Forward adjusting collar

[Mark S]

I got into the reversing gear today to tighten the collar in an attempt to prevent my clutches from slipping in forward. Despite the rusty exterior, the reversing gear was appropriately lubricated and clean.

In touching the collar I inadvertently spun it counterclockwise and lost track of which notch the retaining pin had been screwed into. I don't know why I assumed I could finger tighten the collar -- failure to anticipate the obvious. In any event, I turned the collar clockwise to where I couldn't turn it anymore and fixed it with the retaining pin in the last available notch, making certain it went into the notch cleanly. A quick spin around the harbor revealed that I apparently did not tighten it even to where it had previously been set, as I noticed slippage at a lower RPM.

Should I be using a spanner wrench in making this adjustment?

Mark S

[smosher]

I used an open ended wrench and you want to turn it in small increments.

Make the adjustments in netural and try it each time. I don't remember
having to use alot of force to turn the adjustment nut.

Steve

[Don Moyer]

Mark,

If you make sure to position the shifting lever in the reverse direction the collar should turn very freely. Assuming you can still feel a slight detent, you're probably approximately 2 notches from where you need to be (still in a clockwise direction).

Don

[Mark S]

Thanks, Steve and Don.

I had the shifter lever in neutral at the time. Turning the collar also turned the shaft, although not proportionately to the collar, and I made my mistake in trying to readjust the shaft so the pin would remain vertical and centered. It didn't occur to me to freeze the shaft by engaging reverse.

I had bad dreams all night of expensive hauling and time consuming shaft removal and clutch plate R&R . . .

Mark S

[David Masury]

Mark, been ther and have done that. Put the trans lever in forward, snug up the collar be hand. Then put the lever in neutral and tighten the collar two notches and set the lock screw. Put the cover one and try it, you will not be off more than a notch or two. If it still slips, adjust it one notch, and try again. You may have to do this one more time, but you willnot have to haul the boat or loose nay sleep over it.

David

[sastanley]

Thanks, Steve and Don.

I had bad dreams all night of expensive hauling and time consuming shaft removal and clutch plate R&R . . .

Mark S

I thought I was the only one that had boat nightmares that kept me up all night :eek: ;)

Thanks for the post on adjusting collars..it is one item I haven't messed with yet!

[Mark S]

Shawn,

Thanks for the encouragement. I specialize in nightmares. I'll let you know how it turns out.

Mark

[Mark S]

Okay! A day in which neither family nor work intruded! Here's my report.

I got back into the reversing gear today. I took Don's suggestion and put the drive into reverse once I rotated the shaft so that the retaining bolt was at top and center. The collar was a breeze to move. Once again, I lost track of what notch the retaining bolt had been in so I guessed and moved it to what I think would have been two notches tighter from where it had been, two notches because last time I made it worse than it had been so two notches to compensate.

It was hard to get it into forward, so I backed off, playing with the shifter and linkage, to where it felt right. During these adjustments I found that I have a bad shifter cable. The end of the sleeve between the reversing gear lever and the U bolt that anchors the cable floats on the cable so there is no restraint to focus the cable's force onto the reversing gear lever and keep the cable from expanding sideways. A quick trip to the hardware store for some seizing wire and I was able to jury rig an assembly to keep the end of the sleeve where it belongs.

We motored out of the harbor and were able to maintain 5-6 knots at about 1600 to 1700 RPM. I noticed that giving the engine more gas was just that -- no increase in engine or boat speed at all. However, there was no slippage and had the collar not been adjusted tightly enough there would have been slippage.

I've seen other threads where this symptom as arisen, namely, advancing the throttle has no effect on engine or boat speed. I'll have to study them to see what others have done. It seems to me that this is no longer a reversing gear problem. The clutch plates don't slip and I don't see how adjusting the collar too tightly could result in this symptom. I think the collar is just about in the right place because I have the best detent I've ever had and the engine powers the boat as well as it always has in our ownership. I haven't replaced the temperature gauge yet so I'm still using the "touch" method of gauging engine temperature and it appears to be operating at the same temperature as always. The drive train seems to be just fine. When in neutral the shaft turns easily, requiring only one hand to move it.

