Starter motor

[ArthurWood]

Started my Merc 7.4ls the other day; port OK, but stb made a horrible racket, but started. After shutting both down, I thought I'd restart the stbd one to see if it made the same noise again. All I got was a whirring sound.
I happened to have a spare starter which I bought for a Bahamas trip a few years back, so having perused the engine manual, I thought it looked easy to replace the faulty one. Imagine my surprise when I removed the old one and saw that there were no splines on the wotsit wot engages with the flywheel! They had disintegrated. Not being a mechanic, I had no idea where they might have ended up, so I thought it prudent to ask the local Sea Ray people where the bits might have gone, before I started with the new one. "Oh, they're probably in the bottom of the bell housing or in the bilge." says he. "It'll probably be OK, but if it makes a racket, turn it off quickly." So I installed the new one, held my breath and bingo, all is well. I feel quite chuffed with myself so I might go for a little cruise tomorrow, the forecast being for 81F and sunny. (I've just got to rub it in /forums/images/graemlins/smile.gif)

 

[cliff]

Then there is the question of the damage to the flywheel ring gear and the damage it will do to the new starter motor dog.
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"Artificial intelligence is no match for natural stupidity"
sailroom <span style="color:red">The place to auction your previously loved boatie bits</span>

 

[Mal113]

If I were you I would start again and inspect the flywheel ring gear for damage to the teeth, this can be done by turning the engine over by hand and inspect the teeth via the starter motor fixing port.

Then comes the question of the debris, your Sea Ray people were correct it would be in the housing. However, if any of those pieces foul the flywheel and/or start gear you will have a major problem with possible flywheel damage, which would be very expensive to repair. I suggest you use a magnet on the end of a flexible (spring like) extension and find all the debris. The magnet can be purchased from any good tool shop.

 

[cliff]

[ QUOTE ]
If I were you

[/ QUOTE ]Why me? my ring gear is fine /forums/images/graemlins/smirk.gif
--------------------

"Artificial intelligence is no match for natural stupidity"
sailroom <span style="color:red">The place to auction your previously loved boatie bits</span>

 

[mtb]

oh

but then once we get to a certain age our ring gears start to get iffy so he may have a point LOL

 

[Kawasaki]

Re: oh

I suggest the best way to test ones ring gear. Would be to indulge in a seriously fierce Vindaloo and several Lagers/Beers and pehaps a bottle of wine.
This pre test should take about 2 hours. Best completed at about 23.00 hours.
The result of the test will be satisfactually complete and the result will become clear at about 07.00 hours the following morning.
The completion of the test is not quite so inviting as the pre test but it definately works.
The pre test does need some control. too mutch enthusiasm performing the pre test , can lead to a certain amount of lethargy / irritation and completion can last a little longer + a few visits to the completion area are required.

 

[Kawasaki]

Lot's of bell housings have a plate you can remove .
For inspection and timing etc.
As said, a good idea to get a magnet in there somehow to attract the swarf and stuff .
Don,t know owt about your engine.
You don,t want foreign bodies swilling about in there I do know that.
Similar happened to a friends Volvo. Unfortunatley He did not check the starter ring. He just stuck a new starter on but the teeth on the ring where dodgy.
Second starter damaged+ this time the crank seal suffered damage too.

Good advice to try and "clean" the bell housing.

 

[ArthurWood]

Thanks Kawasaki and others for your advice. 'spose I'd better take the starter off again to be on the safe side. I could only see a few teeth on the ring when the starter was off and they were OK. There is no obvious plate to remove on the bell housing and I can't get to the bottom as everything is so tightly packed in there - it's a V-drive, by the way.
How would I turn the engine over by hand? Thanks again.
Yours, less chuffed with himself /forums/images/graemlins/smile.gif

 

[Mal113]

If you can get to the front of the engine put a socket on the bolt holding on the crankshaft pulley and turn it with a T-bar or ratchet in the direction of normal rotation. If the engine can be decompressed then decompress it to make turning easy. If you cannot turn the engine at the crankshaft pulley then uses a bar (crowbar) and lever the engine over via the starter motor port by engaging the bar into one of the ring gear teeth. Mark the ring gear first with a chalk mark so you know the start/finish position. Reference the magnet, this type of tool is only around 8mm diameter and so should pass down past the flywheel to the bell-housing base. DO NOT enter a magnet on a wire or string for fear of it being lost.
QED

 

[ArthurWood]

I removed the starter and was able to turn the ring gear witha big screwdriver through the starter hole. No damage to the teeth. With a magnet on the end of a 24" telescopic rod I probed around down as far as I could, but only found minute particles of swarf.
On looking at an exploded view of the bell housing, I see it is not open at the bottom, but there is a plate which can be removed. How the heck I can reach the bolts is another question. Another guy at the Sea Ray dealer says I would have to hit a very big wave to have bits fly up into the flywheel, but who knows? I've now moved on to replacing exhaust elbow gaskets for a change of scenery /forums/images/graemlins/smile.gif

 

[Mal113]

As with many pieces of equipment fitted to boats, cars etc, there was little too no thought of how maintenance would be easily undertaken when in the design stage. I suspect the inspection plate is within millimeters of the hull or behind some rib so access is impossible, it is sometimes possible to make special tools to remove such items but only you can be the judge of that. If you have tried to remove the pieces of broken starter you have done your best. However, I am not sure I agree with Sea Ray about needing a big wave, what happens if you are running up over the crest or down into the though of a wave the attitude of the boat would move the pieces towards the flywheel. Some inspection plates have a magnetic plug does yours? If so it will hold the debris in situation.

 

[ArthurWood]

Replaced all 4 exhaust elbow gaskets successfully.
Returned to starter issue and started engine. At idle the transmission has always rattled but at high idle I could hear another rattle sounding like it was coming from the engine, so I wonder if ther is somethong rattling about in the bell housing. I can see the inspection plate, but I'm too big to get to it, so I'll call a small mechanic I know next week. Thnks for your help.

 

[ArthurWood]

Just a final follow-up. Small Brazilian captain/mechanic got the bits out today. Thanks again for your help.