kingston73 wrote:I painted both of them the same time in the same exact way, one of them turned out terrific, and the other bubbled and dryed severely wrinkled, so I have to start that one over again. I don't really understand what I did wrong, or if I just got lucky with the other one.
Re the 7V regulator:
Honda powered the temp and/or fuel gauges on bikes of this era via a regulator that supplies 7V. This was done so that the gauges would have a consistent reading no matter what was going on in the rest of teh electrical system. The system voltage can vary between 9V (idling with the brakes on and the signals flashing) and 14.5V (running at speed). If these gauges were connected directly to the system voltage they would read significantly lower when you are sitting at a corner waiting to turn than while driving.
The 7V regulators were pretty reliable when new, but a lot of them are over 30 years old now and failures do occur. When one fails the output will either become higher than it should or lower than it should. If it goes higher the gauge(s) will read high. If it goes lower (often no output) the gauge(s) will read low.
On models with both temp & fuel gauges it is fairly easy to diagnose - both gauges will do the same thing. On models with only one gauge you need to measure the output of the regulator to know for sure - the gauge itself or the sensor could be faulty. But it is almost always the 7V regulator.
Checking it with a thermometer is a good idea. If the temp is good you can then either get a cheap voltmeter and measure the 7V regulator's output or look for someone with a voltmeter who can measure it for you.
It is also possible to get high output voltage from a good regulator if it's ground connection is faulty.
Personally I would take the money for the thermometer add a bit and buy a multi meter. For like $20 you can get a digital one and you will use it FAR more often. It is invaluable for finding electrical faults (such as your horn) etc etc.
Dennis
Reg has a good description of how to make a 7V regulator on his site. If you need one perhaps someone you know who dabbles in electronics could put one together for you.
Reg: A while ago someone on the Naked GoldWings forum needed a 7V regulator so I posted a link to your site. One of the fellows did some experimenting and now several of your regulators are on GoldWings.
kingston73 wrote:If it does read 7 volts, the next most likely thing will be what....thermostat?
If you can put your hand on the rocker cover and hold it there for a few seconds it probably isn't overheating. If it feels as hot as the headers it is overheating. This is just a crude test, but it should give you an idea.
If the engine isn't overheated and the gauge reads high the only possibilities are the 7V regulator, the gauge and the sensor. Didn't you say that the connections to the 7V regulator were in bad shape? As I mentioned before, if the green wire is not grounded properly the regulator won't regulate, so I would take a close look at that first.
If you haven't replaced the thermostat & rad cap it might not solve the problem but it is proabaly a good idea anyway. Have a look at my article about Cooling System Servicing
I left it idle with the cap off for about 5 minutes and watched the coolant, it never started to flow and the bottom left coolant pipe stayed cool.
I don't remember ever seeing the coolant moving in a rad that way either. All I have ever seen is the coolant level go down a bit when the engine is revved, and the engine must be fully warmed up and the thermostat open.
Some engines take a lot longer than 5 minutes to warm up at idle. You should increase the RPM and vary the throttle to get it to warm up. If you keep your hand on the transfer pipe you will feel it suddenly get warmer when the thermostat opens.
I put the cap on and drove it around the block and watched as the needle crept up into the red. The bottom left pipe felt hot when I came back, but couldn't that just be engine heat transfer?
Most likely the pipe was hot because hot coolant was flowing through it. Did the rad also feel warm? If the thermostat isn't opening the rad will be cool to the touch when the engine is warmed up or even too hot.
Is it supposed to make any noise after you stop it, as its cooling off? I could hear very faint tick, tick noises, the same kind a car with an aluminum block makes.
Sometimes you can hear the exhaust ticking, but there shouldn't be any sound from the engine.
On another note, what would explain my odometer working but not my speedometer? I thought they were driven off the same cable and assumed if one worked the other would too, but when I drove it today it was telling me I was going 15 mph at a stop, and I had my wife drive behind me and she said at one point I was doing 35 and my speedo said 20. Does the plastic retaining ring on the fender affect it? I broke it and the cable isn't inside it any more.
If the plastic ring is missing or broken the bike is shifted outside the normal space-time continuum and appears to those in normal space-time to be travelling much faster than it actually is. ;-{)
(Actually, all it does is keep the cable from flopping around.)
It sounds like your speedo has died. The odometers (main & trip) are driven by gears but the speedometer needle is pulled around the dial by magnets. Sometimes the bearings in the speedo fail or dirt gets into them and stops it from working properly and sometimes they just wear out. Sometimes the needle comes loose on it's shaft and you can get all sorts of strange & eratic readings while the odometers both continue to work normally.
kingston73 wrote:Where did the coolant go?
kingston73 wrote:I'm doing what I should have done originally and taking the rad off, flushing it completely, and putting a new t-stat in. Then I'll put it all together again, put new coolant in, check the volts with my multimeter, and go from there.
