95 Phazer 2 top end damage, wonder what happened here

fangard

New member
Joined
Nov 12, 2016
Messages
8
Location
Wisconsin
Bought a 95 Phazer 2 with 2700 miles on it. Went through the thing, including carb cleaning and basic checks. Put it all back together, took her for a short ride and all seemed fine. I did notice when purchased and when put back together, that it was a "hard" starter, but nothing 8-10 pulls didn't take care of.

Got ready to take her for a longer ride, died on me at idle while getting helmet on. Couldn't get it restarted, ran to the garage and grabbed some starting fluid. Got it to start and off I went. Rode 10 miles and parked. 1 hour later, attempted to start with no luck even with the starting fluid.

Picked the Phazer up and finally got around to taking a look this past weekend. I found bad compression out of both cylinders. 30 and 50...ugh. Ripped into the top end and this is what I found. Now I would like to find the cause so this doesn't happen again after a new top end goes in.

I heard that ether is terrible on a 2 stroke. Could this damage have been caused by the ether I wonder? Left side cylinder seemed to have what looks to be maybe a ring issue. Bore is clean with cross hatching still visible. Right hand cylinder (mag side) looks like a bee bee was banging around in there. Small pits all over the head and cylinder top. Bore has been slightly compromised, but barley noticeable.





 

Looks like the locating pin came out of the piston (holds the ring from spinning). Make sure you pull the motor and split the cases to clean everything out of the bottom end...
 
could be locating pin from piston but thinking with the prior hard starting issue the crank seals where out of the sled and part of the spring or part of a bearing came loose regardless of what you find the whole engine needs to come apart and be inspected. and one other tip ..............NEVER USE STARTING FLUID ON A 2 STROKE that alone may have done your engine in
 
Thank you guys for the replies. Now the fun begins eh? I would consider myself handy enough to get to the point that I'm at now, but as far as ripping the motor out and getting to the bottom end....hmm. Was hoping I would not have to take it this far on a $700 machine that I "thought" was mint.

I have noticed that the more I dig into this engine the more I realize how simple it is, but is a bit out of my comfort zone. Sometimes it's just best to bull forward and learn as you go :)

How do I handle the cylinder jugs? The clutch side looks good with cross hatching still visible and think that it will be good to go. The mag side wall has slight imperfection - slight. What do I do about this? Is a bore the only fix? Can I just hone and the rings take up the slight imperfection? Do I just find a used phazer and engine swap? I seem to be treading into an area I am not to familiar with. I did just obtain the service manual = Huge help.

Should ether be avoided in all internal combustion engines? Why does it harm 2 strokes so badly? Predetonation?

This forum is the bomb by the way. What did people do before the internet?
 
Yamaha Nutz and I are both in Wisconsin and both have cylinders if you need one. If you can feel the imperfection in the cylinder then you may need a replacement or bore. Im going to go with bad crank seals wich lead to detonation and gave you the hard starting. A properly maintained Phazer is a 3 pull max sled. If the locatating pin did come out, the side of the piston is usually gouged horribly.
The reason you dont want to use starting fluid in a 2stroke is that ether is a very good solvent and washes the oil off the internal parts of an engine instantly. Also the vapors can ignite in the bottom end resulting in blown out crank seals or base gaskets.
 
If you have to use a starting aid - which does not normally happen - use mixed gas. The compression was probably low when you got the sled, that would have caused the hard starting. If it looks like fresh crosshatching, it may have just been rebuilt - and possibly debris was left inside. The right piston looks pretty clean.
You could talk to the previous owner. There is a chance he would give something toward a repair.
It is not expensive if you have to bore the cylinder.
 
Progress has been made. I had to enlist the help of my neighborhood friendly spiderman, but engine is now out and new parts have been ordered. Should have pulled the primary clutch while engine was still in the chassis. Planning on using the water trick to get that sucker off.

Ordered a new / used mag side cylinder and head off of ebay. Ordered a full gasket and oil seal set from Dennis Kirk. Ordered a new set of Wiseco pistons. Also ordered a honing tool for my cordless drill. The three arm stone type. Noticed that the new pistons don't come with cage bearings. Can I reuse the previous ones? I ordered 2 new ones from Dennis Kirk just in case - Kimpex brand cage bearings.

