|
|
Post by drawkward on Mar 6, 2010 17:53:53 GMT -5
Symptoms:
Bogging at certain throttle levels (Mix screw settings?)
Scooter revs up randomly at stop lights (Air leak? Is my RTV Sealant Giving out?)
And this one just happened after an exhaust bolt fell out on the way home: It wouldn't turn off when I turned the key (I have no kill switch). It took my a couple of tries.
The last one is really strange. I don't see how a missing exhaust bolt would keep it running even with the key off. What do you guys think?
PS: Do you guys happen to know the bolt length, pitch, and thread size for the exhaust? I could just take the remaining bolt off at the store, but I wanted to see if you guys happen to know. Oh and it's the bolt that goes onto the cylinder, not the frame or muffler bolt.
|
|
|
|
Post by 90GTVert on Mar 6, 2010 23:31:50 GMT -5
It really sounds like you've got a vacuum leak somewhere. Check everything over. If you don't see anything obvious, try spraying carb cleaner around the carb/intake/reeds and see if the engine reacts.
The header bolts should be M6 x 1.0. Not sure of the length... 15-20mm? A lot of things on your scooter should use M6 x 1.0 bolts, so it's never a bad idea to keep spares around. For example, CVT cover bolts, header bolts, seat bolts, mounting bolts of all sorts.
|
|
|
|
Post by 2strokd on Mar 7, 2010 7:44:34 GMT -5
I think Brents right, sounds like a vac leak somewere?! Hope not, but one reason it would have kept running is if it were real hot! The sparkplug will act like a glow plug if it gets hot enough and it will continue to run even with the ignition off. Are you running an BR8?
I would check for leaks for sure. Hope ya get it figured out.
|
|
|
|
Post by drawkward on Mar 7, 2010 9:00:00 GMT -5
Shit. Ok I'm taking the engine off again (Tech section, here I come) and resealing. I'm going to need to get some new gaskets so I don't have to keep doing this. It's the only thing I can think of with the vacuum leak.
The glow plug makes sense since my fan cover is a little loose. Hope no damage was done. If so, then oh well. A perfect excuse for to go ahead and buy the BBK. I'll let you know about the plug a little later.
I'm also going to buy a bunch of spares since they all use the same size. Thanks for the tip. I've already got some blue thread locker, just haven't gotten around to going through and locking all the screws and bolts. I've got all day so I suppose I'll go ahead and do that. I just got a couple new jobs (waiter at Uno's, and a cook at Silver Diner ;D), so now's the time that I reallllly need the scoot to be at it's best. Before it was just for fun and convenience, now it's important to me. Don't want it dropping bolts all over town.
|
|
|
|
Post by drawkward on Mar 7, 2010 10:12:52 GMT -5
Ok I got it apart. (The tech section really makes it a quick and easy job. Got it off in about 30 minutes. Thanks Brent). It was definitely overheating. I took a picture of it before right after I lifted the scooter from the engine assembly. Multiple factors contributing to the overheating. 1. A hole in the fan cover itself 2. Fan cover was not seated properly 3. Engine shroud was not seated properly 4. Fan is missing blades 5. Engine shroud has a hole melted in it from the head, and the head has plastic melted onto it. As for the vacuum leak... I am debating removing the head and cylinder. I want the BBK... and I think I am about to order one, but I don't know when I'll have a chance to do the work. If I am going to order one, I think the seal would hold up until then. I've switch image hosting sites, due to the fact that imgur is now charging to keep more than 75 images on file. Moved over to photobucket, and I really like their setup. Here is a link to an album containing some pictures of the various problems I'm having. I tried getting some of the seal, and the oil around it, but they didn't come out too well. I'm not sure if all the oil is from the exhaust being loose, or from the seal. s844.photobucket.com/albums/ab4/koohnav/Scooter%20Overheat%20-%20March%202010/Edit: Got the OK from gram's (I just moved in with her, and she's watching my money spending) to get the BBK. Going to order it up today. Just wanted to check with you guys to see if you happen to know of a good cheap kit (cheaper than autotech's $135 kit with free shipping). I've got a 10mm pin. Thanks for any and all help. |
|
|
|
Post by 90GTVert on Mar 7, 2010 10:38:07 GMT -5
It looks like you've got a serious base gasket leak from those pics. That's a lot of residue that even looks wet around the base gasket. I don't think it's just form the exhaust because it goes way up on the cylinder. I'm sure a good bit of the stuff at the bottom is from the exhaust though. Now would be a good time to have a leakdown tester like 2strokd made... 49ccscoot.proboards.com/index.cgi?board=yamajog&action=display&thread=425If it were mine I'd install the exhaust bolt, replace the fan, repair/replace the shrouds, affix the shrouds properly, and either make a tester and check for leaks or just pull the cylinder off and re-seal it. If you wanted to use a gasket but don't wanna wait for one to be delivered, you can get gasket paper that is resistant to gas and oil from auto parts stores and cut your own. It's a bit of a pain, but sometimes it's better than waiting a week or two for a precut gasket. or you could just try RTV. You could use black duct tape to seal everything up and cover holes on the shrouds if you don't wanna put the cash out at the moment. I've been using Gorilla Tape on mine. It's a really strong version of duct tape that's black. Apply it neatly and it isn't terrible to look at. Not as nice as new parts, but cheap. I seal the seams with it too. |
|
|
|
Post by Reign on Mar 7, 2010 11:25:07 GMT -5
Damn, thats a shame that you ruined that fan. That was one of the first things I stole from my RX8 engine to put on my Triton, because it blew like 3X the air of the stock fan. If you do decide to get a BBK. you're gonna want to get a "performance" fan from say, partsforscooters. You asked me if I had any spare fans, and I do, but they're all stock fans with small fins. You're going to have just as much of an overheat issue after switching to a BBK with one of my fans as you have with your current fan. www.partsforscooters.com/169-142_minarelli_turbo_fan_2?sc=9&category=118197 |
|
|
|
Post by Reign on Mar 7, 2010 13:24:29 GMT -5
Hey, just a side note. I just happened to remember that I was having the same issue with my Triton back when I was only using 1 bolt on my exhaust. The exhaust ended up coming loose and sliding back, which gave me less power, and caused my engine to rev up at stop lights, and it also caused my engine to keep moving after letting off the throttle. I'm sure overheating is part of your problem, but I'll bet that exhaust bolt is the other part.