As a result of this analysis, I'm thinking the two blade propeller reaches its maximum efficiency at that engine speed and simply won't turn any faster.

End of story for now.

Mark S

[roadnsky]

We motored out of the harbor and were able to maintain 5-6 knots at about 1600 to 1700 RPM.
I noticed that giving the engine more gas was just that -- no increase in engine or boat speed at all.

I'm thinking the two blade propeller reaches its maximum efficiency at that engine speed and simply won't turn any faster.

Mark-
Getting 5-6K at 1700RPM is just about as good as it gets!
Chances are you've reached hull speed at this point. With an Indigo Prop and some serious fine tuning you might get another 1/2 knot or so,
but it sound like you've solved your Reversing Gear issue...;)

Congrats!
-Jerry

[lat 64]

Mark,

Hope it works out good for you.
I'm taking mental notes of this thread to help fix my boat problem.
With my slipping clutch, I had lots of trouble when I tried to motor upwind in a good chop. Maybe that would be a good test for your outfit.

Cheers,

Russ

[Mark S]

Jerry, hull speed is about 6.5 knots. I've never been able to get past 6 knots because before the adjustment the clutches slipped and after the adjustment all I do is give the engine more gas with no corresponding increase in engine speed or boat speed. Just what kind of serious fine tuning did you have in mind? Another prop might make a difference, but I think you have other tricks you're thinking of.

Russ, we did well against 15-20 gusting to 30 yesterday. There was no slipping at all. We didn't make more than 5+ knots, however, and I don't feel as though the engine has a lot of power in such situations.

Mark S

[roadnsky]

Just what kind of serious fine tuning did you have in mind? Another prop might make a difference, but I think you have other tricks you're thinking of.

Mark-
Nope, no super tricks in my quiver...
I meant fine tuning using the new prop and keeping the A4 in top condition.
Sorry to infer there was a primrose path to follow.:o

Sounds to me after yesterday's 15-30 "beat", you've got your issue beat!
-Jerry

[Mark S]

Okay, Jerry. Hope springs eternal and I'm fresh outta ideas. I'm thinking new propeller for next spring. Maybe we can get a serious dialogue going here about the various alternatives -- Indigo, CDI, something called Performance Props (which may be CDI under another name), or anything else. Seems to me Indigo rates high among the community but a company that says don't put zincs on your shaft makes me wonder . . . .

Mark

[lat 64]

Mark,
I would get a vacuum gauge and watch it while I open the throttle all the way. I think it should show a drop as the throttle plate continues to open even if you don't get more power_I don't know?

6.5 kts is maybe a theoretical hull speed from the drawing board. Do you know what others like your boat can do?
But you can be right, some times you can just feel it's not pulling right like you say.

Russ

[Mark S]

Russ,

You're right -- 6.5 knots is the theoretical hull speed. We've reached it and even exceeded it slightly under sail, but we've never been able to get past 6 knots under power.

I'm not sure what useful information I'd get from a vaccuum gauge. Before the adjustment, I could power up to 1800 RPM and get 6 knots, and at any higher RPM the clutches would slip. Now I get 6 knots at a slightly less RPM, probably due to the elimination of all clutch slippage, but I can't increase the RPM's. I'm sure this is a mechanical issue external to the engine; I'm thinking propeller.

Do you see a flaw in this analysis?

Mark

[sastanley]

Mark,

(engine)
Any growth on the propeller? I am discovering that even a thin coating of marine 'friends' makes a huge difference in the behavior of the engine..it makes it very difficult to troubleshoot, as it often produces the same symptoms.

I got up the nerve to scrape my prop this weekend (I can sit at the top of a mast all day, but I get claustrophobic under boats) :rolleyes: - I was able to muster 4 dives down to the prop and get each blade pretty clean and then a quick swipe at the rest of the shaft with my trusty plastic scraper. I'd say about 85% removal, and it made a difference. I only had small pebble sized barnacles but prior to cleaning the engine was running poorly and would not run well above about 1,500.

