shortbus Posted April 7, 2004 Report Share Posted April 7, 2004 I have no clue what is going on with this thing. Hopefully someone can help. Here's the deal. When idling the right side exhaust blows TONS of smoke,,, to the point that there is a puddle of oil on the ground underneath it. Right side is barely puffing smoke. The idle adjustment has hardly any effect on idle rpm,s except for No idling/way to high idling. there is no happy medium. It fowls plugs after about 20 mins of riding. It runs good past half throttle. I just replaced the crankshaft and installed new seals, wristpin bearings. The pistons were new when i bought the quad (about a month ago) but I noticed who ever bored the jugs sucked. The piston to cylinder clearance is not good, i didn't measure but it looked close to about .020 per side (outch, I know). This is the only thing I can think of that might be causing these problems??? I tried swapping reed cages side to side,swapped plug wires, no effect. The compression on both cylinders is 120psi, thats why I left the topend like it was. The quad has a TRINITY STAGE IV intake with a 34mm kehien PJ carb I know the right side crank seal can suck oil from the tranny and I'm not rulling that out but I think it is unlikely because I just changed them and prelubed the new ones good. I don't think it is burning antifreeze or oil because niether levels have changed. I dont know what else it could be besides the piston to cylinder clearance. Can this effect the amount of fuel drawn in to the cylinders? Quote Link to comment Share on other sites More sharing options...
jrm312 Posted April 7, 2004 Report Share Posted April 7, 2004 did you check the slides are in the right way. concaved side to the back and are your carb insync Quote Link to comment Share on other sites More sharing options...
shortbus Posted April 7, 2004 Author Report Share Posted April 7, 2004 This quad has a single 34mm kiehin pj carb (trinity stage IV). Thats whats confusing me. Quote Link to comment Share on other sites More sharing options...
SDD Posted April 7, 2004 Report Share Posted April 7, 2004 You said it fouls plug about every 20 mins... what do the plugs look like? Have you compared them to the other side? What color is the smoke? It doesn't take much coolant or oil to cause it to smoke quite a bit. You say you can't get a nice smooth transition with the idle adjustment so I'd look for an airleak. Does the smoke smell sweet like coolant? Did you use any oil to prelube any bearings (crank, wristpin,...) and how long have you run it since you put it back together? Quote Link to comment Share on other sites More sharing options...
shortbus Posted April 7, 2004 Author Report Share Posted April 7, 2004 The plugs are both black in color. The smoke is blueish white, both sides smell the same. Nothing like sweet or foul smelling. Yes I lubed all seals bearings everything while building it. Actually the quad had these same sypmtoms before rebuilding the bottom end. The reason for the bottom end rebuild is because the crank bearings were bad. the bottom end was rebuilt about 2 weeks ago. The pilot in the carb was a #50 now it has a #48. With the #50 pilot the air screw likes to be at 1.75 turns out, so the #48 should be lean right? It smokes like crazy out the right side with both pilots. Oil ratio is 40:1 golden spectro. I don't think it has an air leak as it is rich on both plugs as it is. But I have not done a leakdown test on it. So I can't rule that out. Quote Link to comment Share on other sites More sharing options...
SDD Posted April 7, 2004 Report Share Posted April 7, 2004 Does your Banshee have an aftermarket head on it? Even though the levels haven't changed and the smoke is a oily smoke (blue) it never hurts to find out. I would do a leak down test just incase. Do you let the bike warm up for long periods of time? It just sounds like on side is getting more fuel flow than the other which could happen if one of the reeds is cracked. Try swapping the plug wires from side to side and see if it causes the other side to smoke more. Thats just about everything I can think of causing one side to smoke more than another besides one cylinder having a looser fit. Quote Link to comment Share on other sites More sharing options...
boonman Posted April 7, 2004 Report Share Posted April 7, 2004 Your right side crank seal is shot, and causing that side to suck in tranny oil. I bet it smells like complete ass!!!! Time for a rebuild!!! If it was coolant, it would smell sweet, and be white. However, it would likely not foul the plug(s). Check your tranny oil level. I bet it's low...... Quote Link to comment Share on other sites More sharing options...
