I put in one of the permanet magnet ARCO starters. Next best thing since sliced bread. If you didn't need shims on your old starter, more than likely the new starter will fit fine. Might as well look at the flywheel teeth while the engine is out. Make sure the starter is made for your flywheel. There is a 12 3/4"(153 tooth) flywheel that takes the starter with the inline mounting bolt pattern. The larger 14"(168 tooth) flywheel takes a starter with a staggered mounting bolt pattern. The starter itself is the same...the nose casting with the different bolt patterns hold the starter closer or farther from the flywheel to accomodate the two different diameters.
Engine Coupler Problem?
- Thread starter myoldboat2
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myoldboat2
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A mechanic friend of mine rigged up some stuff on his press and got the old engine mount out. The new one was tough to get in--I think the hole in the housing is slightly out of round. I tried freezing the mount and warming the housing, but no luck. I eventually used a thick walled socket and some wood blocks and was able to tap it into place. There is a beveled spacer that goes in first, which allows something to press against when removing the mount--anyway, I got the mount seated against that spacer.
Talked to Arco and they said I could ground the starter body and jump to the large post and the S (start) post. Did that and it engaged and turned the engine. Sounded loud, though, but maybe it's just that it's a different starter and oil hasn't been pumped into the cylinders for a while. I didn't crank more than about a second. I thought maybe the flywheel was rubbing on the plate that mounts ahead of it, but I was able to turn the crankshaft pulley about 15 degrees and didn't hear anything. So I'm hoping there will be no surprises with the starter and flywheel.
Got the engine back in and the mounts all bolted in. Then found that the oil drain kit brass block that mounts on the bottom of the oil pan didn't have good clearance and had turned loose about 1/8 turn. So now I get to fart around taking that kit off and going back to my drain plug. I originally tried to thread the drain hose straight into the oil pan, but it kept cross threading, so I went to the brass block that came with the kit. Bad idea. I guess I will have to buy a better pump to suck the oil out in fall, or maybe rig up a funnel system with a hose out the back. Thought I had her licked with that oil drain hose kit. Dammit.
Today's first question: My gimbal bearing pivots left/right and up/down if I push sideways on the alignment tool. That's normal, right? The alignment tool goes all the way into the coupler. But it takes two hands and some wiggling to get it out. The spline grease I put on the tool shows that the top is hitting more than the bottom. So the engine/coupler would need to go up slightly. But my engine blocks access to the lower adjusting nut on the front engine mount. Also, if the front of the engine was moved down any more, the water pump pulley would hit the engine mount bolt. A prior mechanic (or maybe the boat manufacturer) had installed one extra washer on each rear engine mount to raise the rear of the engine. See this diagram:
I put those back in the way they were, and that puts me where I'm at now. So the extra question for today is, is my alignment OK? Again, the tool slides in with some force (not a lot, but not just my pinky either), then takes two hands and a little wiggling to get out. In other words, I know the alignment isn't dead nuts perfect, but I'm not sure I can do anything about it (other than add additional, thinner washers to the rear engine mount).
Thanks!
Talked to Arco and they said I could ground the starter body and jump to the large post and the S (start) post. Did that and it engaged and turned the engine. Sounded loud, though, but maybe it's just that it's a different starter and oil hasn't been pumped into the cylinders for a while. I didn't crank more than about a second. I thought maybe the flywheel was rubbing on the plate that mounts ahead of it, but I was able to turn the crankshaft pulley about 15 degrees and didn't hear anything. So I'm hoping there will be no surprises with the starter and flywheel.
Got the engine back in and the mounts all bolted in. Then found that the oil drain kit brass block that mounts on the bottom of the oil pan didn't have good clearance and had turned loose about 1/8 turn. So now I get to fart around taking that kit off and going back to my drain plug. I originally tried to thread the drain hose straight into the oil pan, but it kept cross threading, so I went to the brass block that came with the kit. Bad idea. I guess I will have to buy a better pump to suck the oil out in fall, or maybe rig up a funnel system with a hose out the back. Thought I had her licked with that oil drain hose kit. Dammit.
