Perkins Power

[anchorkid]

Hello to all, we are from New Zealand, have a Perkins 6.345 T in our launch, have a issue with power under way.
Revs fully when in netrual,both forward and reverse, motor makes all the right noises etc, but when we got underway,wouldnt go past about 3 knots at full throttle down and reverse.

Any advice would be greatly appreciated.

Take care out there folks

 

[Comodave]

Welcome aboard. Are the bottom and running gear clean?

 

[anchorkid]

hi there, thank you for the reply, that is one thing that has come to mind and i have her booked to bring out of water for a inspection, clean, antifoul.

many thanks

 

[Comodave]

What RPMs are you getting in gear at WOT?

 

[BruceK]

Can you describe the "launch" dimensions etc? What speed used it make? Tell us about the transition? Is there vibration?
If it`s severe and sudden, maybe something wrapped around the running gear/prop?

 

[Swa]

Possible Damper plate shot my guess

 

[roberttigar]

replace the fuel filters, both of them.Bob

 

[High Wire]

Check the RPM of the transmission output. The transmission could be slipping badly. Have a diver check the under water running gear.

 

[anchorkid]

Check the RPM of the transmission output. The transmission could be slipping badly. Have a diver check the under water running gear.

thank you, yes being hauled out next week.

 

[anchorkid]

yes doing that this weeek, thank you

 

[anchorkid]

am getting 2400 at netural wot (which is perfect apparantley), but only 1000 wot in forward .

 

[KnotYet]

X2 on the fuel filters.
Assuming there is an electric lift pump, make sure it is working, too.

 

[anchorkid]

ive done the oil, the diesel fuel filter is next, however i only see 1 filter not 2??

appreciate the assistance and advice.

 

[KnotYet]

ive done the oil, the diesel fuel filter is next, however i only see 1 filter not 2??

appreciate the assistance and advice.

Typically, you will have a main filter and a secondary filter near the injection pump
often mounted on the engine.
The engine mounted filter is sometimes overlooked but it needs regular service, too.
Cleanliness is next to godliness when it comes to the fuel system.
Clean the area really well before removing and replacing the filter(s) and keep an
eye on the various o-rings you may encounter.

 

[anchorkid]

many thanks, i shall get the manual out and sit in front of the motor and do some more study to locate the secondary filter.

have a great day and thank you so much.

 

[Island Cessna]

many thanks, i shall get the manual out and sit in front of the motor and do some more study to locate the secondary filter.

have a great day and thank you so much.

Check the air intake too. Our Perkins 4-236 has a simple wire mesh screen over the intake elbow. The PO had a long haired dog, and the screen was substantially plugged with oily dog hair.

 

[sunchaser]

As others have noted, change the fuel filters. The Perkins engines have two on engine filters. When was the last time these two and your primary filter were changed? What micron reading is your primary filter? For now, a 30 micron primary is just fine provided you're using badged Perkins on engine filters.

 

[anchorkid]

hi there, thanks for this, we can truely only see 1 main fuel filter, its a Perkins 6.354 HT engine, approx 1980ish!!, oldie yes but a goodie so far.
i changed the main filter today and bled diesel through, and she fired immediatley and certainly got more revs, just a little warm up smoke and at full throttle threw little bit rubbish out exhaust, but i never run her full throttle anyway, usually back off to around 1600/1700 in gear.

 

[twistedtree]

So it seems to be fixed now?


If you took a few pictures of the engine someone here might be able to comment on the fuel filter set up.


And just to be clear, the "primary" filter is typically mounted somewhere in the boat, and not on the engine itself.

 

[Ox76]

Most lift pumps have a screen for the inlet side to keep bigger chunks of crud from reaching the filters. I've had these plug up and cause problems when under a load. Farm background. Perkins engines.

 

[anchorkid]

yes seems to be fixed, heading out for a run this weekend so will soon see, but definatly alot better with new fuel filter.
and thanks for comment on primary filter, i shall again do a intense study and yes will take some pics to post.

many thanks

 

[anchorkid]

awesome thanks for this, might be worth a look once i find where the lift pump is, she is a big old motor,lol,lol.

 

[anchorkid]

Perkins pics attached

Hi all, have attached pics now of filters etc, also pic of what was throwing out before changing all oil,filter,and fuel filter.

 

[Solly]

1st picture is that a fuel filter directly under ( down in the pic ) from the oil filter ?? It has what looks like fuel lines in and out of it. There should be another filter somewhere off the engine. The one or two on the engine, you have to be meticulous about placing the gaskets on the filter correctly and getting it to seat.

 

[anchorkid]

yes thats the fuel filter straight down , top view obviously.

 

[anchorkid]

this is the "glass bowl" just after the fuel lines towards back of boat!!

 

[Max Simmons]

Is that a horizontal mount engine?

 

[anchorkid]

yes sure is

 

[Brooksie]

am getting 2400 at netural wot (which is perfect apparantley), but only 1000 wot in forward .

NO, 2400 should be the LOADED RPM. 3100-3150 is the no load RPM if I recall correctly (it's stamped on the injection pump tag usually)
So you may be starving for fuel, have a linkage problem, or IP problem.

 

[FlyWright]

Check to make sure your stop solenoid is not partially closed (OFF) when you think it's open (ON). I had one of mine stick and it prevented revving under load.