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787 Engine Teardown

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I don't doubt it's a no brainer to an experienced wrencher like you, but to me taking out a warranteed engine and putting back in the replacement, even if I can be back here in two or three hours with it isn't something I would look forward to ... well, you see how long it took me to just take the top off this engine. I like the warranty I got with my Trane AC ... when it failed they came out, pulled the leaking unit, installed the new one, charged it with Freon, tested it and I didn't even need to put down my drink. :-) But then, I'm not paying 5 grand for a pwc rebuilt.

The no fault warranty is about the same from SBT and SES, but SES uses more OEM parts or so they claim, so I don't care as much about the warranty compared to how much I care about the chances of the engine not needing the warranty in the first place, which the consensus around here seems to be, that OEM parts last longer.

At any rate, I'm not anti SBT. Maybe before school starts I'll take my daughter over to Busch Gardens in Tampa and swing by SBT either going or coming. I'm sure she'll be thrilled to see a noisy, oily machine shop. :-)

Its actually a pretty cool tour, two rules to remember, no open toed shoes (sparks), and no lunchtime tours.
 
Its actually a pretty cool tour, two rules to remember, no open toed shoes (sparks), and no lunchtime tours.

Sounds good, I'll have to see if I still have shoes with closed toes. Shorts, t-shirt and flip flops have been my standard garb in FL for so long I forgot how to tie shoe laces.

However, I think I might be ready for a straight jacket fighting this SeaDoo teardown. I got the remaining 3 RV cover bolts loosened, but they were so packed with corrosion one cracked and took the corner of the bolt hole in the cover off as it was coming out. Since it's just a through hole, maybe that corner can be welded back if it's even needed. 90% of it is still there.

The bigger issue at the moment is that even with 3 of the bolts out, and the one broken stud has no head, the cover just won't budge off.... or even move enough to get something between it and the case. I almost have to wonder if BRP has a special corroded on RV cover removal tool.

RV cover broken bolt casting.jpg
 
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The bolt that is broken...do you have any part of it sticking out? I would use some heat and channel locks or small pipe wrench. Heat does amazing things just be careful not to destroy something around it. Use sheet metal shielding for surrounding components.

You can use 243 thread locker where you see the yellow stuff.
 
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The bolt that is broken...do you have any part of it sticking out? I would use some heat and channel locks or small pipe wrench. Heat does amazing things just be careful not to destroy something around it. Use sheet metal shielding for surrounding components.

You can use 243 thread locker where you see the yellow stuff.

Yes, part of the broken bolt would be sticking out of the block if and when I can get the RV cover off to expose the part that sticks out. The bolt was sheared right under the head. Unfortunately, the RV cover does not want to budge despite various increasing levels of encouragement with a rubber mallet, wood block and hammer, heat gun ... cursing ...
 
hmmm... after stealing your wall ratchet idea, I might have to steal this idea as well. It will come in handy a couple times a year, especially with the 951's, I don't find the 787's and smaller SD's to be much of a problem.

Here's another idea you can steal if you like. It's my new very special tool pump housing puller. (pat pending) Works like a charm. Took half a minute and no cranking on bolts. Even has vinyl coated hooks to protect the nozzle vane. Whole thing popped right out shaft and bilge pump lines and all.

Pump Puller Special Tool A.jpg

Pump Puller Special Tool B.jpg

Pump Puller Tool c.jpg

After pulling the pump and drive shaft, I discovered the carbon seal was running a tad off center. Is this normal since the bellows holding the seal is only as true as the layup surface on the thruhull? Anything to worry about? I plan to install a new seal.

