Removing oil pan help

[spoulson]

I'm digging into the engine to replace the oil pump after seeing my pressure dropping.

So, following tips from the Haynes manual and whatever else I've read, I jacked up the engine close to a foot. I was able to stick a short 2x4 block under the engine mounts to hold it up. The oil pan is unbolted and dropped.

But, how in the hell does it come out? There's not enough clearance front or back to pull it out. I can't jack up the engine much more because the intake is nearly touching the firewall and some wiring is getting tight.

What could I be doing to make this procedure easier?

 

[68stang351]

You should be able to just barely fish it out. I did it basically the same way on my 90 ( I had a engine hoist holding the engine up) and I was able to get it out. I think I was using a short 1/4 drive socket to get to it but I can't remember.

It is possible to change it in car though. It wasn't fun, but it's been done.

 

[faststang90]

we did it years ago big pain in the @@@. i think we backed off the tranny mount bolts to it would give us alittle more room.

 

[stykthyn]

just pull the whole motor. its a whole lot easier that way and you can clean things up while the motor is out. I am looking at having to do this exact thing very soon.

 

[rpk]

I undid the oil pump while pan was resting on the rack,then it gives you more room to tilt pan and fish it out

 

[jrichker]

86-93 5..0 Mustang oil pan gasket and oil pump removal & replacement

Been there, done that - You can do it in the car, but it is hard to do. The best way is to pull the engine.

Disconnect the battery at the battery ground terminal, remove the fan and fan shroud. Both motor mounts will need to have the large nuts that secure them to the frame removed. The trans mount will also have to be loosened, and it is a good idea to remove the drive shaft.

The rear driveshaft bolts are 12 MM, 12 point, and require a first class box end wrench (ring spanner if you are English or Canadian) to remove them. Don't get cheap here or you will regret it. I set the emergency brake and apply a foot to the wrench to loosen the bolts. Notice the paint marks on the driveshaft & rear end flange: align them the same way they came off. If there aren't any marks, get out your paint spray can & make your own marks. Have a catch pan in place to get the fluid that comes out of the trans when you pull the driveshaft yoke out.

I also had to disconnect the cat pipes at the headers to get the engine high enough to remove the oil pan. Be prepared to have to drop the steering rack and disconnect the steering shaft. The flex coupling for the steering shaft needs to be disconnected before you can get the rack out. You should disassemble the coupling by removing the 2 bolts that hold it together. Jack up the engine with a wood block under the oil pan and watch for things that bind or hoses/electrical wiring that may need to be disconnected. I put a couple of wood blocks between the headers and the frame to support the engine. You will likely need to jack up the rear of the transmission as well to get the required clearance.

Scrape the pan mating surfaces clean as possible - old gasket stuck to the surfaces are a source of leaks.

Get a high volume/heavy duty pump, and a replacement HD pump shaft. FMS makes one, and ARP does too. When you install the pump, the funny looking washer thingy goes on the part of the shaft that fits into the hex socket in the distributor shaft. It keeps the shaft in place when you remove the distributor, which you will have to do to prime the pump. Forget to put it on, and the pump shaft can come loose and fall down in the bottom of the oil pan.

There is a one piece oil pan gasket which will help re-assembly if you can find it. If you can't get this gasket, use weather strip adhesive to secure the cork gasket to the pan rails and the rubber strips to the bearing caps. Use lots of Acetone or MEK to clean the gasket surfaces so the weather strip adhesive will stick good. Read the instructions on the adhesive carefully to make sure the gaskets are permanently stuck in place and won't move when you slide the pan in place. Use lots of blue silicone sealer on top of the front and rear rubber seals where they mate with the pan.

Fill with oil, replace the filter. Reconnect the battery, switch the ignition on to enable the gages,
but DON'T crank the car. Remove the distributor and use a 1/4" hex socket to turn the pump counter clockwise (same direction as distributor rotation) until you see oil pressure (an external gage is a great help long about now). And keep turning for about 30 sec after you see the pressure come up. A reversible drill is the best tool to use to turn the 1/4" socket. The pressure should come up to about 50-80psi with cold oil. Once you see good pressure, check for obvious leaks, and then and only then, lower everything back into place and bolt down the mounts and anything else you had to take loose.

