School a newbie on outboard maintenance

[jyasaki]

Originally Posted by F470

So I need to order a new set of bolts and lock washers for the lower gear case unit. Will 316 or 18-8 from Mcmaster do or do these need to be ordered from a Suzuki Dealer?

Should be fairly standard metric bolts. 316 would be ideal, but expensive, I'd guess. 304 (aka 18/8 or 18/10) would be cheaper, not quite as corrosion resistant, but I think it's the "standard" grade of SS hardware for marine use.

Make sure you use some aluminum rated anti-seize on the threads to prevent dissimilar metal corrosion/bonding.

jky

[F470]

If I wanted to put together metric tool kit to keep in the boat for working on my Suzuki, what tools would you suggest?

[spartacus]

Originally Posted by F470

If I wanted to put together metric tool kit to keep in the boat for working on my Suzuki, what tools would you suggest?

It's not as extensive as you think. Working on an outboard in a pitching sea isn't fun!

Get yourself a 1/2" ratchet drive with sockets from 10mm up, preferably in a plastic case. It needs to include a spark plug socket. A set of philips and flat-head screwdrivers, or one of those tools with interchangeable heads. A decent large over-sized flathead screwdriver is invaluable if you ever have to release the power-trim hydraulics to lift the leg. Set of pliers, needle-nose, etc.

I carry spare outboard fuses, bulbs for console instruments, insulation tape, R pins (cable attachment), stainless steel split pin (propeller), dry rag or kitchen towel (cleaning sparks), and of course spare spark plugs.

[jyasaki]

I'll disagree with Spartacus; You aren't going to be doing massive work on the motor at sea, just a bit of tinkering.

A 3/8" ratchet set will be fine, and by checking all the bolts you can reach, you can probably dispense with 3/4 of the sockets. Screwdrivers, and adjustable wrench, vise grips, prop wrench (assuming you carry a spare prop) and 2 x 4, spare prop nut kit, small hammer (works well on unruly passengers, too) and a small multi-meter. Lots of tape (electrical, duct, and silicone) and zip ties. Some spare electrical wire in case you need to kludge together a circuit or bypass a switch, and some stainless wire (safety wire is ideal (for holding stuff out of the way or wiring things together.) Spare plugs, fuel filter, fuses, fluids (I keep a partial quart of motor oil and a small container of hydraulic fluid for steering.)

In truth, it all depends on a) what you think might happen, b) what you think you can repair at sea, and c) how much room you have to carry all that crap.

jky

[F470]

Thanks for the advice fellas! I've also looked at the "what kit do you bring" thread which I found helpful.

Jumping back and forth here. I dropped the lower unit off at a machine shop today because one bolt broke off and another seized and bent. They're going to charge me $100/hr to extract them which could be up to $300 if the bolts don't cooperate. Seems steep but I know I'll break something if I try to extract them because the bolts that were in there were incredibly seized up. Any thoughts on this? Should I leave it with the pros or should I attempt to extract the bolts myself? Frustrating situation. I'm going to be generous with the anti-seeize on the new bolts.

[F470]

The machine shop is asking if all the holes on my DT-40 lower unit are threaded. Does Anyone know? Also does anyone know why the top right and bottom left holes have a cavity around them?

[captnjack]

I don't know about a Suz specifically, but they are all threaded on every lower unit I've seen. (admittedly only about 6 or 8 total)

I would not use 304 grade stainless, its terrible in salt water. 316 is as good as you can get although the issue (as you have discovered) is dissimilar metal corrosion not corrosion of the bolt itself. The price difference between 304 and 316 is probably less than $1 a bolt.

I would have a machine shop extract them. $100/hr is pretty cheap compared to a new lower unit if you were to crack the casing. If they crack the casing, good luck fighting over who pays for that then...

[F470]

Thanks. I will check what grade I purchased. May have been 18-8. Yes its in a shop and they're $100/hr. They're saying it may take 3-4 hours or more.

On another note. Once they get them out what sealants and lubricants do you recommend when putting it back together. I read the manual and it says to use silicone sealant like Permatex No 2 to create a seal between the lower and upper unit. I'm also confused because they say to lubricate the driveshaft splines with marine grease but they also warn not to grease the top of the driveshaft. Which one is it? What grease is recommended?

[F470]

How about something like this or this?

Originally Posted by jyasaki

I'll disagree with Spartacus; You aren't going to be doing massive work on the motor at sea, just a bit of tinkering.

A 3/8" ratchet set will be fine, and by checking all the bolts you can reach, you can probably dispense with 3/4 of the sockets. Screwdrivers, and adjustable wrench, vise grips, prop wrench (assuming you carry a spare prop) and 2 x 4, spare prop nut kit, small hammer (works well on unruly passengers, too) and a small multi-meter. Lots of tape (electrical, duct, and silicone) and zip ties. Some spare electrical wire in case you need to kludge together a circuit or bypass a switch, and some stainless wire (safety wire is ideal (for holding stuff out of the way or wiring things together.) Spare plugs, fuel filter, fuses, fluids (I keep a partial quart of motor oil and a small container of hydraulic fluid for steering.)

In truth, it all depends on a) what you think might happen, b) what you think you can repair at sea, and c) how much room you have to carry all that crap.

jky

[F470]

Am I ok with 18-8? Thats what all the local places have. 316 would have to be a Mcmaster order and I would have to wait a week. If I am generous with anti-seeize could I get by with 18-8?