Today's first question: My gimbal bearing pivots left/right and up/down if I push sideways on the alignment tool. That's normal, right? The alignment tool goes all the way into the coupler. But it takes two hands and some wiggling to get it out. The spline grease I put on the tool shows that the top is hitting more than the bottom. So the engine/coupler would need to go up slightly. But my engine blocks access to the lower adjusting nut on the front engine mount. Also, if the front of the engine was moved down any more, the water pump pulley would hit the engine mount bolt. A prior mechanic (or maybe the boat manufacturer) had installed one extra washer on each rear engine mount to raise the rear of the engine. See this diagram:
I put those back in the way they were, and that puts me where I'm at now. So the extra question for today is, is my alignment OK? Again, the tool slides in with some force (not a lot, but not just my pinky either), then takes two hands and a little wiggling to get out. In other words, I know the alignment isn't dead nuts perfect, but I'm not sure I can do anything about it (other than add additional, thinner washers to the rear engine mount).
Thanks!
First of all, the gimbal bearing will rotate as in an eyeball socket but not easily. Secondly, when you put the alignment tool in the GB and coupler You have to give the end of the tool a few HARD palm slaps in different directions to help settle the alignment (that eyeball socket thingy).
Check the grease(on the alignment tool) very carefully as to the exact area where it's hitting hard. If it's hitting on the top...lower the front mounts.
I think I mentioned this before. There are DIFFERENT motor mounts. The newer ones have a knurled surface on the edge of the inner sleeve. This corresponds with difference in the placement of the motormount castings of the BRAVO bellhousing. You'll have to check it out for more info but The knurled mount doesn't use the 'double wound washer'. It uses a SS flat washer instead. You may be using the wrong mounts in the wrong bellhousing. I had to go through all this when swapping an older alpha drive to the Bravo drive.
Another thing, when checking alignment, rotate the engine 90*,180*,270* as you check. There will usually be a tight/loose spots unless everything is new. adjust to get a happy medium.
Check the grease(on the alignment tool) very carefully as to the exact area where it's hitting hard. If it's hitting on the top...lower the front mounts.
I think I mentioned this before. There are DIFFERENT motor mounts. The newer ones have a knurled surface on the edge of the inner sleeve. This corresponds with difference in the placement of the motormount castings of the BRAVO bellhousing. You'll have to check it out for more info but The knurled mount doesn't use the 'double wound washer'. It uses a SS flat washer instead. You may be using the wrong mounts in the wrong bellhousing. I had to go through all this when swapping an older alpha drive to the Bravo drive.
Another thing, when checking alignment, rotate the engine 90*,180*,270* as you check. There will usually be a tight/loose spots unless everything is new. adjust to get a happy medium.
myoldboat2
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jtybt15> First of all, the gimbal bearing will rotate as in an eyeball socket but not easily. Secondly, when you put the alignment tool in the GB and coupler You have to give the end of the tool a few HARD palm slaps in different directions to help settle the alignment (that eyeball socket thingy).
That is an absolutely perfect description of what I have!
The mechanic at the marina was really careful about looking up the part numbers. The left engine mount he came up with was the same as the number I came up with: 32832 MOUNT, FLYWHEEL HOUSING (LEFT). I compared it side-by-side to the old mount and they were identical. The mount on the right side of the housing (which was still a good mount so we left it) does look slightly different (99297A1 MOUNT, FLYWHEEL HOUSING (RIGHT)), but maybe it's just because it's not new.
OK, I have a very dumb question... how do I rotate the engine through each 90 degree range? I was able to rotate it by hand on the flywheel, but of course the housing is back on now. I suppose some tool could engage on the crankshaft front pulley. Or I could get the wires all hooked back together and use the starter. Which way do you do it?
I think my engine blocks access to the lower adjusting nut on the front engine mount. Also, if the front of the engine was moved down any more, the water pump pulley might hit the engine mount bolt. Maybe I need to take an even closer look at that area, and maybe take a picture of it to post here.
