2F engine noise diagnosis (1 Viewer)

[Rooster47]

My 2F has developed what at first seemed like a ticking noise, and now seems more like a slight knocking noise. I'm not sure how to proceed with diagnosing it.

A couple of weeks ago, I thought I would adjust the valves to see if it went away. I adjusted the valves with the engine running, and it didn't improve the noise.
I also thought the noise might be an exhaust leak between the header and the head. I tried tightening all of the bolts, but found no loose ones. I'm ready to get rid of the header, as I've dealt with exhaust leaks there in the past.

Yesterday I did a compression test after warming up the engine. The numbers looked decent, 145-140-150-145-145-150.

At this point I think there's a slight chance it could be an exhaust leak, but the sound doesn't seem right for that. I'm afraid it's a bearing in the lower end.
I'd appreciate any advice on next steps.

I attempted to add a video of the noise here, you can perhaps here it most pronounced when the engine is revved a bit towards the end of the clip.


Pictures of spark plugs:

 

[charliemeyer007]

What do you have for oil pressure on a direct read gauge? I run a double man-a-fre header gasket that was installed wet. I made custom stepped washers, longer "studs" to account for the double gasket and much thicker stepped washers. Stainless steel nuts with high temp anti seize compound. Torqued by 1/3 in sequence, the again at 100% after it has been run up to hot. After a few cycles adain at 100%. I never have leaks. Gaskets and header have been on at least 2 engines.

 

[Grayscale]

I've never been there, but, I thought that you narrow-down the noise with a stethoscope.

Guide to Diagnosing Common Engine Noises

Got a knock sound from your engine...or maybe a tapping noise in your engine? Learn how to diagnose common engine sounds so you can troubleshoot the underlying problems.

www.onallcylinders.com

 

[pb4ugo]

You can use a piece of heater hose and hold it to your ear, then run the other end along the head where the intake and exhaust meet and listen for a leak. Do it from underneath too. You can use a long screwdriver or something similar as a stethoscope. I try to stay on the block or head and off the tins.

 

[zerotreedelta]

Narrowing down with tubing/stethoscope would help (or even moving the phone while taking video, works surprisingly well).

If it's up front, it could just be a little bit of cam gear knock...it sounds a bit like bottom end noise.

 

[pb4ugo]

You can also pull 1 spark plug wire at a time. If the knock goes away, then that cylinder might be suspect.

 

[OlYellr]

You can also pull 1 spark plug wire at a time. If the knock goes away, then that cylinder might be suspect.

I did that when I had strange sound. I suggest 1) rev up too and see if you get a "whomp" sound.

One plug made sound go away like @pb4ugo mentioned - ended up being a main bearing about to spin, which brings me to #2) don't drive around a lot until you can isolate/rule out a spun bearing (or about to spin). (this fix is way cheaper).

Here is my video - and you can year an extra sound when the putting some gas to it.

 

[Rooster47]

@pb4ugo I hadn't thought of pulling the wires off individually. I gave it a try and was actually pretty surprised at how little of a difference it made with most of the cylinders at idle. I could barely tell a difference. There were 2 that seemed to make the general engine noise louder when I pulled them off. But nothing that really helped me isolate the concerning noise further.

Then I tried the stethoscope approach with a long screwdriver. Worked really well when I could get it right against my ear. I could definitely hear the noise, but isolating it was difficult. I think I'm maybe 75% confident that it is in the bottom end, I just wasn't able to get a good feel for exactly where, maybe towards the back cylinders.

@OlYellr That sounds a lot like what I hearing. I'm getting more certain it's time to pull the pan.

Thanks for the help all.

I guess I pull the oil pan now. I'm not sure how to identify the issue after that though, do I just need to pull each rod cap and look for signs of wear/damage?

 

[Mark Jennings]

My 2F has developed what at first seemed like a ticking noise, and now seems more like a slight knocking noise. I'm not sure how to proceed with diagnosing it.

A couple of weeks ago, I thought I would adjust the valves to see if it went away. I adjusted the valves with the engine running, and it didn't improve the noise.
I also thought the noise might be an exhaust leak between the header and the head. I tried tightening all of the bolts, but found no loose ones. I'm ready to get rid of the header, as I've dealt with exhaust leaks there in the past.

Yesterday I did a compression test after warming up the engine. The numbers looked decent, 145-140-150-145-145-150.

At this point I think there's a slight chance it could be an exhaust leak, but the sound doesn't seem right for that. I'm afraid it's a bearing in the lower end.
I'd appreciate any advice on next steps.

I attempted to add a video of the noise here, you can perhaps here it most pronounced when the engine is revved a bit towards the end of the clip.


Pictures of spark plugs:
View attachment 3753850View attachment 3753851View attachment 3753852View attachment 3753853View attachment 3753854View attachment 3753855

I think you are just hearing valve train noise. Generally, you’ll hear rod bearing noise under load when you back off the throttle. It’ll be a defiant knock. Pull the valve cover again and start the engine, look at rockers and make sure oil is coming out of each rocker vent holes. Adjust the valves again, engine hot but off. I’ve never had any luck adjusting with the engine running.

If you’re really concerned , drain the oil and cut open, inspect the oil filter (if it’s a spin on). I also routinely stick my finger in the oil drain hole a see if there are any chips….the chips/sludge would be non-magnetic if there were a bearing issue.

 

[OlYellr]

@pb4ugo I hadn't thought of pulling the wires off individually. I gave it a try and was actually pretty surprised at how little of a difference it made with most of the cylinders at idle. I could barely tell a difference. There were 2 that seemed to make the general engine noise louder when I pulled them off. But nothing that really helped me isolate the concerning noise further.

Then I tried the stethoscope approach with a long screwdriver. Worked really well when I could get it right against my ear. I could definitely hear the noise, but isolating it was difficult. I think I'm maybe 75% confident that it is in the bottom end, I just wasn't able to get a good feel for exactly where, maybe towards the back cylinders.

@OlYellr That sounds a lot like what I hearing. I'm getting more certain it's time to pull the pan.

Thanks for the help all.

I guess I pull the oil pan now. I'm not sure how to identify the issue after that though, do I just need to pull each rod cap and look for signs of wear/damage?

When I pulled the pan, I had schizzel in the bottom of the pan - you can take the bearing caps off and see the bearings - you will know. I can find pictures.. well wait... this should take you to a video on my thread


Builds - My first '40 and the venture - https://forum.ih8mud.com/threads/my-first-40-and-the-venture.1307023/post-15172275

 

[pb4ugo]

I'd do a wet and dry compression test, b4 tearing into it.

 

[Pighead]

Here is my video - and you can year an extra sound when the putting some gas to it.

Yes, you can really hear the difference. I think OPs noise is valve train with a little exhaust leak