Engine Knocking Sound From Upper Intake Or Dside Valve Cover

[Todd Taylor]

After sitting idle for 13 years I decided to make my 1986 Mustang run again. I replaced the gas tank and pump and got it fired up. I then decided to change the valve cover gaskets since they were leaking really bad. I removed the upper intake, covered the holes, and took off the cork valve cover gaskets. I replaced the gaskets with metal/rubber ones and bolted everything back together. Upon starting the engine there was a knocking sound coming from the motor. The best I can tell is that it is coming from upper intake area or the drivers side valve cover. Any suggestions on where to start would be greatly appreciated.

 

[jrichker]

Pull the valve cover off the noisy side. You will either find something loose or a rocker rubbing up against the valve cover. Look for evidence of scrape marks inside the valve cover.

 

[Todd Taylor]

I pulled it back off. Looks like there is some fresh wear on the topside of the cover. Near the middle bolt hole. Looks like there is small cracks in it as well that don't go all the way through the the cover. Why would replacing the valve cover gasket cause this?

 

[Todd Taylor]

This is the two middle bolt holes.

 

[Todd Taylor]

Ok I think I figured this thing out. I discovered it's not a valve cover issue. I think it is a lifter. Upon listening to it knock, I increased the RPMs and the knocking subsided. When listening to the top of the manifold the noise occurs during the firing order and decreases the warmer it gets. Any other ideas or suggestion?

 

[mikestang63]

pour about 8 ounces of MMO in the oil and it should free up the sticky lifters

 

[Davedacarpainter]

Ok I think I figured this thing out. I discovered it's not a valve cover issue. I think it is a lifter. Upon listening to it knock, I increased the RPMs and the knocking subsided. When listening to the top of the manifold the noise occurs during the firing order and decreases the warmer it gets. Any other ideas or suggestion?

Hey Todd, I'm in broken arrow, about 81st and Garnett. Whereabouts are you?

 

[stykthyn]

Those valve covers just look like they've been over torqued.

 

[madspeed]

any marking to the underside of the valve vover? could be a rocker touching the vc

 

[Todd Taylor]

Hey Todd, I'm in broken arrow, about 81st and Garnett. Whereabouts are you?

Skiatook. I guess you paint cars based on you name?

 

[Davedacarpainter]

Skiatook. I guess you paint cars based on you name?

Yeah, it's a dumb name I had to pick about 14 years ago for eBay. They had somebody just named Dave, another account with my last name, they even had someone called davethecarpainter! I was running out of imagination, soooo...
I work at Chris Nikel's body shop in BA.
I need to hook up with a local group, but I thought I would try to have a driving mustang first.

 

[Todd Taylor]

Do you paint cars on the side or just at work? I just got my mustang ruining after 13 years. Just been sitting in the garage gathering dust. It is going to take awhile to get it up to where I want it to be, but I have enjoyed working on it over the last month. Problem is I don't have an unlimited budget and as I have found out older car parts cost money. I work in Tulsa as a police officer and have for the last 16 years. Is that red hood off of your car. It looks good. Is the GT emblem vinyl or painted on?

 

[Todd Taylor]

any marking to the underside of the valve vover? could be a rocker touching the vc

There is one mark on the under side. When listening to it with a screwdriver I'm sure it's not the valve covers knocking. If I listen to it in the intake right behind the distributor I can hear a distinct ticking noise. My guess is the lifters or cam. Definitely in the top of the motor though.

 

[Todd Taylor]

Those valve covers just look like they've been over torqued.

That was my thoughts as well. Probably gets some aftermarket ones at some point.

 

[stykthyn]

I like the explorer valve covers. Steel instead of aluminum and they clear roller rockers.