Home | Classifieds | History | Technical | Links | Store | About Us | Email
Topics Topics Edit Profile Profile Help/Instructions Help Member List Register  
Search Last 1|3|7 Days Search Search Tree View Tree View  

Definitely a Knock (Graymarine 109)...

Old Marine Engine » Gray Marine Gas Engines - 4, 6, and 8 cylinder » Definitely a Knock (Graymarine 109) « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Eric Peggs
Advanced Member
Username: epeggs

Post Number: 41
Registered: 02-2017
Posted on Tuesday, October 16, 2018 - 09:04 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only)

Fellas,
We have a knock....
here is a link to the video....hopefully this one will work better than before: Try copying and pasting if a clickable link doesnt show up.

https://photos.app.goo.gl/Efh4XyXqbzKp6Py28

My dad took the head off and found this on the #1 cylinder.
https://photos.app.goo.gl/MYxmi7F68YjEucD57

We always felt like we had a knock, but thought it was just ignition knock. So we adjusted the timing at 3/4 throttle and got most of that, if not all of that out. Then I moved onto the carb to try and tune it in at 3/4 speed. Thats when the knocking started REALLY REALLY BAD like in the video.

So we pulled the engine and are looking into to having it machined and re-sleeved. Has anyone ever had to do this to a 109 or similar engine? Just curious what to look for. If we bore it out, do we need to bore out all cylinders or just the one? Any advice is appreciated.
https://photos.app.goo.gl/Efh4XyXqbzKp6Py28https://photos.app.goo.gl/MYxmi7F68YjEucD57
Top of pagePrevious messageNext messageBottom of page Link to this message

J.B. Castagnos
Senior Member
Username: jb_castagnos

Post Number: 1394
Registered: 07-2002


Posted on Tuesday, October 16, 2018 - 07:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only)

You won't know about the cylinders until it is disassembled and measured. I would suspect rod bearing problems, probably Babbitt bearings, crank would have to be ground and bearings re poured.
Top of pagePrevious messageNext messageBottom of page Link to this message

Ned Lloyd
Senior Member
Username: ned_l

Post Number: 180
Registered: 08-2012
Posted on Sunday, October 21, 2018 - 11:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only)

I donít see why just that one cylinder couldnít be sleeved. Maybe you will be lucky and it is just that one wrist pin that is bad and making all that noise. It sure did a job on that cylinder.
(I have a Stover. CT2 stationary engine with similar damage, but on that engine there is just a set screw that holds the wrist pin in place and keeps it from scoring the cylinder (or not if that set screw comes loose.)

Add Your Message Here
Post:
Bold text Italics Underline Create a hyperlink Insert a clipart image

Username: Posting Information:
This is a public posting area. Enter your username and password if you have an account. Otherwise, enter your full name as your username and leave the password blank. Your e-mail address is optional.
Password:
E-mail:
Options: Automatically activate URLs in message
Action:

Administration Administration Log Out Log Out   Previous Page Previous Page Next Page Next Page

Home | Classifieds | History | Technical | Links | Store | About Us | Email
&copy 2005 OldMarineEngine.com, P.O. Box 188, Forest Dale, VT 05745-0188 • Phone: 802-247-4864 • All rights reserved.
   Marine Engine Seloc Repair Manual Lookup Tool

marine gas engine repair and restoration