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07-22-2008, 5:57 PM Anonymous Bike won't run after stator replacement! Took my CX500T into the shop for a stator replacement as I did not feel comfortable with my skill for pulling the motor. In any case the stator is replaced but the bike barely idles and will not take any load. Mechanic is now afraid of it and is offering no help (but will take my money for the Stator job) Sooo... Checked the computer and LOTs of codes. Every combination of 0,1 &2. I have the shop manual and this tells me that 6 of the sensors (p1, P2, PB, etc..) are open or grounded. Bike ran well when I brought it in (except for the stator) I looked at the electric schematic and discovered that of the 6 sensors with problems the ALL share a common blue wire that goes back to the computer. Tomorrow i will check this wire for continuity to the computer. Anyone ever see this before? Any thoughts?

07-24-2008, 4:17 PM Anonymous Re: Bike won't run after stator replacement! Bike still doesn't run and my theory above about the common sensor wire did not pan out. I tested the power in to the sensors and got the 4.75 - 5.25 that the manual specifies. I then jumpered power to the sensor and read the expected voltage out. I am at a loss - How can the ECU fire off codes if the sensors are responding? Book says the ECU only codes if the cicuit is open or grounded. The mechanic suggested I look at the coils and one was some what corroded. Also one of the ingnition wires was carbonned up on the end. The coils read the expected primary and secondary resistance. Tried to clean up the corrosion a bit and then put all back together - No better result. Anything anyone might suggest would be helpful. Also, where might I get new coils and wires? While I doubt this is the problem it couldn't hurt.

07-24-2008, 5:05 PM ChopperCharles Joined on 02-18-2006 Chapel Hill, NC Posts 432 Re: Bike won't run after stator replacement! Inspect the wiring harness from one end to the other. It's a fair bet that a wire got pinched between something when the engine was reinstalled. Did that myself once on an old Virago... stumped why it ran the day before but wouldn't start now. I'm not quite sure about how the Turbo ignition system works, but the CX500's and GL500's have pickups with a mechanical advance. If the mechanical advance is bolted on wrong, the cylinders will fire at the wrong time. The bike may idle if you're lucky. Finally, check the fuel pressure. Your pump may not be working, or you may have a blockage in the system. ...but really, my bank is on wiring harness or improperly installed component. Charles.   87 TW200 84 V65 Magna (x2) 75 GL1000 (in pieces) 78 CB550K 82 VT500C Shadow Location: Durham, NC    Report

07-24-2008, 6:50 PM George in Indiana Joined on 03-03-2006 Posts 322 Re: Bike won't run after stator replacement! Are you sure you're reading the LEDs correctly? I've never heard of every code showing up like that. He may have switched some connectors as there are a few that are keyed the same. The fuel gauge sendng unit connector will attach to something else (can't remember), does your fuel gauge work? There are also clear and yellow connectors that appear the same with age and can be swapped. Hopefully he didn't short something out and damage the ECU. More than likely though it's going to be something very simple. Posting more details on how the codes come up (order, only when engine reved ect.) would be helpful. Also where are you located? CX500 TURBO CX650 TURBO '86 Honda Elite 150 Deluxe '04 GSX1300R Hayabusa    Report

07-24-2008, 6:53 PM George in Indiana Joined on 03-03-2006 Posts 322 Re: Bike won't run after stator replacement! Oh yeah, are all those sensors vacuum/pressure related? You may have a disconnected hose. CX500 TURBO CX650 TURBO '86 Honda Elite 150 Deluxe '04 GSX1300R Hayabusa    Report

07-24-2008, 11:13 PM Rob-Davis Joined on 03-05-2006 Telford, Shropshire, UK Posts 59 Re: Bike won't run after stator replacement! I had exactly the same problem after a rebuild and new stator, and despite all manner of excellent advice, never got to the bottom of it and in the end, as I was unwilling to invest any more time and money, I broke the bike for spares.  The symptoms were simply that it would not idle on one cylinder, although there were no computer LED faults and everything I checked was exactly as it should have been.  It ran reasonably well after 2,100 rpm. In fact the only thing slightly wrong which I found at the end of the dismantling was that the copper turbo-to-exhaust downpipe gasket was leaking slightly.  Anyway the wretched thing is making its way out of my life and frankly I'm glad.  It was great fun to ride but a total nightmare to own. =================== Rob Davis Telford, Shropshire UK http://www.cx500.webhop.org now leaving the CX world Skype : rob_davis_cx500    Report

