Looking to do a top end on my 95 SPI, any tips?

[JUSS10]

So last week I was posting about my SPI having a weird issue where it would run sometimes and then i would get to the dock and try and fire it on the trailer and it wouldn't run then get home and it runs again.... I think that was a fuel issue and i need to replace all the lines and parts in the fuel system.

That said, compression is low and the last time I got it running it seemed to shake a lot. Turns out the motor is coming loose from the engine mount plate.

With all that going on I've decided to do some overhaul work. So a few questions on this engine. I've rebuilt sled engines and this seems a bit similar. Can I do a top end without pulling the engine from the ski? I know its more convenient on the bench but then I'll need that special alignment tool to put it back in if I'm not mistaken. Just pull the cylinders and run them to my local engine shop for them to measure and let me know what i need as far as bore, correct? Just follow the manual to put it back together? Do i need to run premix for the first tank? I did that on my last sled rebuild.

In relation to the question above, as far as the bolts on the engine to the motor mount plate, is there anyway to tighten those while the engine is in the hull or will I have to pull it anyway to get that those? I know its tight under there just thought maybe a ratchet wrench may fit?

Just looking for some tips. Sorry if any of this is common sense, I did a quick search and couldn't find much info.

Justin

 

[mwat65]

You will have to pull the motor to tighten the motor plate up. Run 40-1 premix for break in on the new topend. I believe you can still rent the alignment tool. Someone chime in and let him know where.

 

[etemplet]

I did the top end on my SPI in November. Mine was a pain because I have a Factory Pipe on it. Of course every single bolt but one broke off on the head cover so I needed a new head and cover. Don't worry about a special alignment tool to align the cylinders. I just used the exhaust manifold without a gasket. Clean all the build up out of the water passage areas while your in there and look closely at the gasket surfaces. I used WSM top end kit ... found on Ebay for $189. Good Luck !

 

[Cheflen]

So last week I was posting about my SPI having a weird issue where it would run sometimes and then i would get to the dock and try and fire it on the trailer and it wouldn't run then get home and it runs again.... I think that was a fuel issue and i need to replace all the lines and parts in the fuel system.

That said, compression is low and the last time I got it running it seemed to shake a lot. Turns out the motor is coming loose from the engine mount plate.

With all that going on I've decided to do some overhaul work. So a few questions on this engine. I've rebuilt sled engines and this seems a bit similar. Can I do a top end without pulling the engine from the ski? I know its more convenient on the bench but then I'll need that special alignment tool to put it back in if I'm not mistaken. Just pull the cylinders and run them to my local engine shop for them to measure and let me know what i need as far as bore, correct? Just follow the manual to put it back together? Do i need to run premix for the first tank? I did that on my last sled rebuild.

In relation to the question above, as far as the bolts on the engine to the motor mount plate, is there anyway to tighten those while the engine is in the hull or will I have to pull it anyway to get that those? I know its tight under there just thought maybe a ratchet wrench may fit?

Just looking for some tips. Sorry if any of this is common sense, I did a quick search and couldn't find much info.

Justin

The manual states that you can rebuild your top end in the hull, just make sure you don't lose any circlips or other small parts into the engine, make sure you cover the crank case in towels when replacing the pistons so nothing falls into there.

 

[etemplet]

Yessir, I did mine while in the hull as well. I also recommend making that little block of wood slotted for the connecting rod that fits over the bottom end of the engine. I used a 2x4. It held the piston nice and square and made easy mounting of the cylinder. Wish I could say the same for the circlips. I hate those things. I am considering buying a tool to install them but I don't even know what it looks like.

 

[Cheflen]

Yessir, I did mine while in the hull as well. I also recommend making that little block of wood slotted for the connecting rod that fits over the bottom end of the engine. I used a 2x4. It held the piston nice and square and made easy mounting of the cylinder. Wish I could say the same for the circlips. I hate those things. I am considering buying a tool to install them but I don't even know what it looks like.

Definitely post if you can find a tool or make a tool that helps with those horrible designed circlips because that is worth buying. I don't understand why they didn't just use normal c-clips that have inserts for c-clip pliers

 

[mwat65]

The bolts on his engine plate is loose. He will have to pull the motor and find a engine alignment tool. I bought one years ago. Best money I’ve ever spent , used it many times over the years.

 

[mwat65]

When removing your old pistons rotate your motor so the one your removing is all the way up. Let the piston hang to one side while removing. Stuff paper towels in the crankcase as Cheflen said. If these are original pistons they have careless needle bearings. I forget how many but there are a bunch and if even one gets in the crankcase you will have to split the cases to get it out.

 

[mwat65]

That shouldve read Cageless needle bearings not careless .

 

[etemplet]

Ha ha... I found that out (needle bearings) while doing the top end on the SPX. Reminds me of my old motorcycle days. I always stuff rags and well made strong paper towels in there but boy was a Glad I did that time. I was wondering how many needles were in there but pretty confident none got into the engine. I caught it pretty quick

 

[JUSS10]

Thanks for all the tips!

yeah needle bearings suck on these. I have a 717 on the bench and didn't know these weren't caged so lucky for me I had already stuffed rags under the piston and caught them all.

