Jump to content
My Monterey
Russ

2005 270CR Slowing Down

Recommended Posts

I am soliciting opinions and knowledge and experience. My background is electrical engineering and I have boated many years in small craft. My boat is stock as far as I know, but I am the second owner. Here is some information about the boat.

Hull Number - RGFCC281G405

Engine – Volvo 5.7 GXi S/N 4012132996

Outdrive:

VolvoPenta

DP DuoProp

P/N 3868913

Type DP-SM

Ratio 1.95

S/N 4202116556

Info from props:

Volvo Penta Duo-Prop

Rear prop says – F5REAR 3851475 4E

Front prop says – F5FRONT 3851465 4E

props are in excellent condition

There are roughly 350 hours on the engine.

My normal use is off plane at a sedate 7 or 8 mph.

I did give it a full throttle run when I was doing the test drive. Then later again when I had my GPS and was able to coax a maximum speed of 42 mph with which I was very satisfied and probably would have no need to repeat.

Well, this past weekend I had three other folks and myself and decided to get up on plane and get to where we were going more quickly. Much to my embarassment I could not get on plane. I tried every arrangment of trimming I could think of and she jsut stayed pointed up in the air with the rpms sitting at about 2800 to 2900. I bet I kept at it for 10 minutes with no joy. I was not a happy boater.

 

I took it back out the next day alone and was eventually able to get on plane. It only seemed to finally get there when I put the trim tabs fully up and had the outdirve trimmed fully down. With the throttle wide open the best I could ever get on a perfectly calm lake was 33mph at almost 4000 rpms.

So I set to work to see if I could improve things and figure anything out. I installed a new fuel filter and tried that. No change. I installed new spark plugs and tried that. Again no change. I did a compression test and all cylindars where equal and 210 psi on my gauge. I unplugeed the connector to each fuel injector one by one and listened for and felt for a miss, and every cylindar did miss when the fuel was cut off at idle. The wires look like newz and an induction timing light gets a good flash from each wire. The boat starts very easily and seems to idel and run without a missfire. The bottom is not perfectly clean but I am not sure how significant that might be. It has been in a relativiely clean lake only 4 weeks since the bottom was clean. There is no bottom paint, just the white gel coat.

When I pull back to a cruising speed the boat seems happiest at about 3100 rpm and that gets me along at about 23mph with the trim tabs down to keep the bow from bouncing.

So, where did all the speed go from 40+mph to 30+ mph? I don't need to go 42mph, but I sure need to be able to get on plane.

It seems to take forever to get on plane now, so I timed it from full throttle application to 3600 rpm and that took about 55 seconds.

Please ask me any questions that might help you point me in the right direction. Email is russwhite @ earthlink.net with the two spaces removed.

Thanks,

Russ

Share this post


Link to post
Share on other sites

Hi there,

 

I have a few questions and i think this is where we should talk about so everyone on monterey can read about it these are the questions:

 

When you make a test drive was the tank full?

When you did not get on plane, where is everyone, on the back? on the front? and was the tank full?

was the water tank full? was the wast tank full?

your boat have trim tabs, are they fine?

Was you in a river, what was the direction off the corrent, you where going on the same side off the corrent or against it?

 

All this count when we talk about speed fresh water don´t have the impulse the same as sea water, boats can have very diferent speeds, but i agree with you not get on plane for 10 minutes something is very very wrong.

Did you tell to the dealer to make the anual proceed in the engine like change oil, filters etc...???

Did he change the current engine are the current engine to tight or to loose? have you change the candles engine ( don´t know if this is corect, i´m portuguese)?

 

Just a note i ride a 278 sc first i give full trotle so he get´s on plane, when he´s on plane i take gas, pull up a litle engine trim ( so the hull stays out off water) and play with the trims tabs normally at 25% or 30% i can go about 3100rpm on 32 mph i have a mercruiser 350Mag with a Bravo III

 

I´ll wait for your answers this i like to discuss

 

Ride with your heart

 

Marfi

Share this post


Link to post
Share on other sites

Hi Marfi,

 

Thanks for your reply and your English is so good!

 

First I will answer you questions and then add what little additional information I have.

 

The fuel tank was full. The water tank was full. The waste tank was empty.

I had two 120 lb guests on the sun pad on the bow. One 150 lb passenger near the stern.

The trim tabs are fine and I have working trim tab position indication.

I was in a lake with no significant current.

All filters are new and oil is new.

"candles" I suspect we call spark plugs. They are new.

I have purchased instrumentation to monitor the fuel pressure, engine vacuum, and timing.

The advanced timing light has not yet arrived so I am waiting for that before trying again.

I found the oil about 3/4 quart too much, so I removed and will be at the full mark next try.

Fuel pressure at idle was exactly as specified in the shop manual and increased to 59psi when vacuum line to the regulator was removed.

The bottom is now cleaned. I verified the spark plug wires are to the correct plugs.

I'll remember to post the results of my next attempt and what the instruments have to say.

Thanks,

Russ

Share this post


Link to post
Share on other sites

I am happy to report my problem has been solved. At the end of last season I changed the oil as part of the winterization proceedure. I aspirated all the oil I could get from the sump and then added the quantity recommended in the owner's manual for an oil and oil filter change.

Unfortunately for me, I did not carefully check the level in the sump. As part of the list of items to check when one has top end problems I checked the sump level and found in too high. I kept removing oil until the dip stick showed the level at the full mark. Turns out I had to removed over a quart of oil. Apparantly the too high level interfered with the free turning of the crankshaft and my engine's full power. With the level on the mark and the bottom cleaned I was again at 43.4 GPS MPH at 4300 RPM's. I'm a happy camper now!

Russ

Share this post


Link to post
Share on other sites
I am happy to report my problem has been solved. At the end of last season I changed the oil as part of the winterization proceedure. I aspirated all the oil I could get from the sump and then added the quantity recommended in the owner's manual for an oil and oil filter change.

Unfortunately for me, I did not carefully check the level in the sump. As part of the list of items to check when one has top end problems I checked the sump level and found in too high. I kept removing oil until the dip stick showed the level at the full mark. Turns out I had to removed over a quart of oil. Apparantly the too high level interfered with the free turning of the crankshaft and my engine's full power. With the level on the mark and the bottom cleaned I was again at 43.4 GPS MPH at 4300 RPM's. I'm a happy camper now!

Russ

 

Hi Russ,

 

I´m very happy to see that everything turn alright for you, it´s very sad to see someone with a boat don´t having fun because problems with the engine and other things.

 

Ride with your heart

 

Marfi

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...