Starter spinning but not engaging the flywheel.

John Medina · May 2, 2012

I have a 2001 4.3GL Volvo with a SX(M) drive. With no warning or irregular sounds, my starter just stopped engaging the flywheel, therefore not turning the motor over. I pulled the starter and replaced it with a used started that had just been pulled and was working, although not great and had the same result. I took my original starter to an auto parts store and had it bench tested. Bendix appeared to work properly not under a load. I inspected the portion of the flywheel and there was no obvious signs of wear or any teeth missing. I am completley stumped. I have considered replacing the starter relay but hate to just start swapping parts and costing myself alot of extra money. I did load the boat and bring it back to the house and charged the battieries for good measure and attempted one more time, same result. I did read a post where Hydro-lock was a problem but I removed one spark plug and did not see any obvious signs of water in the cylinder. Do I need to remove all the spark plugs to check for water? Any advice would be greatly appreciated.

Don S · May 2, 2012

Re: Starter spinning but not engaging the flywheel.

Charge your battery, low voltage can do that.

John Medina · May 3, 2012

Re: Starter spinning but not engaging the flywheel.

I am charging them again for good measure. Battery read 12.8 volts before charging but I don't have any way of testing under a load at the house. I will report back my findings. Thanks for responding so quickly.

John Medina · May 4, 2012

Re: Starter spinning but not engaging the flywheel.

Both batteries fully charged and still no joy. Could a neutral safety switch or starter relay cause this problem?

Scott Danforth · May 4, 2012

Re: Starter spinning but not engaging the flywheel.

is the starter grinding? or just spinning without engaging?

if you were hydro locked, the starter would engage, and just not turn over the motor. if it was the neutral switch, the starter would do nothing.

John Medina · May 4, 2012

Re: Starter spinning but not engaging the flywheel.

The Starter is just spinning without engaging at all, it does not move one pully or belt, even if I turn the ignition key for 10 sec.

Scott Danforth · May 4, 2012

Re: Starter spinning but not engaging the flywheel.

then you most likely have a bendix issue, or a weak solenoid. make sure all your connections from the battery to the starter are good (remove, clean, re-install, then varnish). if the problem exists, replace the starter solenoid.

John Medina · May 5, 2012

Re: Starter spinning but not engaging the flywheel.

I will not be able to get back to work on the boat until Monday but I will report back. Thanks for all the helpful advice. I also read to not reuse starter bolts. I have purchased new ones but could that be an issue as well? The starter does not seem to move while turning though.

biggziff · May 5, 2012

Re: Starter spinning but not engaging the flywheel.

Try running the starter by shorting it with a screwdriver instead of using the key. If you had the same behavior with 2 different starters than it has to be a bad solenoid mounted in the boat.

Maclin · May 5, 2012

Re: Starter spinning but not engaging the flywheel.

A starter solenoid usually refers to the electromagnetic-mechanical unit (also referred to as the Bendix unit in homage to the earliest and most widely acccepted vendor/manufacturer of said device) inside the starter that, when energized, shoots the starter gearshaft out so the gear can engage the flywheel teeth. When de-energized the spring pushes it back into the starter away from the flywheel. If the starter spins freely and very fast and no grinding is heard then the "Bendix" unit is not working. If the starter spins but not as fast as one would think it should with no load then there is probably a voltage supply problem with bad conections, cables with wicked up corrosion that is hard to see, bad grounds, etc.

biggziff · May 5, 2012

Re: Starter spinning but not engaging the flywheel.

Sorry...wrong term...meant to say starter relay as other than wiring that may be the only thing common to the problem. I suppose it's possible that 2 starters each have bad bendix, but more likely wiring (low voltage due to poor connection) or some other electrical component like a relay.

John Medina · May 9, 2012

Re: Starter spinning but not engaging the flywheel.

All connections cleaned and reinstalled. Found bad ground above starter on back of the block and bad ground on one of the batteries' neg post. Pulled all the plugs, they needed replacing as well. Turned motor over with all plugs out and got about half a cup of water out of the middle cylinder. I did not know that cutting your engine could cause a problem if you were still moving. I guess I had two problems. Now what to do. I have the starter issue fix, thanks to some great advice. Now some much needed advice on what to do to make sure my engine is free of water? I can't thank all of you enough. This forum probably saved me hundreds if not a thousand or more.

biggziff · May 9, 2012

Re: Starter spinning but not engaging the flywheel.

