised if it is from a manifold leak...but you never know I guess. i just hate to put new plugs back in, replace the starter and then it occurs again.

mmwjr · 06-02-2016, 03:45 AM

As said do not use WD-40, motor oil or fogging oil.

Was the engine ever overheated? I'm thinking this is more than a rapid slowing down. Oil does not get milky that fast.

loukywells · 06-02-2016, 04:13 AM

Oh wait...ss3964spd stated to shoot some oil in the cylinders and crank it manually, which I did! Is this not accurate? The engine has never overheated to my knowledge. I have taken it out several times already this year and it ran perfect. The Vortec block was replaced 2 years ago and has been maintained very nicely as I know the family that had it before me. After I drained the oil and looked into the bucket, there was really only about a 1/4 cup of water max and it really doesn't look that milky. I'm taking it to the mechanic that has always maintained it just to get a wise opinion.

Winding Down · 06-02-2016, 05:03 AM

I have done the "broken starter bolt" thing also. Hydro locked engine caused by cracked cylinder head. ( previous owner had been starting it in his driveway without water while attempting to sell it!). Also led to broken thread hole in block. 4.3 merc. We eventually made a good runner out of it eventually, but learned that water in the engine brings nothing good!!

mmwjr · 06-02-2016, 11:58 AM

Quote:

Originally Posted by loukywells

Oh wait...ss3964spd stated to shoot some oil in the cylinders and crank it manually, which I did! Is this not accurate? The engine has never overheated to my knowledge. I have taken it out several times already this year and it ran perfect. The Vortec block was replaced 2 years ago and has been maintained very nicely as I know the family that had it before me. After I drained the oil and looked into the bucket, there was really only about a 1/4 cup of water max and it really doesn't look that milky. I'm taking it to the mechanic that has always maintained it just to get a wise opinion.

Sorry was tired when I responded, I meant to say use motor oil or fogging oil but not WD-40.

loukywells · 06-14-2016, 08:06 PM

Just an update. Changed oil (3 times), replaced plugs and oil filter....fired right up. Everything is running perfect with no water in oil now. Now what caused this hydrolock...no shutters on one side and half of one on the other side. Question now is...how do I remove what has fallen down in the "Y" or should I just leave it (don't think that I should).

mmwjr · 06-15-2016, 02:18 AM

If they are laying down the pipe they will restrict the exhaust flow. Sometimes you can remove the drive and reach into the exhaust bellows all the way and find them. Sometime you have to remove the exhaust elbow to fish for them and sometimes they break into small enough parts they pass through the system.

IMO pull the drive and remove what you can.

loukywells · 06-15-2016, 02:25 AM

Thanks MMWJR! Nothing was found (removed the elbow assembly and the outer rubber hose assembly near the transom, which means the marine company that replaced the engine a couple of years ago failed to replace. It's looks like they just removed the one side completely and just left the other damaged one as is....stupid if you ask me. Oh well, ordered them this afternoon.

shrew · 06-15-2016, 03:18 PM

You hydrolocked because:

1) You are missing at least one shutter

2) You allowed the wake to catch up to you too quickly by stopping so abruptly. The following wave forced water up into the exhaust, past the elbow and dumped water into the exhaust ports. This is particularly an issue if the engine is shut down to quickly.

The force of exhaust should prevent some of this. The shutters prevent the rest. It's best to slow down gradually. watch the speed of the wave following you. sometimes you have to give it a little more throttle to 'outrun' the following wake. If that occurs you know you're slowing down too quickly.

With a hydrolocked engine, you're lucky you didn't do any additional damage like bending a rod or breaking teeth on the starter or flywheel.

The key is not just to do an oil change, but to run the engine hot for 10-15 min. between each oil change to try and burn out any residual water.