[EDIT] Sorry, I take that back, after removing the bellows I see there is a plastic collar thru hull piece that locates the rear of the bellows. Took the front bellows off and can't figure out what the zerk fitting is for on the PTO flywheel hub. I thought there was a bearing in there but I don't see one. Is it just to keep grease on the spines? I can't believe I've been greasing it after every ride just for that purpose. The impeller end has no grease fitting although it does have a seal of sorts. I would think that end would be the one to rust up.

carbon seal a.jpg

carbon seal b.jpg

carbon seal c.jpg

This is the lower starboard magneto cover bolt that sits right behind the front motor mount. It is not possible to get any wrench I own on that bolt and having any leverage unless the front of the engine is raised about 6" after removing the drive shaft and loosening the rear mounts. Why am I trying to take off the Mag cover in the boat? So that it's held by its mounts when I torque off the PTO flywheel and the mag flywheel nut. It might also be something worth knowing how to do on a 787 in a 98 spx if you just want to check or change the trigger coil or stator without pulling the engine. Although now that I have all the bolts out finally, does the cover want to come off? No it does not. boohoo.

Mag cover bottom bolt.jpg
 
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Hey my special tools from SBT just arrived! Let the games begin.

Just downloaded Tapatalk.... Easy to use on a phone.


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Yay, some tools just arrived from SBT so hopefully I can get The flywheels off!

Oops sorry for the repeat msg. Got an error msg the other one didn't post. Forgive a Tapatalk new user.


Sent from my iPhone using Tapatalk
 
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I've got the rope between the top of the PTO piston and the head, special tool in the splines of the PTO flywheel, a hardened impact socket on the special tool, a 24" breaker bar, and a 4 foot 1/4" wall tube over the breaker bar turning counterclockwise looking from the back, it won't let loose. I've got so much leverage on it the whole SeaDoo is lifting off the trailer. I strapped it down to the trailer and can tip the whole thing trailer and all but the PTO flywheel still won't budge. Any ideas?

I've tried heating the flywheel with butane. Also tried an impact wrench but the rope just compresses.

PTO flywheel removal.jpg
 
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Constant pressure and gold it there at full pull and it should pop. Could be rusty

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Constant pressure and gold it there at full pull and it should pop. Could be rusty

Thanks, I rigged up a strap around a power pole to put constant pull on the pry bar. I ratcheted in the straps until the SeaDoo came off the trailer on the starboard side. I stepped on the high side to bring it down but it barely moved and I weight 190. The starboard rear motor mount looks like it's stretched almost to its limit and I don't want to destroy it. I'm leaving it like this for a while ... been a few hours so far. My guess is there's ~ 800 ft-lbs of torque on that flywheel. My neighbors are starting to wonder why I'm trying to pull over the power pole with a SeaDoo.
PTO removal off the traile.jpg

PTO removal off the trailer.jpg

PTO removal engine mount stretched.jpg

PTO removal pull fixture.jpg
 
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Well, not quite what I meant. I mean you keep steady pressure on it. They don't like it when you creep up on them, like I quick snap of the wrench. I use either a breaker bar or a 1/2" ratchet. Then instead of flimsy box tubing like you have I use 1.5" black iron 1/4" wall pipe from Home depot. I bought a 3' scrap one day. That pipe doesn't flex like box tubing will. If I can't get it with the breaker and cheater I switch to the ratchet to get a better pull. Notoriously they PTO is never in the "sweet spot" to get the desired swing, but you can tweak that with the ratchet. I also don't care if I blow out the ratchet, sears has one waiting for me 7 days a week.
 
as racerxxx said give it a quick snap which would give a much better chance of breaking it loose. pretty much the same effect as an impact wrench would have.
 
Well, not quite what I meant. I mean you keep steady pressure on it. They don't like it when you creep up on them, like I quick snap of the wrench. I use either a breaker bar or a 1/2" ratchet. Then instead of flimsy box tubing like you have I use 1.5" black iron 1/4" wall pipe from Home depot. I bought a 3' scrap one day. That pipe doesn't flex like box tubing will. If I can't get it with the breaker and cheater I switch to the ratchet to get a better pull. Notoriously they PTO is never in the "sweet spot" to get the desired swing, but you can tweak that with the ratchet. I also don't care if I blow out the ratchet, sears has one waiting for me 7 days a week.

