Help needed, 1998 F/150 No power/pops

Maintenance/Repairs
1

Hi,

Need help, My son ran his 1998 F/150 very low on oil it stop, will start has but has no power,pops, but no oil on plugs or anything coming put of the tail pipe. He was told it needed a new engine. Can anyone give us anything to check.



Thanks

2

Define how low on oil. If it’s not on the dipstick then chances are he does need a new engine. The problem will be in the crankshaft, crank bearings, etc. and so you will not see a problem with oil on the plugs or out the tailpipe.

The first thing I would do is perform an oil pressure test with an external gauge and follow that up (maybe) with a compression test.

3

I think it was like 4 gt. low.

4

Cant relate why it would be “popping” through the intake or out the tailpipe due to low oil. Now low power sure (loss of compression). Maybe a valve siezed in a guide?

5

Let’s get this clear. The engine stopped, you checked the oil and it was low? Find out if the OIL light or gauge works and if it was on or all the way low when the engine stopped.

If it turns out you need a new engine, you don’t need a new or rebuilt engine. What you will want to do is get a salvaged engine. They are plentiful and inexpensive. Shop around. Several years will interchange the long block.

6

At 4 quarts down this means what little oil remains is in suspension. The oil pump was probably sucking air and what little oil film is on the crankshaft journals will disappear in a few seconds.

Step one should be testing the oil pressure with an external gauge. This should tell you if there is a serious crankshaft and bearing problem.

At first I wasn’t too sure about the popping but got to thinking that this could be caused by a cylinder miss due to a collapsed valve lash adjuster, or an adjuster thrown out of the rocker arm. The adjusters rely on oil pressure to stay pumped up and if there’s no oil pressure…

Clattering adjusters due to lack of oil pressure can damage the valve adjusters and the camshaft lobes. Possibly another reason to need an engine; either new, rebuilt, or used. Probably the latter IMO.

7

Where do you look for a salvaged engine and what make and years can they come off of, This is a 4.6 V/8 windsor, stick