85HP Force Lower Unit oil

[TexasBayFisher]

I am going fishing this morning and wanted to check the lower unit for the first time, since I just got the boat. So I crawled underneath to remove the hex drain plug and saw that one of the previous owners had stripped it out!
So I decided to remove the vent and fill plugs to at least top up the oil. Nothing came out of either of them. Only after I put a lot of oil in the lower unit did I see what was in there! The oil was BLACK, nasty, and probably 3/4 low. I would guess I added 14-16oz of fluid before it reached the top, then I kept filling it up and flushed out some of the black nasty oil that was in there.

I filled it with Lucas 75w90 full synthetic trans & diff lube.
Does anyone know what the total fill capacity is on this Force 85HP after I'm able to pull the plug and properly drain it?
I saw something about 22oz but am not sure where I saw it.
Also what gear oil is specified?
I believe it's 90w, but manual may not be specific.

I topped it off with what I had- I am going to get some Amsoil lower unit oil but don't have any now so it got the lucas.
I'd like to know if it calls for a GL-4 or GL-5 oil
Reason being GL-4 is safer for yellow metals (brass), GL-5 gear lubes are a little more harsh on yellow metals and cause pitting which reduces life.
Any yellow metals in this lower unit, thrust washers or anything???
I'm new to boats.

Thanks!!
I noticed the engine was a little clanky going into gear when I ran it on the hose today .. I expect that to be gone now that it has good oil and it is FULL.

 

[bradleeson]

Re: 85HP Force Lower Unit oil

Without commenting on any other subjects here, I would be worried that you filled it incorrectly and that you mixed oils.

 

[MWBROWN]

Re: 85HP Force Lower Unit oil

My book said to use EP 90 outboard gear lube. Not automotive type lubricant.

It said not to use automotive type lubricants in three places in the book.

I am uable to locate the amout that the unit holds.

Probably should get some of the correct lower unit oil.

Mike

 

[Frank Acampora]

Re: 85HP Force Lower Unit oil

Capacity: 26 ounces. Marine EP lube in whatever weight ,75-90 85-95 etc. Synthetics are a bit lighter than regular and are about twice the price.

The only "yellow" metal is a bronze sintered bushing in the forward gear and the saddle yoke on the shift shaft. EP5 will not hurt them.

Couple of tricks on the hex set screw: Try putting Ajax sink cleaner in the hole--gives the allen wrench a little more grab. If that doesn't work, try hammering in an old Torx bit. Finally, drill and use a bolt easy-out OR drill oversize and tap for 1/8 NPT plug. (same size as the stainless in the head)

If the lower unit was that low, then very little to no oil was getting to the upper bearing. It is time to pull off the plate under the water pump and visually check the condition of the upper bearing. Note that only the tops of the rollers are visible and to fully check the bearing requires removal of the pinion and shaft. But, at least you can get some idea of its condition without disassembling the lower unit. Turn the shaft by hand while pushing down and see if the bearing is "Grumbling" If so, it is time to replace it. It only came as a very expensive bearing/shaft combo, BUT, the bearing is a standard one and can be bought at bearing supply stores for about 45 bucks.

Note that the plate (and crush washer) holds the bearing by a special addition to the race. Without the plate it is possible to move the shaft up and down a good bit. This is perfectly normal.

Do not try to "get-away" with a marginal bearing. Since the gear load is downward, a marginal bearing will wear quickly. In addition, it will let the pinion pull lower into further engagement with the gears, destroying the whole gear pak. When in doubt, switch it out.

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

Well, I had an interesting boat ride today, to say the least.
Apparently the impeller quit working while underway and the engine over-heated, causing the casing of the orange over-heat wire to partially melt on the cylinder head. I saw a lot of smoke came out from under the cover so naturally I thought it was on fire! I had the fire extinguisher ready to put out the fire as I yanked the cover off while stalled out in the middle of the intra-coastal water way!!!
Luckily someone was kind enough to tow me back! What a mess.

