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'84 CX650E that is evolving into a GL500
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To swap the coils for testing you need to switch the input wires (pink and yellow) from one side to the other AND switch the output wires that go to the spark plugs from one side to the other. It is unclear from your description whether you did that or not.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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So yes they are from Murray but not directly. If I can't figure it out after trying/checking a few more things I will contact him.
Talk to Murray before making any adjustments.
 

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1981 Honda CX500c "Black Widow"
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Discussion Starter · #63 ·
To swap the coils for testing you need to switch the input wires (pink and yellow) from one side to the other AND switch the output wires that go to the spark plugs from one side to the other. It is unclear from your description whether you did that or not.
I have the coil-on-plugs from Murray so I literally swapped the coils from side to side. Sorry for the confusion.
 

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Discussion Starter · #64 ·
Okay I have some interesting results from swapping the carbs from side to side (left carb is now on the right side of the engine and vise versa). Also, I checked the valves and timing, all is well there. I also checked compression, 125psi out of each cylinder, low but should still be able to run.

Quick recap: left side of engine has been running and right side has not.

With the carbs swapped, I hit the starter, the left side fired right up and idled, no life on the right side (so no change since swapping the carbs). I then swapped the coils from side to side (unclip the coil wires, swap the coil-on-plugs from side to side). I hit the starter and BOTH sides fired up. I got some backfiring and popping from the right side but it was running. I even shifted down into 1st for the first time ever and the rear wheel was spinning (on center stand) so that was awesome to see.
But after about 30 seconds, the right side stopped firing and I couldn't get it to pick up again.

The way I tell if a side is running or not is feeling the air pressure coming out of the exhaust. The left side is very powerful, and the right has just been soft puffs, except for that 30 seconds of glory when both sides were running, both exhausts had powerful air coming out. Also the temp of the exhaust pipes.

Anyone have any ideas or hypothesis??
 

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'84 CX650E that is evolving into a GL500
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That sounds like something you did while swapping things around made it work for a little while and then it want back to the way it was before.
Is there any chance that the fuel line to the right side is kinked or otherwise obstructed?

If fuel is getting to the right carb OK maybe a wire you moved eventually jiggled back so check for a loose connection somewhere between the coil and the CDI.
 

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i know you have sent the carbs in for testing they will be checked cleaned and calibrated when they get her e
but in the future you can also swap the entire carb from one side to the other temporarily for testing
to see if the problem follows the carb
 

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Discussion Starter · #68 ·
Thank you everyone for the suggestions. I went through the harness, especially around the Rae San ignition module and ensured all wires were well connected and insulated. I also tightened down the spark plug tip caps.

After talking with Ray, he advised me to rotate the circuit board on the back of the engine (I think it's called the pulser?) to where the alignment isn't in the middle of the error, 1/2 retarded and 1/2 advanced, but biased to the right cylinder dead on and retarded for the left cylinder...BRAPPPPP.

Just a hair of rotation for that timing circuit and the right cylinder is able to fire up along with the left. I was able to ride my bike for the first time, nearly a year after picking it up with a box of parts. Couldn't get it to idle but as Murray just mentioned, my carbs are on their way to him as of this morning so that should be solved.

A side note, after I got it running, I was finally able to take it to the State patrol shop for a VIN inspection / road worthiness test and although it passed all of the check boxes, the trooper failed it for not having a rear fender, so I will be mocking up a junk one for the time being so I can get the road worthy stamp.
 

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Discussion Starter · #69 ·
Got the carbs back from Murray, slapped them on and the bike runs like new! Starts right up and idle was super easy to set. Thanks a lot Murray.

Went for another test ride, it was awesome, it ran really well and sounded way better that it did before the carbs we're maintenanced.

Unfortunately I have a coolant problem.
Coolant is basically pouring out of the weep hole b/w the mech seal and oil seal. I replaced the mech seal when I had the rear cover off, Shep method I believe, had to flap wheel out half a millimeter for the larger cup. After a 5 minute test ride, the bike was blazing hot, everything was hot, the whole engine, all coolant pipes and tubes, the headers, the intake pipes, and the temp gauge was already on the fat bar on the right half of the meter. My guess is that the problem lies in the replaced mech seal. Any one have any other thoughts?

