Hi,
I've found a few forum posts in the past where someone asked for a part and got a list of compatible parts/newer parts that match, though I'm unsure of how exactly they got that list if not from the parts searching diagrams like bikebandit.

I'm looking for several parts that are no longer produced or for sale for my 1987 Trail Boss 250 2x4 W877527

• Inner Clutch Cover 2200803
• Outer Clutch Cover 5430771
• Inner Clutch Cover Gasket/Seal 5410411 <--- MOST INTERESTED IN THIS ONE, CAN'T FIND ANY OEM FOR SALE, DO THESE FIT FROM NEWER YEARS?
• Crank Oil Seal 3082162

A more general version of my question would be if i could swap out the inner and outer clutch covers from other models (as long as they are both in a set) and throw them on.
Sorry if this seems a little hand-holdy, but if you could even just point me in the right direction of a website that has a list available of interchangeable parts between old and new parts it would save me a world of trouble.


EDIT: After searching for a few more hours, I found this:

Go to http://parts.polarisind.com/Browse/Browse.asp
Put in your information, then find your part.
On the left there should be a tab with the part #'s and descriptions. Drag the little divider between the diagram and the parts list and you'll see a hidden column with 'usage'.
Click usage to see all models that use that specific part.

That doesn't necessarily let me know if I could just swap out a newer year cover on, though

 

Welcome to the forum. The link you have for the Inner Clutch Cover shows it as available for $87.95. The Outer Clutch Cover may have been updated to another part, like they were on some other models, but the Polaris Parts site should show that. I'll take a quick look myself.

 

Hi, that'd be much appreciated. My main concern is that the older models had plastic covers that sagged upon overheating easily and I wouldn't want to buy a new one that will end up the same. The OEM outer cover does me no good alone since the inside gasket is completely shredded and there's no replacement for that one. I found a 2002 replacement both inner and outer cover that I think might fit, and there's still gaskets being sold for it. I might just end up sawing off some of the plastic spacers and hope it fits.
What do you think?
If the spacing between the primary and driven clutch hasn't changed in years it should work out...

 

It might work. Some covers were updated because of that sagging. You can click on advanced search on the Polaris Parts site and enter your part number to get a list of which models they fit. Maybe you can get something used at a place like ebay. Here's what I got for that seal. http://parts.polarisind.com/OtherAss...partid=5410411

 

I ended up pulling the trigger on a newer clutch cover (both inside and outside, since they have to match) as well as a new seal for them. They should arrive this week and i'll update with part numbers once I get them and check for fitment.

As a side note, I'm posting this so if anyone ever stumbles upon this it might help them:
For the OEM crank seals that have a metal outer casing and a rubber insert, the original number found on the seal itself was " TB 30 44 7 ", the numbers being the Inner Diameter, Outer Diameter, and thickness. Note that if you search for the Polaris part number you won't get any results since it's currently a 30 year old part. If you google the actual oil seal number, you won't get any TB results, but you will get TC results.

From http://ph.parker.com/us/en/general-p...seals-tb-tc-ta

• Standard Designs:
  • TB Profile: Metal case with ParKote™ bore sealant or ground OD. Most common and economical
  • TC Profile: Rubber covered metal case OD for improved OD sealing in bores with minor imperfections and in soft alloy housings
  • TA Profile: Double metal case where inner case provides structural rigidity for large cross-sections. ParKote™ coating is standard

It seems as though the TC oil seal with the same dimension might actually be better than replacing it with an original TB (if you can find one) , since the rubber outside edge will help seal the imperfect, worn crankshaft better.

In my case the original TB oil seal was blown out completely, which meant the fuel/air mixture from the carb (which was properly receiving gas and giving out a fuel/air mix) wasn't being sucked into the crank/cylinder due to no vacuum. After my dad and I nearly tore our arms out of their sockets trying to pull-start it while diagnosing issues, there was a single sputter when we put in some starter fluid. The small cloud of smoke that this sputter created blew out through the pull-starter case, which ended up being the side where the seal that was completely shot.
As a side note, if you've got a smoker in the family, you can ask them to light up and blow some smoke in through the same hole where the carb would provide its air/gas mix.Turn the crank until it's blocking the ports and if your crank seal is so completely fucked up like mine was, you'll have smoke coming out of the side that's shot.

The previous owner claimed it wouldn't start due to very low compression. Since we had a dry plug, the carb worked, and we had spark, that would point to either having a huge hole in the piston head (easily verifiable) or a bad crank seal.
As a side note, to pull the primary clutch off, you'll need a 3/4 inch FINE THREAD bolt. in NYC neither Home Depot nor Lowes had them, and no fastener place I checked had one either. Either buy or unscrew a trailer hitch ball and you'll have it! You need about 2 to 2.5 inches of thread to get it in but it beats paying for a clutch remover. You'll also need to put in either water for hydraulic pressure to pop it off, or use a socket extension to press up against flywheel (be careful about not pushing up against the threads!) People claim you might damage the clutch threads (not exactly sure how but whatever)but if it's a 30 year old machine you're fucked regardless of what you do- save the money and put it in elsewhere. If you've got a newer ATV it's probably better to just buy it on Amazon and have it perfectly set up.

Don't bother spending money on a flywheel puller either if you can just go to Home Depot and get the matching bolts for the puller holes (the three small ones surrounding the center hole). These are 1 inch on center from the center hole, and are spaced 120 degrees apart (measured with a caliper to make sure). Saves you 16 bucks. Don't for the love of god try pulling the flywheel with a pry bar or screw driver. It's expensive to replace (or impossible if your machine is old enough). Also be VERY CAREFUL to not thread your flywheel puller bolts too far and hit the stator wires directly below!

I'll post more when we get our engine back together. The seal is in my mailbox as I write this! I'm quite excited.

If you're reading this thread in the future and you have the same model and have questions about taking the thing apart, shoot me an email (mikew96@gmail.com)