Came home, rinsed off the boat, checked the compression, engine appears to be OK. Filled the cylinders up with ATF and cranked it over a few times and let it sit a while before starting it up, it runs good but there's no water coming out (started for a short time to see if it would run). I was running Amsoil synthetic injector oil (as premix) @ 40:1 when this over-heat happened, and I believe if I had been running regular oil @ 50:1 the engine would have seized. It was HOT.

I found chunks of something similar to steel wool coming out of the top water holes on the rear of the engine. It is definitely metal of some sort. I guess this had to be picked up in the water??
How do I remove this steel wool-like material from the water passages and make sure the water passages are CLEAR??

The lower unit is also dripping oil since I topped it off, but the fill/vent plugs that I previously removed do NOT leak. Also, the fluid is black in color, not gray, so I don't believe there is any water contamination.
How is it possible for the lower unit to leak oil without water getting in??

Do you know where can I get a gasket set to replace the water pump impeller, and carb rebuild kits that contain the proper parts?
Are the Sierra carb kits OK? (just need to stop some float bowl seepage)
I asked about a couple of carb kits that are supposed to work but nobody really said much.


I have a new impeller to install in it. Can I get away with re-using the current gasket with some gasket maker?
The main thing I MUST learn how to do is how to remove that junk from the the water holes. It's really in there, I had to use needle nose pliers to grab hold of it piece by piece and yank it out.

I was excited to be out on the boat fishing for redfish this after noon and all I got were problems.

 

[Matthew A.]

Re: 85HP Force Lower Unit oil

Good to know that there wasn't a fire on your boat.
That steel wool that you mention may well have come from a destroyed impeller housing or worse and not something that was picked up by the water intakes.
L.U.'s with bad seals sometimes leak oil after the oil in the lower unit has increased in temperature. The rise in temperature inside the housing can sometimes create a positive pressure condition inside the housing. As long as the oil isnt allowed to cool off while the L.U. is still sitting in the water, water won't be drawn into the L.U. if a negitive pressure condition inside the housing have been created once the oil cooled.

Since the overtemp alarm wire was melted by excessive engine heat it may very well be that the overheat alarm is faulty.

 

[TWFisher]

Re: 85HP Force Lower Unit oil

Try Munson Marine in South Houston for parts, 713 941 4303. Mon-Sat. They help me with my 89, 85hp. They know Force. Ask for April, let her know what you need and she'll be determined to find it. They can ship the parts to you.

Let us know what you find out about the metal material, Ive never heard of that before.

While you have it all apart, you may want to read the sticky about adding a tell-tail. It may have helped you to catch the water pump problem a little earlier.

This sounds alot like my typical boat outings....

 

[Frank Acampora]

Re: 85HP Force Lower Unit oil

Dripping from where? there are a couple of vent holes under the cavitation plate to drain water from blind chambers. Engine oil and black crud will drain from these holes. It is not from the lower unit unless the shift rod seal is leaking and oil forces its way through it then vents through these holes. If the drive shaft seal was leaking, the oil would pass out with the water AND the water pump would force water into the lower unit.

To get the steel out, try pushing back the idle relief bellows. If that doesn't give you enough room, then remove the rear shroud. Six bolts outside and six or eight--I forget-- inside around the lower pan. There are two roll pins on the bottom of the rear shroud and you must pry it off.

If you replace the impeller, before you replace the lower unit, remove the thermostat housing and the thermostat and blow water through the hole. Then, after replacing the lower unit take it to the water. With the thermostat and cover still off, run it at high idle or even in gear for a couple of seconds to get the rpm up to 2500-3000. That new impeller will force anything out the thermostat hole way better than you could do on muffs. If you still suspect clogging, then you have no choice but to remove the head and exhaust cover and manually clean the water passages.

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

You're right Frank, it came out of the weep holes.
In fact I unscrewed the vent plug today after it had been sitting and air blew out of the lower unit, followed by some gear oil. To the best of my knowledge it is not leaking, so I'm happy about that.