John Medina said:
All connections cleaned and reinstalled. Found bad ground above starter on back of the block and bad ground on one of the batteries' neg post. Pulled all the plugs, they needed replacing as well. Turned motor over with all plugs out and got about half a cup of water out of the middle cylinder. I did not know that cutting your engine could cause a problem if you were still moving. I guess I had two problems. Now what to do. I have the starter issue fix, thanks to some great advice. Now some much needed advice on what to do to make sure my engine is free of water? I can't thank all of you enough. This forum probably saved me hundreds if not a thousand or more.

At a minimum I'd change the oil and filter. Inspect the oil to see if it appears milky. If so you'll want to change the oil until you no longer see any milky color. I'd dump some oil into the cylinder that had water in it and rotate the engine by hand to be sure the oil coats the piston, rings and cylinder walls. If you can get a bore scope I'd have a look in the cylinder to see if there is a lot of rust.

Good luck.

John Medina · May 12, 2012

Re: Starter spinning but not engaging the flywheel.

I do not have access to a bore scope but the little water that did come out of the cylinder did have a faint rust tint to it, do I need to be concerned? I plan on changing the oil before I start the engine. After I change the oil once, would it be ok to run the motor for a few minutes to heat the oil before changing it again?

John Medina · May 13, 2012

Re: Starter spinning but not engaging the flywheel.

Ok, plugs out my motor turns over, plugs in motor not turning over. There was a small amount of water in my oil maybe about a half a quart of oil came out looking milky. I feel like I am back to square one. I plan on taking a battery out of my vehicle and trying that, but had the same issue when I used jumper cables from my vehicle to the boat. Anything is worth a try at this point. Turning the motor over with the plugs out provide enough of a load on the starter for me to eliminate it as the culprit? Any advice is much appreciated.

biggziff · May 13, 2012

Re: Starter spinning but not engaging the flywheel.

John Medina said:
Ok, plugs out my motor turns over, plugs in motor not turning over. There was a small amount of water in my oil maybe about a half a quart of oil came out looking milky. I feel like I am back to square one. I plan on taking a battery out of my vehicle and trying that, but had the same issue when I used jumper cables from my vehicle to the boat. Anything is worth a try at this point. Turning the motor over with the plugs out provide enough of a load on the starter for me to eliminate it as the culprit? Any advice is much appreciated.

Until you properly load test the started you cannot eliminate it. You should have a local auto parts house that can load test the starter.

John Medina · May 14, 2012

Re: Starter spinning but not engaging the flywheel.

Had starter load tested and it failed. There was a plastic gear inside that was completely stripped. Gear replaced, boat started and ran like a top. Now all I have to do is make sure no more water and I will be back on the water for memorial day weekend. Thanks to all for the much needed advice and guidance.

Do those 12 v oil pumps do a good job or should I just drain the old fashion way and clean up the mess.

Scott Danforth · May 15, 2012

Re: Starter spinning but not engaging the flywheel.

I have a small pump that chucks in the drill, one manual pump (with check valves), and one home made pump/1/2hp motor combo. the little pump that I chuck on the drill is used the most because it was cheep (harbor freight), works great and only takes a few moments to finish.

SteveMcD · May 17, 2012

Re: Starter spinning but not engaging the flywheel.

If your boat is in the water, the water might be coming from your exhaust. If you crank the engine enough, and no exhaust to blow out the water, it WILL get past the exhaust valve. Get enough, and it will convert your engine into scrap. I would take out the raw water impeller until it is running again.

Don S · May 17, 2012

Re: Starter spinning but not engaging the flywheel.

SteveMcD said:
If your boat is in the water, the water might be coming from your exhaust. If you crank the engine enough, and no exhaust to blow out the water, it WILL get past the exhaust valve. Get enough, and it will convert your engine into scrap. I would take out the raw water impeller until it is running again.

No way that can happen. Gravity and the down angle of the risers prevents water from running up hill into the engine. There is still exhaust from an engine that is cranking, it's just not hot.

Starter spinning but not engaging the flywheel.

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