Start up knock
 

My '91 has always knocked a little upon startup. It fades away after a couple seconds. This year when I started it the knock was much louder & lasted much longer. Now it is doing the extra loud knock on all start ups.

I have had some experience with overhead cam engines and I would guess the problem to be cam chain slop. Either one or more chain guides are worn or broken.

Has anyone done this repair before? Any idea of cost?

Dan

Re: Start up knock
 

Which oil filter do you use?
and, please explain, deep knock or a metallic rattle?
Marty

Re: Start up knock
 

My '91 has always had a second or so of rattle, but have noticed it goes away after an oil change. ( Amsoil and AC Delco PF970C ) Once I get around 1000 miles or so on the new oil change, the rattle slowly comes back.....

Re: Start up knock
 

Try the Bosch 3401 listed below and please report back if this changes it.


Bosch 3401 Premium FILTECH Oil Filter



by Bosch Automotive

/* * Fix for UDP-1061. Average customer reviews has a small extra line on hover * https://omni-grok.amazon.com/xref/sr...teTemplates#40 */ .noUnderline a:hover { text-decoration: none; } 4.6 out of 5 stars 1,879 customer reviews







Price:$9.32 FREE One-Day

• Exclusive FILTECH media technology screens out more harmful contaminants for greater engine protection
• Strong steel base plates and housings prevent warpage, leaks, and poor fit
• Silicone anti-drainback valve ensures a supply of clean oil when the vehicle is started
• High lubricity gasket design provides a tight seal, yet allows for easy removal

› See more product details

Re: Start up knock
 

I use the WIX 51324, the HD filter with the silicone anti-drainback valve. They are supposed to be one of the highest rated filters for this engine.

Re: Start up knock
 

OK,
Rattle or KNOCK?

Re: Start up knock
 

Years ago I had a Lincoln with a 4.6L DOHC engine. It had a failed chain tensioner and the chain slapped against the housing upon startup.
What I am experiencing sounds like just like that.

I ordered the oil filter. It's worth a try.

Re: Start up knock
 

OK, that does sound like tensioner/ chain noise.
Which oil are you using?

Re: Start up knock
 

Change to the Bosch filter now that it is doing it again after 1000 miles.
Just change the filter and let us know what happens.
Marty

Re: Start up knock
 

If isolated to chain rattle at start up and if still somewhat present after new anti-drainback oil filter...this helps some:

https://www.jerrysgaskets.com/housin...ign-90-95-1g4/