shortbus Posted April 7, 2004 Author Report Share Posted April 7, 2004 The exhaust smells fine. the oil level has not changed at all in about two weeks of riding time. I swapped the plug wires and no change. I swapped the reed cages and inspected the reeds, nothing wrong. The lower end was just rebuilt and I'm possitive its not the crank seal. Quote Link to comment Share on other sites More sharing options...
boonman Posted April 7, 2004 Report Share Posted April 7, 2004 What is the compression of that engine? What is the differenct between the cylinders??? Quote Link to comment Share on other sites More sharing options...
banshee76179 Posted April 7, 2004 Report Share Posted April 7, 2004 rings? Quote Link to comment Share on other sites More sharing options...
OC-SHEE Posted April 7, 2004 Report Share Posted April 7, 2004 yeah i really feel you should either replace your rings since you took the top end out and if you feel the bore is bad i would really bring it to be rebored and you will need new pistons. But you should get new rings and try that first. Quote Link to comment Share on other sites More sharing options...
shortbus Posted April 8, 2004 Author Report Share Posted April 8, 2004 The compression is 122 psi on both cylinders. I think I have it figured out. It's getting worse by the minute of running time. I believe the case halves are leaking oil into the crankcase area. I used yamabond number 4 on the case halves but found that it was drying very fast when I was puting it on. It was hard to get the stuff down around the seals and bearings. By the time I got both case halves coated in the shit, the first one was almost dry. Are there any tricks to doing this or just work fast and aplly a bunch of it. I put it on thin like the directions said to. I really think this is the problem. Quote Link to comment Share on other sites More sharing options...
shortbus Posted April 8, 2004 Author Report Share Posted April 8, 2004 Ok, I removed the engine and tore it all down to pieces. On the bottom of both jugs there is a rubber plug. Around these plugs on the base gasket it looks a little wet. Not much but if I push on the plug some coolant leaks out. Can I replace these plugs or remove them and fill the holes with high temp rtv? Both base gaskets are just barely wet around the plugs so I'm not possitive that coolant was leaking into the cylinder. Also I looked at the right crank seal and it looks good but there are some very small grooves worn into the gear/collar that the seal rides on. Is this gear normaly replaced on a lower end rebuild? The grooves don't look deep enough to cause it to leak. And should I put some yamabond on the outer edge of the crank seals to help them seal in there bore? I need to do this the right way this time so I have NO leaks. Quote Link to comment Share on other sites More sharing options...
boonman Posted April 8, 2004 Report Share Posted April 8, 2004 Yamabond "never" actually dries. It tacks up, but it is a permeable gasket maker. Good shit IMHO. When I assemble a lower end, I yamabond EVERYTHING. Every gasket, seal, anything that goes between the case halves, get yamabonded. I have never had a problem with case halves.... When I apply it, I use my finger, and run it around everything. Make damn sure everything is spotless before you apply it. I use a small grinder with a polishing pad. I also use a razor blade. I also lacquer thinner on a rag everything to make sure there is no oil or anything. SOmetimes mineral spirits from the parts washer can be a bitch..... And that shit will wipe out a bearing in seconds.... Cleanliness is next to Godliness. Take your time this go-round. Double check everything. Yamabond the shit out of it. If your crank seal was shit, you should have oil in the bottom of the right side case..... (under the cylinder). I doubt that coolant was getting past the plugs, but they have gone bead before..... You can get replacements from Yamaha. Quote Link to comment Share on other sites More sharing options...
shortbus Posted April 9, 2004 Author Report Share Posted April 9, 2004 Back together and running now!!! NO SMOKE!!!!!!!!!!!!!!!!!!!! I pulled the rubber plugs out and they didn't have any kind of sealant on them. So I put gasket shelac all over them and down in the hole they go in. I also Used a tip off of a tube of rtv and put it on my tube of yamabond,worked good. I put that stuff on everything that had a mating surface and put it on thick. It barely smokes out the right side and hardly any out the left,,,better than my buddies brand new banshee. I want to say thanx to everyone who helped me get this figured out, I owe you one. GREAT SITE! Quote Link to comment Share on other sites More sharing options...
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