Engine Knock!!

[gaddington]

Alright, I just installed my marine injectors and had the truck timed last week TDCO of -1.94. After installing my new injectors, at cold start up (30 degrees F), I get a horrible nock for about 1 1/2 minutes then it goes away. What does everyone think. Is it the TDCO setting or a problem. Please help!

What does leaking injectors sound like. Is this a problem or is it OK to drive!! Thanks!!!

[sixnickel]

How long have you let this engine run? Sometimes it takes up to a hour and a half to bleed all the air out. Air in the lines and injectors will make noises come out of that engine that will scare the life out of you and then some!!! If this noise started with the new injectors I would drive it after it settles down and see what happens , you should be all set.

[Chevylover]

How long have you let this engine run? Sometimes it takes up to a hour and a half to bleed all the air out. Air in the lines and injectors will make noises come out of that engine that will scare the life out of you and then some!!! If this noise started with the new injectors I would drive it after it settles down and see what happens , you should be all set.


up to an hour and a half ?????????????????????????

I think if you have done any work at the injectors or fuel lines behind the fuelfilter, it should bleed the air out with about one or two times cranking. Everytime you turn the "ignition" on the liftpump will pump the fuel to the IP and while cranking the injectors open and the air can bleed away.

Am i wrong with my thought ? Changing the fuelfilter will also cause air in the system, but after cranking two times the air is gone.

Cu,
Sven

[sixnickel]

Hey Sven I said SOMETIMES. And thats not to start it. Thats to get it to quite down and not sound likes it's going to blow up!! 99% of the time it will quite down in a few minutes. If I have to bleed a new pump or a set of injectors or both I just bleed the 4 left side injectors. I tighten the right side before the turbo goes on and forget about them. There a pain in the but with the turbo in place. A couple of 15 second cranks you will have fuel at the injectors, tighten the line nuts and it's running, but banging and rapping for what seems for ever till all the air works out. At work I had a old International 7.3NA take over a hour to quite down after a set of injectors and a pump. And it started after a 15 second crank. That was over 100,000 miles a go and it's still going strong (for a 7.3NA) .

[Chevylover]

Hey Sven I said SOMETIMES. And thats not to start it. Thats to get it to quite down and not sound likes it's going to blow up!! 99% of the time it will quite down in a few minutes. If I have to bleed a new pump or a set of injectors or both I just bleed the 4 left side injectors. I tighten the right side before the turbo goes on and forget about them. There a pain in the but with the turbo in place. A couple of 15 second cranks you will have fuel at the injectors, tighten the line nuts and it's running, but banging and rapping for what seems for ever till all the air works out. At work I had a old International 7.3NA take over a hour to quite down after a set of injectors and a pump. And it started after a 15 second crank. That was over 100,000 miles a go and it's still going strong (for a 7.3NA) .


Now i got it and if i have read your post before better, i have read that you wrote "somtimes". I read you post to fast, so i didn't recognize this little word.

I know that is BS to change the injector on the turbo side. I did this on mine WITH the turbo in. Driver side - 4 injectors about 1 hour. Passanger side WITH turbo in about 7 hours for 4 injectors !

Cu,
Sven

[Robert James]

What type of injection pump do you have? Most the time the marine injectors won't function properly unless you have a marine manual injection pump. It's one of those things they never tell you till after you have purchased and installed the new injectors. Beware of the marine injectors, I just toasted a motor because it washed the cylinder walls with too much fuel and burn't it up. I had to get a new Xceptional 6500 from those guys in Alberta.

Good luck.

Robert