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Discussion Starter · #1 · (Edited)

This sound is there no matter the engine temp. I live in southern California so ambient temps are mostly high.

It is mostly 3 ticks in a row as heard in the video but it varies.

I have checked the valve lash multiple times and everything has been very close to perfect. I haven't used diesel kleen in probably 4-5 months (i don't think i remember this sound being there when I was using it) so I will try some additives and see if it goes away. I am also going to re-torque the injector lines and the injectors themselves as I have not tried that either.

Doing some research on here and believe that it could be a valve seat, cp3 gear or injectors. There is no smoke on startup nor any excessive blow by. The sound does fade with throttle (i can't hear it around 1500 rpms). It can be heard in the cab with windows up or down. I can narrow it down to the drivers side of the motor but thats about it.

I hope this to cost me much, I have a 2600 mile trip at the end of April and need to get all these little issues worked out. The truck has just under 230k on it also.
 

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I would make sure all your injector line hold down clamps are tight...

Just go over the engine bay and make sure nothing is loose..
 

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when you set the lash was there any out more than the others? it really sounds like a lifted valve seat to me, there is a slim chance its injector rattle but you would have lost power and mileage, however i would dump 2qts of tw3 2stroke oil in your fuel tank and top it off go for a 20-25ml dive and see if it quiets it down if it does its in the fuel system i doubt it but go try it and get back to me
 

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Discussion Starter · #4 ·
when you set the lash was there any out more than the others? it really sounds like a lifted valve seat to me, there is a slim chance its injector rattle but you would have lost power and mileage, however i would dump 2qts of tw3 2stroke oil in your fuel tank and top it off go for a 20-25ml dive and see if it quiets it down if it does its in the fuel system i doubt it but go try it and get back to me
I have lost mileage but not power. My MPG is around 15-15.5 right now, it was around 17. I'll try some 2 stroke oil. As for the valve lash, I haven't checked it in about 2 months and that is one other thing that I will be checking again. I don't like the sound of a lifted valve seat, but it that's the problem, at least I would know what it is.
 

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Discussion Starter · #5 ·
After check the valve lash again, there is nothing unusual. Here are a few pics of what the valves look like. This is when cylinder #1 is TDC.



Then after rotating once...



I have looked at a few others' pictures of their valves (valve lash guides) and mine look like theirs (to me anyways). What would a valve seat lifting look like? I imagine the rocker would be sitting higher and if the seat was dropping it would sit lower. Bit if my valve lash hasn't changed nor has it ever been out of adjustment. wouldn't this indicate its not a valve seat?
 

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you will need to check every valve, spec is 10 and 20 so if you find any (most likely 1) out more than the others like say 1 is at 30 and the others are 20-23or24 ish thats your lifted seat!, however if you adj them since you heard the noise they may all be the same....now you can reset the lash roll all of them to TDC and crank the jam nut down till valve hits piston and see if one or more hits before the others, however you will need to have a feel for this, doing it this way is not the best way and not a exact measure but its roughly 20thousands per turn of the nut......i would run the 2 stroke oil first to rule out fuel probs before you get into this to far......here to help Matt
 

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Discussion Starter · #7 ·
okay, i understand what your saying with the valves (will look into this after some fuel additives). I guess the only real way to check the valves is to pull the head off and look. I wish i was back home (where im headed) or else i would be all for pulling the head off. i'll get back after running the two stroke oil. I felt around the motor and can't quite feel anything that corresponds to the sound, but i really don't think that means anything.
 

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good luck man i wish i could be there to help ya, if it is a lifting seat stop driving it now! you can have new&deeper better seats put in, all new valves and springs, and have it ported and polished for $1475 (here), but if that seat drops! 98% of the time it takes the whole with it and then..... well $5k min if you do all the r&r labor....good luck
 

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Discussion Starter · #9 ·
im thinking of how i can possibly do this work if it needs to be done because I live in an apartment. No place to do anything around here except on the side of the road and i'm not sure that is a possibility. another reason why i hate apartments.
 

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Discussion Starter · #10 ·
Update:

I put some diesel kleen in the tank and went for a ride. got the engine warmed up and the noise is quieter now (about half as loud). Its only really audible in park. I used to be able to hear it while sitting at a stop ,light but i haven't. I'll see how this plays out over the next few days. Anyone else ever heard this sound? Also it goes away at 1k rpm, so only a little throttle needed.
 

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Man mine makes the exact same noise and it has bugged me since day one I bought the truck used with it I have tried filling the fuel filter housing with seafoam then turningbit over a few times to get it In the injectors and to me it sounds a little different for a while after but maybe I'll try the 2 stroke oil too

What is the best 2 stroke oil to use I herd some walmart brand one was the best
 

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Discussion Starter · #12 ·
I haven't used any 2 stroke oil in mine. I have only used Diesel Kleen. 2 stroke oil is 2 stroke oil, i'm sure everyone has their preference, but I have never noticed a difference. After running straight diesel fuel for a few months, the video is what mine sounded like. I put some diesel kleen in the filter housing and some more in the tank and it immediately quieted down, so this sound is in the fuel system somewhere. I wen to walmart to get some 2 stroke oil, but they seem to only carry one brand around here. Just pick up a few quarts and dump it in the tank (along with some in the filter housing). The noise bugs me too. I always thought that my engine was about to go, but i feel alot better about it now after trying a few things.
 

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Almost sounds like it corresponds with belt speed rather than engine speed although it still seems even less frequent than belt revolutions. Each cylinder fires aprox 7X per second at idle so if it was a valve or something related it would be at a higher frequency.
 

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Discussion Starter · #14 ·
yeah i was trying to compare it with the injectors firing. if i increased the throttle the ticks came faster so it definitely directly related to engine speed.

i actually had my multimeter connected to the crank position sensor output (rewired ignition system) and it was reading ~28 hz. so that equates to about 840 RPM. This was at idle btw, which was a little high even though the cluster was reading ~750. There were 3 ticks in a row which made me assume that was an injector firing all three of its events. So my assumption is that I have a bad injector, still haven't had the injectors tested though, will soon though.
 

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I actually meant engine rotation frequency (850-900rpm) The belt will also move faster with increased engine speed.
Injector frequency will be around 7 injections per second at idle and the noise is a lot slower than that.
 

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check your pulleys for wobble, and check your cp3 for tightness
 

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I think the noise is a combustion noise, caused by the ecm fooling with the timing to hold a steady idle speed.
 

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Discussion Starter · #18 ·
The belt tensioner does have some movement to it while the engine is running, how much is normal? I don't notice any other pulleys wobbling or moving.

TedT,
If the ECM is adjusting its timing, does this mean there is something out of the ordinary?
 

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Man u need to adjust your cp3 or what ever it is the high pressure pump I did mine today and the truck is much quiter
 
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