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OMC 43L 1989 Stern Drive Oil Fill Screw Stuck

D

dougbreault

Contributing Member
"Hello,

The oil fill screw

"Hello,

The oil fill screw on the right side of the stern drive, a little more than half way down, is not budging. I sprayed two shots of PB-blaster on it, with no luck. I bought a bigger screw driver that fits the slot pretty well, and at least it's not trying to strip now, but it won't move.

Is it time to torch it?

If so, what do you train the torch on, the screw head or the area on the drive around the screw head?

How long do you hold the torch to it?

Do you need to worry about any remaining oil in the drive catching fire or blowing up? (I've drained whatever could be drained from the bottom drain plug with the oil-check screw at the top of the drive out. )

Thanks,
Doug"
 
"All the oil should be out by

"All the oil should be out by draining from the very bottom screw but I would be very leary about torching it. If your screwdriver is a good fit for the slot, give it a couple of shots straight on with a hammer, I've even used a square shank screwdriver so I could put a wrench on it. Worse case try filling it from the bottom, if the oil comes out the top and it takes the 64 oz then I would say you've filled both the upper and lower."
 
"Guys,

I picked up a new im

"Guys,

I picked up a new impact driver, held it on the screw and whacked it about 30 times and it did not budge so much as a millimeter. What do you recommend from here? I sprayed some more PB Blaster on it last night after retreating from the hammering.

Dumb question but is there any trick to holding the impact driver? I was holding it tight around the chrome knurled end... there's also an additional chrome knurled ring towards the bottom of the main chrome handle... should that part be in my grip or not? All I could think was maybe I wasn't holding it right or something but it seemed straight forward.

Thanks for any and all suggestions. The water temp is 54 degrees here, stripers are in and I'm monkeying with a stuck screw...


Thanks,
Doug"
 
"hm, I didn't do anything

"hm, I didn't do anything to the ring itself. I tried twisting it either way but it didn't budge. I did do the counter rotation of the point and the handle, to set it to the R or L position. If say I push it into a piece of wood, the screw bit turns counter clockwise, that's what I want, right?

I am curious about that ring though. There was no manual with the driver, except for a small badly written piece of paper with incomplete info.

Here's the one I bought from Performance Tool.

http://www.tooldiscounter.com/ItemDisplay.cfm?lookup=WLMW2500P&source=froogle&kw =WLMW2500P

Looks (to me) like a quality unit but the instructions were bad and lacking.

Doug"
 
"I think you are using it righ

"I think you are using it right but maybe you need a BFH!

Impact Driver
The best remedy for a stuck screw, or one whose head has been stripped, is the impact screwdriver. An impact screwdriver is essentially two weights held apart by a spring. The bottom one holds screwdriver bits. You smack the top one with a hammer. In between them is a spring and a circular ramp. The ramp makes the bottom weight with the bit in it turn. So when you hit the top weight, giving it momentum, it compresses the spring and hits the ramp which turns the screwdriver-bit-holding bottom weight. The beauty of the design is that the force you impart to the impact wrench by hitting it with the hammer is forced into the screw, helping the screwdriver bit bite into the screw head (or what's left of it). Most impact drivers will let you set them for left and right turning, to loosen or tighten screws.

The high-quality, hardened screwdriver bits that come with impact drivers usually fit the screw heads much better than even the best screwdrivers, which helps all by itself. So at the first sign of a recalcitrant Phillips head screw, reach for the impact driver! Impact drivers are commonly available and cost about 15 (American) dollars - check your local auto supply store.

Some cheap impact drivers have (relatively) stiff springs which require a heavy hammer to compress and get the ramps to turn the bit. Be warned that the force needed may be damaging to the assembly in which the screw is stuck, or may be difficult to counteract on an awkward piece. These impact drivers can benefit from being disassembled and having the springs shortened slightly (no more than 25 percent) to reduce the spring preload. After this modification the driver will not require as much force but may not work quite as well on really badly buggered screws."
 
"Get a torch and heat the scre

"Get a torch and heat the screw till nice and hot, not melting, and then smack it with the impact. Just did a Volvo yesterday with the same problem"
 
"Thanks. I tried that a few ti

"Thanks. I tried that a few times yesterday, no luck. I will keep trying.

A few questions,

1. One thing that's always had me baffled was why do you fill the oil in from the middle fill hole, when there's a fill hole up top higher than it? Considering gravity, how does the oil ever get up to the dip stick on top of the stern drive, if you fill it from a foot below it?

2. If I never get that screw off, can I just fill the oil from the dipstick hole on top?

3. Someone mentioned filling in the oil from the bottom hole. That seems even more contrary to the laws of gravity than filling from the middle oil fill hole.

What am I missing here?"
 
You do not fill from the middl

You do not fill from the middle hole.
You fill from the bottom until oil comes out of middel. Then close middel and fill until mark at dipstick.
Due to design of lower unit there will be a huge air-pocket if middle is not out when filling.
 