Thanks for your help on all of this.
That is an absolutely perfect description of what I have!
The mechanic at the marina was really careful about looking up the part numbers. The left engine mount he came up with was the same as the number I came up with: 32832 MOUNT, FLYWHEEL HOUSING (LEFT). I compared it side-by-side to the old mount and they were identical. The mount on the right side of the housing (which was still a good mount so we left it) does look slightly different (99297A1 MOUNT, FLYWHEEL HOUSING (RIGHT)), but maybe it's just because it's not new.
OK, I have a very dumb question... how do I rotate the engine through each 90 degree range? I was able to rotate it by hand on the flywheel, but of course the housing is back on now. I suppose some tool could engage on the crankshaft front pulley. Or I could get the wires all hooked back together and use the starter. Which way do you do it?
I think my engine blocks access to the lower adjusting nut on the front engine mount. Also, if the front of the engine was moved down any more, the water pump pulley might hit the engine mount bolt. Maybe I need to take an even closer look at that area, and maybe take a picture of it to post here.
Thanks for your help on all of this.
myoldboat2
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More progress.
First, I was confused about the front engine mount. I don't have part 46 in the June 5th diagram above. I was looking for adjustment nuts higher than that. Instead of part 46, the bolt is mounted to a cross spar on the pontoon boat. So the adjustment nuts are above and below that spar, not easy to access at all, though. Here are some pictures, but I'm not sure they show much (except how crowded it is). I realize now that an adjustment will not change the clearance between the nut/bolt and the water pump pulley.
(Do you think the spare v-belt that's zip-tied in place will be degraded at all by the heat of the thermostat housing and hoses?)
But I think I found the problem. As I was reconnecting things, I eventually got to the throttle cable and found it was pinned tight between the front of the oil pan and the angled floor of the bilge. I had to pull the front mounting bolts to free the cable, but after bolting it all back together the alignment is very good. The cable was holding the front of the engine up slightly. Now the alignment tool slides in with one good push, and comes out with one hand and a bit of wiggling, showing equal spline marks in the grease. I wonder if the extra washers were added to the rear mounts because of the way the front mount is directly on a spar. Or maybe over the years the rear transom mounts sagged and a mechanic added the washers. I don't know. I will check alignment at the various engine positions to see what I have. Now that the engine is mounted, I'm not sure if I can get a wrench on the harmonic balancer.
Next I have to try to get my arms under the engine to remove that oil drain hose and brass block, and reinstall the oil drain plug. That is not going to be fun. Do you drain your old oil or pump it through the dipstick tube?
Then I will try running the engine before I put the outdrive back on.
First, I was confused about the front engine mount. I don't have part 46 in the June 5th diagram above. I was looking for adjustment nuts higher than that. Instead of part 46, the bolt is mounted to a cross spar on the pontoon boat. So the adjustment nuts are above and below that spar, not easy to access at all, though. Here are some pictures, but I'm not sure they show much (except how crowded it is). I realize now that an adjustment will not change the clearance between the nut/bolt and the water pump pulley.
(Do you think the spare v-belt that's zip-tied in place will be degraded at all by the heat of the thermostat housing and hoses?)
But I think I found the problem. As I was reconnecting things, I eventually got to the throttle cable and found it was pinned tight between the front of the oil pan and the angled floor of the bilge. I had to pull the front mounting bolts to free the cable, but after bolting it all back together the alignment is very good. The cable was holding the front of the engine up slightly. Now the alignment tool slides in with one good push, and comes out with one hand and a bit of wiggling, showing equal spline marks in the grease. I wonder if the extra washers were added to the rear mounts because of the way the front mount is directly on a spar. Or maybe over the years the rear transom mounts sagged and a mechanic added the washers. I don't know. I will check alignment at the various engine positions to see what I have. Now that the engine is mounted, I'm not sure if I can get a wrench on the harmonic balancer.
Next I have to try to get my arms under the engine to remove that oil drain hose and brass block, and reinstall the oil drain plug. That is not going to be fun. Do you drain your old oil or pump it through the dipstick tube?
