logo

Go Back   4x4 Community Forum > General Category > Vehicle & Technical Chat

4x4Community






Vehicle & Technical Chat Only on topic posts allowed, all off topic posts will be removed.
Off topic posts to be restricted to General Chat.

 Image

Reply
 
Thread Tools Display Modes
  #1  
Old 04-03-10, 07:43 AM
Nys's Avatar
Nys Nys is offline
Member
 
Join Date: Feb 2009
Location: Windhoek
Age: 31
Posts: 1,610
Default Engine Knock


Good day all,

I did a search on the forum but could not find what I was looking for, thus please bear with me as I try and upgrade my "technical knowledge".

I have read a lot of reports about diesel engine knock and how bad this can be for the engine etc.

Can anybody please explain to me:

1. What does a knock on a diesel engine sound like? and
2. What is the cause of the knock?
3. If there is a knock, how/what are the "remedies"?

I am trying to ascertain as as much knowledge as possible because, as you guys know, I'd rather go to a dealer armed with possible causes than allowing them to search for a problem.

Not that there is anything wrong at the moment
Still loving the D4D. Can't wait to try her out in the dunes

Thanks guys

__________________
Me: Mitsubishi Triton V6 D/C
SWAMBO: VW Polo Classic 1.6

Reply With Quote
  #2  
Old 04-03-10, 07:53 AM
Henris's Avatar
Henris Henris is offline
Commercial Member: Cobrax
 
Join Date: Apr 2007
Location: Nigel
Age: 53
Posts: 12,185
Default

The knock will be more prominent when the engine is cold. But it is not a problem. The thing to know is to be able to distinguish between a diesel knock and an engine knock. The one is fine. The other is fatal.

__________________
LC 78 Troopie 1HD-FTE

Reply With Quote
  #3  
Old 04-03-10, 09:00 AM
Nys's Avatar
Nys Nys is offline
Member
 
Join Date: Feb 2009
Location: Windhoek
Age: 31
Posts: 1,610
Default

Thanks Henris,

I take it the engine knock is the one that is fatal?
How does one know when your engine has a knock. Is it a specific sound/feeling from the engine?

__________________
Me: Mitsubishi Triton V6 D/C
SWAMBO: VW Polo Classic 1.6

Reply With Quote
  #4  
Old 04-03-10, 09:19 AM
Cal Cal is offline
Member
 
Join Date: Sep 2008
Location: Swakopmund
Age: 60
Posts: 117
Default

Nysie,

The "cold" knock disappears when the engine has warmed up. The other one doesn't disappear! And believe you me...you will know when the engine is "KNOCKING"!
Reply With Quote
  #5  
Old 04-03-10, 09:24 AM
JBX Connect JBX Connect is offline
Member
 
Join Date: Jan 2008
Location: Benoni
Age: 55
Posts: 219
Default

Hi Nys, an engine knock will be a very noticible sound lower down in the engine. Because of diesel knock it is more difficult to hear engine knock on a diesel versus petrol.
An engine knock is typically a worn bearing and is best heard when the car is stationary with no load. Lift revs from idle throught he range and typically around 1500 revs and up you will start hearing an engine knock. If it is slight you can use a stetoscope to listen to the low down noises.
it will vary from engine to engine and also pending the severity of the problem.

I suggest you get used to your vehicle and get to know the noises it makes. Any variation will quickly be noticed.

The D4D sub is rock solid and is unlikely to develop an engine knock unless you loose oil.

I just love the D4D typical diesel sound on start up.

__________________
Find the solutions, not the problems.

Reply With Quote
  #6  
Old 04-03-10, 09:42 AM
Nys's Avatar
Nys Nys is offline
Member
 
Join Date: Feb 2009
Location: Windhoek
Age: 31
Posts: 1,610
Default

Thanks for the replies.
What I've gathered so far:

1. It is an engine knock that is fatal to an engine.
2. All diesels have a Diesel knock
3. The diesel knock will be less when the engine reaches operating temp
4. Loss of oil can cause an engine knock
5. It will be difficult to distinguish an engine knock in a diesel engine
6. The D4D engine rocks

My D4D idles the same, whether cold or hot.
When driving, at around 1400 rpm the engine gets audibly louder and stays that way all through the rev range. I haven't been in another, thus I would not know if that is normal. It is very difficult for me to describe the sound, but I can hear it easily. Been like that since I bought it. Is this a "normal" sound for the D4D?

__________________
Me: Mitsubishi Triton V6 D/C
SWAMBO: VW Polo Classic 1.6

Reply With Quote
  #7  
Old 04-03-10, 10:13 AM
FORDJIE's Avatar
FORDJIE FORDJIE is offline
Member
 
Join Date: Feb 2010
Location: Port Alfred
Age: 31
Posts: 48
Default

Nys
The 3l D4D has got a loud diesel knock when it is cold and one accel. hard. Those engine are solid the one I had did 200 000km of towing and had no problems.
Reply With Quote
  #8  
Old 04-03-10, 10:40 AM
Nys's Avatar
Nys Nys is offline
Member
 
Join Date: Feb 2009
Location: Windhoek
Age: 31
Posts: 1,610
Default

Thanks Fordjie,

Like I said, I do not think there is anything wrong with the engine.
I just want to familiarize myself with all the noises so that I can identify a problem if one should present.
Being a second hand car (30k when I bought it) I just want to eliminate all the noises I hear now for future reference.

Gert

__________________
Me: Mitsubishi Triton V6 D/C
SWAMBO: VW Polo Classic 1.6

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Part catalogs & other useful info charlatan Jeep 80 24-05-14 09:18 PM
How to service your vehicle yourself. Koebelwagen Vehicle & Technical Chat 18 03-04-12 07:41 AM
Grand Cherokee Error code Nick47 Jeep 4 30-08-10 01:28 PM
Petrol of Diesel johandewaal Toyota 34 14-04-09 01:00 AM
2-stroke/4-stroke Hybrid Engine SimonB General (non vehicle/technical) 4x4 Discussions 0 26-03-08 12:51 PM




All times are GMT +2. The time now is 04:57 AM.

Disclaimer and Terms of Service

Imvo Trading Solutions CC t/a 4x4Community.
PO Box 29132, Sunridge Park, Port Elizabeth, 6008, South Africa


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Template-Modifications by TMS