Real Time Help: Engine Knock

[CruisinMT]

I've searched the threads and have eliminated a few things. I started to pull the plug wires to check how it affected the knock. I found on #4 the knock stopped when I pulled the plug wire. So what does this mean?

 

[matt.mcinnes]

I've searched the threads and have eliminated a few things. I started to pull the plug wires to check how it affected the knock. I found on #4 the knock stopped when I pulled the plug wire. So what does this mean?

I would say it means your putting less strain on No4 as its not firing and that the problem lies within.

 

[CruisinMT]

It's weird I only hear the knock at idle and I do not hear it when rpm's increase.

 

[Joe Egolf]

knock

I saw on another post the other day ref knock ,to check and be sure you do not have a broken motor mount???

 

[JC39232]

I saw on another post the other day ref knock ,to check and be sure you do not have a broken motor mount???

Might try out thread:

https://forum.ih8mud.com/40-55-series-tech/184004-sounds-like-lower-end-rod-knock-but-only-idle.html

sounds like the same issue

 

[Pighead]

Sometimes an exhaust leak sounds like an engine knock...re-torque your manifold?

 

[CruisinMT]

Sometimes an exhaust leak sounds like an engine knock...re-torque your manifold?

If it was an exhaust leak would it stop when the plug wire is pulled?

 

[rsbcruiser]

It's weird I only hear the knock at idle and I do not hear it when rpm's increase.

As your engine rpms' increase the oil pressure builds up. The greater pressure and flow fills the bearing with oil. Maybe try a heavier weight oil. See if that does it for you.

 

[Pighead]

If it was an exhaust leak would it stop when the plug wire is pulled?

I think it would...if it was a leak at the manifold, and only the one was leaky.

 

[Degnol]

Timing gears can make a knocking sound at idle that disappears off-idle. I think it is caused by the thrust of the cam being worn and out of spec.