mikegalbicka
Back in the saddle again
How about a quick explanation of how that happened on a bike that had been running fine for those that didn’t see the article.
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Matt P's Flywheel Issue
- Thread starter pauls1150
- Start date
How about a quick explanation of how that happened on a bike that had been running fine for those that didn’t see the article.
pglaves
#13338
The starter just put in the bike was a Frankenstarter. It was a Valeo. Valeo makes starters for both Airheads and Oilheads. But the Airhead starter is located ahead of the flywheel ring gear and the Oilhead starter is located behind it. So to turn the engines over in the same direction the starter motors spin in opposite directions.
The Airhead and Oilhead drive heads are different but the electric motor portions are identical except for the direction that they spin. Somebody unbeknownst to Matt had erroneously mated an Oilhead starter motor to an Airhead starter drive head. So when installed in this Airhead engine it spun the engine backwards.
As I wrote above, I would not have thought of this in this lifetime or the next one.
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mikegalbicka
Back in the saddle again
Thanks Paul. That is definitely one of the strangest stories I have ever heard related to any engine maintenance. Troubleshooting for expected failures is hard enough. Troubleshooting for something like this is like the Twilight Zone. Kudos to Matt!
Counter-rotation (of the propeller) in marine engines is achieved in the gearbox. With twin engines, the engines are identical, only the gearbox is counter-rotating. So starters would be interchangeable. There must be some missing details to this story.
Cranking any starter too long on an inboard marine engine can result in hydrolock when raw water pumped through the heat exchanger fills the exhaust riser but fails to be expelled due to lack of pressure from combustion gases. It overfills then drains back through the exhaust manifold resulting in hydrolock. This is a far more likely explanation for what occurred.
lkraus
New member
Using twin marine engines with cranks rotating in opposite directions is actually pretty common with inboard shaft drive as the torque reactions cancel.
Okay. I'm not familiar with that approach, so stand corrected. In my experience it's not the engine crank, but the gear cases that creates the reverse rotation of the propeller.
Ha ha. Yup, I’ve experienced those happy days many times over. The word “boat” is actually an acronym. B.O.A.T. - - Break Out Another Thousand
But 70% of Earth is covered in water, so if you want to really see the world a boat is your best bet. That, and there is nothing quite like a long reach in the tradewinds. So well worth it.
stevenrankin
Active member
Best day
Yep, my best day was getting rid of my boat. Never had problems with it but grew to hate pulling it on a trailer, backing in and out of the garage/driveway/boat ramps.
When I get to the point were I can't get a leg over a motorcycle, I may buy a boat again. But it will be a trike or sidecar before that happens. Oh yes, I have a 335i convertible better than any boat. St.
Yep, my best day was getting rid of my boat. Never had problems with it but grew to hate pulling it on a trailer, backing in and out of the garage/driveway/boat ramps.
When I get to the point were I can't get a leg over a motorcycle, I may buy a boat again. But it will be a trike or sidecar before that happens. Oh yes, I have a 335i convertible better than any boat. St.
I bought a used Lund years back. I had to do some fixing on it, but it was in pretty nice shape when I sold it for much more than I paid for it, and I believe, over all, I made money on the deal. I remember crunching the numbers and after four years of use it didn't owe me a dime, even counting the gas I ran through it.
I was never a big boater. Don't swim, I might water ski about once every ten years. Pulled the kids on a tube some, but really don't miss it, don't see ever buying another one.
I was never a big boater. Don't swim, I might water ski about once every ten years. Pulled the kids on a tube some, but really don't miss it, don't see ever buying another one.