How true, I was running out of swing room so got out the 1/2" ratchet to get a better reach and at one point I had so much pressure on it, it snapped a pawl. Brought it back to Sears and they even had a reconditioned one waiting under the counter at the cash register! I commented that they must replace these often if they keep them at the cash register. He said, "Oh yeah, couple a week. People put longer pipe handles on them and use them as breaker bars."

The aluminum is T6 1/4" wall structural tubing left over material from the aluminum boat lift that's holding up my 4,700 pound boat/motor across an 8' span with no noticeable flex, but I'll take your advice and pick up some 1-1/2" 1/4 wall black iron pipe at HD today.

[EDIT] Something I noticed yesterday is that the rope I'm using seems to compress some under the pressure making it hard to "snap the wrench" ... while I'm picking up the pipe I'll look for a harder rope. I wonder is a soft piece of pine disk the diameter of the piston under the head would help ... or hurt something.
 
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as racerxxx said give it a quick snap which would give a much better chance of breaking it loose. pretty much the same effect as an impact wrench would have.

While I had all that pressure on it, I hit the pipe with a sledge hammer a few times. The PTO just laughed at me while the motor mount groaned in pain.
 
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All the Home Depots within 25 miles no longer carry black iron pipe, it's all galvanized. No one there seems to know what kind of steel is under the galvanizing or if it's stronger or weaker than black iron or black steel which they also don't know the difference between.

Lowe's carries black pipe but only up to 1-1/4" dia in a schedule 40 wall thickness and they only have 10' pieces. They will cut it to any length I want but I still pay for the whole 10' which is ~$30. They also have galvanized pipe up to 1-1/4" dia unknown wall thickness but the price is double the black pipe.
 
The way I have found that works best for me is to take the engine out of the ski.
Use your rope method to lock the crank.
Have someone hold the engine still or lean it over and stand on it so it doesn't move. I usually put it on a scrap of carpet or pad to protect the cases.
Use your impeller tool and a breaker bar to put constant pressure on it. They have standard threads to counterclockwise to remove.
I use a MAP gas torch to heat the crap out of the PTO then give the breaker bar a quick hit with a small hand sledge hammer. If it does not come off with two hits then more heat.
The heat is the trick and the paint will blister and chip.
 
I'm thinking the same thing as I'm standing there waiting for a manager to price a piece of pipe left over at the cutting/threading machine. I already tried my butane torch earlier this week and it didn't phase the PTO, so I went down to tools and picked up a MAP kit while waiting for my pipe to be cut to the length I wanted.

Stay tuned and thanks for the tips.
 
Lol, what ever it takes. I refuse to chase an engine around my shop floor. Even my 98 that was full with salt water popped off with little effort.

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Lol, what ever it takes. I refuse to chase an engine around my shop floor. Even my 98 that was full with salt water popped off with little effort.

Sent from my SGH-T889 using Tapatalk

Engine in, engine out, you put your engine in and you shake it all about. You do the hokey pokey and ..... that's what it's all about.

Now what do I do? Jeeze, after reading MikiDyMac's engine mount repair thread, and other threads involving JB Welded mounts, I'm wondering if I should be pulling on that PTO with a 6' steel pipe with the engine in the ski.

I'd hate to pull the mount out of the fiberglass.

I only had my ski in salt water one time a decade ago but some bolts are giving me a fit, especially those lower ones on the engine like the pipe to manifold bolts underneath the pipe. I haven't even gotten to the crankcase bolts on the bottom of the crankcase yet.
 