Putting the distributor back in is fairly simple. Pull #1 sparkplug, put your finger in the sparkplug hole,
crank the engine until you feel compression. Then line up the TDC mark on the balancer with the pointer on the engine block. The distributor starts out with the #1 plug wire lined up at about 12:00 with you facing it. Align the rotor to about 11:00, since it will turn clockwise as it slides into place.
Align the distributor rotor up with the #1 position marked on the cap, slide the distributor down into the block, (you may have to wiggle the rotor slightly to get the gear to engage) and then note where the rotor is pointing. If it still lines up with #1 position on the cap, install the clamp and bolt. If not, pull it out and turn 1 tooth forwards or backwards and try again. Put the #1 spark plug back in and tighten it down, put the clamp on the distributor, but don't tighten it too much, as you will have to move the distributor to set the timing. Note that if it doesn't align perfectly with #1 position, you can turn the distributor until it does. The only problem is that if you are too far one way or the other, you can't turn the distributor enough to get the 10-14 degree optimum timing range.

Set the timing with the engine running using timing light (don't forget to disconnect
the SPOUT plug and reconnect it when finished) 12-14 degrees BDC is good. Start up and check for leaks, let it warm up and look again for leaks. It took me 2 days plus, but I am old and slow, maybe your granny is faster.

 

[spoulson]

Wow, that is a very detailed writeup. Thanks!

On the topic of high volume pump, I went with a standard volume Melling pump. Sounds like some have had issues with a high volume draining a stock oil pan and starving the engine at times.

I think I would be happier with pulling the engine in a hoist. Where is the best place to attach to when pulling it straight up?

 

[doorvip]

I'm having the same problem with pressure dropping. I have a reman 306 with new oil pump, I think its somthing more in my case?

 

[jrichker]

Wow, that is a very detailed writeup. Thanks!

On the topic of high volume pump, I went with a standard volume Melling pump. Sounds like some have had issues with a high volume draining a stock oil pan and starving the engine at times.

Thanks to Stangnet member bubba-dough for helping to educate all of us...

http://data.melling.com/Tech pdfs/HIGHVOLUMEPUMPS.pdf
You will need the Adobe Acrobat viewer which is also a free download – Adobe - Adobe Reader download - All versions

From the Melling site, for those who didn't follow the link & read the tech note...

View attachment 240382

High Volume Pumps: Advantages, Myths & Fables

Most of the stock automobile engines are designed to operate from idle to 4500 RPM. The original volume and pressure oil pump will work fine in this type of application. As the demands on the engine increase so does the demands on the oiling system and pump.

The oil pump's most difficult task is to supply oil to the connecting rod bearing that is the farthest from the pump. To reach this bearing, the oil travels from three to four feet, turns numerous square corners thru small holes in the crankshaft to the rod bearing. The rod bearing doesn't help matters. It is traveling in a circle which means centrifugal force is pulling the oil out of the bearing.

A 350 Chevy has a 3.4811 stroke and a 2.111 rod journal. The outer edge of the journal travels 17.5311 every revolution. At 1000 RPM, the outer edge is traveling at 16.6 MPH and 74.7 MPH at 4500 RPM. If we take this engine to 6500 the outer edge is up to 107.9 and at 8500 it is 141.1 MPH. Now imagine driving a car around a curve at those speeds and you can feel the centrifugal force. Now imagine doing it around a circle with a 5.581, diameter.

The size of the gears or rotors determines the amount of oil a pump can move at any given RPM. Resistance to this movement creates the pressure. If a pump is not large enough to meet the demands of the engine, there will not be any pressure. Or if the demands of the engine are increased beyond the pumps capabilities there will be a loss of oil pressure. This is where high volume pumps come in; they take care of any increased demands of the engine.

Increases in the engine's oil requirements come from higher RPM, being able to rev faster, increased bearing clearances, remote oil cooler and/or filter and any combination of these. Most high volume pumps also have a increase in pressure to help get the oil out to the bearings faster.

That is what a high volume pump will do. Now let Is consider what it will not do.


It will not replace a rebuild in a worn-out engine. It may increase pressure but the engine is still worn-out.

It will not pump the oil pan dry. Both solid and hydraulic lifters have metering valves to limit flow of the oil to the top of the engine. If a pan is pumped dry, it is because the holes that drain oil back to the pan are plugged. If the high volume pump is also higher pressure, there will be a slight increase in flow to the top.

