engine y8m

[marv]

I ran my engine for about 1 hr on my cd27 this weekend and all went ok for a while .at abour 45 minutes into the run the engine rpm decreased somewhat at 3/4 throttle dropping about 20% of what it normally would be at that setting. Its as if somthing is preventig the engine from coming up to its normal setting at that throttle position.
it was as if the throtle was just cut back a bit.

when the gear was put into nuetral the rpm came back up but slowed dn again (20 %) of normal at that setting.
I never changed the main fuel filter, but changed the small in line 2hrs ago.
the water flow is ok as is the volume and clarity of exhaust water.
I have never seen any water dripping from the packing gland near the prop shaft..
I suspect either the fuel filt may need to be changed or the shaft is tight( I did touch it after running and it was cool)

any Ideas ???



mibrinn@aol.com

[kevin]

I ran my engine for about 1 hr on my cd27 this weekend and all went ok for a while .at abour 45 minutes into the run the engine rpm decreased somewhat at 3/4 throttle dropping about 20% of what it normally would be at that setting. Its as if somthing is preventig the engine from coming up to its normal setting at that throttle position.
it was as if the throtle was just cut back a bit.

when the gear was put into nuetral the rpm came back up but slowed dn again (20 %) of normal at that setting.
I never changed the main fuel filter, but changed the small in line 2hrs ago.
the water flow is ok as is the volume and clarity of exhaust water.
I have never seen any water dripping from the packing gland near the prop shaft..
I suspect either the fuel filt may need to be changed or the shaft is tight( I did touch it after running and it was cool)

any Ideas ???

Marv,
Change that other filter. Blow the fuel lines out. Including the fuel return line to the tank. Also change the air filter.

Good luck ,
Kevin



kevin_02563@yahoo.com

[Ed Haley]

My guess is that the fuel filter is clogged. You may have to filter or replace all the fuel in the tank in addition to changing filters. Do you place a biocide and stabilizer in your fuel regularly? It's important to prevent life forms from populating your fuel tank and keep all the free carbon molecules intermixed with the fuel. Usually this problem begins to assert itself after aggressive agitation of the fuel tank occurs, such as motoring through good-sized waves.



eghaley@twcny.rr.com

[marv]

I ran my engine for about 1 hr on my cd27 this weekend and all went ok for a while .at abour 45 minutes into the run the engine rpm decreased somewhat at 3/4 throttle dropping about 20% of what it normally would be at that setting. Its as if somthing is preventig the engine from coming up to its normal setting at that throttle position.
it was as if the throtle was just cut back a bit.

when the gear was put into nuetral the rpm came back up but slowed dn again (20 %) of normal at that setting.
I never changed the main fuel filter, but changed the small in line 2hrs ago.
the water flow is ok as is the volume and clarity of exhaust water.
I have never seen any water dripping from the packing gland near the prop shaft..
I suspect either the fuel filt may need to be changed or the shaft is tight( I did touch it after running and it was cool)

any Ideas ???

Marv,
Change that other filter. Blow the fuel lines out. Including the fuel return line to the tank. Also change the air filter.

Good luck ,
Kevin

Er ......the engine has an AIr filter???
no kidden where is that puppy located?
how do you replace and blow out all the fuel in the engine?
I did use a stabilizer and biocide when I topped her off this Jan.

I dont use that much fuel perhaps that is part of the pblm. i.e the fuel sits so long 4 mos that it has a chance to develope crud..
question how often should the fuel be removed and refreshed?]
how do you drain out all the fuel and "Blow the lines"?



mibrinn@aol.com

[Mark Yashinsky]

Change the large fuel filter and INSPECT THE OLD ONE. Is it clogged w/ crud (when was the last time it was changed)??? Any water??? Does the engine run the same when you lose RPM's, no missing/roughness, no smoke??? Some where along the side of the head, either next to or on the oppisite side from the exhanust (the one that goes to the muffler), is the intake (air), that usually comes from a filter (round pleated), usually in a round cover that has some sort of quick release to it. The cover has an opening to allow air to the filter. Look for it.

[Kevin]

I ran my engine for about 1 hr on my cd27 this weekend and all went ok for a while .at abour 45 minutes into the run the engine rpm decreased somewhat at 3/4 throttle dropping about 20% of what it normally would be at that setting. Its as if somthing is preventig the engine from coming up to its normal setting at that throttle position.
it was as if the throtle was just cut back a bit.

when the gear was put into nuetral the rpm came back up but slowed dn again (20 %) of normal at that setting.
I never changed the main fuel filter, but changed the small in line 2hrs ago.
the water flow is ok as is the volume and clarity of exhaust water.
I have never seen any water dripping from the packing gland near the prop shaft..
I suspect either the fuel filt may need to be changed or the shaft is tight( I did touch it after running and it was cool)

any Ideas ???

Marv,
Change that other filter. Blow the fuel lines out. Including the fuel return line to the tank. Also change the air filter.

Good luck ,
Kevin

Er ......the engine has an AIr filter???
no kidden where is that puppy located?
how do you replace and blow out all the fuel in the engine?
I did use a stabilizer and biocide when I topped her off this Jan.

I dont use that much fuel perhaps that is part of the pblm. i.e the fuel sits so long 4 mos that it has a chance to develope crud..
question how often should the fuel be removed and refreshed?]
how do you drain out all the fuel and "Blow the lines"?

Marv,
Every engine has an air filter. It should be located on the side of the engine. I am unfamilliar with the model of engine in your boat but, they are sometimes exposed foam with a metal screen over them or a paper filter in a plastic box. There are usually only 2 ways to stop a diesel engine: 1, stop fuel flow or 2, stop air flow. So one of these 2 situations is probably happening. To verify the fuel lines are clear you will have to disconnect them from the engine and run a pipe cleaner through them. It will be messy.

Kevin

[Olli Wendelin]

The Yanmar YS series engines have no air filter by design, only an intake pipe. This is supported by their tech manual.

Olli Wendelin
BLUE MOON
Charleston, SC



wendelin@spawar.navy.mil

[Mark Yashinsky]

If the air intake was plugged, then the engine would start pumping out black smoke. Assume Marv would have said so, as he reported on the water out of the exhaust. Start w/ the fuel system.