Ive got a noise, I think its a lifter. I want to try additive but dont know which one. I realize this is poor practice but I dont want to just throw parts at it. If anybody has any recommendations on what kind (preferably from major outlets) or any experience with marvel mystery oil. Ive checked with all the mechanics I know, at least four of em, and they dont hear this noise. there is a noise and I want it resolved. The mechanics and friends say just run it but when something is wrong I want it fixed! I figured an additive may point me in the right direction. Ive gone over it with a stethoscope and its coming from the rear of the engine. Seems like a spun main bearing to me but its not making enough noise to be that IMO. Im not looking for diagnosis just additive recommendations BUT I have changed the cracked flex plate and the noise is still there. So if you know of anything back there that would make a high pitched clanking noise im all ears!!!!!!!!!!!! Like the flex plate smacking the flex plate but its not. . . . Ill be, changing the oil tomorrow so quick advice is greatly appreciated.

 

High pitched clacking noise in the rear?

Sounds like air trapped in the fuel being fed through the injectors.

The most common and likely cause of this is the fuel pickup in the tank and the fuel line connections at the fuel pump inlet. Do a search of FTE for the "hutch" mod or "Hutch, Harpoon" for the cure. The Harpoon mod is another modification you can perform if you drop tank that is almost free (costs about 10 minutes).

As for an oil additive .....Archoil or Hotshot secret is the only think I would recommend and it is not available over the counter that I have seen. You can add it at any time no need to wait for an oil change and you use a very small amount so it won't throw off the fill levels.

Marvel mystery oil? Bad idea on a HEUI injection system that pressurized oil to 2500psi+ as are most oil additives for this engine. Hotshot secret and Archoil are the only additives that I know of that were designed with this type of injection system in mind.

 

I guess my signature isnt working. Ive done the HUTCH and harpoon mod and replaced the passenger side fuel line and rebuilt the fuel bowl with parts from diesel O rings. Its coming from the rear of the motor and you can hear it better under the truck. . . Its driving me crazy. Thank you very much for the input. Ill order those additives. Any other ideas are appreciated.

 

Possible that #8 injector. Have you done an buzz test with AE?

 

Sorry, I'm on my phone and signatures don't show up.

When you did the hutch mode did you eleminate the quick disconnect fittings on the fuel pump suction side?

A quick check for air in fuel is to attach a hose to the fuel bowl drain tube and with the engine running open the valve and catch the fuel in a clear container so you can look for bubbles.

Also, torque converters have been known to rattle, they usually sound more like a coffee can full of marbles though.

 

its definately a tap tap tap and changes with RPM. I cant hear it as much when im coasting which indicated an injector but it sure is loud. Im new to diesels so. . . I was suspecting the torque converter as well. I had a buzz test done but the 'mechanic' seemed to think it was all good. Im going to have hime do it again and pay more attention. I didnt know anything at the time. Theres no air in the fuel, I eliminated to "quick connect" but impossible to take apart fittings. I still suspect a lifter or sticking valve. When im done with the oil change ill see about a miss in the exhaust. Evidently holding a paper to the exhaust pipe and seeing if it sucks back will indicate a sticking valve.

 

so the knock is much quiter and less frequent with fresh 5w-40 full synthetic. That tells me. . . . .?

 

1) What oil brand/viscosity did you change from?
2) How many miles were on the oil you removed?
3) What brand oil did you put back in the engine?

Perhaps your HPOP or LPOP (or both) is/are getting tired, and the better flowability of the fresh synthetic is getting to where it needs to go a little more easily.

Could also be a difference in the fresh oil's film strength or Extreme Pressure (EP) additives, or both.

- A better film strength will decrease the likelihood of contacting surfaces to actually push through the thin film layer to make an actual metal-to-metal surface noise.

- A higher presence of EP additives can decrease friction and consequently reduce metal-to-metal contact noise (much lesser impact on noise reduction as compared to the film strength issue).

 

I think a decrease in friction, causes a decrease in noise?

 

Increase in friction resistance = decrease in friction. The first is probably a bad choice of words because the latter is more clear. My apologies for confusion. I'll fix it in my post.

Yes, there can be some noise reduction associated with it, albeit a small reduction. A higher oil film strength would make a greater difference.

 

I have no idea what was in it or how long it was there. It was sure black but I hear thats common with diesels. I put Mobil 1 full synthetic for turbo diesels. I can still hear the 'knock' but its infrequent now. I still think its a bad lifter or sticking valve. Anybody have a link to what a noisy injector sounds like? I went around with a stethoscope and can her it best on the oil pan. Not sure if I said that already.

 

Has you injectors ever been replaced? How is your cold morning starts? I would start with some power kleen diesel and see if she starts to quiet down, but at 250,000, I am leaning towards injector noise..

 

Marvel oil may not fix it, but also will not hurt it.
I ran 4 gallons in 1 tank once, to (fool myself into thinking I was) cleaning the fuel system.

 

But if he puts it in the oil system it may cause foaming, not saying it will cause i don't know but wouldn't risk it in my truck.

 

I usually hear 4 different noises in my truck. It just depends on what day of the week it is. I added some Hotshots to my last Delo 400LE change and some of those noises are gone and the rest are quieter. The trade off is, now I have some occasional weird ICP issues. At light or no throttle, the ICP swings 3-400psi with no change in IPR DC, throttle position, or Inj PW.