|
|
|
|
Post by drawkward on Mar 7, 2010 13:39:56 GMT -5
That makes sense. I'm sure it isn't helping. As long as it's running, and I can get to work for now, then it's going to stay like that. Here's the new tape job. Didn't buy new tape, just used the grey duct tape I had already bought, seeing as this is just temporary anyways.   So, yeah. I didn't lose the bolt. It broke off in the head. Must have been overheating REALLY bad. Couldn't get a good picture of the bolt, but you can imagine. I don't have my extractor kit with me, so it's going to stay like that, until I get my new cylinder kit. Here's a picture of the blown exhaust gasket that I removed. The scooter is extremely loud now. Video after the pictures. (PS I haven't tuned it yet, and I am actually running the mix screw in a little bit, because the plug looked like this):  Exhaust gasket:   |
|
|
|
Post by Reign on Mar 7, 2010 13:58:34 GMT -5
Yep, sounds just like mine when that exhaust slid back and opened up the exhaust port. It had been leaking since I installed the pipe, and I was wondering why the pipe actually DECREASED my performance, and then one day it slid back and got really loud like that. I drove straight home and slid it back and tightened it nice and tight. After that, the performance was substantial, and my engine problems disappeared. PS: That exhaust gasket looks TERRIBLE! I didnt even know it was possible to get it to be that flat  |
|
|
|
Post by drawkward on Mar 7, 2010 17:59:21 GMT -5
Ok so I bit the bullet and bought another extractor kit even though I have one at my old house (can't get there today) and got the broken bolt out. Took the old flattened exhaust gasket, smeared it with RTV silicone, cleaned and globbed a bunch on the header, and a bunch on the pipe. Got it curing right now. Says to give it an hour, so I'm going to do that. I think I know why it broke. Intense heat mixed with a bent bracket. I installed the two header bolts first, then the bracket bolts. Let me tell you, they were WAY off. Took a good amount of bending and rebending to get it right. Now everything fit together easily. Shouldn't have that problem again. Also, I couldn't find my thread locker (must have left it at the old house) so I just dabbed a little silicone on the threads. Hopefully this wasn't a terrible idea, making it completely impossible to removed the bolts. Don't see why it would, as there are nuts out there that have silicone built into them (like on my skateboard) so they don't come loose.
|
|
|
|
Post by 90GTVert on Mar 7, 2010 18:20:03 GMT -5
The RTV should be fine on the bolts. I use RTV to seal studs that protrude into water jackets on my stang and haven't had any issues removing the studs yet.
|
|
|
|
Post by drawkward on Mar 7, 2010 19:33:03 GMT -5
Glad to hear it. After letting the silicone cure for an hour, I started her up and ran the two miles to the store and back without any problems. I didn't notice how much performance I had lost when my exhaust wasn't sealed properly, she's doing excellent now. I actually hit a turn that I had always hit at full throttle before with ease on the way up there that almost made me loose control this time... Gonna have to be careful with the BBK - won't be able to run her pinned all the time.
|
|
|
|
Post by 90GTVert on Mar 7, 2010 23:46:18 GMT -5
Don't wreck it up... you just got it fixed. ;D You'll really be in for a treat with more displacement.
|
|
|
|
Post by 2strokd on Mar 8, 2010 9:33:05 GMT -5
Don't wreck it up... you just got it fixed. ;D You'll really be in for a treat with more displacement. O,yea  ! You get a sweet tune with that BBK and i bet you will be surprised  ! |
|
! You get a sweet tune with that BBK and i bet you will be surprised 
!