Well, this may be the end of my truck. I have an 88 F-150 4x4 with the 302 and M5OD. Today I drove it on the freeway and when I got off the freeway the engine light came on and the engine howled for a few seconds, then stopped dead. I let it sit and it started up and ran fine for a while, then it did it again. I got it to a shop and put a mechanical gauge on it and the pump puts out zero pressure. The pump was replaced and engine was rebuilt only 24K miles ago (2 years) and I never had any oil problems before.

So here is my dilemma: I could replace the oil pump and hope there is no major damage. What would be involved in this? or I could replace the whole engine at great cost to me. What would be the cost of that? I can do all the work myself.

I am really disappointed in the truck now, especially all the problems with the tranny and now the engine.

Somebody give me some advice.

Randy

 

You have several options. How is the rest of the truck? Is the body good, ac work, etc? Is it worth a new engine?

I just bought a new short block from Ford Racing...$1300. Rebuilding your engine would cost between $700 and $1200, depending on how bad it is and how good you want it to be.

I put a new Melling oil pump in my new engine and it locked up, twisting the shaft in two. The shaft hit the crankshaft, which pushed it into the oil pan, creating a pinhole. I'm still evaluating damage.

If I were you and planning to repair it, I would investigate the cause of the oil-pump failure. You need to pull the engine apart and check for spun bearings, metal particles, etc.


Or you could sell the truck as-is to a young fellow who doesn't have much money but needs to learn vehicle maintenance, and let him (her) tinker with it. My philosophy is that it's better to learn on something that needs fixing or building, rather than modifying a new or perfectly running vehicle.

Good luck whatever you decide.
Winford

 

Body needs work. Got many new parts on it: rad, starter, clutch, rear-end, coil, PS hoses, etc. The thing is that I have had so much trouble I am getting upset, I still owe $2000 on it so I can't just give it away.

If I change the pump I will check the bearings and such that I can. I just want it sellable at this point.

Randy

 

I would be surprised if the crankshaft made it through all that without being hurt. I get the impression you might try the lay on your back thing, and pull the pan and try to fix it. Stranger things have happened though.

 

That is my plan. I am very handy with the tools. I did the clutch myself, I can fix just about anything on the truck. What I am wondering is if it is even worth it? I could get a 302 longblock from Trak auto (a rebuild) for pretty cheap. I would just take forever swapping over all the accessories.

I just want to know what my options are.

Randy

 

Not that I recommend this but I have done the same thing, kind of. When I was a teenager, I hit a big rock and holed my oil pan but I drove another 10 miles or so anyway until the engine froze. I replaced the pan, laying on my back in the snow. Put oil in and it started right up.

When I got home I droppped the pan and pulled all the bearing caps. I polished up the bearing journals as best I could, used fine sandpaper in strips wrapped around the journals and wrapped a shoe string around the paper and used the string like a two way pulley. All the journals polished up like new with just a little work. The rear one looked and felt rough, but I had no money so I just put in all new bearings and hoped for the best. I drove that truck for 130,000 miles after that. I check the bearings every couple months and replaced the rear one a couple times, but eventually the rear journal polished up to where it wasn't too bad. This is NOT the proper way to do things but heck it worked for me, just that once.

Not saying this will work for you, I may have been lucky. There may be other problems such as the rings. But if you are really tight for money, maybe this is a thing to try. Be sure to check why the oiling failed on yours. I knew why mine stopped working, dang rock.

I would recommend at least taking a look at the bearings and you can see the lower end the cylinders at the same time. This will at least tell you what was damaged. A rebuild is probably the best bet but if you are tight, who knows.

No Ford truck was hurt learning this lesson, just a rice burner.

Good Luck,

Jim Henderson

 

Heres an update of my repair. (9/10/01)

I discovered that the oil pump is driven off the distributor using a rod inside the engine. This rod sheared near the oil pump and caused my oil failure. I also discovered that the computer will turn off the engine if zero oil pressure is present for more than a few seconds. That is a relief.

So, basically I have no damage that I can see. The pump is totally seized and will be replaced. There aren't any metal shavings in the pan and the pickup doesn't have anything strange in it. It does look like the rod was installed incorrectly by the previous rebuild, it was canted a few degrees off-center which I am sure is wrong.

So, I am replacing the pump and shaft next weekend and should be on the road.

Pan removal: I did have to remove the intake plenum to clear the pan. I also had to remove the exhaust y-pipe and the TB to prevent removing all the hoses and stuff. The pan didn't come free until I removed the pump and pickup tube. The tranny is in the way.

