Power Loss-gctid354621

[Guest]

During the past few years the performance of my 1996 Bayliner 3388 with 150 turbo diesels has slowly but surely deteriorated to the point at which it is not possible to reach 3,000 rpm at WOT. This situation persists even when the bottom and props are perfectly clean and the boat is lightly loaded.

The engines currently have about 850 hours useage and the props, which were supplied by Premier Propellors, Bremerton in 2006, are 20 X 21 (port) and 20 X 20.2 (Stbd).

I would appreciate any advice from members regarding an appropriate course of action. For example..... valve adjustment, fuel injection/timing overhaul and adjustment, etc. etc?

Thanks in anticipation.

Jim

[p91473]

Are these the Cummins 4 cylinder 250hp? I think they are.

[ksanders]

First step is to verify the accuracy of your tachs.

Second make sure your throttles are reaching the engine throttle stops.

[Guest]

npyne wrote:
During the past few years the performance of my 1996 Bayliner 3388 with 150 turbo diesels has slowly but surely deteriorated to the point at which it is not possible to reach 3,000 rpm at WOT. This situation persists even when the bottom and props are perfectly clean and the boat is lightly loaded.

The engines currently have about 850 hours useage and the props, which were supplied by Premier Propellors, Bremerton in 2006, are 20 X 21 (port) and 20 X 20.2 (Stbd).

I would appreciate any advice from members regarding an appropriate course of action. For example..... valve adjustment, fuel injection/timing overhaul and adjustment, etc. etc?

Thanks in anticipation.

Jim

you say that your boat has 150 turbo(hino i presume). if that is true then the props should be,nakashima) 17x16 ,4 blade

[Guest]

I know I'm new here and to boating but we have several pieces of snow plowing equipment that are diesels and if they run pretty much the same way (which I would think they would) first I would check the basics, see if its getting enough air, air leaks in hoses etc. We had a skid steer tractor go down twice this year due to clogged air and fuel filters. Diesel fuel any more is garbage imo, where as a few years ago you could get away with changing the fuel filters once a year if that depending on usage but now a days we're replacing them 2-3 times a season.

[Guest]

Sorry I missed stating that the engines are Hino model W04C- 150HP.

I am surprised that Ken1954 recommends 17 X 16 4-blade props for my Bayliner 3388 because Premier Props selected 20 X 21 and 20 X 20.2 NIBRAL Class 1 uncupped based on 15,000lb dry weight, 18,000lb loaded weight and Hurth gearbox ratios of 2.04.1 stbd and 2.10.1 port with counterclockwise port rotation and clockwise starboard.

The Premier computer program indicated 20kn and the Michelin Wheel program indicated 18kn at WOT. When the props were initially installed we achieved 18 kn at WOT with clean props and bottom and since that time the performance has slowly deteriorated.

For the record the original props that came with the boat were mis-matched 4-blade 20 X 16 and 20 X 16.5. I changed them because the boat performance led me to believe that it was under-propped.

Jim

[Guest]

In reply to ksanders - thanks for the suggestion, however, the tachs have been checked OK and the throttle cables reach the maximum stops.

Jim

[Guest]

[QUOTE]npyne wrote:
During the past few years the performance of my 1996 Bayliner 3388 with 150 turbo diesels has slowly but surely deteriorated to the point at which it is not possible to reach 3,000 rpm at WOT. This situation persists even when the bottom and props are perfectly clean and the boat is lightly loaded.

The engines currently have about 850 hours useage and the props, which were supplied by Premier Propellors, Bremerton in 2006, are 20 X 21 (port) and 20 X 20.2 (Stbd).

I would appreciate any advice from members regarding an appropriate course of action. For example..... valve adjustment, fuel injection/timing overhaul and adjustment, etc. etc?

Thanks in anticipation.

Jim[/QUOTE

[Guest]

You should change your fuel filter primary and secondary and check for water in the small canister on engine.My max . rpm is 3025 with 20x18 nibral 4 blade

[ksanders]

npyne wrote:
In reply to ksanders - thanks for the suggestion, however, the tachs have been checked OK and the throttle cables reach the maximum stops.

Jim

OK, Good

Since we have a original good WOT RPM, with the props you have on there, then that isn't it.

Something has changed over the last few years.

We're assuming you change your filters regularly.

Have both engines had approx the same drop in WOT RPM, or has one engine had a significantly larger drop than the other? (trying to isolate the problem to one engine)

This is going to sound stupid, but have you added weight or aerodynamic drag to the boat? (trying to see if its your engines or something external)

[p91473]

What RPM @ WOT can you get in neutral/no load?

Can you freely spin the turbo roters with no restriction?

Have you inspected your exhaust risers? Clogged riser will slow you down.

Is there any smoke at WOT?

Have you checked the engine alignment?

Have you ever pop tested your injectors? I believe they need a rebuild at 600 hours.

Have you ever re-torqued your heads?

Have you ever checked your injector timing?

Things to consider...

[Nikko]

20 X 21 (port) and 20 X 20.2 (Stbd) at 3000 rpm. Sounds like a lot of prop for 150 HP. Are you sure those numbers are correct?

For reference, I'm running 150hp+ and spinning 17x17's and can hit 3000 rpm...

[Chief_Alen]

Engine Won't Reach Operating RPM. Check

1. Fuel condition. Type and Octane possibly old fuel

2. Propeller pitch or diameter, damaged blades

3. Restricted fuel pickup tube or anti siphon valve Fuel System Test

4. Crankcase oil volume, high oil level can cause aerated oil and lifter collapse

5. Marine growth on hull and outdrive

6. Wrong gear ratio in outdrive

7. Restricted carburetor air intake (clogged flame arrestor)

8. Restricted exhaust system (broken exhaust shutters/flappers) in engine transom shield or drive

9. Poor cylinder compression Compression Test

10. Carburetor defective, or wrong type.

11. Fuel pump pressure and vacuum

12. Boat overloaded, improperly loaded, or improperly trimmed.

13. Engine Overheating

14. Engine timing and ignition system operation

15. Remote control cables and linkage for proper travel to open throttle plates fully.

Above copied and pasted from another website Don s is the author.

Above is a good list to start.

[Guest]

Yesterday I received a computer analysis from Osborne Propellers Ltd who are the leading experts in the Vancouver Area. Based on the assumption that the engine power has reduced by 5% over the years (i.e. 143 available HP per engine) and a boat weight of 18,000lbs, their recommendation was for 4 blade Nibral 20 X 20 (port) and 20 X 19.5 (Stbd). Their estimated top speed at 3,00rpm WOT is 18.8kn drawing 143HP per engine and a 12kn cruise speed would be achieved at 2,215rpm drawing 69HP per engine.

This analysis compares favourably with those provided originally by Premier Propellers and Michigan Wheel and the 20 X 18 X 4 blade Nibral being used by Mr. Louis Kimpton.

Many thanks to those members who have taken the trouble to offer excellent and constructive suggestions.

Jim

[Nikko]

Interesting and good info - thanks for sharing. I may have to take a run down to Osbourne....