84-85 Trucks & 4Runners 2nd gen pickups and 1st gen 4Runners with solid front axles

Cam Lobe Ground Down

Thread Tools
 
Search this Thread
 
Old 08-11-2018, 02:09 PM
  #1  
Registered User
Thread Starter
 
shisha1999's Avatar
 
Join Date: Jun 2015
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
Cam Lobe Ground Down

My cam lobes are done and need to rebuild engine head. What makes more sense to rebuild head or purchase new? What are the pros and cons including cost? There is a machine shop near me that is highly rated but I dont know the experience with 22REs. Also, what would cause this? Low oil pressure? Thanks for the advice.



Old 08-12-2018, 06:31 AM
  #2  
Registered User
iTrader: (-1)
 
Co_94_PU's Avatar
 
Join Date: Dec 2012
Location: Colorado
Posts: 5,433
Likes: 0
Received 554 Likes on 452 Posts
Always helpful to put some text with a photo..

In the first image, you are trying to show the tip of the lower cam lobe?

Looks like the wear starts right near the high point, this could be from improperly adjusted valve clearances. Either combined with lack of oil flow or causing the lack of flow, doesnt matter what pressure you have in the galley if theres no gap/clearance there is no flow so no cooling or lubrication. Aswell pre-ignition could be trying to slam that valve closed.


Bottom line, time for new rocker arms and a cam for sure.
Old 08-12-2018, 10:29 AM
  #3  
Registered User
 
millball's Avatar
 
Join Date: Aug 2013
Location: Southern Arizona
Posts: 4,104
Received 603 Likes on 441 Posts
What brand of motor oil have you been using??? How many miles has the engine run???

The cam lobes are oiled by dipping into oil that is held in dams in the top of the head.

I have seen an aftermarket head where these oil dams would not hold oil as the OEM heads do.
Old 08-12-2018, 06:11 PM
  #4  
Registered User
iTrader: (1)
 
thefishguy77's Avatar
 
Join Date: Dec 2011
Location: sammamish, wa.
Posts: 2,179
Likes: 0
Received 62 Likes on 57 Posts
Also seen soft aftermarket cams. Or bad break-in and let to an premature problem as well
Old 08-12-2018, 08:47 PM
  #5  
Registered User
Thread Starter
 
shisha1999's Avatar
 
Join Date: Jun 2015
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
Co_94_PU...yes that is the tip.

The engine has 171K miles. It runs sluggish as a result of the jacked up cams. I dont recall the motor oil brand that I used, it was a Jiffy lube over 75K miles oil which I believe is Penzoil.

Going to definitely take it to a machine shop for a rebuild.
Old 08-14-2018, 04:56 PM
  #6  
Registered User
 
SENOR NOODLES's Avatar
 
Join Date: Apr 2018
Location: Fair Oaks, CA
Posts: 97
Likes: 0
Received 9 Likes on 9 Posts
Your rod bearings and main bearings probably do not look much better. I just dealt with this. loose timing chain tensioner, flat cam, worn bearings, wasted crank. Even with new cam, no oil pressure, engine still ran great, just smoked. I would rebuild.
Old 09-27-2018, 06:03 PM
  #7  
Registered User
Thread Starter
 
shisha1999's Avatar
 
Join Date: Jun 2015
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
Decided to rebuild both the head and engine. Been driving it for two weeks now and drives much better. Can climb hills without problems and accelerates easier. So far looking good and just need to continue driving more to break in the engine. The only thing that stands out is the engine temp indicator gets to operating temp very quickly when I start the truck.
Old 09-27-2018, 07:35 PM
  #8  
Registered User
iTrader: (-1)
 
Co_94_PU's Avatar
 
Join Date: Dec 2012
Location: Colorado
Posts: 5,433
Likes: 0
Received 554 Likes on 452 Posts
Related

I read post by one of "those guys", Ted Todd or maybe Jim, the other day.

They were discussing how the tip of the rocker arm shouldn't be in contact with the cam as it causes premature wear..

Essentially what this translates to is if the rocker arm surface is overly flat there is to much contact pressure put on the cam lobe.
(Edit)
The test for this is to inspect the contact pattern, the solution is to replace the rocker.

Last edited by Co_94_PU; 09-28-2018 at 03:36 AM.
Old 09-27-2018, 08:48 PM
  #9  
Registered User
Thread Starter
 
shisha1999's Avatar
 
Join Date: Jun 2015
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
Would that be caused by a loose timing chain?

Below are some pics of the replaced parts.




Old 09-28-2018, 03:38 AM
  #10  
Registered User
iTrader: (-1)
 
Co_94_PU's Avatar
 
Join Date: Dec 2012
Location: Colorado
Posts: 5,433
Likes: 0
Received 554 Likes on 452 Posts
Updated the previous post.

I don't think the chain has relevance for that issue, but you may have been asking about some things in you last set of photos.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Dave JR
86-95 Trucks & 4Runners
2
11-10-2014 07:05 AM
bmktw2
84-85 Trucks & 4Runners
7
05-16-2013 06:45 PM
Berniep
Newbie Tech Section
4
09-15-2008 03:14 AM
tomasp
General Vehicle Related Topics (Non Year Related)
0
08-29-2006 03:56 AM
guitarsncars
95.5-2004 Tacomas & 96-2002 4Runners
4
08-02-2003 12:11 AM



Quick Reply: Cam Lobe Ground Down



All times are GMT -8. The time now is 08:49 AM.