Farm Equipment - Engine vibration

Print Page | Close Window

Engine vibration

Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=208025
Printed Date: 08 Sep 2025 at 6:20am
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: Engine vibration

Posted By: Dennis(IA)
Subject: Engine vibration
Date Posted: 01 Sep 2025 at 9:17pm

I have had this tractor over 20 years and this year it seems to have excessive engine vibration, sometimes, when the throttle is halfway or more. I noticed it a couple of weeks ago. After that it seemed normal, then today ( bush hogging a small field) it seemed excessive. This is without running the pto or anything. I don’t know, maybe I am going crazy.

Replies:

Posted By: DrAllis
Date Posted: 01 Sep 2025 at 9:40pm

What model and gas or diesel ??

Posted By: Dennis(IA)
Date Posted: 02 Sep 2025 at 8:33am

Gas. I know 4 cylinders vibrate anyway, but this seems excessive, I should remove the plate under the flywheel and clutch and have a look.

Posted By: Dennis(IA)
Date Posted: 02 Sep 2025 at 8:35am

WD 45.

Posted By: DrAllis
Date Posted: 02 Sep 2025 at 8:56am

Tighten up the bolts that hold the engine to the bellhousing (4). Tighten up the bolts that hold the engine across the frame at the front (4).

Posted By: only AC orange
Date Posted: 03 Sep 2025 at 7:58am

Crankshaft pulley bolt worked loose?

Posted By: Dennis(IA)
Date Posted: 03 Sep 2025 at 8:09am

Good suggestions, I will check those bolts. Simple things that need to be checked, thanks.

Posted By: DrAllis
Date Posted: 03 Sep 2025 at 8:11am

Crankshaft pulley being loose usually causes a knocking sound.

Posted By: SteveM C/IL
Date Posted: 03 Sep 2025 at 11:53am

Yeah, the knocking sound is what told me I had a problem. Had to be at the front end at idle to catch it. Wore the crank nose...turned into a $2000 rebuilt engine.

Posted By: Dennis(IA)
Date Posted: 04 Sep 2025 at 8:19am

All bolts are tight. I put my big Channel lock pliers on the front pulley, and I thought I had some play ( the engine has a clunk) also. The second time I tried it I did not see or feel any play. Time to take the pulley off ( front seal is leaking ) and check things out.

Thanks for all the suggestions.

Another note is that I am hard of hearing, I wear hearing aids, but not the same as being able to hear.

Posted By: Steve A
Date Posted: 04 Sep 2025 at 5:36pm

I'm that way with the hearing aids too. Too much amplification with them in, wary of losing them. By the time an unusual noise is loud enough for me to hear its usually at the point of "Aw Sh_ _ " or buying parts.