Getting Acquainted with my Blackman

[Old Blue]

Is probably the right prop. I have a 23 Albacore Special which is the express model of the 23, it does not have the flybridge and is probably a few hundred pounds lighter than your billfisher.

I also have the AQAD40B which is the 165 hp motor. Mine is hooked up to the old 280 outdrive. I currently run No Slacks old prop off of his 23 Billfisher w his old 280 outdrive. Excepting the flybridge and some gear our boats are fairly comparable. So far I'm getting about 2 - 2.5 kmpg per trip. Below are some numbers that I cut and pasted from an old post when I was trying out a few different props. I think you should look for the causes of the lost power / rpms before repropping. Stuff like making sure the controls are pulling the throttle lever on the injection pump all the way open and the notorious rust flake obstruction in the exhaust elbow and or the turbo boost pressure as well as the other stuff already mentioned.

Hope this helps.


"Put her back on the trailer and switched over to Mikes old 16 X 17. I had thought that mike and I were running the same prop back when he had his 280 single prop. Fact of the matter is, mine was not an "elephant ear" but must have been a regular prop because it looked like Mikes had about 30% more blade area.

Headed back out and ran her again. Apparently the tide had started to flow.

2600 14.4 kt ~162 degrees outbound
2800 14.7 kt ~168 inbound 16.0 kt outbound
3000 17.0 kt inbound 18.7 kt outbound
3200 19.6 kt ~178 inbuond 20.7 kt outbound
3400 21.8 kt ~185 inbound
3600 23.6 kt full throttle inbound 24.8 kt outbound

All numbers were taken with full fuel tk and full bait tank and just myself on board. I figure this leaves me about 350 lbs shy of what I would be heading out for tuna since I would have a buddy, 100 lbs of ice and some fishing gear. Looks like the 16 X 17 elephant ear is the right prop."

[Nomad]

Fight on, USC right where they belong in the #2 spot!

[DOGHOUSE26]

Jesus Cristo Charlie, it's Monday and you're already into the Margarita Mode!

[NoSlack]

Here are a few things to look at in your search for the missing RPM.

Pull your exhaust elbow and check for obstructions in the water path. Water dumps in from the top and flows over the stainless exhaust insert. Check the slots at the bottom for chunks of rust. Any restriction in this area will cause a temp increase.



You RPM loss is most likely bad fuel and clogged filters. I think Rich put a new Racor filter unit on last year (at least I remember talking to him about one). Spin the T handle to take the lid off. If the filter looks like it has a film of mud on it, add some diesel fuel stabilizer and change the filters every 10 hours until it cleans up.

Racor filter service link http://www.bocaboard.com/forum/showt...t=racor+filter

One more obscure place to have a fuel restriction is in the mechanical fuel pump. There should be a small filter in there that most people don't know about.

[Old Blue]

And if you ever have rust on your turbo, you can bet that the other end of that exhaust elbow, where the stainless insert flares out to seal against the cast iron elbow, has become or never was sealed.

[Nomad]

Monday is Bloody Mary day. Friday is for Margaritas.