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On the pto wheel, if you take the crank with it on a machine shop can get it off in 30 sec (that's my avenue, I take it with my cylinders to get them checked, bored, honed and they never charge me anything extra). Or when you get it out you can put the cylinders back on (with out the rings would be faster) put a rag in on top of the pto piston, put the head back on and use a pipe wrench. The last bolt on the mag cover, remove the engine mount, you'll need it out to put the engine back in anyway. Never had any problem getting the pump off, smacked it with a rubber mallet a couple times.
 
The way I have found that works best for me is to take the engine out of the ski.

I use a MAP gas torch to heat the crap out of the PTO then give the breaker bar a quick hit with a small hand sledge hammer. If it does not come off with two hits then more heat.
The heat is the trick and the paint will blister and chip.

Got the MAP torch yesterday, but am wondering now about heating the crap out of the PTO. Would you or anyone happen to know if the PTO is heated treated or at least the area around splines? Never used MAP before, can it get things hot enough to affect the heat treatment, if it exists to harden the splines. Also, how much heat can the rear seal take? Thanks.
 
On the pto wheel, if you take the crank with it on a machine shop can get it off in 30 sec (that's my avenue, I take it with my cylinders to get them checked, bored, honed and they never charge me anything extra). Or when you get it out you can put the cylinders back on (with out the rings would be faster) put a rag in on top of the pto piston, put the head back on and use a pipe wrench. The last bolt on the mag cover, remove the engine mount, you'll need it out to put the engine back in anyway. Never had any problem getting the pump off, smacked it with a rubber mallet a couple times.

Good ideas, thanks. Most of the machine shops I'd use around here stay pretty busy with very big jobs from the many aerospace companies like Lockheed Martin, Northrop Grumman, Harris, etc. When I was at Lockheed we had our own machine shops but I'd often have to offload due to tight government schedules. I'll keep looking.

When you say use a pipe wrench, do you mean on the OD of the part the splines are in? Could it deform it? I bought an impeller tool, is that the wrong thing to use on the PTO or does it do more damage to the splines than grabbing the PTO from the OD?

Also, so is it possible to split the case and remove the crank with the PTO flywheel and the MAG flywheel attached?
 
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Lol, what ever it takes. I refuse to chase an engine around my shop floor. Even my 98 that was full with salt water popped off with little effort.

Sent from my SGH-T889 using Tapatalk

Got the steel pipe, new 1/2" ratchet and pulled, snapped, hammered, and cursed and the PTO just laughed. Put a wet towel under the engine and hit the PTO with a MAP torch until it smoked. Repeated steps 1-4 above and no joy. If the case will split with both flywheels on, I'm going to go ahead and yank the crank.
 
With the MAP gas you will not get it hot enough to hurt the PTO. Let it cool and try it again. Heat the crap out of one spot where the splines contact the large outer weight you are trying to get the heat to the threads. With a small hand sledge hit the breaker bar while applying pressure. Two quick hard hits should do it.
I would pull the engine. You will not damage the mounts this way and it is the heat and sharp smack that will break it free. I wouldn't use the slow strong pull like with a long 6' pipe.

I would replace all the seals when you have it apart so don't worry about the seal.

Yes, the MAG adn PTO need to come off. When you split the cases you need to replace the front and end seals.
 
With the MAP gas you will not get it hot enough to hurt the PTO. Let it cool and try it again. Heat the crap out of one spot where the splines contact the large outer weight you are trying to get the heat to the threads. With a small hand sledge hit the breaker bar while applying pressure. Two quick hard hits should do it.
I would pull the engine. You will not damage the mounts this way and it is the heat and sharp smack that will break it free. I wouldn't use the slow strong pull like with a long 6' pipe.

I would replace all the seals when you have it apart so don't worry about the seal.

Yes, the MAG adn PTO need to come off. When you split the cases you need to replace the front and end seals.

Yeah, it's probably time to pull the engine and give the mounts a break. What do you think about heating it and putting a pipe wrench on the hub to put some pressure on it, and using the impeller tool at the same time with an impact wrench? Good way to ruin the splines?
 
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