I'm changing the impeller tomorrow morning, I will report back with how badly damaged the old one is. Will be sure to remove the thermostat and flush out the cooling system as you suggest.

Guess I should test the thermostat while I have it removed, right?

Thanks!

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

About to get started

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

I removed the lower unit and replaced the water pump impeller, the old one had all of its tips completely worn off. I thoroughly cleaned the pump housing and reconditioned it the best I could, it had some bad pitting but it will work 'OK until I order a new one. Reinstalled the cleaned housing with lots of palmolive dish soap.
I flushed the water tube and cleaned out the "idle relief bellows" tube between the engine and the rear water holes.
Your instructions were very good, thanks. It was simple and straight forward once I got into it but it was comforting to have a guide having never torn into an outboard.
I removed the thermostat housing and took out the thermostat and flushed it all out, good clean water flow throughout. Just to be sure the thermostat was good I tested it, threw it into some boiling hot water and it is BAD.
So not only was the impeller chewed up, the thermostat was the real show stopper!

Reassembled without the stat using a little bit of RTV on original gasket, no leaks.
Started it i[ and have good water flow, unfortunately the water is also flowing out of the head gasket!

At minimum it has a bad head gasket. Possibly a warped head.
What are the chances of the BLOCK itself warping from an over-heat??

Should I replace the head gasket and see if all is good, or should I have the cylinder head looked at by a machine shop?
How about the block?

PS. Where do I buy the replacement water pump housing?
Found a kit on ebay, but I would like to buy it from iboats

 

[Frank Acampora]

Re: 85HP Force Lower Unit oil

The block is usually too massive to warp. The head, however, can warp. Put it on a flat pane of glass to check. Manual says you can take off .010 to true it but I have gone .060. Careful, .060 increases the compression ratio and may cause detonation. If she pings, reduce timing a couple of degrees and go to higher octane fuel.

More than likely though, the head gasket was ruined. If it is still holding compression, Permatex on the fiber portions may stop the water leaks.

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

Got a good used cylinder head on the way to me, along with a new gasket.
New thermostat also.

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

Can you tell me what the torque value is for the head bolts?
Also, how about using a little bit of Permatex Ultra Copper on the new gasket?

 

[Frank Acampora]

Re: 85HP Force Lower Unit oil

Head gasket goes on dry. NEVER use anything with copper or graphite on an outboard--Galvanic corrosion. 225 INCH pounds torque. Start at about 150 on all bolts then go to 225 in two steps. Run engine to heat it then re-torque to 225 inch pounds after it cools.
Start from the center two bolts and spiral outward to prevent warping the head while torquing.

Head bolts are supposed to go in dry also but I like to use permatex silver color anti-seize. I think it is nickel based. Even lubricated with the anti-seize, they will not strip at 225 inch pounds.

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

Thanks Frank.
I was expecting a bit higher torque spec.
Can you tell me the torque spec on the lower unit bolts, and pump housing bolts?

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

By the way, I picked up a water pump kit.
Came with new housing, gaskets, new impeller, plastic pieces, and bolts.
Exactly like this one:
Force 85HP water pump kit


I will install the kit, new thermostat, and the used head I picked up w/new gasket.
Hopefully this fixes it.
I'd like to learn the torque specs on the lower unit and pump housing bolts, as I have a bad habit of over-tightening fasteners in aluminum.

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

Is there a manual I can buy with torque specs?
I bought one on CD but it doesn't list any specs.

I'm going to remove the lower unit this morning to install the water pump kit.
Torque specs would be GREAT if you've got them handy or memorized.

 

[sailingwest]

Re: 85HP Force Lower Unit oil

Hi Tex , Seloc online as the name suggests do online manuals that I personally find first class you will find all the info you need in them and you can print out the info you need and take it to the boat with you. Jim B

 

[TexasBayFisher]

Re: 85HP Force Lower Unit oil

Thanks, Jim!