Sure is easy to rip stuff apart, we'll see how I do on getting this thing back together. Concerns that I am sure I will encounter = Timing, will I find the timing to be easy and clearly marked on the engine?

Sure hope I ordered the right pistons. I have a cheap digital caliper and measured 72.52mm at the skirt of the previous set of pistons. I ordered the standard bore set. I see the service manual stated the skirt measurement should be 72.94mm

Are all phazer PZ480 = 485cc engines the same? 1984-99?

Let the rebuild begin :)



 
When using wiseco pistons, make sure you warm the sled up good before taking off. The wisecos are forged, OEM are cast, the forged pistons will expand quicker than a cast piston increasing your chances of a cold seizure. The engines are the same from 84-99, I think the later ones had different stators but the top and bottom ends were the same.
 
just my personal opinion and have to ask why did you go with WISECO pistons? it will now be very important to check the skirt clearance which should be set at .004'' for the phazer if not you will stick a piston cold or warm and you now must be mindful to always warm the sled up good. Have your cylinders checked for taper and out of round and that should have been done be for ordering pistons in case they need to be bored
 
just my personal opinion and have to ask why did you go with WISECO pistons? it will now be very important to check the skirt clearance which should be set at .004'' for the phazer if not you will stick a piston cold or warm and you now must be mindful to always warm the sled up good. Have your cylinders checked for taper and out of round and that should have been done be for ordering pistons in case they need to be bored
Well, that's not good. I ordered the Wiseco only because of doing a small amount of research on pistons. Guess I should have just asked here :( Perhaps an order cancel is in order. Cast is the way to go? I just read many posts about how engine builders only go with Wiseco. I will get on the phone now to cancel this order.

Thanks again for all the guidance and info I have received here!
 
Fangard, why not support the members on the site that are giving you info?? Yamaha Nutz and I are in SE Wisconsin and we would have been more than happy to help you out with parts. I hope your build goes well.
 
Wiseco .....well as far as that goes they are my last choice when building a engine unless there is no other choice, because of port work or over bore needs
 
Fangard, why not support the members on the site that are giving you info?? Yamaha Nutz and I are in SE Wisconsin and we would have been more than happy to help you out with parts. I hope your build goes well.
Thank you for bringing that to my attention. Please excuse my newness as I am note sure as to who is who yet in this forum. I certainly do appreciate the offer you gave about having cylinder jugs. I have canceled my Wiseco piston order and am now working with forum member shaggyzr2 who has informed me that he can get me SPI pistons and all related parts.

Now I just need to know what size pistons to order. Here are some pics I took of the pistons that came out along with some markings.
I followed the manual to measure 10mm up from the bottom of the piston. From what I can tell, these look to be the standard piston.

Do I need to then order the 72mm pistons from SPI ?







 
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Fangard, why not support the members on the site that are giving you info?? Yamaha Nutz and I are in SE Wisconsin and we would have been more than happy to help you out with parts. I hope your build goes well.
Thank you for bringing that to my attention. Please excuse my newness as I am not sure as to who is who yet in this forum. I certainly do appreciate the offer you gave about having cylinder jugs. I have canceled my Wiseco piston order and am now working with forum member shaggyzr2 who has informed me that he can get me SPI pistons and all related parts.

Now I just need to know what size pistons to order. Here are some pics I took of the pistons that came out along with some markings.
I followed the manual to measure 10mm up from the bottom of the piston. From what I can tell, these look to be the standard piston.

Do I need to then order the 72mm pistons from SPI ?







 
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You should actually measure the bore instead of the piston. Your not using the old piston so that measurement is almost useless.
 
If you don't have the tools to measure the cylinder bore you could take it in to a machine shop, they can measure it for you.
 
Well,
Finally got around to ripping into the bottom end and cracking the case apart per the advice of this helpful board.
Bottom end is shot. The mag side crankshaft bearing was missing roller balls and just fell apart. Other bearings are making noise and don't roll more than a single revolution when spinning by hand. Case halves are compromised too. Pretty beat up from all the loose metal flying around.
Looks like this was caused by a bad crank seal on the mag side.

I am in the market for a new phazer motor :)

Thank you all for your input
 


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