Originally Posted by jyasaki

Should be fairly standard metric bolts. 316 would be ideal, but expensive, I'd guess. 304 (aka 18/8 or 18/10) would be cheaper, not quite as corrosion resistant, but I think it's the "standard" grade of SS hardware for marine use.

Make sure you use some aluminum rated anti-seize on the threads to prevent dissimilar metal corrosion/bonding.

jky

[F470]

Good news is they got them out successfully. The bad news is they over charged me. The guy doing the work called when he started and when he finished. 1hr 50min in between the calls. When I get there they charged me for 4 hours = $360. I am going back there now to get a $90 credit but it's still not the $180 they would have charged me for two hours. Sigh.

Originally Posted by captnjack

I don't know about a Suz specifically, but they are all threaded on every lower unit I've seen. (admittedly only about 6 or 8 total)

I would not use 304 grade stainless, its terrible in salt water. 316 is as good as you can get although the issue (as you have discovered) is dissimilar metal corrosion not corrosion of the bolt itself. The price difference between 304 and 316 is probably less than $1 a bolt.

I would have a machine shop extract them. $100/hr is pretty cheap compared to a new lower unit if you were to crack the casing. If they crack the casing, good luck fighting over who pays for that then...

[F470]

I negotiated it down to $210. They tried to pull a fast one. Moving on!

What silicone sealant, gasket sealant and other grease should I use to reassemble the lower unit?

[captnjack]

The drive shaft spines most needing grease are the prop shaft splines!

I'm not sure about the gasket material. That's pretty cheesy of your machine shop...

[F470]

Regular grease? High heat? What about gasket material for the upper/bottom unit seal?

Don't get me started. Very reputable and have been in business since 1927. I'm going to do them a favor and not mention their name. The guy who did the work did great job but the billing dept obviously tried to stiff me. Needless to say I'm not going back there.

[captnjack]

I just use grease from my trailer bearing gun. Its not a high heat area and mostly just to keep the prop splines from seizing. Anything which forms a water barrier until you next change the prop works.

At least on my Yam the powerhead end spines are lightly greased. Not sure why they'd tell you to keep those upper splines bare?

[F470]

This is what the manual says.

[captnjack]

That's what I suspected. Basically a big goop of grease up inside there would push the driveshaft down into the gearcase and force the driveshaft to "flex" since there's no place for the grease in the powerhead hole to go. You don't want the driveshaft to be even 1mm longer due to grease in the powerhead recess so its not greased.

I wouldn't worry about it. If the top splines are wet you have bigger problems than the seizing of the shaft in the powerhead...

The prop shaft splines are most definitely greased.

[jyasaki]

I'd guess any kind of silicone sealant will be fine for the case joint; It's not like you're trying to seal water out of there; the thing gets submerged and has a bunch of holes in it, doesn't it?

For prop, as Jack says, whatever you've got on hand.

To disagree with Jack, I'd say go with the 304/18-8 if that's what you've got. Just make sure you get something to seal the thread recesses (Loctite, anti-seize or grease) so you don't get corrosion in the threads, and figure on changing the bolts every couple of years. It'll still be better than zinc plated or HDG mild steel.

jky

[F470]

Aha. I think I know what's going on here. I removed the lower unit without removing the prop and prop shaft first so the drive shaft is still attached to the lower unit. I noticed some specialty tools are needed to remove the prop and I don't have them. Can I get by with replacing the impeller and seals without disassembling the pop and prop shaft? I understand it needs to be greased but I am a little weary opening that can of worms since I've never done it before and I don't have the right tools. At this point I was just going to replace impeller and seal and reassemble everything then change the lower gear case oil.

Originally Posted by captnjack

That's what I suspected. Basically a big goop of grease up inside there would push the driveshaft down into the gearcase and force the driveshaft to "flex" since there's no place for the grease in the powerhead hole to go. You don't want the driveshaft to be even 1mm longer due to grease in the powerhead recess so its not greased.

I wouldn't worry about it. If the top splines are wet you have bigger problems than the seizing of the shaft in the powerhead...

The prop shaft splines are most definitely greased.

[jyasaki]

[QUOTE=F470;634357]Aha. I think I know what's going on here. I removed the lower unit without removing the prop and prop shaft first so the drive shaft is still attached to the lower unit.{/quote]

Ummm.... Doesn't make a difference.

I noticed some specialty tools are needed to remove the prop and I don't have them.

I use a 6" piece of 2 x 4 (pine, redwood, whatever I can find - used firewood once) and an appropriately sized socket on a breaker bar. Pliers to get the split pin out (may not be needed if you have a tab washer.) That's it.

Can I get by with replacing the impeller and seals without disassembling the pop and prop shaft?

Yup. The impeller sits above the prop and gears, on the (looking at the other way) input to the gearcase.

I understand it needs to be greased but I am a little weary opening that can of worms since I've never done it before and I don't have the right tools. At this point I was just going to replace impeller and seal and reassemble everything then change the lower gear case oil.

Not really that big a deal. Once you drop the LU, you can access the impeller on the top of the part you dropped. The gearcase oil is self contained in the same part (though I've always done that with the LU attached to the rest of the motor.)

If you go on thehulltruth.com and search for "F115 impeller replacement", there used to be a great illustrated guide. Should be roughly the same for your motor.

jky