It now goes to 1,700 but applying additional throttle above that produces a poor running engine that starts to miss and choke and sputter. So, I think I still have some sort of problem. I also am of the theory that there is a limit to how fast the engine should be able to run, the hull speed of the boat, its weight, coupled with the load on the prop and that's just it...no faster..But I think in both of our cases, that should be more than 1,700. A few weeks ago, I was able to run at 2,150 RPM. If I 'gun' the motor from a standstill (getting away from a breeze-on dock situation this weekend) it jumps to 2,000-2,100 RPM, but as the boat builds speed (about 10-15 seconds), the motor RPM drops and it starts to miss & sputter & run poorly. Reducing throttle back to 1,600 RPM or so, and she immediately stops missing & losing RPMs and appears content. In the creek in 5 knots of wind, I can happily putter around at 1,500 RPM, but some day I will need all 2,150 RPM and a motor that will run well at that speed. I am afraid to run it hard again as it never runs well at that speed. I don't know if your symptoms are similar ? I am stumped too :confused:

(prop)
I am also interested in the prop discussion. The Indigo I think would be the best motoring prop for an A-4, but I still worry a little bit about dragging around a 3-blade prop when I am sailing. My question is, can you still choose to put a zinc on with the Indigo if you want to and scrape the growth? Why would I want my prop to only last 10 years?
I am also considering a Martec folding, even though I do not race this boat. I have the original 2-blade propeller on my Catalina 30, so I think it is a 12" x 7".
The CDI urethane prop is an interesting concept because it's designed for its blades to flex and reduce pitch at high RPM. Neat idea, but I hope I don't whack a piece of flotsam with my plastic prop! :eek:

[Mark S]

Shawn,

I don't think there's any growth on the prop apart from maybe some slime, although we did launch in mid-May. Last October at haulout, the prop was very clean, although clearly aged, so I don't think we have barnacles or anything like that. I probably should have painted it this spring.

We don't have any bad running engine symptoms above 1700 RPM. At 1700, I give it more gas and that's all that happens -- we burn more gas than we need to. There's no increase in boat or engine speed. So we don't share your symptoms. I think the prop reaches its maximum efficiency at that RPM and it simply won't turn any faster due to combined engine and water resistences.

If that is so, I'm looking for a prop that pushes a little less water per revolution to get us up to 6 knots at higher RPM so that the increased engine power available at RPM's higher than 1700 can be tapped.

Do you see any flaw in this analysis? Does anybody? Don?

Mark

[sastanley]

No, not necessarily any flaw..when I can get it to run well, 2150 seems to be my max RPM...after that more throttle has no effect.

What is the size of your prop & weight of the boat? I am at 10,200 lbs. & a 12" x 7"- 2 blade. I haven't tested my speed with a GPS yet, but I think my knotmeter reads a little low..I've never motored faster than 5.1 or 5.2 according to it.

[Marian Claire]

Shawn your description sounds OOOO so familiar without the backfire. “Persistence Pays” Sorry to get off subject. Dan S/V Marian Claire

[Mark S]

We have a 1969 Pearson 35 of 13,000 lbs. displacement being pushed by a 12x7 two blade propeller which is either original equipment or made to original equipment specs. I suppose we are a little underpowered with a 1980 30 horse A4 auxiliary, but we try to sail as much as possible and use the engine only when absolutely necessary. Besides, I love the A4 and I know nothing about diesels. My speeds come from a GPS unit as my Datamarine log has just stopped working. Another thing to tweak!

Mark

[sastanley]

Mark, Do you have the old Datamarine 5000? My step-father has one of those on his Tartan and it is a weird beast!

[Mark S]

I don't know which one it is. When I turned it on Friday the LCD display read "0.0" even though we were moving right along. It stayed there all day. The unit gets electricity but does not measure anything. Impeller problem, I guess. Maybe I jostled something loose when I was in the reversing gear. The GPS is a decent substitute, but it gives you speed over ground and what I wanted Friday, after dealing with the adjusting collar, was speed through the water.

Mark