Now that its a boat thread
I had a co-worker who was given a boat that had sunk and needed both inboard engines (350 chevy's) replaced. He bought 2 new replacement motors (1 was counter rotating) and in his back yard replaced both motors. It took a few weeks of part time work but he got it done and had a great fist day on the water. Due to a pending tropical storm he had the boat hauled out and returned to his back yard. The storm passed and a few weeks later it was time to return his boat to the water for some fun. Unfortunately when the boat was hauled out and stored in his yard the hull drain plugs were not removed, the boat was completely full of water. He ended up rebuilding both motors, both out drives and replacing most of the electrics. He sold the boat at a significant loss after the repairs.
I had a co-worker who was given a boat that had sunk and needed both inboard engines (350 chevy's) replaced. He bought 2 new replacement motors (1 was counter rotating) and in his back yard replaced both motors. It took a few weeks of part time work but he got it done and had a great fist day on the water. Due to a pending tropical storm he had the boat hauled out and returned to his back yard. The storm passed and a few weeks later it was time to return his boat to the water for some fun. Unfortunately when the boat was hauled out and stored in his yard the hull drain plugs were not removed, the boat was completely full of water. He ended up rebuilding both motors, both out drives and replacing most of the electrics. He sold the boat at a significant loss after the repairs.
“Sinking” on the trailer or blocks is a common neophyte mistake. Boating magazines and insurance bulletins are always reminding owners about the dangers of this phenomenon.
Maybe your co-worker was highly experienced and just had an oversight. Anyone can have a bad day.
But I see loads of people get into (and out of) boating who never take the time to learn fundamentals. They end up being a menace to themselves and others on the water, at the ramp, trailering on the highway, etc. They are lucky if it only hurts their pocketbook.
Back to "non boat" discussions...I'm having trouble connecting the dots here. The basic probably after reading some of the early posts was the the timing mark was showing up at the wrong spot in the rotation, so I guess engine running...or maybe just turning by hand...and the ignition fires at the wrong time.
Where does the starter come into all of this? When checking timing on my bike, the starter is not part of the troubleshooting.
Where does the starter come into all of this? When checking timing on my bike, the starter is not part of the troubleshooting.
stevenrankin
Active member
Non boat
Hey Kurt,
Since I am lazy and have not gone back and re read the threads here I am not certain but I think it all has to do with Matt's mystery bike problem he talked about in his article.
Turns out the solution was a change of starter. The original cause of malfunction being a once in a life time or very high odds thing to happen.
LOL, one more and my last boat story. Someone I know (not me but someone close) left his boat in the driveway on the trailer with the drain plug in. As it was my house, it came to pass I had to move said boat to remove snow and found I could not move the danged thing, it weighed a ton! When I removed the cover to see what the heck was going on, I found it had filled all the way to the gunnels with water which had then frozen solid. Mind you this is just an aluminum boat with an outboard, nothing fancy but, all of his rods, tackle boxes and gear that was in the boat was encased int one big boat shape block of water. Come the the thaw the only damage done was to a little battery he used to run his fish finder and the fish finder was not in the boat.
Okay, my last boat story. Enjoy the day, St.
Hey Kurt,
Since I am lazy and have not gone back and re read the threads here I am not certain but I think it all has to do with Matt's mystery bike problem he talked about in his article.
Turns out the solution was a change of starter. The original cause of malfunction being a once in a life time or very high odds thing to happen.
LOL, one more and my last boat story. Someone I know (not me but someone close) left his boat in the driveway on the trailer with the drain plug in. As it was my house, it came to pass I had to move said boat to remove snow and found I could not move the danged thing, it weighed a ton! When I removed the cover to see what the heck was going on, I found it had filled all the way to the gunnels with water which had then frozen solid. Mind you this is just an aluminum boat with an outboard, nothing fancy but, all of his rods, tackle boxes and gear that was in the boat was encased int one big boat shape block of water. Come the the thaw the only damage done was to a little battery he used to run his fish finder and the fish finder was not in the boat.
Okay, my last boat story. Enjoy the day, St.
stevenrankin
Active member
Sorry Kurt,
Hey Kurt, from what I remember, the bike had fallen over, hydro locked and done some damage. Matt repaired all things needed to get the bike back into running order and found when he cranked the bike over it would not start. Of course at that point, he began checking the basics and If I recall, with a timing light could find the mark.
