Knock cause?

[opelsuby]

A guy in a little town a few miles for me has a (he thinks on the year) a 79 wagon 4wd manual tranny for sale. He says it runs but a little rough. I asked what that meant. He says it starts to knock when it warms up. Any thoughts on the cause for this? If it is decent shape, I may pick it up> Supposed to get pics tomorrow.

 

Any way to isolate the knock or deduce the cause? :-\

[nipper]

Rod knock.

 

With the engine running remove one plug at a time and see if the sound changes.

Also use a wooden dowel or long screwdriver as a stethescope and see if you can trace the noise.

 

 

nipper

[opelsuby]

Rod knock.

 

With the engine running remove one plug at a time and see if the sound changes.

Also use a wooden dowel or long screwdriver as a stethescope and see if you can trace the noise.

 

 

nipper

I asked a guy yesterday and he thought it may be a timing thing. Off a notch maybe:-\ Also, if it was a rod, wouldn't it Knock all the time?

[nipper]

I asked a guy yesterday and he thought it may be a timing thing. Off a notch maybe:-\ Also, if it was a rod, wouldn't it Knock all the time?

 

You would think so, but rod knock gets louder as the engine warms up. The oil thins out and looses some of it's ability to cushion large gaps. Also Rod knock can come and go. I know on my 2.5 it appeared once, disapeared for 2000 miles, then threw a rod.

 

Timing would make a iginition knock, which is a higher pitched noise, but can be just as destructive.

 

nipper