Then I will try running the engine before I put the outdrive back on.
myoldboat2
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Got the oil drain hose kit off and the drain plug back in. The alignment is very good, I think. The tool slips in and out with no effort in three of the 90 degree positions. In the fourth position, it goes in with a one hand push, and pulls out with one hand. Tighter than the other three positions, but it still feels pretty good to me. With no cooling water, I ran the engine briefly. All seems well. The new starter seems very powerful.
Next I will install the sterndrive. I don't really understand how the rubber gasket ("a" in diagram) is supposed to be installed. The old one is in there, but I'm not sure if it's still seated correctly. Should the new gasket overlap the bellows rubber at all, or does it just butt tightly against the bellows edge? All of the manuals just say to make sure it's properly positioned but don't explain what that means.
Any other tips about installing the sterndrive, other than being careful about the shifter linkage?
Also, my outdrive has fresh gear lube in it from last fall. Assuming it is still at the right level, is there any reason that storing the outdrive on its side would mean I should change the lube?
Thanks.
Next I will install the sterndrive. I don't really understand how the rubber gasket ("a" in diagram) is supposed to be installed. The old one is in there, but I'm not sure if it's still seated correctly. Should the new gasket overlap the bellows rubber at all, or does it just butt tightly against the bellows edge? All of the manuals just say to make sure it's properly positioned but don't explain what that means.
Any other tips about installing the sterndrive, other than being careful about the shifter linkage?
Also, my outdrive has fresh gear lube in it from last fall. Assuming it is still at the right level, is there any reason that storing the outdrive on its side would mean I should change the lube?
Thanks.
Sounds like you have it aligned. Boy, you sure don't have much room. Is there any way to open up the front of the bilge area?
I have never found a drain fitting that I felt satisfactorily matched the drain threads. I don't even remember what I have in there now but it's a brass fitting(pipe/flare threads???). No valve. Just a 3' hose with a 3/8 SS rod for a plug. I have the extra fan belt somewhat laying down and off to the side of the water pump but it's on a 302(ford).
On that big O ring, remove the old one and replace it. You will see a 'lip' that it butts up against. Clean that area real good. I use some perfect seal/aviation gasket sealer on that O ring but Now a days I would use a thin film of silicone.
If your oil didn't have metal fragments( as in magnectic/steel) and maybe just some aluminum flakes(like sparkles in the oil) You should be OK but it's best to store upright. Set the drive upright for a couple days, then check some of the drive oil. Do you use the synthetic(Green high performance) drive oil?
I have never found a drain fitting that I felt satisfactorily matched the drain threads. I don't even remember what I have in there now but it's a brass fitting(pipe/flare threads???). No valve. Just a 3' hose with a 3/8 SS rod for a plug. I have the extra fan belt somewhat laying down and off to the side of the water pump but it's on a 302(ford).
On that big O ring, remove the old one and replace it. You will see a 'lip' that it butts up against. Clean that area real good. I use some perfect seal/aviation gasket sealer on that O ring but Now a days I would use a thin film of silicone.
If your oil didn't have metal fragments( as in magnectic/steel) and maybe just some aluminum flakes(like sparkles in the oil) You should be OK but it's best to store upright. Set the drive upright for a couple days, then check some of the drive oil. Do you use the synthetic(Green high performance) drive oil?
myoldboat2
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> Is there any way to open up the front of the bilge area?
I don't think so. The metal bilge wall comes up just a few inches forward. The engine cover box is sized to fit the hole. Maybe someday if I redo the deck, carpet and furniture.
Next time I change the oil I'll think about finding a brass fitting and fitting it to the drain hose. I really didn't like the way that drain oil hose kit fit up, but the hose and end cap are good.
I had trouble trying to align the spare belt somewhat horizontally. Keeping it tight upward the way I have it keeps it away from the harmonic balancer. I was just wondering if you think the heat of the thermostat housing will hurt the belt's strength over time. Not sure how hot those belts are designed to run.