Yeah since the motor bolts are loose (i think that's what it is, I can rock the motor back and forth a little but don't see the motor plate moving) I'll have to pull the engine.

It looks like osdparts.com rents out the alignment tool. How much does a whole kit cost? I'm considering just buying it as I have a few seadoos and I doubt this will be the last time I pull an engine. Plus i bet I could rent it out locally as we have a lot seadoos around here (west michigan by the lake) so I would think with time i may be able to recoup some costs of the tool kit.

Another question regarding bolts when putting it back together. I know the manual is pretty good about calling out where RTV or loctite needs to go, but on my sled engines, I added some never seize on some of the bolts that go in to the case as the stainless and aluminum like to seize up over time. Is that advised on seadoo engines as well?

Thanks!

 

[etemplet]

I bought my alignment kit off one of the sites and ended up only 40 minute ride from my home. That never happens. LOL I paid $120 used like new. I'd get the kit. I used mine twice already.

On the loosness on your motor. Check closely... you may have a bad motor mount and you can swap that easily. Good Luck !!

 

[JUSS10]

I bought my alignment kit off one of the sites and ended up only 40 minute ride from my home. That never happens. LOL I paid $120 used like new. I'd get the kit. I used mine twice already.

On the loosness on your motor. Check closely... you may have a bad motor mount and you can swap that easily. Good Luck !!

I'll make sure to double check its not a motor mount. Oh how I would love for it to just be a motor mount as that would save the cost of the alignment tool but we'll see.

 

[etemplet]

I'll make sure to double check its not a motor mount. Oh how I would love for it to just be a motor mount as that would save the cost of the alignment tool but we'll see.

Yea... I'm kinda surprised a base mount bolt would loosen up but... bad alignment and vibration, mechanical malpractice and such... ya never know. LOL Hope it is simple for ya. I sure could use some simple right now. Ha ha

 

[JUSS10]

Just checked, definitely a bolt on the bottom of the engine. Not so simple. Oh well, easier to do a top end out of the hull anyway.

 

[JUSS10]

Another question, if the engine shop says the cylinders just need a hone, is it worth buying a whole new top end kit or is honing the cylinders and re-ringing the pistons ok? Looks like rings are around $30 a piston so two sets and a gasket kit I'm looking at around $100 vs around $200 for new pistons, piston pins, bearings, etc. I don't have a problem spending the $200 if its justified. Just curious to hear from those who are more experienced than I am with this.

 

[mikidymac]

Unless the ski was never ridden I haven't seen one that only needed a hone. Did you print out the specs for the engine and give it to them along with your old pistons to measure? They would need both to do it correctly. And I hope they are experienced with 2 strokes because most machine shops I have seen don't chamfer the ports enough or at all. I send all my cylinders to Group K for boring.

 

[JUSS10]

haven't even got the top end off yet. I had them do my sled and they seem to have plenty of power sports engines sitting there when I've had them do other things.

I'll be sure to bring the cylinders, pistons and engine specs when I drop them off.

 

[etemplet]

It is easy enough to run a hone through the cylinders if you have micrometers to check the size. I honed the cylinders on my SPI. They were in spec. I installed new pistons when I did mine but I had some damage on the PTO piston. One thing buying new pistons gives you a closer fit concerning the piston to bore clearance. Kinda like stealing a little but mic them to be sure.

 

[JUSS10]

engine is out and head is off. IT definitely needs some work. Not awful scoring but not surprising for an engine that is 23 years old. It appears I'm the first person to ever open the engine up. Hope to get the cylinders off in the next few days.

Reading through the manual, it talks about a synthetic grease to put on the bolts. I can clearly see that there was grease on these. What do you all use when putting it back together? Is there something off the shelf or should I go to the dealership and get the grease that they listed in the manual?

 

[mwat65]

Don’t forget to stuff towels around the rods in the crank opening so you don’t get any needle bearings in there when you remove the pistons.

 

[JUSS10]

Got the pistons and cylinders pulled. definitely need a boring. There was a fair bit of scoring on the intake side of the pistons. Weird thing, the needle bearings were caged. I swear its never been opened before though as the base gasket has paint on it where it was outside of the cylinders. Guess it doesn't really matter, just made my life easier when I pulled the pistons.

Cylinders are at the engine shop and should know by the end of the day what i need to order for a top end kit. Which leads me to my next question. I don't want to start a argument on pistons (I ran in to this with my polaris sled i rebuilt last year). Was planning to just do a WSM top end. I see they have a standard and a coated platinum (they almost look like pro x pistons). Any input on whats better? Also is it worth a little more to go to the pro x pistons or should I be fine running the WSM pistons for normal use. It is an SPI after all so not a crazy performance machine.

Also see SBT sells a top end kit for $260.

input welcome.

Justin

 

[mikidymac]

I would stay away from SBT but that's just me. I have been using WSM pistons for 25 years with no issues and on an SP I'm not sure the Platinum is worth the extra money. I prefer OEM pistons over all others but for your engine I would go WSM.

Contact @hfgreg at PWC Muscle and he will hook you up with WSM parts as a forum member and fast shipping.

 

[JUSS10]

Thanks! I just shot him a message.

 

[Chester]

Don't forget to replace the crank seals and carefully inspect each bearing. There is no such thing as "just a top end" on a PWC.

Chester