1997 Ranger 4.0 OHV 90K miles, regular oil/filter changes at 3000 miles,
5W-30, all emissions control items replaced or checked to be operating normally

I was having CEL 171/174 problems, very rough idle and a small coolant leak in rear of engine under valve cover passenger side.
After reading threads on this forum thought my problem was the upper/lower manifold gaskets, performed replacement using Rockledge's how to info.
Takes time but all seemed to be pretty straight forward.

Put it all back together the first time, the engine ran great and quiet (after I put the spark plug wires on the correct plugs, I had 2 crossed) except for I had an oil leak on the rear of the left driver's side valve cover and a loud intermittent clicking noise, did not change with rpm.

Took off the upper intake and valve cover, retorqued lower manifold and upper manifold as I discovered I did not have torque set correctly, off abit, too light, applied some black ultra RTV to rear corner of leaking valve cover gasket on the bottom and alittle bit on top near bolt holes, torqued bolts (the first time I was torqued too light)

I attributed the loud clicking noise to slude buildup in lifters as there was alot of it and I wanted to clean it out but didn't want to stir all that stuff up and left it alone as much as possible, but with putting down the valve covers in such a tight space, I'm sure some was knocked loose.

Put it back together again, engine runs smooth and quiet, except for this loud clicking noise, which after about 5 minutes of idling, went away and no leaks.
Went for road test and at about 25mph oil pressure gauge started to go up and down and I heard valve/lifter chatter right away, went to 40mph and lost all pressure and more valve/lifter noise, pulled over stopped, idle in neutral, pressure started to come back and then back down. shut the engine off and restarted, oil pressure according to gauge back to normal, no lifter noise, even when revving up abit. Put back into drive, same as before, noise and no pressure.

I used the Fel-Pro Perma-Dry-Plus gasket set which has the rubber ends for the lower manifold now instead of the cork as before and are in two separate pieces instead of one with the cross bars as the old one was, so each side must be positioned and was the only concern I had as to how to keep the gaskets positioned while lowering the lower manifold on top with the sealant still wet and they did tend to slip around. I also did not use guide pins to set the manifold as I did not discover I needed them until I went to put it on, but when I set it down, it seemed to go right into place without moving it much and bolted up fine.

Question: If the gaskets are out of position, would they clog oil ports somehow? If they are out of position, it can't be much as they would be sticking out of one of the ends, however they could not exactly be centered into position.

I am going to change the oil and the oil filter tomorrow, as maybe it could be some sludge in the oil and clogged the filter?

Any insight to this anyone? I must have my truck running, been without it for a week now.

 

Is There Any Water In The Oil Or Is The Oil Level High ?

 

I hope you changed oil & filter after gasket change! and also hope you do not have a fram filter on it.

I have found those filters do not bypass when getting full of junk. before anything else change oil and use a motorcraft or purolator filter.

What may have happened is even though you did your best not to disturb the gunk in there, when you pulled the intake some stuff still came loose and worked its way through.

 

If the lower intake and/or gasket is not seated correctly, then there could indeed be loss of oil pressure, not to mention low compression and potential coolant seepage into the cylinders.

Another thing to consider is that something other than dirt fell into the engine, such as a small nut or bolt. You didn't happen to come up short in that category, did you? This is always one of my stress points, because I have a tendency of knocking things around and losing track of them when I'm working in tight quarters like that.

In any event, it sounds like you will have to go back in again. Once you have the lower intake off you might try cranking the motor just to make sure you don't hear any more noises out of the ordinary (which would probably mean something got dropped into a port or the rocker assemblies).

If all seems OK, when you put it back together, I strongly suggest using the Ford lower intake gasket (one-piece, rigid metal, rubber ends) which has to be a lot easier to set and hold in place than the Fel-Pro you described.

Good luck.

 

Thanks for the replies.

I am changing the oil and oil filter next look at the oil for gunk and to see if any water got into the oil as water did gush out when I removed the lower intake. I am putting on a new Motorcraft filter as recommended by FTE, I have been using Purelator filters.

As far as dropping anything in the engine, I am certain that didn't happen as I kept everything covered with old T-shirts as I went and no bolts or anything missing.

If that doesn't work then I will remove everything and check the lower gasket positions. These gaskets do have a metal tab which centers and hangs off each intake port and helps to determine position.

I will let you know what happens.

Thanks again for replying so soon. I go nuts when my truck doesn't run.

 

If you have to go back in & open it up again, you might consider using a shop vac to suck up & remove the sludge on the top end, maybe rod out the oil returns, then drop the pan to clean it out & checking the oil pump screen, to make sure it isn't clogged up, before adding new oil & filter & runnng it again.

Are you sure the PCV system is/has been functioniong properly????

If so, then it would be interesting to know what oil & filter you have been using, that would sludge an engine up like this, with 3K OCI's ??????

 

I have a feeling the biggest problem is water in the oil.

Let's hope you haven't damaged your bearings. For future reference, change the oil after any kind of engine repair and BEFORE starting the engine.

 

I changed the oil and filter and things do not look good.

There is no water in the oil but I did find a piece of what looks to be metal and it does stick very lightly to a magnet, plus there were other fine particles in the bottom of the catch pan I used, kind of like sand, maybe a 100 or so very fine grains but the magnet will not pick them up. Some sludge was present but not much.

I started the engine after the oil change but shut if off immediately as there was no oil pressure showing and the lifters were making noise or something was making noise.

If I dropped something in the engine, I have not a clue would it could have been, it just doesn't make sense to me at this point.

I am going to take a break on it for now before I start to remove everything and check the metal lower gaskets which may have slipped.

I would like to drop the oil pan as well but according to a Haynes Manual I have you must pull the engine to do so and I will have to find someone to do that for me, unless I can drop it without pulling the engine.

 

just remove pick up from inside oil pan . then you can take your new oil pan gasket and weave it between pick up and motor. Btw im sure this post is ancient".

 

I just received an email from this post I put on the site. I had cleaned the engine as much as possible with kerosene and had a mechanic replace the oil pump and pick up screen for $650.00 back then.
I still run this truck everyday and now has 157000 miles and it still runs great with no oil pressure issues. I did have to replace the ford intake manifold gasket again about 5 years ago and replaced it with a Fel-Pro.
No new issues to date and no antifreeze leaking into the engine.

 

Ok, good feedback & to hear you were successful in resurrecting this puppy 11 years ago & all still seems well.

 

pressure! Know this is an old post but for future reference I'm a little concerned that there's quite a bit of sludge in an engine with 90000 miles and has been serviced on a regular basis...at this point pump could just be giving up if it's been let go on service main barings could be worn that will cause loss of pressure and can happen if not kept serviced! I have a 99 3.0 and 2004 4.0 with 232000 on it and there's absolutely no sludge but it was a one owner that I knew and it was on a strick service schedule and still runs like a top! I'm just saying if someone before you drove it and never really changed oil that may be the issue!