07-25-2008, 3:42 AM Steve Joined on 07-25-2008 Posts 3 Re: Bike won't run after stator replacement! Thanks everyone for the replies. I live in uppstate NY not far from Albany. Details: Bike ran "fine" last year with the exception of a warm engine "stumble" at idle. It has done that for years so I accept it as normal. Left me stranded last fall for the first time ever in 20 years. Dead battery and no charging. With some basic mechanical skills but really little time, I deciced to have a mechanic do the stator. Found a guy who claimed he was a honda mechanic in the day and could change the stator in his sleep. Dropped the bike off in Aprill and he called early this week to say it was done but not running right AND the bike was a nightmare to work on and doesen't want to touch it. Said I could come in and look at it. He also told me tha he found some shavings on the oil drain plug and that the turbo shaft would wiggle. Told me it spun fin but he feels the turbo bushings were shot. I took this at face value. Could be true on an old bike but I had no driveability issues or turbo issues last year or ever for that matter. Hmmmm. What I found was a bike that would start hard but would idle almost if nothing were wrong. Fuel light on and these codes - 0, 1, 01, 2, 12. But NOT 02 (as I first thought) If you touch the throttle to rev the engine everything dies immediately. If you EVER so slowly open the throttly you can get some revs 3-4000 or so be fore she dies. Absolutely can put no load on the engine. I was told that after reasembly he rode it 1/2 mile down the street and this did not star until he was on his way back. I was also told that he had a very dard time to start it but found by coincidence that if he just "touched" the kill switch the bike would start. I have the shop manual. It tells me the stop switch connects IG & Batt2. when you turn it off and on you hear the fuel pump. The switch works, but the mechanic felt there may have been some weird resitance causing a problem. To keep him happy I jumpered IG directly to the Battery + and we started the bike - no change. Next he says it must be ignition problems. I dig into the coils and ignition wire and find one coil with corrosion ant that wire very black were it connects into the coil. This is on the left, Right seems to look fine. The coil ohms out fine, but it is "touchy" so I bead blast the connection. and trim back the wire a tiny bit. Not a great but without a new coil and plug wire best I could do. Also this could explain the hot idle stumble over the past several years. A this point he wants me to find new coils and wires. Can't seem to find these any where so assistance would be helpful here. Now for the ECU and th codes. I originally thought 02 was lighting also and the common denominator was a Gr/Bu common wire. I checked continuity back to the ECU harness connector (pin 3) and it was fine. I next picked one of the P sensors to test (think P2) and found correct voltage to the sensor and correct voltage reading back. By the way I tested these at the connecter located on the right side of the bike just above the tool area. I did not check all the coded sensors, but if one was working that blew my common wire theory. Also, the shop manual say codes are thrown if the circuit is open or closed, not if the reading is simply unexpected. Also while there are codes that indicate disconnected vaccum lines, thes codes were not present. So here I am, with a bike that does not run. I will have to borrow a trailer and trailer it home (the shop is about 50 miles from my house. I have paid $400 up front on a job that was quoted at $875 and I know he wants the rest of his money. Any thoughts on the ethics here? He did spend the time, but now he is leaving me flat with a non functioning bike. Also taking 3+ months on a 12 hour job is also annoying. Again, I appreciat thoughts, suggestions, and pointing me in the direction of anyone who might help.    Report

07-25-2008, 4:45 AM CXTURBOBOOST Joined on 05-03-2007 Posts 100 Re: Bike won't run after stator replacement! Tell him you are coming to get the bike and won't pay a dime more until you determine if the current issues were caused by him. If they are unrelated in the end, you should pay him what you agreed upon. (His rate was a bit high if you ask me--Unless it included the stator cost and other parts associated with R/R) If he caused the current issues, you will be asking him for your down payment back! If he gets fussy, tell him you will call the Sheriff....    Report

07-25-2008, 7:15 AM Anonymous Re: Bike won't run after stator replacement! Thanks for the ethics suggestion - I was thinking along the same lines. The $400 up front covered parts + a bit extra. In anycase I do not expect to see that refunded. If he were willing to continue working on the bike I would be happy to pay the balance and maybe even an additional $500 - $600 in labor + Parts. Problem is he sees it as a white elephant and wants to spend time on oil changes, etc. Ultimately I went to him to pay for his expertice on the turbo just so I wouldn't have to pay time and materials for someone to stumble around. Back to the problem - What is the likelyhood of the ECU being the culprit? I know it worked and was not coding (at least not enough to trigger the Fuel light) when I rode the bike the 50 mile to the shop in April. I keep coming back to the thought that a computer will only do as it is programmed and if the manual says these codes indicate open or closed sensor circuits and I KNOW they are not open or closed, then how is that happening? My mechanic went as far as to suggest that maybe the computer knows the Turbo bearings are shot and it won't let the bike run that way. I guess a nice thought, but this 1982 "computer" is barely more than a calculator and nothing in the manual suggests that a code means anything more than a bad sensor. So the next thought is there any facility I might take this to in upstate New York that would have spare parts laying around (ecu, ignition module, coil, etc) to try for a process of elimination?