I have Perfect Seal I could use on the big rubber gasket. By silicone do you mean something like Permatex Ultra Black? I have that, too. I'm assuming I don't have to remove the bellows for any of this.
The gear lube was good before I laid the drive down. I will check it as you say. Yes, I use the green lube, the Mercury High Performance Outdrive Gear Lube+ 92-802854A1.
Thanks.
I don't think so. The metal bilge wall comes up just a few inches forward. The engine cover box is sized to fit the hole. Maybe someday if I redo the deck, carpet and furniture.
Next time I change the oil I'll think about finding a brass fitting and fitting it to the drain hose. I really didn't like the way that drain oil hose kit fit up, but the hose and end cap are good.
I had trouble trying to align the spare belt somewhat horizontally. Keeping it tight upward the way I have it keeps it away from the harmonic balancer. I was just wondering if you think the heat of the thermostat housing will hurt the belt's strength over time. Not sure how hot those belts are designed to run.
I have Perfect Seal I could use on the big rubber gasket. By silicone do you mean something like Permatex Ultra Black? I have that, too. I'm assuming I don't have to remove the bellows for any of this.
The gear lube was good before I laid the drive down. I will check it as you say. Yes, I use the green lube, the Mercury High Performance Outdrive Gear Lube+ 92-802854A1.
Thanks.
myoldboat2
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YAHOO!! Back together and working like a champ on the earmuffs. HURRAY!!!! Couldn't have done it without you, Charlie.
Of course now my kids are leaving town for a long weekend. So it may be a few days before I get the shakedown cruise done. Two questions:
1. Another power trim question. Every once in a long while, when the drive is all the way down (or nearly all the way) when I push the top two buttons the trim pump just clicks. I try a few times and then it goes. It did that right after I assembled everything. The battery was fully charged and the trim fluid full. Bad connections? Bad pump?
2. My outdrive is kind of loud when shifting (I shift swiftly, per George). That might be because I've got the idle set too high, about 800 rpm, but I had to do that to smooth out the vacuum reading. I had the carb rebuilt and still couldn't lower the idle much, but I'll try lowering it again. I don't want to ruin my gears, although at low idle speeds the whole boat starts jumping around--maybe it's because of those wound steel washers in the engine mounts, or maybe it will be better with the new rubber mount (I doubt it). It is louder going into reverse than going into forward. How difficult is it to adjust the dogs, and what's involved? I've never done it.
THANKS!!
Of course now my kids are leaving town for a long weekend. So it may be a few days before I get the shakedown cruise done. Two questions:
1. Another power trim question. Every once in a long while, when the drive is all the way down (or nearly all the way) when I push the top two buttons the trim pump just clicks. I try a few times and then it goes. It did that right after I assembled everything. The battery was fully charged and the trim fluid full. Bad connections? Bad pump?
2. My outdrive is kind of loud when shifting (I shift swiftly, per George). That might be because I've got the idle set too high, about 800 rpm, but I had to do that to smooth out the vacuum reading. I had the carb rebuilt and still couldn't lower the idle much, but I'll try lowering it again. I don't want to ruin my gears, although at low idle speeds the whole boat starts jumping around--maybe it's because of those wound steel washers in the engine mounts, or maybe it will be better with the new rubber mount (I doubt it). It is louder going into reverse than going into forward. How difficult is it to adjust the dogs, and what's involved? I've never done it.
THANKS!!
The gear are always turning as long as the engine is turning. The shift dogs are shoved into the turning dog teeth. That's the clunk you hear. The lower the idle, the less force is put on those rotating dog teeth as they are shoved together.
The lower shift cable adjusts how far the dog clutch travels into forward and reverse. The total travel is somewhat fixed and the clutch is slide between opposite rotating gears. Example, there is 1" total travel in the clutch. You try to adjust the travel so the clutch moves 1/2" into forward and 1/2" into reverse. The barrel nut on the shift plate does the adjusting.