Don't stop there - put in a new rad cap and hoses too.
Don't forget the 2 drain screws behind the rad. They are just 6mm bolts (10mm wrench) with aluminum crush washers behind them. Use a torque wrench when you replace them - those washers are really easy to destroy if you tighten the bolts normally.
In case you missed it the first time: Have a look at my article about Cooling System Servicing.
BTW: You don't need to have the engine running to check the 7V regulator.
Hi Bob,
The more I read the forum - the more I learn - as I've not had nor ever used a torque wrench with all the bikes I've worked on ...... and never had a problem with cracking anything but my knuckles once in a while .... but now thinking about totally stripping everything on my CX and rebuild from scratch to specs (might as well as I only have the wheels to take off <grin> ........ hence: I've been checking around - and believe the best would be a 3/8" with 5 to 80 ft. lb. wrench ..... What you think ????
Speaking of which - I can't seem to find and torque settings on the front and back engine cover bolts - (2 sizes) - ?????
Cheers, n' Happy Trails ahead,
Bryan
Sounds to me more like a faulty thermostat or worst still a blown head gasket - but you haven't said anything about milky mulch in your oil - so keep your fingers crossed - and check your thermostat - the valve should open at around 180 degrees F (or 82 degrees C) ...... and overall agree, this is a great time to "take your time and get to know your bike- before you start riding - especially for any long runs - as you never know when a minor problem (with a quick fix) can save a lot of time and money .....
Cheers, n' Best of Luck,
'78 CX500 (still in 1,000 pieces in my kitchen)
By the way - as you've mainly be talking about the rad - no harm in flushing it and replacing the hoses and rad cap - But the thermostat is not in the rad cap - but rather in the housing behind the fan with the two pipes going to each cylinder ..... and it's simple to check - with just a thermometer and placed in a pot of boiling water ....
Cheers, n' Happy Trails Ahead,
Yet, an afterthought - as I read your posts - the antifreeze seems to be going somewhere rather quickly - so I doubt it's evaporating and must be going through your system and out somewhere - hence: possibly the water pump mechanical seal ..... Does the back of your engine have a brown stain or worse wet grunge ????
I replaced the mechanical seal 3 years ago with my new stator - and it still looks good - but will be checking it again, once I get it back together ...... as it's one of the three major CX engine out "triple bypass" syndromes ...
Otherwise, be thankful - as it's probably one of the easiest engines to work on - especially for a beginner - as I learned on ol' hogs n' about the same time learned a lot of new curse words <grin> !!!!
Bryan wrote: I've not had nor ever used a torque wrench with all the bikes I've worked on ...... and never had a problem with cracking anything but my knuckles once in a while .... but now thinking about totally stripping everything on my CX and rebuild from scratch to specs (might as well as I only have the wheels to take off <grin> ........ hence: I've been checking around - and believe the best would be a 3/8" with 5 to 80 ft. lb. wrench ..... What you think ???? Speaking of which - I can't seem to find and torque settings on the front and back engine cover bolts - (2 sizes) - ?????
I used to feel pretty much the same way about torque wrenches - I only used mine for tightening heads. Then one day I noticed a noise from the back of the engine (this was when I had the 650 in my GL500) and when I looked down I saw all of the coolant running down the side of the engine. When I got home and removed the water pump cover I discovered that the nut that I had tightened with a regular wrench had come loose and the noise was the impeller rubbing on the inside of the cover. I tightened it with the torque wrench and it didn't come loose again. Since then I use the torque wrench a lot more.
When I squashed the aluminum washers I was only using a hand wrench. You can imagine what I could have done with a ratchet.
What kind of torque wrench? Well, first make sure you get one that is designed to read in metric units. The specs in all of the manuals were written by engineers who worked in metric and any imperial units are translations so it's better to work in the same units the engineers did. The torque values in the manual range from 1.5-3.0 N-m for the rad drain bolt up to 90-120 N-m for the steering stem nut and the swingarm pivot lock nut. I found this info on p. 1-4 of the GL500/650 FSM. Similar info is in the CX500 FSM, but I think they use kg-m there. (10 N-m = 1 Kg-m)
Metric units are also a lot easier to think in if you haven't been corrupted by learning something in imperial units. It's a lot easier to figure things out in a system that always uses 10 than in one one that uses 12 sometimes, 3 other times, occasionally 4 and even 5 in one case. My advice is to forget about imperial units entirely when working on bikes. And the rest of the time too if you can manage it.
