86 454 noise? - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Engine
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 09-19-2010, 02:17 PM
Registered User
 
Join Date: Aug 2010
Location: New Jersey
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
86 454 noise?

I have a 86 454 in my RV(new to me-had no noise) with 21k miles and a tapping/knock noise. It all started at the end of my first long trip, a 600 mile trip. We pulled off of the highway, almost home and there it was, a tap/knock noise at idle. Good oil pressure, changed oil and filter, added Marvel Mystery, still noise. Adjusted valves, still noise. Everything pointed to a bad lifter. Replaced all lifters, still noise. I had changed the mech fuel pump before the trip (just in case) so I thought maybe it was bad. The rv has 2 pumps, one electric back by the tank and the mech on the engine. I removed the pump shaft for the mech pump and still the noise. Checking this website, the last hope was loose flywheel bolts. All tight but.....I tried to run the engine when the converter was unbolted and the noise is gone!!! Problems in the tranny but what? It seems to be a th400 or th475, 13 bolts on pan. Any ideas? Joe

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 09-19-2010, 02:48 PM
eloc431962's Avatar
Evil Wicked Mean And Nasty
 
Last wiki edit: Pilot bearing and bushings
Last journal entry: roof repair
Last photo:
Join Date: Nov 2008
Location: back in the garage.
Posts: 13,762
Wiki Edits: 37

Thanks: 50
Thanked 28 Times in 24 Posts
You need to check the flywheel for cracks, I have seen a cracked flywheel do this. JMO


Cole
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 09-19-2010, 05:40 PM
Registered User
 
Join Date: Aug 2010
Location: New Jersey
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
hard to believe?

Cole,

I'll check it again tomorrow but let's say it's a cracked flywheel, how is the noise being made? I would think for a cracked plate to make that kind of noise I'd have seen a distortion of the flywheel. I'll post soon.
Thanks, Joe
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 09-19-2010, 05:45 PM
lookatme's Avatar
Member
 
Last photo:
Join Date: Jan 2003
Location: bandera texas
Posts: 141
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
the flywheel cracks around the center bolts, and what you hear is the flywheel beating against itself as it flexes. you wont see much if any distortion. and you have to look really hard for the cracks.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 09-19-2010, 07:38 PM
eloc431962's Avatar
Evil Wicked Mean And Nasty
 
Last wiki edit: Pilot bearing and bushings
Last journal entry: roof repair
Last photo:
Join Date: Nov 2008
Location: back in the garage.
Posts: 13,762
Wiki Edits: 37

Thanks: 50
Thanked 28 Times in 24 Posts
Quote:
Originally Posted by lookatme
the flywheel cracks around the center bolts, and what you hear is the flywheel beating against itself as it flexes. you wont see much if any distortion. and you have to look really hard for the cracks.

X2 What he said.


Cole
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 09-22-2010, 07:15 PM
Registered User
 
Join Date: Aug 2010
Location: New Jersey
Posts: 7
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
What do you guys think about this?

Ok, I inspected the flex plate and couldn't find any cracks anywhere. I did find that the flex plate and the whole crankshaft can move forward and back about 1/4". I can do this by prying the flex plate away from the rear of the engine and then grabbing it and pushing it forward. That doesn't seem right at all. The manual says the thrust bearing clearance should be .003" so 1/4" is way too sloppy. I didn't find anything on this website but another site suggested "converter balloning". They suggested a build up in trans pressure from a clogged/restricted cooler line could cause this. I guess if the converter can expand and push on the rear of the crank, I guess the weak area is the crank's thrust bearing. I'm guessing the motor is shot. Unbolting the converter and running the engine allows the crank to find a place where what ever is hitting internally, to not hit. Does this sound right?
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 09-22-2010, 09:07 PM
lookatme's Avatar
Member
 
Last photo:
Join Date: Jan 2003
Location: bandera texas
Posts: 141
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
you need to check the areas of the flywheel just outside of the crankshaft bolt circle. look for tell tale rust. take a knife and run it from the center of the flywheel to the outer edge. also around the crank bolts. if it catches. you found a crack. they are hard to spot. the crankshaft moving back and forth could of caused the flywheel to break. if it is the thrust bearing, all youre out is a set of bearings and a crank.
Reply With Quote Quick reply to this message

Recent Engine posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Gen6 Vortec 454 Need help before its gone!! 973kgt Engine 3 03-31-2010 05:53 AM
need help with my 454 build black_chevy Engine 9 12-09-2009 04:22 PM
Turbo 400 ex 86 - 88 Duallie 454 opelitis5 Transmission - Rearend 7 07-10-2009 07:07 AM
40 Merc steering noise (weird) Da Hellion Suspension - Brakes - Steering 6 01-02-2006 09:41 AM
Squeezing a little more power out of my 454 RObs71Nova Engine 8 05-21-2005 03:38 PM


All times are GMT -6. The time now is 03:00 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.