It sounds like your clutch is engaging reverse more than forward. You can judge this by turning the prop clockwise in forward and counterclockwise in reverse. You will feel and hear the clunk of the dog clutch riding up and falling off the forward or reverse gear. Adjust that barrel nut so the clunk in the prop is the same in forward as it is in reverse.
(engine not running)[:I]
The lower shift cable adjusts how far the dog clutch travels into forward and reverse. The total travel is somewhat fixed and the clutch is slide between opposite rotating gears. Example, there is 1" total travel in the clutch. You try to adjust the travel so the clutch moves 1/2" into forward and 1/2" into reverse. The barrel nut on the shift plate does the adjusting.
It sounds like your clutch is engaging reverse more than forward. You can judge this by turning the prop clockwise in forward and counterclockwise in reverse. You will feel and hear the clunk of the dog clutch riding up and falling off the forward or reverse gear. Adjust that barrel nut so the clunk in the prop is the same in forward as it is in reverse.
(engine not running)[:I]
myoldboat2
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I read the manual on the shift cable adjustment, and then I looked over the shift plate. I'm not sure I get it, so I'm going to leave it for another day. I'll keep asking around and maybe someone around here can show me how to do it.
> (engine not running)
Thank you for that vote of confidence...
What do you think about the occasional clicking of the power trim system? It hasn't done it over the last few tries, but I haven't had it on the water yet.
Thanks.
> (engine not running)
Thank you for that vote of confidence...
What do you think about the occasional clicking of the power trim system? It hasn't done it over the last few tries, but I haven't had it on the water yet.
Thanks.
I never could make heads or tails out of the adjustment procedure in the manual so I figured out an easier way to make the adjustment. Try it, just slide the barrel out of it's slot and turn it in or out, which just moves the cable back and forth. Re-insert the barrel i n it's slot and rotate the prop and listen to the ratcheting in both forward and reverse. Asjust the barrel so the ratcheting is of equal intensity in forward and reverse.
The majority of the time, clicking in the tilt/trim system is from bad electrical contacts. Next time you make an order from Boatfix, order a spare solenoid. They cost from about $5 to $15.
The majority of the time, clicking in the tilt/trim system is from bad electrical contacts. Next time you make an order from Boatfix, order a spare solenoid. They cost from about $5 to $15.
myoldboat2
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HOOOOORRAAAYYYYYY!!! Had the boat out for the shakedown cruise on Tuesday. Ran like a champ. Took the kids and their friend skiing and wakeboarding. Tomorrow we take a bunch of adults out tubing and partying.
Charlie -- THANKS! THANKS! THANKS! THANKS! THANKS! THANKS! THANKS!
For he's a jolly good fellow, for he's a jolly good fellow
For he's a jolly good fellow, that nobody can deny
Which nobody can deny, that nobody can deny
For he's a jolly good fellow, which nobody can deny!
Charlie -- THANKS!
THANKS! THANKS! THANKS! THANKS! THANKS! THANKS!
For he's a jolly good fellow, for he's a jolly good fellow
For he's a jolly good fellow, that nobody can deny
Which nobody can deny, that nobody can deny
For he's a jolly good fellow, which nobody can deny!
myoldboat2
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I have a question regarding the strength of the entire drive system.
Less than a year before my (very old) coupler failed, I had a friend of mine ski behind the boat. I commonly pull kids skiing and wakeboarding, and adults and kids tubing, without issue. But when I had my 200+ lb adult friend ski, I remember hearing the engine/outdrive really bog down every time he did a deep cut outside the wake. I remember thinking that this big boat could probably use more power to pull an adult skier but didn't think much more about it. But less than a year later, my coupler splines were sheared off.
But, when I was a teenager weighing close to 200 lb, I would regularly ski behind a runabout with a 50 hp outboard. I would cut plenty hard and we never damaged the outboard.
So my question is this: What part of the system is supposed to "let go" if the drive system becomes overloaded? I don't mean in terms of the aluminum coupler splines being sacrificed before the hardened steel driveshaft splines... What I mean is, there must be something designed into the system to stop the drive from becoming overloaded to the point that the coupler fails.
