Notices
1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
Sponsored by:
Sponsored by: Moser

Oil Sludge

Thread Tools
 
Search this Thread
 
Old Sep 19, 2015 | 04:54 PM
  #1  
Erik Jaeke's Avatar
Erik Jaeke
Thread Starter
|
Freshman User
Joined: Sep 2015
Posts: 38
Likes: 0
Oil Sludge

Changing the oil in my 1979 400cu. I can see a ton of sludge inside the valve cover. Best ways to clean it? Thanks!
 
Reply
Old Sep 19, 2015 | 06:08 PM
  #2  
Blue and White's Avatar
Blue and White
Postmaster
Joined: Nov 2011
Posts: 2,553
Likes: 10
Best is to pull the VC's and clean it out with rags/shop vac. Plug the oil return drains first so no chunks drop down. Run for 50-100 miles then change oil again with high detergent oil like diesel engine oil. Change frequently after that (eg every 500 miles) for several changes to finish cleaning.

Sludge can be caused by extended oil changes, incorrect thermostat (180 minimum, 190-195 preferred), PCV inoperative or short trips especially in cold weather.
 
Reply
Old Sep 19, 2015 | 06:34 PM
  #3  
HIO Silver's Avatar
HIO Silver
Fleet Owner
Joined: Dec 2009
Posts: 20,678
Likes: 83
From: NorCal
... also caused by a dusty conditions and a lack of air filter oil/oil filter changes... generally referred to as crummy maintenance practices.
 
Reply
Old Sep 19, 2015 | 06:48 PM
  #4  
Erik Jaeke's Avatar
Erik Jaeke
Thread Starter
|
Freshman User
Joined: Sep 2015
Posts: 38
Likes: 0
Originally Posted by HIO Silver
... also caused by a dusty conditions and a lack of air filter oil/oil filter changes... generally referred to as crummy maintenance practices.
Thanks guys. Just bought it.... It had been sitting for 5 years. Trying to get her going
 
Reply
Old Sep 19, 2015 | 07:05 PM
  #5  
Erik Jaeke's Avatar
Erik Jaeke
Thread Starter
|
Freshman User
Joined: Sep 2015
Posts: 38
Likes: 0


Can I use solvent to help clean?
 
Reply
Old Sep 19, 2015 | 07:35 PM
  #6  
HIO Silver's Avatar
HIO Silver
Fleet Owner
Joined: Dec 2009
Posts: 20,678
Likes: 83
From: NorCal
Yeah but plug the oil return holes and you'll need to clean up all the big chunks that are dislodged. I think hot runs and frequent filter changes would be a better approach at this point. Change the oil and then just change the filter after 100 miles. Top it off and repeat. Monitor.
 
Reply
Old Sep 21, 2015 | 10:44 AM
  #7  
Erik Jaeke's Avatar
Erik Jaeke
Thread Starter
|
Freshman User
Joined: Sep 2015
Posts: 38
Likes: 0
Originally Posted by HIO Silver
Yeah but plug the oil return holes and you'll need to clean up all the big chunks that are dislodged. I think hot runs and frequent filter changes would be a better approach at this point. Change the oil and then just change the filter after 100 miles. Top it off and repeat. Monitor.
Yeah agreed. I will replace gaskets on both VCs, (after cleaning the inside of both VCs). Oil up, drive for a while, then change oil again. Should help. The motor runs really clean right now, so that's good at least!

Thanks all
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Fefanatic
1999 - 2016 Super Duty
8
Feb 5, 2018 03:12 PM
fmuguira
2017 - 2022 Super Duty
2
Sep 1, 2017 08:06 AM
Shawn MacAnanny
1994.5 - 1997 7.3L Power Stroke Diesel
16
Feb 4, 2017 10:58 AM
CheaperJeeper
Pre-Power Stroke Diesel (7.3L IDI & 6.9L)
48
May 22, 2009 08:05 PM
priley
Oil & Lubrication
2
Sep 17, 2001 07:46 PM




All times are GMT -5. The time now is 06:45 PM.

story-0
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-1
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-2
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-3
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-4
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-5
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-6
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-7
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-8
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-9
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE