unfortunately I did not notice engine running low on oil.....wife said gage was bouncing between no pressure and some pressure when arriving at ball field....started truck up after game and heard a clacking noise....checked it out and was too low on oil.....filled up and now I hear clacking when revving up engine at the higher rpms and stops when letting off gas.....took it for a spin and I can't hear anything between 1000-2000 rpm under load.....at about 2000 I can start to hear clacking and by 3000 its really hammering.....let off the gas an it disappears.....fearing the worse.....oil pump or main bearings????? Oil pressure is good and steady and no leaks anywhere, normal power.......normally don't need high rpms with this engine to drive around so still using it.....

any suggestions????

 

Change oil with synthetic and add a qt. of Lucas full syn oil stabilizer. If that don't help start saving for a motor. Do you have a stethoscope to listen for the noise, if you can find it you may be able to save it. I have seen Lucas quiet up some pretty noisy motors its good stuff.

 

Could be a rod bearing. A main bearing will *usually* make your oil pressure fluctuate.

 

You're probably right. I guess I'm going to be getting a manual and seeing what it will take to change the rod bearings. Don't think it will be too bad.....hopefully....

anyone change out rod bearings with engine in the truck???

 

With the oil pressure fluctuating and the engine clacking I would suspect a really bad crank as well as both rod and mains gone bad.
From your description I think just bearing replacement is wishful thinking at this point. You're looking at a complete overhaul or replacement of the engine. A Ford reman would be a good choice when you consider the warrantee.

 

Don't run the engine if you want to have a chance of saving it.

 

Keep an eye on Craigslist. Your goal? A totaled truck being parted out.
I scored a complete 3V with only 6K miles for $2K....
It was out of a class A motorhome that caught on fire. I guess I was the only one that realized the basic engine was the same so I got a deal.
Yes, even a 3V short block will work for you. The heads are radically different, but your heads may be fine, especially if you were running a premium oil in good condition.

 

That could be one main bearing bad.... a rod knock usually knocks at all RPMs.

Either way, it's not good. Either drive it till it drops (and be prepared for it) or pull it and fix it or get another engine.

 

thanks for the replies.......ran a flush and changed the oil......definitely a knock at idle but not real loud.....already started disassembly to get the oil pan off and see what the damage is......stuck at removing the y-pipe at the moment.....says to loosen the nuts at the unions.....hahahaha....I would if they still existed!!!.....first time working on a north eastern vehicle in 15 years....been living in the south where you can still remove every bolt off a 20 year old car....oh well I guess I will be looking to buy a cutting torch (unless someone has a better idea or cheaper way to do it???????)....ground one off with my grinder,but can't reach the other places.......

another engine won't be an option for me right now so I will be looking for suggestions on rebuilding...I will report back once I have a chance to look over and take a few snap shots......It doesn't look real bad to pull this engine......almost half way there anyway.....

 

There's one thing to watch out for with an oil-starved overhead-cam engine - the cam journals in the heads. Pull the valve covers, and one at a time, pull the cam journals off and see if they are badly scored/scraped/black and the cam itself is good. If they are clean, just do whatever you need to do to the bottom end.

I haven't taken apart an oil-starved Ford modular yet, but have done plenty of Triumph TR7's which use basically the same type of cam journal in an aluminum head. It ain't pretty.

 

Yea, I would torch the Y pipe and put it back togather with one off Ebay.
I have seen the heads on a 4.6 that was run with no oil and Art's not kidding, Its BAD.

Were are you located Cooper?

 

Well, bought an air chisel for $15 and a chisel set and got the y-pipe off. The pan won't come out but I have enough room to check everything out. First rod at the front of the engine was so bad I could move it back and forth with my hand. Rod is a different color than all the rest so assuming it got hot. Rod is spun and the ID of the bearing is worn pretty bad. No significant scratches, gouges or burn marks on the crank though.

I don't have an option for a rebuild at the moment so I am going to take a crack at just replacing the bearing. I've read a little into it and its can be done but very iffy. I know everyone recommends not doing, but I have nothing to lose except some time and a few bucks. I know the risks. If you were to do this, what would you check, polish, buy, etc????? Looking for useful suggestions.

 

From your description of the rod it is important for you to know that the bearings sort of snap into place and do not come out freely (or fall out) of the rod. The outside of the bearings are all the same size to match the OEM rod inside diameter and I believe you will find that the rod is misshapen to the point where the bearing will not stay in place. For the repair you are considering you will need some bearing shim stock along with the bearings that are sized to fit the journal. The shim stock is not easy to find but some old time engine repair shops may have some in stock. Shimming the bearings is a practice that just isn't done any more since reconditioned rods are easily available for all but the newest Ford engines that have the cracked rod separation, they must be replaced. Don't forget to buy new rod bolts as the ones you have are made for one time tightening only. Good luck with your project and let us know how it turns out.

 

Yes sir. A steel cam riding on aluminum (with no bearings) has got to have oil and the heads are a lot farther from the oil pump than the crank.

I'd pull the valve covers and look at the top end before starting work on the bottom end.

The bearings are obviously softer than the journals. Did you make it all the way through the bearing material? You can use a micrometer and check around the diameter of the journals to make shure they are within spec.

All kinds of crap probably got pumped through the engine. Some frequent oil changes after the repair would be a good idea.

 

Alright, now we're talking......it did not go through the bearing material, but does look about half way from the ID. I read some where that something has to be done to make up for some possible lost material on the rods due to the spinning so thanks for the shim stock idea......I was thinking of pulling the next rod over to have a look and possibly mic everything there for comparison....The OD of the bearing does look like it rotated, but I can still read all the markings.

I bought some 1500 grit paper to polish up the journal and they said to wrap the journal and use shoe string to keep it even.....use a little oil with it and plug the oil hole before doing so. I figure I would start high and go lower on the grit if I needed.

I bought some plastigage as an additional inspection tool.

Since I am already this far, I am going to work and finish up the bottom end and then check the top end and hope for the best.

Anything else you can think of???