Now my thought is that the prop would slip in the water before enough torque could be delivered to damage some part of the engine or outdrive. But is that the case?
I began to think about this when wondering if I should let adults ski behind my boat. The boat is pretty big and heavy and I don't want to have to replace the coupler again. But I think the reality is that the system is designed to handle the torque and the old coupler failed probably just due to age. Having an adult skier really bog down the engine/outdrive shouldn't hurt anything. Is that right or wrong?
Kind of an I/O design theory question, I guess.
Thanks.
Less than a year before my (very old) coupler failed, I had a friend of mine ski behind the boat. I commonly pull kids skiing and wakeboarding, and adults and kids tubing, without issue. But when I had my 200+ lb adult friend ski, I remember hearing the engine/outdrive really bog down every time he did a deep cut outside the wake. I remember thinking that this big boat could probably use more power to pull an adult skier but didn't think much more about it. But less than a year later, my coupler splines were sheared off.
But, when I was a teenager weighing close to 200 lb, I would regularly ski behind a runabout with a 50 hp outboard. I would cut plenty hard and we never damaged the outboard.
So my question is this: What part of the system is supposed to "let go" if the drive system becomes overloaded? I don't mean in terms of the aluminum coupler splines being sacrificed before the hardened steel driveshaft splines... What I mean is, there must be something designed into the system to stop the drive from becoming overloaded to the point that the coupler fails.
Now my thought is that the prop would slip in the water before enough torque could be delivered to damage some part of the engine or outdrive. But is that the case?
I began to think about this when wondering if I should let adults ski behind my boat. The boat is pretty big and heavy and I don't want to have to replace the coupler again. But I think the reality is that the system is designed to handle the torque and the old coupler failed probably just due to age. Having an adult skier really bog down the engine/outdrive shouldn't hurt anything. Is that right or wrong?
Kind of an I/O design theory question, I guess.
Thanks.
Increased load on any engine running freely at a constant RPM will cause some bogging from the load. How to determine if you're causing a problem is hard to determine.[:O]
Example:
After building my 406 CI engine(320 hp-425 ft/lbs torque) the first time, I was coming in after a long albacore run. The engine was freshly broken in and we were running with 8-10 ft swells and of course we bogged down on the back of them. Just for Yucks, I gave her full power going up an lo and behold, I was powering up the swells. I was having fun.
When I got back into the bay and running 3200rpm, BANG!!! Ended up breaking the upper gears.
I guess what I'm trying to say is, if you're going to bog the engines, let it bog, don't try to power out...the bogging is probably limiting the strain on your drive components.
ME...I don't hot dog anymore, gets expensive.
Example:
After building my 406 CI engine(320 hp-425 ft/lbs torque) the first time, I was coming in after a long albacore run. The engine was freshly broken in and we were running with 8-10 ft swells and of course we bogged down on the back of them. Just for Yucks, I gave her full power going up an lo and behold, I was powering up the swells. I was having fun.
When I got back into the bay and running 3200rpm, BANG!!! Ended up breaking the upper gears.
I guess what I'm trying to say is, if you're going to bog the engines, let it bog, don't try to power out...the bogging is probably limiting the strain on your drive components.
ME...I don't hot dog anymore, gets expensive.
myoldboat2
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Thanks, Charlie, that makes sense to me.
I wonder if my Late Model I stern drive is protected at all by my having just a 140 hp engine. I don't know what maximum hp rating that outdrive had. I ran the engine at full throttle while pulling the adult skier, so I wasn't able to try to overpower the bogging. It just sounded like it was hard on things.
I wonder if my Late Model I stern drive is protected at all by my having just a 140 hp engine. I don't know what maximum hp rating that outdrive had. I ran the engine at full throttle while pulling the adult skier, so I wasn't able to try to overpower the bogging. It just sounded like it was hard on things.
myoldboat2
Member
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- Jun 3, 2007
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- 26606
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- 135
Uh oh, I never should have brought up the shift cable question without knocking on wood. Now it went on the fritz. Darnit. I will start another thread.