A 3/8" drive is fine, but I also have a 1/4" drive torque wrench - I couldn't find a 3/8" drive 8mm socket for those engine cover bolts and I didn't like using the 3/8" drive with an adaptor for a 1/4" drive 8mm socket. Oh, and since those are 6mm flange bolts, they should be torqued to 10-14 N-m (1.0-1.4 Kg-m). The 8mm flange bolts need 24-30 N-m (2.4-3.0 Kg-m).
Tip: If you have a cordless drill with a clutch for driving screws you can put an adaptor in the chuck for an 8mm socket, set the clutch to a lower torque setting and use it to drive them in to a fairly uniform starting torque before using the torque wrench to tighten them. Don't forget that you should always torque bolts in several stages and always tighten them in a criss-crossing pattern to minimise warping.
BTW: I know what you mean about having the whole bike apart. This is what my 650 looked like on Sept.30 06.
A week later (Oct.6) after the safety inspection
2 weeks after that (Oct.19) when it was on the road & pretty much ready for winter
kingston73 wrote:OK, so I just took some readings, the blue/green wire out the t-stat read about 9.5, the yellow wire in the headlight from the 7v reg. read about 10.1, so does that, along with the temp gauge getting into the red within 5-10 minutes, all add up to a blown regulator and not an overheating issue?
Bryan wrote:Sounds to me more like a faulty thermostat or worst still a blown head gasket
I have to disagree with Bryan here. If you are getting any voltage other than 7V at the yellow wire the 7V regulator is your prime suspect.
A bit of terminology clarification:
Thermostat: A thermomechanical device that prevents coolant from flowing from the engine to the rad until the engine has warmed up and opens a valve to allow coolant to flow when the engine has warmed up. It is located inside the thermostat housing on top of the engine between the cylinders.
Temperature sensor (AKA temp sensor)(AKA Temp gauge sender): A thermoelectric device that changes resistance depending on temperature. It is connected in series between the temperature gauge and ground so that the gauge's reading changes depending on the coolant temperature (& the sensor's resistance). It is located in the rear side of the thermostat housing.
In other words, the blue/green wire goes to the temp sensor, not the thermostat. This is an important distinction, as each one functions entirely separately from the other and the thermostat is a standard automotive part that you can get fairly cheaply almost anywwhere except for Honda bike dealers and should be replaced every few years, while the temp sensor is only available from Honda bike dealers and almost never needs replacing.
Before I started looking for a replacement 7V regulator, I would try measuring the voltage on the green wire at the 7V reg. with respect to a known good ground connection (battery negative is the best, but if the lead won't reach you may have to use something solidly connected to the bike's frame or the engine block). If you get a reading of about 3V there you have a bad ground connection to the 7V reg and this can be remedied by cleaning the connections of (worst case) replacing the green wire. If the reading at the green wire is 0V and you still have 10V at the yellow wire you need a regulator.
Re the lower level in the overflow after the engine has been fully warmed up: If there is any air in the cooling system it will make it's way to the rad after the engine has been run for a while (idling doesn't count). It will rise to the top of the rad and be expelled to the overflow tank when the pressure in the cooling system increases enough to open the valve in the cap and when the engine cools and the pressure decreases coolant from the overflow will be drawn into the rad. In other words, this is perfectly normal as long as it doesn't happen the second time you run the engine. BTW: The level in the overflow tank should be at or above the lower line when the engine is cold and somewhere near the upper line when the engine is warmed up. If you have too much in the tank to start with any excess will come out of the hose connected to the top of the tank when the engine is warmed up and coolant from the rad flows into the overflow. Once the coolant in the overflow tank has settled on a level it should stay about the same when checked at a given engine temp, so it sounds like yours is OK.
Re sound of bad camchain: When the camchain guide in my GL500 failed and the chain went really loose it sounded like a diesel pickup idling on a cold morning at idle (the sound echoed up inside the fairing so it sounded like it was coming from the front of the engine), but sounded normal when on the road under load.
These engines have overhead valves operated by rockers and pushrods. This tends to be a fairly noisy valve train, especially since the heads stick out on either side of the tank so they are fairly close to your ears and there is nothing to block the sound. It always takes me a few days to get used to it when I change to/from my GoldWing with it's relatively quiet belt driven overhead cams in heads at ankle level.
Thanks Bob for the info - as usual you have answered all my questions about the torque wrench - and must admit that your more likely right about the regulator - as I was just putting my 2 cents worth into the conversation - as mainly check everything that could possibly relate - thereby easing the mind and overall a process of elimination ........
Otherwise, I also admit that I was pickled drunk last night - and going in the same direction tonight - but sobeit - it's my life - and I helped a friend with her groceries this afternoon - and brought home some more alcohol for me n' my doggie <smiles> .......
So life is good n' about ready to turn on some ol' Hank n' Jimmy .......
Cheers, n' remember to keep the wind at your back - as ol' farts stink <LOL> !!!!
God Bless,
Bryan ------------------------------------------------------------------------------------