Need general specs

[Liv42DayOK]

Hello,

I bought a '78 and have no info on it. All I have is the hull ID. Is there a website where I gan reference the ID to get the general specs? Thanx - Sob

[DCH1]

Live For Today:

You aren't the first denizen of this board to seek out help with an older model Baja. If you poke around here, you'll find several related threads where folks asked.

The bad news: There are not and never have been owner's manuals on Baja boats. (See the Complaints board.) You only get the collection of books from Merc and other vendors. In addition, on much older Bajas (before 1989 or so) it is often tough to find so much as a decent photo.

The good news: Baja MAY have some info on older models. I'd suggest that you call their customer service and ask if they have anything on the boat. You have nothing to lose but the cost of the call. And there is a "Baja History" page on their web site. In addition, on newer models you can often get Baja to provide wiring schematics, details on the fiberglass and gelcoat used, info on how the boat was designed when you ask specific questions, etc.

By the way, what model boat, engine, drive and prop do you have?

DCH

[Liv42DayOK]

DCH,

The problem is that, neither I nor the PO know even what model it is. It's and 18' open-bow, powered with a Johnson 150, 2 stroke O/B with a 3 blade, 16 pitch, aluminum prop.

It is small, light, and sits low in the water. When on plane, the nose rides lower than most of the deeper draft vessels I've observed.

I'm looking for the appropriate prop for my use but, without the weight, model, etc., I can't use the mfgs websites for a recommendation. I use the boat primarily for tubing, wakeboarding, and kneeboarding. It originally had a 21 pitch prop but, I chewed it off on a submerged log and, the 16 pitch is what I was able to get on an emergency run to the marina on vacation.

I noticed that, whith the 21 pitch, the boat was very slow to plane but, it ran very fast at WOT. How fast, I do not know as none of the guages work. (I bought the boat and trailer for $1000. The engine runs excellent). With the 16 pitch, I can plane in a heartbeat even when towing a XXXL size person but, the top speed is greatly reduced. Not that I mind. On other than smooth water, with the original prop, WOT is like 4 wheeling without a suspension! I know shamefully little about this as this is my first boat. From what I can decipher with my limited techno-knowledge, I'm guessing that an 18 pitch, 3 blade aluminum prop may be a suitable selection? - Sob

[DCH1]

Live For Today!

The info you've provided helps a lot just to gauge your situation. Thanks! Knowing that you have an 18 foot bow rider with a 2-cycle 150 HP Johnson OB tells me a world about your boat! I'd like to zero in a bit with you. Let's start with serial numbers!

ENGINE

The odds are good that you can get the serial number off the engine. Look at the link below. If you have a really OLD boat, betcha the OB is one of these, but confirm it with the SN!

Johnson 150 HP Manuals
Year Model
1978 150TL78
150TXL78
1979 150TL79
150TXL79

Marine Engine Manuals - Johnson Outboard (http://www.marineengine.com/manuals/johnson/#top)

A Google search for "Johnson outboard serial number" will pull up a pull up a lot of these "antique" engine sites. Get a manual for it! If you want to save a buck, knowing HOW to do it yourself will keep you out of trouble. And if you have a good mechanic do it, he may not have good info on your old engine. Johnson still makes a 150 HP 2-cycle engine. You can see them on www.johnson.com.


NOSE DOWN? - TRIM SETTINGS!

If the boat runs nose-down, it is most likely because you don't have the engine trimmed correctly. There are typically adjustments on trim angle on these engines, and you should check it out. Could be that a previous owner didn't like being pounded on the water and set it down low to cut through waves.


PROP

I think you're moving down the right path here!

First off, I am NOT a prop expert. We have a propeller forum with Daren of Houston Propeller. He is excellent and is worth consulting. You needn't buy a new labbed prop to get the straight from him.

For what it is worth, my guess on prop pitch is as follows: Once you've gotten a manual for the motor you have and have figured out how to trim it out, I think you'll find that FOR TOP SPEED something about 18 or 19 pitch will work in a 3-blade prop. For wakebording, etc, a 17 pitch 3-blade should be about right. I would imagine that a 16 pitch prop is a bit too low for your boat unless all you want is hole-shot capability for pulling up two skiiers at once. In that case, a 4-blade might make some sense.

I have a 20 foot I/O bowrider with 175 HP that I run with a 17 or 18 pitch 3-blade aluminum prop, but my bowrider setup probably will not perform as well as your outboard 150 will. I have never tried a 4-blade prop on it, and so that is where my experience ends!


HULL

All boats built since 1972 have a hull ID. It tells you the maker (first 3 digits) and typically the layup date (last 4 digits). Baja is code AGC. Here is a partial list of makers.

Ohio Boat Manufacturers Hull IDs (http://www.ohioboats.com/manufacturers/)

Layup date is identified by the letter in the last 4 digits of the hull number. They run A=Jan, B-Feb, etc. My hull number has "H", telling me the boat was laid up in August. The 3 digits following tell you the year. Mine is "001" for 2001. These links won't tell you much unless there was a recall on your boat.

US Coast Guard Boat ID Web Site (http://www.uscgboating.org/recalls/mic_database.htm)

I assume with the hull number you can call Baja and get minimal particulars on the boat model and weight. But even without that, we can probably guess your weight without that if we need to, or have you drive to a truck scale!


INSTRUMENTS

Welcome to boating. Instruments are always suspect, and speedos clog frequently. They never work right.

You can usually use high pressure air on the side of the line at the speedo head to blow out the crud and get the speedo to work. I just went for a GPS speedo. Seems you want towing power more than top end and probably shouldn't do what I did. In your case if dialing in with accurate speedo readings is important to you, I'd suggest a handheld rather than a built-in, or a friendly boater with a good speedo.

Most old OBs don't have much in the line of gauges. I recall some having a fuel gauge. And they lie anyway!


Hopefully this helps a bit. Please let us know how you make out.

DCH

[Liv42DayOK]

DCH,

Thanks for the info. I forgot to mention that the motor is a 1984! I have the manual but, it covers a slew of motors from 50hp up to 275 from 1976 through 1984.
It talks in depth about general prop characteristics: pitch, cupping, cavitation, etc. but, it doesn't make any kind of specific applications for prop types as there would need to be a whole other book on it for all the engines this one covers!

Still, the serial number reference is a good start and, I do have a post in for Daren.

Without my tach and trim guage operating, I'm really flying blind on proper trim. I start with the motor all the way down, come on plane, and then lift it about half way up. It seems to me that the boat actually slows down and the engine revs higher. So I lower it, the nose comes down, and it seems to run smoother... that can't be right though, it goes against all physical properties. Of course, I don't see how the boat is actually riding in the water since I'm inside it! I perceive that the nose is lifted somewhat, not all the way down like when I'm just plowing water.

I'm hooking up with a friend in a week who has had experience with boats so he may be able to help. Thanx again for your input, I'll see what Daren has to say. I need a spare prop so, if it looks like an 18p or something would be a bit more suitable, I'll get one as my primary and keep the 16p for a spare and when I pull 2 people behind me. - Liv42DayOK!

[DCH1]

I'm beginning to think that Daren was right on his first guess about cupping . . .

Good luck!

DCH