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Hey Guys!! I'm new to this site as of right now, and looking forward to relaying my knowledge and experiences with my machines.
So I have this sled, 1986 Phazer 480. This thing has not ran right in almost 8years now, and I just have not had the time to figure it out. Well...with all this COVID stuff going on....I now have the time. Here's the issue.....
When you first start the sled, it sounds like its running well, but soon starts to sound like it's missing. If you try and give it throttle, it just bogs and dies. The exhaust it smells heavily of fuel and when you pull the plugs, they are fouled and wet. The sled has about 6000kms on it as well.
Here is what I've looked into and or checked....
Pulled carbs and gave a thorough cleaning, and installed a rebuild kit, needle jet and seat, rejet the carbs to a 137.5, which according to the jet chart in my Haynes manual should be good for 3000' and -15C, set the floats to 12.5mm (they were at 9-10mm, manual calls for 11-13mm), and also set the mixture screws to 1.5 turns out, as per the manual.
Installed carbs, and no change in how it runs. Did a compression test, getting 92psi on each cylinder. started the sled and sprayed some brakleen around the base of the engine to check for vaccuum leaks....no increase in rpm at all. I did try and disconnect the TORS switch to see if it was malfunctioning, and still no change. So as of two nights ago, I have started pulling the sled apart to check all the wiring and test the fuel pump. So far, only found a ground wire for the tail light rubbed through, and the fuel pump looks to be working fine when I pull the starter cord. I haven' gotten to the stator just yet for testing, but all my lights work good when the sled it running, even when not running good, so I'd think the stator is ok. I have disconnected the hand grip warmers, just to eliminate them as a power draw, and yet, still no change in how its running. So i'm almost out of ideas here and I'm hoping someone may have had a similar issue and a solution. Can anyone tell me what is acceptable compression? What range should I be in with this sled. With low compression, I could understand the sled not moving, but would it cause it to miss, or sound like it is? At any rate, the plugs are fouling, so it's getting too much fuel it would seem right. Would the 2mm difference in the float height be enough to cause an over fuel issue? Another question.....what about a CDI? Is it possible for the CDI to be failing like this and causing intermittent spark? The sled USED to run good when it was stone cold, and then start to miss as it warmed up, could the CDI have been doing the same thing, till it get warm, then starts acting up? The last thing is have it the cylinders...I put my micrometer on them tonight and they are 72.230mm diameter, and factory says they are 72mm even. Not sure how much error to alot to the micrometer and /or the operator....:) any ideas or help anyone can offer up wold be greatly appreciated.
Thanks in advance
Jason
 

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92 psi is really low. What it should be is at least 120. Also, you really can't test the stator side seal that easily for air leaks. It could still be a problem as well. I personally think if you fix your compression problem it'll work better. And while I would be in teardown mode I'd ohm out the stator windings too but I haven't heard of them being a problem or the cdi on a phazer.

Steve
 

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Welcome
Compression is too low
Sounds like you have it apart already.
Your floats, I don't believe in a measurement.
Try simply blowing into the inlet with your mouth and raise the float till you can't pass air,
this should happen as the float becomes 'LEVEL' with carb body.
As for the jugs I would have them bored and get a pair of new pistons and a complete gasket set with seals and go through the hole thing!
I can look them up for you but my cost on pistons is about $50 and the gasket set is even less usually!
 

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Discussion Starter #4
Thanks for the replies Steve and KC!! So compression hey.....ok. I was kind of wondering that as well. But with the low compression, would it still cause my plugs to foul and be wet? If so, how if the plugs DO spark when I pull the machine over, and it appears to be consistent. Would the low compression cause a mixture thing? I’ve noticed after running before that it leaves a puddle under the area where the exhaust comes out, so it’s definitely not burning the fuel fully.
As far as the floats go, I did just that. Blew lightly into the fuel port and raised the float until I’m pinched off the air, and yes....it’s level with the body,
so I’d agreee in saying they should be set right.
Thank you for the offer KC on the pistons etc, it’s much appreciated, but I’m up in Alberta, Canada. I have a buddy who works at a Doo dealership who can get me the parts at a pretty good discounted price. I’ll have to get the jugs to him anyway.
I’ll keep you posted.....
 

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Low compression causes a multitude of problems. Fouling plugs and lousy running are common. Lame throttle response comes to mind too. Spark comes from the stator. Plain and simple. Puddles also come from the combusion process and cold pipes along with heat causing condensation. Just like your car blows water out the tail pipe when warming up.

Steve
 

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I plan on going threw the Phazer I bought last fall as well.
I am going all the way with this Ditch Banger for MY personal sled (revamp my Ovation)
Over sized pistons, .025 off the heads, Mod the exhaust, and Boyseen reeds
Then wedge it back into my Ovation with a 1" 121 track and a Mod M10 type skid.
 