07-25-2008, 3:03 PM CXTURBOBOOST Joined on 05-03-2007 Posts 100 Re: Bike won't run after stator replacement! Try a different ECU... Then start at squre one. Go through everything per the service manual. If you don't have one, buy one. They are very good and detailed. I can help if you need further assistance. Check for a ground that isn't hooked up.... Pete    Report

07-25-2008, 4:12 PM George in Indiana Joined on 03-03-2006 Posts 322 Re: Bike won't run after stator replacement! At this point I agree with Pete on the ECU. About 2 years ago the one in my 650T up and died while out riding. First it went into limp home mode and got me a block before it died completely as I rolled into a gas station parking lot. It kept reporting a bad sensor (P2 I think), after confirming the sensor was good and swapping in a known good spare I traced the wiring back to the ECU pin and everything was fine. I then opened the ECU and traced it back to a prom. The back of the ECU metal housing was a bit grungy and when opened I noticed a good amount of water damage to the boards. The ECU sits in its plastic box at an angle. I think somewhere down the line the harness connector was not sealed good and water got into that box from washing or just condensation on the metal housing from weather changes. Either way water got in there and there is no drain hole in that plastic housing. Eventually water made it past the ECU's gaskets and to the boards. I'd recommend buying another ECU and even if that isn't the problem, there's no harm in having a spare. Plus you could always sell it later, considering the rarity it's money in the bank. :) CX500 TURBO CX650 TURBO '86 Honda Elite 150 Deluxe '04 GSX1300R Hayabusa    Report

07-25-2008, 4:19 PM George in Indiana Joined on 03-03-2006 Posts 322 Re: Bike won't run after stator replacement! Also with all the codes you're seeing, open up that ECU and make sure a ribbon cable connecting the boards didn't pop off. You'll be amazed at what's in there. When you factor in all the mapping for boost, it probably does more than any modern bike's ECU. Only thing it lacks is memory after the bike is turned off. And eventhough it's an amazing little computer, it doesn't know if the turbo bearings are bad. :) Your mechanic's statement made me laugh and scared me a little at the same time. :) CX500 TURBO CX650 TURBO '86 Honda Elite 150 Deluxe '04 GSX1300R Hayabusa    Report

07-25-2008, 5:19 PM Steve Joined on 07-25-2008 Posts 3 Re: Bike won't run after stator replacement! I think buying a known working ECU is good advice. There were a couple on EBAY just a few days ago. Now there only seems to be one from a guy asking pretty high prices for his parts. Anyone know where there is an ECU looking for a new home? By the way, yes I have the shop manual. A good resource - but makes this situation all the more confusing. I also have it on PDF if anyone else needs it i would be happy to send it along. I will look for ground issues too. From what I saw it looks like all wiring is put back and right. Something is wrong though so I will need to take the time and go over her piece by piece. I have read the other thread and I'll tell you all right now this is the only bike I want - had it my entire adult life and will not sell her off in pieces...    Report

07-28-2008, 1:22 PM Sidecar Bob Joined on 03-02-2006 Kawartha Lakes, Ontario Posts 967 Re: Bike won't run after stator replacement! Steve, This is Don in Oz on Bob's computer.  Has your bike ever been guilty of ingesting any of the airfilter foam-plastic? This can give the turbo compressor a hard time, but it will pass in small bits.  You do have the coarse gauze filter at the bottom of your airbox, I hope. The foam bits may have lodged in the air orifices that supply the various air hoses which connect with the pressure sensors. The metering orifices are in the back of the inlet manifold/surge tank assembly. Also check you have the right tube connected to the right sensor - one of the turbos I was asked to troubleshoot had two hoses interchanged. I have experienced many turbochargers that have what you would think are very loose in the bearings - remember there are TWO oil-filled bearings one inside the other at each end of a shaft that only has about 1" between the bearings - expect to feel larger clearances than for a normal single oil-filled bearing.  Feeling the "clearance" at the exhaust-end of the rotor is at least 3/4" overhang from the nearest bearing. The ECU doesn't even measure fuel pressure to give the fuel system warning. Have you checked the cleanliness of the small conical fuel filter at the inlet of the fuel pump? It's NOT mentioned in the handbook, but sometimes comes out INSIDE the inlet tube when you pull that tube off the inlet spiggot of the fuel pump. Have you measured the fuel rail pressure - is it 36psi with the engine stopped?  Does it drop to about 30 psi when you idle the engine?   Does it increase to up to at least 50 psi when you ride and boost solidly? The fuel pressure regulator is NOT easy to find a replacement for - many regulators are only suitable for normally aspirated engines, and will not stand positive pressure on their diaphragms - i.e. normally aspirated EFI cars. I'll be home in Oz in about 5 weeks - may be able to give you some more ideas as I get stuck into re-assembling a CX500TC from a trailer-load of bits.   GX650EI + Velorex 700 (winter), '83 GL1000 (summer) '84 CB750SC Nighthawk (died - anyone need parts?)    Report

