Engine noise question

[yodabiri]

I took the mustang on a "maiden" voyage from Stockton to Sacramento (45 mile distance), to pick up some parts and also see how good the mileage is on the freeway. As I was driving for 25 minutes or so I started hearing a tapping noise which got worse with time. It sounded like a lifter was stuck, but it sounded like it was coming from every cylinder. So I coasted down to 50 and the sound slowly went away, so I thought maybe the problem resolved itself. No such luck, when I got to my destination the engine started sounding like a really loud deisel. It really sounded like all of the lifters were getting stuck. the sound refused to go away so I didnt want to chance it, and called AAA and got the car towed back home. I am not sure but it sounds like there isnt oil pressure and the lifters are getting stuck, but since it has happened before and went away I really cannot explain it. Has anybody had such an experience or heard of this happening? I am going to take it in to a shop next week to have them work on it, so any help or advice beforehand would be greatly appreciated. Almost forgot, I started it this morning and it is still tapping but not as loudly, and it has ~4.5 quarts of oil in there.

Andy

 

[Junk-Falcon]

sounds like loss of oil psi , i have seen the valve seals break and on a fast run they ( little pices of broken seals )pluged the pickup screen on the oil pump ,, do you have a gage? thats ware i would start is see what the psi is

 

[tony1963]

I agree. Sounds like a plugged oil pickup screen or very thin oil. You didn't use 5-20 did you?

 

[Asa]

compression test?

any idea how new/old the engine is, and it's general condition?

 

[JackFish]

I'd pull the valve cover and have a look at the valve train too.
Maybe you can check the pump - if you remove the dizzy and rotate the oil pump shaft you should see some oil coming out of the top end.

 

[66 Fastback]

Check the oil level too. Low oil can lead to noisy lifters.

My old Lincoln had sat for years and when I started up it sounded like a diesel, and it lacked power. Turned out the valves were stuck and when I pulled the rocker arms, 7 of the 8 push rods were bent. I doubt that is your problem, but if you all of a sudden lost power too, something similar could have happened.
Doug

 

[yodabiri]

To address some of the things mentioned. I checked the oil and it seems like its is quite high, plus I recently added half a quart of 10-40 (same oil that I always use). I dont have a oil pressure guage, but I should probably get one. Could I test if there is oil getting to the lifters by taking off the valve cover and cranking the engine over to see if oil flows up to the valvetrain? Also i did notice a loss in power when the engine was clicking the loudest, but also when I got it back to the house from Sacramento, I drove it down the driveway (it still clicked pretty loudly), but it seemed to have the normal amount of power. I sure hope that the pushrods arent bent, I would rather not have to buy new ones. Also I heard about a pressure relief valve on the oil pump, and that it might get stuck open and cause a loss in oil pressure. Is this a possibility?

Thanks for the responses!