Engine knocking LDS-456

[davidb56]

Blowby usually is from the rings not seating/broken in yet on a rebuild. Are you getting some blue smoke out the exhaust? Id be more concerned with the temp. it seems like a stuck thermostat. Also check the radiator for exhaust gases. you can get a kit from the auto parts store or watch for bubbles (not the stripper) in the radiator with the cap off and running. I had to replace my temp sender on my truck as it always showed cold, now it comes up to temp at 180F.

 

[Oerthedge21]

I couldn't really tell, exhaust still smokes pretty good at idle like before, although i think it was more a a grey cloud like it used to be, didn't seem too blue. And I'm only concerned about compression since I think I might've forgotten to check the distance between the ring gaps on some of the pistons when I put them in, so I wanna make sure. Plus it just doesn't feel right, maybe it sbecaise it's been so long since I drive it and it's also all new and un-broken in, but something about the powertrain just doesn't feel right. So I'm gonna just make sure, plus some of the valves had a little pitting on the seats. I lapped them as best I could since new valves and seats and all that work was out of the question in terms of time and price. That extra piece of mind for not terribly too much work of a compression test will go a long way. As for the temp, I gotta empty my buckets first because I wanna flush it out anyway, I'm sure theres more crap hiding in the block somehwere, and probably the radiator too. Plus a whole batch of fresh coolant so that I know what I'm working with would be good.

 

[Oerthedge21]

And what concerns me about the temp is that I never saw it doing this before the rebuild. I used to check the gauge here and there and I can't ever recall seeing t go past 220, even in the few days here where it was in the 90s, felt like I was melting trying to drive that thing.

 

[davidb56]

piston rings rotate up to 1rpm at engine operating speed. Where ever you set them...they moved already. But you had better get that temp under control.

 

[Oerthedge21]

In terms of position I mean the distance between the rings gaps, the way you're supposed to turn them so that the ring ends are a certain distance away from each other so that they don't leak compression. And yes the temp is very high on my concern list, I plan on addressing that as soon as possible

 

[davidb56]

In terms of position I mean the distance between the rings gaps, the way you're supposed to turn them so that the ring ends are a certain distance away from each other so that they don't leak compression. And yes the temp is very high on my concern list, I plan on addressing that as soon as possible

I understand, but they don't always rotate together and at the same rpm when the engine is running, so wherever you placed them, they've already moved around. You can google/research the data on it. The actual fit/gap between the individual ring when its placed into the cylinder is more critical than the staggering of the rings. You'll be fine....

 

[Oerthedge21]

Ah, I was unaware of that. I was taught to always stagger them a certain distance depending on how many rings there are, so that's just what I always followed since I was never told otherwise. I picked up some coolant flush today, as well as a thermometer, gonna try and figure out this cooling issue

 

[davidb56]

Ring gap position is supposed to be staggered when installing them. there are often instructions stating it too. Im just stating that they will rotate around when the engine is running, so if you forget to do it, its not that critical.

 

[davidb56]

http://www.diagnosticengineers.org/journal_ articles/Ring Gaps vs Knowledge Gaps.php

 

[Oerthedge21]

Started it up to warm it up and get the coolant flowing before I drained it. While it was warming up I was once again poking around the engine and listening and feeling for things. I noticed it starting to make a tick. It's a bit more pronounced in the video from in the cab. Seems to be coming from mid/lower end of the engine at the rear. With hand in the heads, oil pan, block side, and even the exhaust manifold before it got too hot I could not feel any shake or vibrations that seemed off. Truck does stumble a bit at idle when cold now, something it didn't do before. I'm assuming this is also a byproduct of the rings still not being sealed to the cylinders. That ticking has me worried though. I don't wanna throw a rod or shear the crank after I just rebuilt it. Should I drop the pan again and check torques on the rods and maybe plstigauge them to see that one isn't wildly loose? I'm not too keen on bottom end issues as I've never had a vehicle or piece of equipment with problems down there, always just heads, valves pistons etc. Oil is still clean and no sparkles.

https://youtu.be/CWfWAlrdkSw
https://youtu.be/gp78HOkXMgc
https://youtu.be/o88Iqv6kyVU

 

[royalflush55]

I would check valve adjustment next.

 

[Oerthedge21]

That was my plan, in the process of pulling he valve cover right now. I adjusted them when I put it together but it's very possible I forgot one or that they settled in and need to be checked. So far my luck has been pretty mediocre so I'm hoping for once it's something easy

 

[Oerthedge21]

Valves are still in spec. Ran engine with valve cover off, felt each rocker, no notable locks or odd feelings. Pushed a piece of wood onto the end of each rocker while running, no difference in sound.

 

[davidb56]

A rod or main knock is real distinctive...its a "knock" almost like on a door. You have a ticking sound like a valve adjustment. But mine sounds like that all the time until the rpm's come up above 1500.

 

[Oerthedge21]

It seems to persist,although I can't tell just because of how much noise there is after 1000 rpm. And I did some temp checking as well. It would appear my gauge or sending unit had died on me since the rebuild, IR thermometer read a high of 160 anywhere i stuck it. Gauge was pegged out at 240. Let it idle like that for a few minutes, continually necking temps and nothing was more than 160. I guess I'll order a new gauge and unit, and save the flush and coolant change for when I have them. Also have 6 gallons of John Deere break in oil on the way, gonna order a spin on kit for the oil filters too and get that on when I swap out this oil for the break in oil. A friend if mines father is a lifelong diesel mechanic who I trust to know what he's talking about, I'm gonna try to have him come take a listen, even if you're right and it just sounds like that a second opinion from someone else would really help me not feel nervous. The only reason in worried is because it seems to be coming from just the rear of the engine, it doesn't sound like it's up front too.

 

[royalflush55]

Any chance there is an exhaust leak?

 

[Oerthedge21]

I'm not sure, I thought about it some afterwards. If I reach down and pull the throttle right at the back of the IP, so my face is right there in the engine, when I rev it I can hear kind of a whooshing I guess it could be called near the rear that I don't seem to hear up front. I tried feeling around the exhaust manifold but since I had just driven it it was pretty hot and with an already hurt shoulder today I don't wanna throw in a burnt hand along with it. I'm gonna screw around with it some more tommorow and crank down all those manifold bolts again if I get time

 

[Oerthedge21]

Toyed with it some more today. Cranked the exhaust manifold down some more, some nuts weren't super tight but it was not the issue. Also found out that the reason the truck came with another heater core is because the one in it is bad, nice puddle under there this morning. I tried cracking injector lines just for the **** of it which didn't do much, tick seems to maybe get a little quieter if i crack line #6, but it's hard to tell with how it starts to skip being down an injector

 

[Oerthedge21]

Let it run some more, and my friend's father stopped by as well. We poked around some more and listened to it at different rpms and such. We noticed through listening to it for quite a while that the ticking, if you really focus and tune it all the other noises, is actually somewhat inconsistent, and sounds kinda like there's a marble rattling around in the rear of the engine. I'm gonna pick up a mechanics stethoscope tomorrow after work and take a more in depth listen. I'm also gonna see if I can get the chance to listen to one that a friend of a friend has to see how it sounds.

 

[davidb56]

Can you swap #6 injector with #1 and see if the noise moves to the front?