I think I burped the coolant system, let the cap stay off while I set the idle for a few minutes. Anything I should check before I dig back into the mech seal?
 

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If you fitted a new cup, it wasn't the Shep method.
There's lots that can go wrong in replacing the mech seal, by whatever method. Did you refit the small thrust washer at the splined part of the camshaft? Did you properly torque the dome nut with locktite? Did you soap the ceramic disc or mount it dry? Did you verify that the new seal is seated flush all the way around, so it sits level with the impeller?
 

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Discussion Starter · #71 ·
If you fitted a new cup, it wasn't the Shep method.
There's lots that can go wrong in replacing the mech seal, by whatever method. Did you refit the small thrust washer at the splined part of the camshaft? Did you properly torque the dome nut with locktite? Did you soap the ceramic disc or mount it dry? Did you verify that the new seal is seated flush all the way around, so it sits level with the impeller?
I did refit the small thrust washer over the spline before the impellar.
I properly torqued dome nut with locktite.
I lubed the polo mint.
The new cup is flush mounted.

I was just reading another post and someone with the same problem said they removed the thrust wash on the spline and problem solved. Are you not supposed to reuse it with the new cups?
 

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Discussion Starter · #72 ·
I was just reading another post...

Post #14

I think he is talking about the thick washer that's behind the impellar and not the copper crush washer in front of the impellar under the domr nut. Does that sound right?
 

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You definitely need a thrust washer. In the thread you referenced, he found two.
 

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Regarding the overheating i would revisit the coolant level and possible trapped air. The heat everywhere suggests the thermostat is opening and the coolant is circulating, as much as there is.
The leak; out of round “machining”, partial crushing or crooked cup install, cracked polo mint. A drip might wear in, unlikely a serious leak will. You’ll need to go back in there.
 

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Whet they said^^^

What about that copper crush washer? Did you just us the one that you took out the way it was, did you anneal it and re-use it or did you replace it?

Are you sure enlarging the hole was needed? I believe that they changed the size of the seal's cup some time in '81. Did you actually measure the hole before deciding to open it up? If the hole was originally 27.8mm diameter were you careful not to make it any larger than 28.3mm? Did you use a drill press to ensure that the hole is still straight?

The overheating could be caused by the low coolant level resulting from the coolant exiting the weep hole BUT from my experience when that happens the temp gauge will only indicate a higher than normal temperature until there isn't enough coolant left to keep the thermostat housing full and then the gauge will indicate a cooler than normal engine temperature while the higher temp is obvious to someone on the seat.
Did you replace the thermostat? If so did you put it in the right way up?
Is your fan turning?
Did you mount anything in front of the radiator that could significantly block air flow?
 

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After installing a Davey Pumps sourced mech seal I had an immediate leak because of not annealing the washer under the dome nut, but by undoing the dome nut and liberally applying Three Bond gasket cement it prevented coolant wicking back up the camshaft to the overflow hole and have had no further leaks in 51K kilometres.
 

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Or just remove the dome nut and replace or anneal the crush washer. Less mess the next time you open it.
 

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Discussion Starter · #79 ·
Thank you all for giving me things to check.

I opened the pump cover to inspect everything and it all looked okay so I decided to just try the install one more time but this time with liberal soapy water and another new copper crush washer. I only torqued the dome nut to 8ft-lbs instead of 9 (manual calls 6-9) and verified the impellar turned via the inspection cap on the front.

Got it all back together, fired her up, and not a single drop has come out since. I really think the soapy water did the trick.

Can someone tell me if I am understanding this correctly:
the black portion of the mech seal that is wrapped in the spring seats against the white ceramic disk (polo) and the spring tension is what keeps that seal as the ceramic disk spins with the impellar..?

Anyways I finally had a test ride where nothing went wrong! Besides forgetting to turn the petcock to flow (facepalm). Y'all are the best.
Cheers, and happy Patriot day.
-NG
 

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Yes, the spring keeps the seal in contact with the ceramic disc and accommodates slight misalignment. The turning seal is lubricated by a film of coolant held by capillary action between the surfaces. The soap serves this function on assembly.
 
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