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That would make that Ovation a fun ride. I rode one at a demo ride one year. The real problem with it was it was soooo light that it would "bounce" off the moguls. IMO you need some weight just to allow things to work better like suspension over bumps.

Steve
 

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Discussion Starter #8
That would make that Ovation a fun ride. I rode one at a demo ride one year. The real problem with it was it was soooo light that it would "bounce" off the moguls. IMO you need some weight just to allow things to work better like suspension over bumps.

Steve
 

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Just an update....I pulled the jugs and pistons. Clutch side looks to be not too bad, but the fan side is scored. Looks like a stuck ring. Will be taking them to my buddy today to get bored and measured for new pistons. Also ordering a complete gasket set to go with it so compression should be at its best once back together. Right now the engine is on my bench. Want to go through the wiring and replace the fuel lines as well as give the belly pan a good degreasing and cleaning. Will keep you posted....and thanks for advise up till now!!
65050
65051
65049
 

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Ouch man, I just picked up an 87 last week. Kid told me it ran great pulled and pulled he couldn't get it running. Paid him $150 for it vause it was all there. Got it home tore out the skid pulled the motor. Pto side piston broke the skirt and a ring stuck. Cylinders are not hurt (how i have no idea). Putting in a 136' 1.75 skid and track. Looking for a manual now to get the motor finished up with specs.
 

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I would be concerned about that piston!
Also look at your heads!
Any little pit marks will cause hot spots!
I would at least take.020 off the mating surface and sand down any pits in dome!
It is really simple, just chuck it up in Lathe on the spark plug!
 

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Is the B side the mag side? The B side piston looks like it has a lack of piston wash, which could indicate a leaking crankcase seal behind the magneto. Does the gasket kit include replacing the crank seals? If that seal was the problem, not replacing it will end up with another burned piston.
 

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Discussion Starter #13
Is the B side the mag side? The B side piston looks like it has a lack of piston wash, which could indicate a leaking crankcase seal behind the magneto. Does the gasket kit include replacing the crank seals? If that seal was the problem, not replacing it will end up with another burned piston.
Yes...the B is the stator side. That piston scarred up pretty good. Had a stuck ring on that one.
when I was doing my original troubleshooting, the local mechanic said to spray some brakleen down around the base and either end of the case, and if there was a leak you would have the rpm pick up. I did that with no change in rpm. But I’m going to talk to the shop today about getting a seal kit for it too.
 

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Discussion Starter #14
I would be concerned about that piston!
Also look at your heads!
Any little pit marks will cause hot spots!
I would at least take.020 off the mating surface and sand down any pits in dome!
It is really simple, just chuck it up in Lathe on the spark plug!
I dropped the heads, pistons and cylinders off at the shop yesterday. They called in the afternoon...heads were good, definiately needs new pistons, and they needed to take .015 off the cylinders to clean them up.
 

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Discussion Starter #15
Ouch man, I just picked up an 87 last week. Kid told me it ran great pulled and pulled he couldn't get it running. Paid him $150 for it vause it was all there. Got it home tore out the skid pulled the motor. Pto side piston broke the skirt and a ring stuck. Cylinders are not hurt (how i have no idea). Putting in a 136' 1.75 skid and track. Looking for a manual now to get the motor finished up with specs.
Would like you’ll have a great machine once you’re done! I have a Haynes manual for my Phazer.....it gives You most of your basic specs....so far the only thing I’ve had to look for was factory cylinder specs, but these forums have a ton of info on them too!!
Good luck!
 

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Hang on here, you will need to get a set of (OEM) pistons , they come in over sized for your cast cylinders.
Once you have the correct pistons THEN have your guy bore and hone to fit pistons!
Taking .020-.050 off the heads will increase compression later!
I have .40 over in my SRV and took .040 off the heads and my compression is 125
Remember this little Fanner only had 115-120 stock!
 

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Hang on here, you will need to get a set of (OEM) pistons , they come in over sized for your cast cylinders.
Once you have the correct pistons THEN have your guy bore and hone to fit pistons!
Taking .020-.050 off the heads will increase compression later!
I have .40 over in my SRV and took .040 off the heads and my compression is 125
Remember this little Fanner only had 115-120 stock!
Sorry..I worded that wrong....didn’t mean to imply they had done the boring already, they just cleaned up the cylinders to see how bad they were and if they were figured they were still useable, and figured 0.015 would do the trick. They didn’t home or bore anything yet. Waiting on the pistons and gaskets to get here before touching the jugs.
 
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