485 won't run on right cylinder

longtrack156 · Feb 23, 2010

Old Phazer engine won't run on right cylinder, it has a primer on it, if I keep priming it, it will run, (drove 15 miles to get it home pumping the primer). It seems like the venturi effect is not there for the right cylinder.

Float bowl full of gas.
Compression is good.
Cleaned the carbs many many times.
Reed valves look good.
Pulled the crank, seals look good.
New needle and seats.
Piston skirt looks good.
Swapped carbs.

I'M STUMPED!

MotoPsycho · Feb 25, 2010

Do a crank case leak down test...

I think the procedure is: seal case and pressure to 3 psi let sit for 30 minutes - don't remember what allowable loss is; I think 1/2 lb.

longtrack156 · Feb 27, 2010

After trying lots of things last year I pulled the engine and took the crankcase apart to see if I had a bad seal, everything looks good and the crankcase went back together with lots of sealer on the gasket. I have lost drain plug in the case before, it doesn't quit firing completely like this does.
Dealing with this old junk I think the problem is just that, old junk. The old sled is a joy to drive though so I would like to get it running. I have a new clue, the old carbs were missing all but one gasket that goes on the main jet bolt, it seems to be about .040 thou. I made a plastic washer but I don't think it was thick enough and the main jet seems to run into the siphon tube in the carb. I will make some .040 washers and try that.

sledmaniak · Mar 6, 2010

old phazer 485

I have never seen a 485 with drain plugs for the case. It sounds like a lack of fuel for sure. also primer? this must be a aftermarket set up? the oe system has never let me down. I would try putting the vac caps back on the carbs where the primer sys hooks up. The washer for the bolt that holds the main jet was orig aluminum some one must have a set of old carbs for phazer laying around. Oh and one more thing make sure that the holes in the inlet side (air box) side of the carbs are not pluged. There are three. as you are looking at them the left one is blank. Middle is the air bleed for main tube and right is the air bleed for pilot ( extreamly small hole)!

northern turbo · Mar 7, 2010

phazer carbs

I recently put together a 94 phazer. it ran on one cylinder until the choke was on and then
the second one fired.Lack of fuel i assumed ,cleaned the carbs , ran small wire through all the ports,no change.Finally I took the air screw out and ran a torch tip cleaner in the port
and just like that ,started and ran on both cylinders.Had to repeat cleaning a few times, but runs good now.Just something you may want to try,or maybe have already.....?

longtrack156 · Mar 7, 2010

The old carbs had lost their aluminum washers on the main jet except one, I replaced them with plastic washers.
The aluminum washers were .040, the plastic washers were .030, I made some new aluminum washers, as far as I can tell the problem is solved.
I haven't field tested it, but in the yard it works.

longtrack156 · Mar 7, 2010

sledmaniak said:
I have never seen a 485 with drain plugs for the case. It sounds like a lack of fuel for sure. also primer? this must be a aftermarket set up? the oe system has never let me down. I would try putting the vac caps back on the carbs where the primer sys hooks up. The washer for the bolt that holds the main jet was orig aluminum some one must have a set of old carbs for phazer laying around. Oh and one more thing make sure that the holes in the inlet side (air box) side of the carbs are not pluged. There are three. as you are looking at them the left one is blank. Middle is the air bleed for main tube and right is the air bleed for pilot ( extreamly small hole)!

Case drain was on a different sled, this is one different Phazer.

Search

485 won't run on right cylinder

longtrack156

Free Member

MotoPsycho

Well-known member

longtrack156

Free Member

sledmaniak

New member

northern turbo

Free Member

longtrack156

Free Member

longtrack156

Free Member

Similar threads