Ericson 35-2;Universal 3B 20-what prop?

Leander

Member II
Ericson 35-2;Universal M3 20B-what prop?

Have searched 10 years of posts, but nothing quite addresses my question.

Considering buying E35-2. New Universal M3 20B with VERY funky installation: prop is 3 blade fixed 12 L 10 (12" diameter, 10" pitch, LEFT hand turn.) The correct prop should be right hand turn, so this boat moves forward by running the engine in reverse!

If I buy the boat, I'm going to need a prop. I would welcome any suggestions from other 35-2 owners. I am in San Diego, would like the boat to sail fast but I will not be a true racer, and would like enough power to hold my own motoring 70 miles to Catalina in a SoCal winter. Engine and drive train otherwise excellent condition.

Max RPM for this engine is 3600. Still original 3/4" shaft, central saloon engine position.

Any thoughts appreciated!! Feel free to comment on diameter, pitch of a 3 blade fixed, or on fixed vs folding. I am finding that the 3/4" shaft does eliminate some prop choices. I have studied Dave Gerr's "The Propeller Book" and my first guess is an 8.5" diameter, 10" pitch, 3 blade fixed.

BTW, when I finally get a boat, I will post my experience of looking, offering, surveying, etc in SoCal spring 2011. I have been looking at all west coast very old boats (bottom of market), E 35-2 exclusively.

Thanks to all,
Leander
 
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Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
another classic E-35-2

It's great to have a new diesel!
Odd that the prop is wrong rotation, tho.
I betcha the engine model is a Universal M3-20B,
http://www.westerbeke.com/Products/productdetailLanding.aspx?id=6
Twenty HP, three cylinder.
Should be enough for the boat, with nothing to spare.

Other E-35-2 owners should be checking in with prop suggestions.

Welcome to the Ericson ranks!

Loren
 

Leander

Member II
Correct correction: M3 20B

You are absolutely correct, Loren. Don't know why I didn't recheck before posting. The engine is indeed the M3 20B, 3 cylinder, 20 horsepower, very popular in our area.

I think I've probably read hundreds of your posts by now, all excellent!

Leander
 

ignacio

Member III
Blogs Author
Same question!

Hi all,

I'm also in need of replacing my prop and not quite sure where to begin with this one. I also currently have a fixed 3 blad prop, and will replace with the same. Also, is this something that can be done in the water by a diver?

BTW: Inboards are new to me, so I'm just getting my head wrapped around the maintenance requirements.
 
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Leander

Member II
Progress on props

Hi Ignacio,

I have made some progress on this since my initial post of 5/5/11:

1. First, I bought the boat. I am the proud new owner of Maggie B, previusly known as Aquaholic, an Ericson 35-2, built 1972 as hull #228.

2. I have learned a lot more about propellers. My first step was to ask a lot of people, including a prominent propeller shop here in greater San Diego. I have found that, although all those I consulted were friendly and have tried to be helpful, there were no certain answers and the answers I have gotten tended to contradict each other.

3. I next attacked the problem by reading. I started on this Ericson site. I have found this site to be very solid, populated by people who give thoughtful answers and no bluster. I next read Nigel Calder's "Boatowner's Mechanical and Electrical Manual". I got the impression he feels propellers are not his greatest strength. However, from both his book and this site, I was finally propelled to purchase Dave Gerr's "The Propeller Handbook" ($13.43 on Amazon). I had resisted this with the thinking "Why should I buy a whole book to answer one small question?", and also trying to resist my obsession with buying books on anything and everything.

4. The Propeller Handbook was the answer for me. For $13.43, tax, shipping, and about two hours reading, I was able to address all my questions in depth. (Much of that two hours was spent thinking about the fixed, folding, and variable pitch propeller decision).

5. In looking for specific propellers, I found that the 3/4" shaft on my boat does decrease the choices available. I have no interest in changing to a larger shaft.

6. Having had a direct look at the bottom close up, I concluded that there are essentially no clearance issues-the prop is far enough away from the rudder and the hull to ignore this issue.

7. I decided on a fixed 3 blade for this point in my boat's life, following the Most Simple and Most Cheap principles. If high performance becomes of interest in the future and I have a lot of money, I would re-look at a variable pitch prop then.

8. I attacked the pitch and diameter questions as two essentially separate problems.

9. I have estimated a working dispalacement of 12,600 pounds (1000 lb over specs, figuring 4 adults and 200-400 lb of liquids and "stuff"). I made a wild guess this would increase length at waterline from nominal 27'10" to actual 28'6"

9. Unfortunately, I do not have a final answer yet. I am at the point of getting different answers each time I work though the problem. My experience is that this calculation issue usually clarifies itself over time, taking a break and taking a fresh look.

10. Overall, quite an adventure!

Leander
 
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EGregerson

Member III
LH Prop

congratulations on your new boat. On the LH prop issue, i ran into an odd thing 2 years ago. I repowered to a volvo; and was researching folding props; an on line quote got a response from gori that their documentation showed i had a left hand prop; well I'm quite sure it's right hand (looking at it from the rear); indeed the original 2 blade is stamped RH. turns out, apparently volvo views the prop from the motor; so they say it's a left hand. This might be the reason you have an LH prop (it is stamped LH isn't it?)

I can't imagine doing 70 miles to catalina in reverse; I mean, it might be ok with the drive gear, but it just seems odd.
 

Leander

Member II
Left hand, right hand

It is stamped LH, and a direct look at the prop, the turning drive shaft, and the shift controls make it obvious that the shifter was mounted backward to accommodate a prop that turns the wrong way.

My working guess is that the new engine was put in to sell the boat to the owner I bought from; the left handed prop was the only one available, and the seller took the cheapest route possible. Some of the other details of the engine install bear this out: none of the engine gauges work correctly, there are no water temp or oil press alarms, etc. The engine alignment with the shaft looks suspect.

I will not be going to Catalina in reverse!

Leander
 
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