CClassic28 (Chris ?)

[CC28_NJ]

Chris,
I posted this question here Just incase anyone else had the same questions, or if they possibly have an interest in the same thing. Since our last 6 months have been blown away (No Comment), I forgot what you had said. I have pretty much have the same boat as you, same setup. 2001 though.
Tower, Genny, 4BTA's, AC/Heat, etc. Boat, needless to say is very heavy for the little guys (Engines). You had said that the ACME's were the way to go, Much better over the Hy-Torq's. Planeing, running correct RPMS's WOT etc. My question is since we pretty much have the same setup, northeast conditions, etc, Is it worth taking the Plunge for the ACME props. I talked to Bill at ACME, and he said he would machine me the props, same as yours, I just want to be sure from all your sea trials, trips , that you are satisfied with them, and do they make that much of a difference.
(Not to ramble on)

Main Problem
Mine is not getting 3000. At best I'm getting close to 2900 RPM, and I need prop work, Black smoke getting on plane, and in rough weather not seeing anywhere close to 3000, more like 2500. Everything else on engines are ok, but after many hours of reading this site and Boatdiesel, I'm convinced It needs new props.
Just wandering your thoughts.

Thanks,
Nick

[CClassic28]

4BTA performance

Nick,

Have your current props been scanned recently? If not that is where I would start and you then can keep those as spares. I tuned my stock Hi-torq props to 17 x 20.5 rather than the 17 x 21 from the CC factory. The boat from the factory is slightly overpropped for a tower & genny boat especially if you run "heavy" with alot of gear as I do.

With the Hi-torqs @ 17 x 20.5 I was turning 3025 ish RPM with full fuel, full water & gear... Now with the Acme's I'm turning 3050 RPM, full fuel, full water & gear... (acmes are 17 x 20 with .075 cup)

I would first confirm that your current RPM isssues are prop related by tuning your current props and then work from there. I am by no means a diesel mechanic but if you find the boat running @ 2500 only in a heavy sea it doesn't sound as if it could only be a prop issue.

If there is anything else I can help you with please ask away and keep me posted on your progress.

Good Luck,

Chris

[CC28_NJ]

Thanks,

I've been going over everything on the engines, and they seem to be fine, I'm going to go over the sea water pumps today, I order new impellers from Tony Athens, Port engine steams more than the starboard, So I could have a slight aftercooling issue. Not sure. I had Cummins Mech go over it and he said all is well, Did have problems with that engine, A while back it had a head gasket leak, but whoever worked on it when they put it back together stripped the exhaust manifold bolts, so it never had a good seal, that leaked and caused all kinds of soot in the engine room, Motors still ran great though. (Only ran it like that 20 miles to get home, Mech said it was not a major issue), So after that I did a turbo flush to try and do a quick clean and it seems to work ok. The funny thing is the port engine get the closest to 3000. I ordered a phototach, so I'm going to check them out this weekend. See where I stand, But I know it's over propped, When I bought the boat they had the props scanned, but as far as I know, they were never turned down,

As for only turning 2500, That bothered me, I was heading out sunday into some pretty ruff stuff 3-5's head sea, and that is all she would do, so I back it off to about 2200, and just stay on plan, 20 kts. But Even in the roughest sea I should see the props turn better I thought. Anyway on the ride home, the seas laid down and I was able to turn back up, I figured it was external force from the curret or something like that. I'll figure it out, and keep everybody posted.

(By the way, probably one of the best boats I've ever ridden in rough seas, only that I been on that compares is a 58 Buddy Davis. That says something, and I've been on a lot of different boats. Love them Carolina Boys.)

[biteme]

250 cummins

i had nothing but trouble for 2 full seasons with these engines.

[Split Decision]

Lots of black smoke is a air issue. My father had a slight exhaust leak on his cummins 250 6 cyl that he did not know about. I pluged up the aftercoolers to the point that he could'nt even get on plane and tons of smoke. If you had that much soot in the engine room, I would suspect the same thing. This would keep the turbos from working like they should.

He removed them and poured acid through them to clean them out. He might of used Mary Kay but not sure. They were plugged pretty good. After that you could hear the turbos really wind up and jumped on plane.

I would definatly give them a look.

[CC28_NJ]

Thanks guys,
Aftercoolers are on my list of things to do, Other than that I like these little engines, Very easy to work on, Yes they are underpowered for this boat, but I can live with that as long as they run. I'm 6'1, 200 and I can crawl around them fairly easily, could not do that with 330's. Having access to fix things is important to me, not just power, altough it would be nice, but everything is a tradoff.

Nick