It will not wear out distributor gears. The load on the gear is directly related to the resistance to flow. Oil pressure is the measure of resistance to flow. The Ford 427 FE "side oiler" used a pump with relief valve set at 125 psi and it used a standard distributor gear. Distributor gear failures are usually caused by a worn gear on a new cam gear and/or worn bearings allowing misalignment.

It will not cause foaming of the oil. With any oil pump, the excess oil not needed by the engine is recirculated within the pump. Any additional foaming is usually created by revving the engine higher. The oil thrown from the rod bearings is going faster and causes the foaming. This is why high performance engines use a windage tray.

It will not cause spark scatter. Because of the pump pressure there is a load on the distributor gear. The number of teeth on the oil pump gears determine the number of impulses per revolution of the pump. In a SB Chevy there are seven teeth on each gear giving 14 impulses per revolution. At 6000 RPM the oil pump is turning 3000 RPM or 50 revolutions per second. To have an effect on the distributor, these impulses would have to vibrate the distributor gear through an intermediate shaft that has loose connections at both ends. Spark scatter is usually caused by weak springs in the points or dust inside the distributor cap.

High volume pumps can be a big advantage if used where needed. If installed in an engine that does not need the additional volume, they will not create a problem. The additional flow will be recirculated within the pump.

 

[2000xp8]

I think you are just wasting your time and money replacing the oil pump, dropping oil pressure is rarely the pump itself.
More like bearing.
This coming from someone that has worn out their share of engines, all of which were connected to an autometer mechancial oil pressure gauge.

If you do replace the pump, just pull the engine.

 

[spoulson]

I'll find out for sure if the pump was really the root cause later tonight when the oil pan gasket comes in at NAPA. FYI, this post details my oil pressure symptoms before deciding to replace the oil pump.

If I may say, I'm glad I switched to a Mustang as a project car because parts are pretty easy to find and there's lots of enthusiasts in every corner. There's also no shortage of conflicting information. It's the bearings, it's not the bearings. It's the spring in the pump. High volume is going to drain your pan, increase oil pressure, divide by zero. Standard volume isn't enough for a performance engine. I'm wasting my money, buying the wrong parts. I certainly appreciate everyone's input, but it can be hard to make the truth out of all this stuff.

Well anyway, I thought I ordered a standard volume, but the stamping on it is Melling M86HV. The one I took out looks identical but has M86, no HV. No big deal after reading jrichker's Melling post.

 

[2000xp8]

I'll find out for sure if the pump was really the root cause later tonight when the oil pan gasket comes in at NAPA. FYI, this post details my oil pressure symptoms before deciding to replace the oil pump.

After reading your post on the other forum, put an autometer mechanical gauge inside the car, permanently so you can see what's going on all the time.

You say it has 20psi at warm idle, that's not bad at all. I've driven engines down to the point where they were getting under 10psi at idle.

 

[spoulson]

You say it has 20psi at warm idle, that's not bad at all. I've driven engines down to the point where they were getting under 10psi at idle.

You're missing the point in the explanation. The oil pressure wanders between low to normal both at idle and cruising. At one point the needle on the stock gauge dipped to just above the red for a little while while cruising at highway speeds ~2.5k rpm, and then wandered back up. I'm guessing that's below 20psi. When I revved it the pressure did not increase. The mechanical gauge verified the wandering pressure at idle. In fact, my symptom matches reason #2 in this post for a failing oil pump.

 

[doorvip]

I pulled the oil pan off my engine, need a crank kit. bearings went bad, but didnt spin and the crank looks like ****. thats 400 miles on a reman 306, wish it was the pump.

 

[spoulson]

For the archives, I was able to complete the oil pump job with only dropping the oil pan against the crossmember. Jacking up the engine and lowering the steering rack was enough room to drop the stock pan. There's enough room to get the two pump bolts and pickup mounting nut, if you don't mind feeling like you did about 1000 crunches by the time it's done.

Also, I went with a FelPro rubber oil pan gasket. It was definitely worth the $28 paid at NAPA. Never before have I seen these plastic gasket holder pieces that screw in the oil pan bolt holes to hold up the gasket. The other end of the piece is a snap that lets you push the oil pan through it and snap into place so you can be sure the gasket is lined up and the oil pan is held up while you're putting the bolts in.