"Doug.....if you filled from t

"Doug.....if you filled from the top with the bottom and middle screws in, where would the air go that's displaced by the lube? you fill from the bottom and middle (in a perfect world)using a small hand pump that attaches to the bottle of lube. As you pump it in you are forcing the lube upwards which literally pushes the air out the top dipstick hole. As I mentioned before if you can't get the middle out, I would still try to fill from the bottom, those drives hold 64 oz and if it takes it all I still think you'll be ok but if there is some left then you have an air pocket and Murphy's law says it will work it way to those upper gears sometime and then you'll have real problems.

The correct procedure is to fill from the bottom until it comes out the middle, put the bottom screw in and continue filling from the middle until it reads a little above the line on the dipstick with the dipstick just resting in the hole. Then you screw in the dipstick and the middle screw. Run it a bit if you can, let it sit overnight and check the dipstick again."
 
"Ah, a hand pump. That's t

"Ah, a hand pump. That's the part I was missing. I get the bit about the air displacement. I'll have to find one of those pumps.

What would happen if you carefully trickled slowly a couple oz's of lube in from the top hole over a longer period of time, such that the diameter of the lube stream wasn't completely filling the fill channels? Really bad idea due to chances of still having air pockets?

I'm guessing that if you filled from the bottom hole with the pump, the pump must completely block the hole on the bottom, otherwise the lube would just immediately spill right back out the bottom hole, right?"
 
"Hi Doug, the hand pump is sma

"Hi Doug, the hand pump is small, it screws right on top of the quart of gear oil and the end of the tube screws into the drain hole. I seen them at wal-mart in the boat section. Here is one here.

http://www.dougrussell.com/Products/index.cfm?fuseaction=ProductDetails&ProductI D=136&Category=7&Brand=126

Any boat dealer should have one. The oil is thick, when you fill from the bottom screw and it runs out the middle screw hole, take out the pump hose, not even a spoon full will run out by the time you get the drain screw back in. Then do the same with the middle plug. If you don't it is like they said, air gets in there and when you later go out on the lake and run it, the oil level will drop as the air rises and the top gears will run dry delomish thereselves."
 
"Guys,

After a lot of heat

"Guys,

After a lot of heating, PB Blaster, and banging with the hand impact driver, the screw finally budged a little while ago and moved about 5 degrees. Now it's being stubborn again.

So far the slot is still pretty much in tact on the screw but it's widening a bit. Any suggestions where I can buy a replacement screw if this one gets totalled and if I get it out? I checked the OMC section on this site and could not find a subsection for outdrive screws.

Also, bought a drill pump that looks like it was meant to pump water (two garden hose attachments on the in and out ports... but the darn thing doesn't want to suck oil out of the dipstick tube. It's got a rubber tube that's down in there. What a pain in the neck, I can't get it to work at all. Really bad day working on the boat... except for the 5 degree movement on that screw."
 
"The screw finally came out! A

"The screw finally came out! After lots of heating with torch, hammering with the impact driver, and PB Blaster, the thing finally came out on Sunday night. Thanks to everyone for your help.

Also, I may have originally been using the impact driver incorrectly, not sure. I wasn't sure whether you should hold it tight into the direction you want it to turn or a little looser. When I held it tight in the direction of the turn, it seemed to torque it better. It's hard to explain, and probably harder for you mechically inclined guys to imagine, but I thought maybe the quick turning action of the screw needed a little bit of looseness to generate some momentum before really impacting the side of the slot. Didn't work so well though, and once I started holding it really tight into the turn, it started to budge. Not entirely sure if it was that or the heat or the PB Blaster or just time that did it.

Anyway, it's out, and I need that replacement screw. Thanks for the link to the screw Bob.

Also, as for the engine oil... a new hand pump and drill pump later, I decided to just make a small oil pan with a tube in the bottom of it, run out the transome hole, to drain the oil. Hoping the drain plug is on the bottom of the engine. Sucking the oil out of the dip stick went horribly for me. Hoping this other method works.

Thanks again for help as always."
 
"Glad to hear you got it out D

"Glad to hear you got it out Doug, I guess lots of perserverance and patience paid off for you! Not sure if your idea with the oil drain will work though, a lot of these pans don't even have a drain screw, instead there is usually an adapter fitted in and then that becomes the dipstick tube. See pic below

80859.gif


Not sure if used the thin tube that goes all the way down inside the dipstick tube or the kind that attaches to the top with a garden hose fitting? The key thing is to run the engine first to really warm up the oil plus it gets the crap suspended in the oil to get sucked out as well."
 
"Oh damn it all, I think my en

"Oh damn it all, I think my engine has that!

I was using the tube that goes into the dipstick hole... worked horribly both by hand and by the drill pump."
 
"Yep that pic is for a 1989 4.

"Yep that pic is for a 1989 4.3 pan, but you should have the garden hose fitting at the top of the tube, comes out much better than the little tube, might as well try to suck it out with a straw
happy.gif
"
 
"Bob, you are right of course,

"Bob, you are right of course, I just didn't notice that garden hose fitting. I checked for the fitting last night and it was there. Got the oil out with the drill pump. Now engine oil and stern drive lube are all good to go. Started up great, prop still turning miraculously after the stern drive removal and reinstall.

Going to check the fluid levels again tonight, get new tires for the trailer (wheels are all rusted and the tires are pretty beat up), and do final checkout of entire boat, and we should be in the water this weekend.

Thanks for your and other's help!"
 
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