07-29-2008, 7:06 AM Sidecar Bob Joined on 03-02-2006 Kawartha Lakes, Ontario Posts 967 Re: Bike won't run after stator replacement! Don in Oz again.  The statement that the bearings are at the ends of the shaft is not correct, at all, of course - they are BOTH inboard of the compressor and turbine, but are at either end of the support portion of the turbocharger body where the oil  cools and lubricates them.  The main reason to get a turbocharger rotor worked-over is when the radial oil seal at the exhaust end starts leaking oil into the exhaust scroll.     Then you consider oil leaking into the intake compressor from the same lube. source ( but this is not so likely due to there being  air pressure on the other side of this "seal" which increases as the potential boost is increasing).  So the boost pressure works against the oil "pressure" from its supply side. After you have considered these two possibilties, only THEN do you need to think about the concentric sleeve bearings - they usually last much better than most people think. GX650EI + Velorex 700 (winter), '83 GL1000 (summer) '84 CB750SC Nighthawk (died - anyone need parts?)    Report

08-01-2008, 11:46 AM Steve Joined on 07-25-2008 Posts 3 Re: Bike won't run after stator replacement! Thanks for the specific suggestions, Don. I know I have a bunch of work to do and that there are no short cuts, but the insight you and others are offering help me to get my head around this.... So bike came back (on the trailer) yesterday. Mechanic was not too thrilled over what I figured I owed him. That bridge is burned, but frankly he was not the resource I thought he was. I thought I was buying expertice and familiartity with the CX500T, turns out I simply hired a wrench turner who prefers to do oil changes... Well the bike is home and I will set aside some time to start the investigation. At this point it will not even idle. Got it to idle briefly before I left the shop, but only once fore a few seconds. Subsequent tries were no good. I think I need to get to REAL basics - Air fuel & Spark. If I believe the mechanic, he told me the bike ran fine for a 1/4 mile and then started having problems. These problems SEEM to be getting worse as bike wont even start now. I will start by confirming spark at the plugs and then dive into fuel. There is one thing I am not clear on and if anyone could provide the answer I would very much appreciate it - it is about the codes that the ECU is reporting. Does a code mean that there could be problems in a specific system, OR does it mean it believes the sensor circuit is open and/or shorted wire? Subsequent trouble shooting procedures ask about the codes and refer to the chart, but then are some what ambiguous -like "repair or replace faulty parts" Does this specifically mean check the sensor and the wiring for open or short circuits? That is how I am understanding it, but the problem arises because I checked the P2 input/output, the wiring continuity to the ECU conector and all was as expected...    Report

08-07-2008, 4:25 PM Gene McCall Joined on 03-02-2006 Murfreesboro Posts 590 Re: Bike won't run after stator replacement! Steve,  Her's one that you will probably never hear again.  One of the turbos I bought - real cheap, but with new plastics - had ceased to idle/run.   It gave black smoke from the muffler if it ever fired for a few seconds - with the throttle held at about 25%. I ended up taking the right-hand rocker cover off - I had determined that the RH cylinder was the dead one. Imagine my surprise when I discovered that neither of the exhaust valves opened when you turned the motor over.- the pushrod was not sitting in the cup of the rocker.   On further investigation,  the pushrod seemed too short for the job.   Broken off sub-rocker head?   No.  After taking the RH head off, I found that the previous owner/mechanic had omitted to install the sub-rocker shaft locking screw, and the shaft had backed out until the exhaust subrocker actually fell off the shaft - no mechanical damage whatsoever, as the engine stops before the shaft interferes with the camshaft sprocket. AND the mechanic had left the LH locking bolt out, also, necessitating  removing the LH head also. After tidying up this matter., the whole bike runs as if new, and if the subrocker IS damaged, then a normal CX500 subrocker is identical - there are two different types, but dimensionally, they operate the same.  Steve, This is Don in Oz using Gene's log-in - we're still on our Odyssey around USA and Canada, with over 13,100 miles added to the speedo since we left Murfreesboro on 7 June. I didn't get this old by being timid, just not being stupid!    Report

08-13-2008, 2:02 PM Anonymous Re: Bike won't run after stator replacement! any update yet?

09-01-2008, 12:13 PM Don in Oz Joined on 03-10-2006 Melbourne, Australia Posts 307 Re: Bike won't run after stator replacement! Steve, I'm back in Oz now - any advances with the problem?    Report

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