Lifter noise or exhaust leak?

[bookman]

I have a 2000 XLT AWD with a 5.0 engine. When I start the engine, there is a rather loud tapping noise coming from the front end of the passenger side of the engine. It begins to quieten after a minute or two of running, but does not go away completely.

I first thought it might have been an exhaust leak, then I decided it sounded more like a lifter. Now I find several posts on this forum about a passenger side exhaust leak. That gives me reason to doubt the lifter possibility.

My Explorer has cast manifolds. Is the infamous exhaust leak also common on a 2000 with cast manifolds, or is it just on welded manifolds?

Also I have read about a bad EGR sometimes causing similar noises. I know nothing about the EGR - where it is, how to check it for failure, how to replace it, etc..

I would appreciate any input anyone has for me.

Thanks.

Bookman

 

[bookman]

Anyone have any ideas or comments on this?

Thanks.

 

[Mikeri]

Had the exact same thing on the front of the engine on the driver's side. Found a bolt from the exahaust manifold had fell out. I suspect a manifold leak. Search "5.0 exhaust manifol".

 

[nssj2]

highly recommend checking your egr tube. when its cold, start it up and see if you can feel little puffs of exhaust from the tube or the manifolds. you only have about a minute before things get too hot.

 

[bookman]

Mikeri, I followed your suggestion and sure enough, the front manifold bolt is backed out so that the nut lacks more than 1/4 inch being tight. The nut seems to be threaded as far down on the stud as it could be, and from what I can tell, the stud itself is backed out.

I don't remember ever messing with manifold bolts, especially any that are covered with rust. Are they normally hard to get out and replace or to tighten? That is, without twisting them off? I'm feeling a bit apprehensive about trying to tighten this one for fear of twisting it off.

Thanks.

Bookman

 

[Mikeri]

Do be careful. Hit with PB blaster for a few days. Get that rust loosened up. Then, call a Ford Parts Dept, tell them the exact location of the bolt, and buy the replacement. Expensive, like 8 bucks. Put some locktite on it when you screw it back in. Was it a 15mm? Can't remember off hand. Have fun.