I can't quote from memory his statement in this month's magazine in regard to dodging the bullet by cranking an airhead engine in the wrong direction but suffice to say, they won't run back wards.
Kurt, you know how lazy I am, LOL, do you really want me to dig up the original article? To be honest, it made for interesting reading, and as I said, a once in a lifetime problem perhaps a huge odds thing. Makes me wonder if after solving the problem Matt didn't go out and buy a lottery ticket. LOL.
Alway a pleasure writing back and forth with you. St.
Hey Kurt, from what I remember, the bike had fallen over, hydro locked and done some damage. Matt repaired all things needed to get the bike back into running order and found when he cranked the bike over it would not start. Of course at that point, he began checking the basics and If I recall, with a timing light could find the mark.
I can't quote from memory his statement in this month's magazine in regard to dodging the bullet by cranking an airhead engine in the wrong direction but suffice to say, they won't run back wards.
Kurt, you know how lazy I am, LOL, do you really want me to dig up the original article? To be honest, it made for interesting reading, and as I said, a once in a lifetime problem perhaps a huge odds thing. Makes me wonder if after solving the problem Matt didn't go out and buy a lottery ticket. LOL.
Alway a pleasure writing back and forth with you. St.
St -
I certainly understand that when cranking, the bike would not start if it's turning the wrong direction. But again, if checking for spark at the S-mark, the starter is not part of the equation. I certainly recall that Matt did everything to ensure that the bike was correctly assembled...sans starter. But it seems to me that when you're checking for proper timing, that's all done in a static fashion...again, no starter. Wouldn't he have done static checks to say that the bike is timed right, but then when using the starter it wouldn't run? I don't recall him attempting to bump start the bike...again timing is known correct with his checks...at that point I suspect that the bike would have started. And the only thing that was not part of bump starting...is the starter.
Still not clear how the starter fouled his diagnosis up unless it has to do with "assuming" the starter was correct and the bike wouldn't start with it.
Matt doesn't post here, so our only insight is through the ON. I believe he still might be posting on the Airheads email list...but I'm only 3-4 years behind!
I certainly understand that when cranking, the bike would not start if it's turning the wrong direction. But again, if checking for spark at the S-mark, the starter is not part of the equation. I certainly recall that Matt did everything to ensure that the bike was correctly assembled...sans starter. But it seems to me that when you're checking for proper timing, that's all done in a static fashion...again, no starter. Wouldn't he have done static checks to say that the bike is timed right, but then when using the starter it wouldn't run? I don't recall him attempting to bump start the bike...again timing is known correct with his checks...at that point I suspect that the bike would have started. And the only thing that was not part of bump starting...is the starter.
Still not clear how the starter fouled his diagnosis up unless it has to do with "assuming" the starter was correct and the bike wouldn't start with it.
Matt doesn't post here, so our only insight is through the ON. I believe he still might be posting on the Airheads email list...but I'm only 3-4 years behind!
pglaves
#13338
He was checking the timing with a timing light while the engine was cranking -backwards.
This would have the timing light fire at the point in rotation where the points normally close instead of where they normally open.
guenner
Member
How in the world could this engine be started with the reversed starter? If the motor could really be started reversed then the motorcycle goes backward. But I don't think the ignition point would allow the motor to run.
So, how could the owner even have it started and running before ditched in the water?
Did he always had to push it on since a new starter was put in?
And Matt tried the starter and it didn't start, removed the plugs and checked the timing using the starter?
Something important to the story has not been told, yet!
/Guenther
So, how could the owner even have it started and running before ditched in the water?
Did he always had to push it on since a new starter was put in?
And Matt tried the starter and it didn't start, removed the plugs and checked the timing using the starter?
Something important to the story has not been told, yet!
/Guenther
