loss of power

[bonnes dream]

I own a 2006 Regal 3560 with two 8.1 Volvo Penta v8's. it has DPS drives. a few weeks ago we were out on the boat, as we left the marina and I proceeded to go up on plane like always and I noticed my starboard engine would not climb in rpm's like the port engine did. After up on plane the starboard engine rpms caught up. the enginge runs fine but seems to have a loss in power. I changed the fuel filter, and put new plugs in both motors. I poured the fuel out of the filter into a clear glass jar and it was perfectly clean. I also run ethonal treatment in my fuel every time I fill up. I'm at a loss. Yesterday (Sunday 7/31/16) I took the boat out again and after up on plane I opened the throttles to wide open position and the rpms will not go over 3800 on the starboard engine. Port engine is fine.
Do I throw a new fuel pump on or does anyone have a better idea?
Thank you,
Mike Kapp

 

[Bondo]

Do I throw a new fuel pump on or does anyone have a better idea?

Ayuh,..... Diagnose the issue, rather than throwin' money at it hopin' it'll work out,.....

Do both motors run off the same fuel tank,..??

I'm guessin' those motors are 'puter controled Efi,..??

Probably got fuel pressure test ports, so ya can check the fuel pressure,....

I see ya threw new spark plugs into it, but how 'bout cap, 'n rotor,..??

 

[alldodge]

Howdy Mike

What are the rest of the model numbers for the 8.1, probably won't make any difference but just in case?

What did the plugs look like?

Your fuel pressure should be around 40 psi at 1800 rpm

 

[bonnes dream]

The engines run off of seperate tanks, and are multi - port fuel injection. No cap and rotor, computer controled, each cylinder has its own ignition coil. I'm not sure of the firering order but being at the rear of the engine looking forward, the left side of the engine, second cylinder back the old plug was black and wet and the cylinder behind that one was the same. The new plugs on those cylinders are a light brown after about about an hour of run time at 3700 rpms. the first one and forth one were still looking brand new. the engines are 8.1 OSI-C, 375 4012170303 A136018, 8.1 OSI - C 401167223 A130938

 

[alldodge]

Yes, the 8.1 (496) does not have a distributor, it uses a crank sensor and the ECM fires the individual coils. The best thing to do is to get the engine scanned for codes. Other then that I would suggest getting a fuel pressure reading

 

[alldodge]

Info: Your firing order is 1-8-4-3-6-5-7-2
Left side is 1-3-5-7, right side is 2-4-6-8
The two plugs which were black are 2 and 4

 

[bonnes dream]

No, the ones that were black were 3 and 5.

 

[alldodge]

Yep

 

[bonnes dream]

Just want to do a follow up post on my engine loss of power. I finally called in the profesionals! I quickly found out that my injecters needed cleaned. I had them cleaned and now the V8 runs like a brand new engine.. Thanks to all who responded.
Mike

 

[alldodge]

Just want to do a follow up post on my engine loss of power. I finally called in the profesionals! I quickly found out that my injecters needed cleaned. I had them cleaned and now the V8 runs like a brand new engine.. Thanks to all who responded.
Mike

Thanks for the follow up and glad your up and going again.

A bit puzzling from my point of view of the fix. If there was a couple injectors clogging then it would be a bit of a miss, but no mention of that. So all injectors were clogged the same amount, just unusual

Happy boating

 

[bonnes dream]

No missing, I did not get the bill to see exactly which injectors were clogged or just dirty. The guy that cleaned personally told me that it looked like they were never cleaned. I do use Star Bright ethonal treatment every time I refuel. I know this the boat runs great and those 375 horses just came alive. Had a great run this weekend from Chesapeake City to Inner Harbor for the weekend.

 

[alldodge]

If you keep your filters changed the injectors should never need cleaning with regular use. Now if the motor sat for a while and gas went bad then maybe. The only way to really clean injectors is with an injector cleaning fixture. Hooking up a can of injector cleaner by a mechanic is not a true cleaning. Shops do this for a living and can get them flow tested and cleaned by sending them out, don't know of a dealer which has one of these systems, not saying they don't, but the machine is expensive. Cost for cleaning service is around $20 an injector

 

[bonnes dream]

I change my fuel filter every season. Does it help to run an injector cleaner in the fuel like I use Ethanol treatment or is this just a waist of money?

 

[alldodge]

In my opinion, its a waste, along with kinds of additives. Ethanol fuel will soak up water, so adding some thing that does the same is a waste. If your going to lay up for longer then 6 months, it won't hurt to use a stabilizer. I don't use stabilizer unless it's going to be more then 6 months, and only if its ethanol fuel. Best thing to do is drain it.

Adding a bottle of "golly gee wiz bang" to the tank isn't going to clean injectors