4.3 sx drive loss of power and knocking sound

[aristo_craft_19]

I just fixed my overheating problem on my boat and had thought that the loss of power was due to the overheating issue but guess not. Took it out today and when i have it wot there is no power and a knocking noise. I didnt go far before i put the boat in neutral and it died. after about 10 minutes i was able to start it again and slowly get it back to the ramp to take it out but it died quickly again. Any suggestions on where to start?

 

[aristo_craft_19]

Re: 4.3 sx drive loss of power and knocking sound

ok so i started the motor this morning and this is what i am hearing. I accellerated to 2000 rpm and it would hold there for about 10 seconds and then loose acceleration. i am also hearing a chirping noise from the pulley.

 

[Bondo]

Re: 4.3 sx drive loss of power and knocking sound

Ayuh,... Welcome Aboard,... Check the fuel filter for water, crud, 'n bad gas,...

 

[aristo_craft_19]

Re: 4.3 sx drive loss of power and knocking sound

i will check the fuel filter and let you know what i find out. i took a video just now of my engine so you can hear it. Not sure if this is helpfule but below is a link to youtube.

Boat engine.mp4 - YouTube

 

[Bondo]

Re: 4.3 sx drive loss of power and knocking sound

i will check the fuel filter and let you know what i find out. i took a video just now of my engine so you can hear it. Not sure if this is helpfule but below is a link to youtube.

Boat engine.mp4 - YouTube

Ayuh,... Sounds like a rod knockin',.... Do a compression test on it,...

 

[aristo_craft_19]

Re: 4.3 sx drive loss of power and knocking sound

do you have anything that can show me how to perform a compression test?

 

[Bondo]

Re: 4.3 sx drive loss of power and knocking sound

do you have anything that can show me how to perform a compression test?

Ayuh,... Have a look in the Adults Only section, at the top of this forum,......

 

[Don S]

Re: 4.3 sx drive loss of power and knocking sound

This should explain how to do a proper compression test.

View attachment 97-25 Compression Test.pdf

 

[aristo_craft_19]

Re: 4.3 sx drive loss of power and knocking sound

ok did the compression test and came out 175, 150, 155, 150, 150, 160

 

[aristo_craft_19]

Re: 4.3 sx drive loss of power and knocking sound

with compression being good what would be my next action?

 

[Don S]

Re: 4.3 sx drive loss of power and knocking sound

When you did the compression test, with all the plugs out did it still knock? was it any louder on one of the cylinders when you tested it?

Quite honestly, with that noise, I would pull the engine and the pan and find out what it is.

 

[aristo_craft_19]

Re: 4.3 sx drive loss of power and knocking sound

did not seem to be any different on any of the plugs. I went ahead and did a tune up and put new plugs, wires, dis cap and rotar in and was going to start to clean all the connections and dropped a screw and noticed that there is oil and and found a 9/16 bolt down there that i dont know what its to. so you think i should pull engine out? I guess i was hoping this would be something simple and i am not going to end up with 6,000 dollar paper weight in my front yard.

 

[Don S]

Re: 4.3 sx drive loss of power and knocking sound

Post a picture of the bolt you found, and how much oil was in the bilge?

 

[aristo_craft_19]

Re: 4.3 sx drive loss of power and knocking sound

 

[aristo_craft_19]

Re: 4.3 sx drive loss of power and knocking sound

 

[Don S]

Re: 4.3 sx drive loss of power and knocking sound

Sorry, doesn't really help. Guess you'll find out once you get the engine out and the pan off.