Engine Knock?

[Prospect]

I recently picked up a 90 GT, and when I bought it, it sounded great, ran good and I thought everything was fine. Since I bought it, I barely have driven it because of all of the snow we've been getting, but now it is making a knocking sound. Any idea what this could be? I'm waiting for a TFS top end kit to come in so I'm hoping this isn't bottom end.


View: http://www.youtube.com/watch?v=JoUpSaibYos

 

[Grabbin' Asphalt]

Oh man, that sounds kinda deep, not like rocker chatter

 

[Grabbin' Asphalt]

you can grab a hose and listen the old school way and try and hone in on it, but any bearing cam, rod, crank will require you know what.

 

[Prospect]

You think it's a bearing?

 

[84Ttop]

Doesn't sounds good. Obviously hard to pin point in a video but leads me tonlean towards classic rod knock...

 

[madspeed]

could be rocker hitting the baffles inside those non efi valve covers

 

[Grabbin' Asphalt]

could be rocker hitting the baffles inside those non efi valve covers

cannot hurt to look at that top shelf clearance, probably would be marks on the underside of the covers, ...hope thats it!!

 

[madspeed]

they look like standard chrome stamped steel valve cover for a non efi sbf. They likely have baffles inside them that do not provide the necessary clearance for roller rockers. Easy to check

 

[Prospect]

When I first bought the car it didn't make any sort of sound like this. If it were the covers, wouldn't it always sound like this?

 

[Prospect]

Also, the guy I bought it from did tell me that he had an exhaust leak that he had fixed. Could it be a loose header?

 

[A5literMan]

Pull the valve covers and check and see if the rockers are hitting the baffles like mad speed recommended. You can also check for an exhaust leak(doesn't really sound like it though). If they both check out fine I fear it's rebuild time

 

[Prospect]

I was pulling the whole motor out anyway, and this may be a blessing in disguise

 

[Prospect]

http://www.summitracing.com/parts/fem-mhp173-300/overview/make/ford

Good for a rebuild?

 

[Fordfreak93]

I've seen the harmonic balancer come apart and make a noise similar to that. The balancer has a rubber sleeve inside that wears out or pushes itself out and it causes a god awful noise when it does. Sounded like the engine was coming apart! Sometimes the rubber will stick out or you can see it wobble. Might be worth a look...

 

[Prospect]

I'll take another video of the balancer. My dad actually thinks it's either the balancer or a bearing down low as well.

 

[Fordfreak93]

Winter can be hell on rubber parts, definitely check it out. The rubber wears out and causes the inner and outer rings to "knock" together. This is not a mustang balancer, but you get the idea

 

[Prospect]

Yeah, especially this winter. This winter has been brutal on this car. Cracked the windshield, sagged the door preventing it from shutting, and now the motor. This all happened within 2 weeks from buying it.

 

[Grabbin' Asphalt]

I've seen the harmonic balancer come apart and make a noise similar to that. The balancer has a rubber sleeve inside that wears out or pushes itself out and it causes a god awful noise when it does. Sounded like the engine was coming apart! Sometimes the rubber will stick out or you can see it wobble. Might be worth a look...

Yup very possible

 

[89llx]

do you see copper metal flake in the oil on the dip stick,, look at it in the sun

 

[mikestang63]

cut the oil filter in half. Pray you don't see gold, copper, or silver. Since you are taking the motor out anyway, once you pull the pan and a bearing cap let us know.