Re: 1987 V20 with a 1990 Yamaha 150
 

Dirk - Welcome to the site!! Just a heads up on the pre saltwater series yamaha's (before 93) in case you're not aware of this issue already. They are great motors . . . but the shift shafts will fail from corrosion. If you start having problems getting in and out of gear . . . this is where to look. Also check the battery harness for hard spots.

common problems with the v20 are drain plugs in the floor, fuel fill and vent hoses, and the plastic rod rack inserts. Everything else seems to hold up really well.

http://www.wellcraftv20.com/gallery/...0031_sized.jpg

Re: 1987 V20 with a 1990 Yamaha 150
 

To answer your question . . . it depends on what prop, the condition the prop and motor, and whether or not the outboard is set at the correct height. The stock 17pitch aluminum Yamaha prop 14" x 17 and yamaha 150 will push the steplift around 40. This estimate assumes the condition of the motor and the prop are in good shape and the height of the motor is set correctly. If you mess around with different props, you can go faster. I've been told that you should prop that motor at 5500rpm WOT.

Re: 1987 V20 with a 1990 Yamaha 150
 

Dirk, my Honda 150 is cruisin' 42-4400 rpms about 30-32 mph...WOT is 6000 @ 42 mph....

Re: 1987 V20 with a 1990 Yamaha 150
 

DIRK: great to have on board. Post some Pics. of your
V-20 !! :D
Cussler Fan myself.

Re: 1987 V20 with a 1990 Yamaha 150
 

Thanks for all the replies. It seems that you guys are really informed about this boat. I have talked to Steve over in Fla. at Wellcraft and he is going to send me a copy of the plans for this boat. Where is the second HIN number? Is it under the rub rail? Also, on the Yamaha...I have heard that the shafts are subject to the onslought of the brine. Maybe a good idea to keep on in the shop. Oh, by the way anyone have an idea on the gear ratio of the 1990 Yamaha 150, not sure on the "engine family name". I I have spoken to some of my outboard guys and they tell me that NGK standards are the plug to burn in this outboard. It also looks like just judging from the bulkhead that this boat was laid with a pre-fab stringer/grid system. I guess I won't know till I get the plans, do you guys have an idea? Since I can't and won't pull the liner. Thanks guys for the welcome!

Re: 1987 V20 with a 1990 Yamaha 150
 

Dirk - We'd all love to see plans for the boat if you get them. MJ or I can fix you up with a gallery account for posting pictures. I'm 99% sure that the yamaha gear ratio is 1.86:1.

This link might interest you.
http://www.wellcraftv20.com/cgi-bin/...3042;start=2#2

Dunno . . . where the second HIN is located or too much about the construction. There are some pics in the gallery section of vic's v20 he tore the floor up, so you can see the stringers.

http://www.wellcraftv20.com/gallery/...loor.sized.jpg
http://www.wellcraftv20.com/gallery/...hase.sized.jpg

Re: 1987 V20 with a 1990 Yamaha 150
 

NGK Plugs should be called NFG Plugs :( Those plugs are crap especially after being in saltwater. Go with Champion or AC Delco Iridium Plugs for the best if you want to spend the money. The Iridium's are the best on the market but are around $10 and up each.

Here's the ones I put in my Corvette and they made a 100% difference in the running of the car.

http://www.densoproducts.com/results...artNumber=IT16

http://www.densoproducts.com/productImages/3/5325.jpg

Re: 1987 V20 with a 1990 Yamaha 150
 

man, he just wont leave the plug thing alone will he?

Re: 1987 V20 with a 1990 Yamaha 150
 

I posted this for Dirk before i posted the other topic for people's info if ya noticed the dates*>:(

Re: 1987 V20 with a 1990 Yamaha 150
 

HUH?