I will update again, and thanks.

Randy

 

One more thing:

I bought the High volume pump and it comes with a new intermediate shaft. The new shaft is substantially beefier than the shaft I removed (I assume stock) so I think that was my problem. The previous rebuilder put a high volume pump on the stock shaft and the shaft couldn't handle the extra forces.

Just another note.

Randy

 

Don't think so.
The oil pump seized like you said then the shaft sheared not the other way around.
A bigger shaft would not have helped a locked/failed oil pump.

Take a closer look at pump to see why it failed.
Sure the shaft broke but first the pump locked up figure why and then you will know what was the cause.

 

I looked at the pump and there are a few small scratches in the two surfaces, but not enough worth worrying about. The oil was very clean and there wasn't anything else in the pan or on the pickup. When I turn the pump by hand it is seized good, when I disassemble the pump it seems to rotate fine. Its like the pump housing is too small for the impeller.

The shaft is definitely bent which contributed to the problem. maybe the pump picked up a small metal shaving and that was all it could handle.

Randy

 

Oh no, I found more. After finally getting the pan off yesterday I discovered stuff in the bottom of the pan. One piece looks like a coiled spring of some sort about 1/16th in diameter tightly coiled and long but ripped into multiple pieces. Piece number two looks like a plug (like a freeze plug) about 1/4" in diameter and it is mangled pretty good. The last piece looks like a thrust washer, copper and thin. All were found in the pan. I cut open the oil filter and it caught nothing so this must be recent damage. It looked like the #2 and #6 piston end caps were dry for a few revolutions but the bearings aren't worn bad so I left them in.

What I want to know is what the hell is piece number one and two? I don't have any idea where these came from.

Anybody got an idea?

I am now totally positive the oil pump chewed on a piece of that spring.

Little help?

Randy

Also, will the truck run normal missing one thrust washer?

 

Those parts sound like the pressure bypass pieces of the oil pump sounds like the pump came apart and then locked up. There should also be either a small steel ball or a steel plunger that is part of this assembly that you need to find. So they don't get picked up again. Also replace the pickup tube and screen assembly especialy if you didn't replace them when you originally rebuilt the engine. They some times they trun loose pieces of carbon that can cause this situation. I would put a new pump in and try your engine and see what happens you have nothing to loose now it will either be alright or it won't at which time you can make a decision as to the fate of the truck. These are tough old motors and will take moe abuse then one can imagaine. Had same issue on a mustang and that motor survived with nothing more done then replacing the Oil pump.

 

Thanks wtroger.

I cleaned the pickup good, it seems clean. I found the plunger, it is still in the pump. I got most of it together and I plan on just slapping it back together to see how bad she runs. Last night I was so upset about the World Trade Center thing, I just ran out and worked on the truck for 4 hours. I needed to get away from everything for a while.

I still have to reconnect the tranny mount, the TB and the intake plenum as well as the exhaust y-pipe. Then I will turn the key and see what happens.

Thanks for the advice.

Randy

 

sounds like you found what locked the pump.

The saafty feature as I understand it cuts of power to fuel pump when no oil pressure however to pressurize system before startup the system does allow a short fuel pump run on key on before startup even without oil pressure thus your restart was likly done via this method and may have been done on zero oil pressure futher damanging the engine with each restart and brief run.

 

I'm going to pass this on, for what it's worth - okay?

I knew a guy named Bob in San Diego that got a REALLY GREAT DEAL on a surfer van...

Read that as a young dumb kid that pieced it together so the chicks would dig it...

It had an I-6 originally, but the kid dropped in a 302. Somehow it ended up with the oil drain plug dead on top of the cross member, where it could not be reached...

The pan therefore, over time, built up so much sludge (because it was never properly drained) that one fine evening it sealed the wire mesh "coarse filter" built into the pick-up tube.

That whole screen was inhaled by the pump - with similar results to what you have already described here. The hexagonal shaft looked like a piece of ornamental wrought-iron, it had twisted several times around until it was too short to reach all the way.

Meanwhile, every bit of the crap in that oil pan would have been distributed to places it should never have gone, if it were not for the oil filter...

There are replacement pickup tubes available. I would take a hard look at the screen on the one you have, and if there is even one failed area - SCRAP IT!

We tend to re-use these parts. They don't come with a long-block.
If it isn't right, get rid of it and buy new.

It's a small secondary defence system PUT there for a reason....

~Greywolf