Help! Noise in my engine

Bellcrank

Member
Joined
May 8, 2019
Threads
0
Messages
47
Well, in practice this happens, but when recording with increased RPM, the noise of the discharge increases (mufler), suppresses the TUC TUC TUC ... and it is not very clear.
In the video I forced a low RPM in order to make the TUC TUC TUC clearer ... did you notice?
Thanks , I did hear.Go to the source with a long dowel or ready rod etc. between the engine case and your ear to check noise/engine rpm relationship.
 

Bange

Well-Known Member
Joined
Mar 28, 2021
Threads
14
Messages
253
It is my friend, impossible to notice any difference ... by this procedure I would not condemn the gap between the crankshaft and the connecting rod foot (crankpin journal).
But the slack can come from the two other points (mag journal or PTO journal).
 

Bange

Well-Known Member
Joined
Mar 28, 2021
Threads
14
Messages
253
Thanks , I did hear.Go to the source with a long dowel or ready rod etc. between the engine case and your ear to check noise/engine rpm relationship.
Let me see if I understand ... do you mean by a big screwdriver with the cable in the ear and the crack in the motor housing (like a stethoscope)? We do this procedure here to detect bearing snoring on car wheels, bearing alternators, air conditioning compressor ... is that it?
1617230343941.png
 
Last edited:

slomo

Lawn Pro
Joined
Jul 14, 2019
Threads
78
Messages
5,065
You can use a piece of rebar, long socket extension, piece of copper pipe and so on.

slomo
 

Bange

Well-Known Member
Joined
Mar 28, 2021
Threads
14
Messages
253
That's what I imagined ... here we always use a long screwdriver ... I'll do it tomorrow morning and post my impressions, but because I don't know a perfect machine, I don't know if it will help.
 

Bellcrank

Member
Joined
May 8, 2019
Threads
0
Messages
47
Here is an idea. Check oil before using mower and use these.
 

Attachments

  • Screenshot_2021-04-01 Mack's Ear Seals Dual Purpose Earplugs.png
    Screenshot_2021-04-01 Mack's Ear Seals Dual Purpose Earplugs.png
    263.7 KB · Views: 3

Bange

Well-Known Member
Joined
Mar 28, 2021
Threads
14
Messages
253
Well, I did the test of auscultating the engine ... not conclusive in the sense of defining the clearance point, regardless of where I place the screwdriver.
One thing that I clearly noticed is that the "tuc tuc tuc" does not increase in intensity with the increase in RPM, on the contrary, it even decreases.
I measured the idle RPM and it is + -1700 (is this normal?) The options are running out and before I open my engine, I still have to hear another one in good condition for a comparison.
 

Bellcrank

Member
Joined
May 8, 2019
Threads
0
Messages
47
Well, I did the test of auscultating the engine ... not conclusive in the sense of defining the clearance point, regardless of where I place the screwdriver.
One thing that I clearly noticed is that the "tuc tuc tuc" does not increase in intensity with the increase in RPM, on the contrary, it even decreases.
I measured the idle RPM and it is + -1700 (is this normal?) The options are running out and before I open my engine, I still have to hear another one in good condition for a comparison.
 

slomo

Lawn Pro
Joined
Jul 14, 2019
Threads
78
Messages
5,065
Well, I did the test of auscultating the engine ... not conclusive in the sense of defining the clearance point, regardless of where I place the screwdriver.
One thing that I clearly noticed is that the "tuc tuc tuc" does not increase in intensity with the increase in RPM, on the contrary, it even decreases.
I measured the idle RPM and it is + -1700 (is this normal?) The options are running out and before I open my engine, I still have to hear another one in good condition for a comparison.
I've read around 1850rpm is low idle speed.

Not good to idle these air cooled engines like a Harley Davidson at 400rpm. You want a full 3200 to 3600 revs for normal ops. Somthing about lack of lube at low revs. Check your manual for proper rev settings.

slomo
 
Top