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'82 GL500 Interstate
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Discussion Starter · #1 ·
‘82 GL500 Interstate, second owner (technically third, but the 2nd guy had it for only a few weeks before giving it up), 6500 miles. Has sat for the past 15ish years.

Currently replacing all fluids and lube, and figuring out what needs repair or replacement.

There’s a fair amount coolant or water in the oil (looks like very light colored chocolate milk). Hoping it’s a plugged weep vent. Also the starter catches only 25% of the time, so likely gummed up springs or a bad clutch. Seems common enough, but am hoping not to drop the motor until I ride it for a while and figure out what I want to make of it.

I have the Rejuve Moto 2-2 headers on the way, and will likely pick up either 12" or 18" Cone Engineering silencers. Would it be worth the money for the Murray's carbs, or could I get away with rejetting the stock carbs?

She runs fairly well once she finally turns over and catches. Can’t wait to get her properly dialed in and roadworthy again. Likely will be taking off an parting out the front fairing, side bags, passenger seat and rear tail if anyone is interested.

Looking forward to all the great knowledge and guidance a group like this can provide and at some point paying it back.

Tire Wheel Fuel tank Automotive fuel system Vehicle
 

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I hope that you are not running on the "very light colored chocolate milk ". Assuming that you have put in fresh oil has it become "very light colored chocolate milk " again?
 

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'82 GL500 Interstate
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Discussion Starter · #3 ·
I hope that you are not running on the "very light colored chocolate milk ". Assuming that you have put in fresh oil has it become "very light colored chocolate milk " again?
No, sir. I've drained it all out, added back in some seafoam to coat the bottom of the innards and will drain that back out and add new oil and run it to see if it returns to chocolate milk or not.

Any recommendations on cleaning out the weep hole so I can rule that out as a culprit?
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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Murray's Mikunis will give you more power, but also more fuel consumption. It depends on what you want.
If it were me, I'd do everything else first. Carbs are an easy swap
 

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Any recommendations on cleaning out the weep hole so I can rule that out as a culprit?
Do you have an old bicycle spoke? Spray from WD40 or similar.

 
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'82 GL500 Interstate
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Discussion Starter · #6 ·
I agree with the sentiment that carbs are an easy swap and other, more important, things should come first - assuming that the stock carbs will be enough to handle the increased flow that the Rejuve 2-2 straight pipes and free flowing silencers will demand. I have heard/seen from some others that even rejetting and messing with the stock carbs could never get quite right, whereas the Mikuni VM34's will feed the beast perfectly..

While I enjoy the paradigm of the famed BJ English of "refurbish and reuse what you can" - I'd hate to spend time cleaning the stock carbs, buying new gaskets and needles and wasting time and effort that doesn't result in good performance.
 

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t the stock carbs will be enough to handle the increased flow that the Rejuve 2-2 straight pipes and free flowing silencers will demand.
The stock carbs are not much affected by exhaust changes so long as the intake is stock.
 
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Discussion Starter · #8 ·
The stock carbs are not much affected by exhaust changes so long as the intake is stock.
Good point.

My intent in replacing the headers and silencers first (aside from better sound and the fact that Rejuve only had 4 left and won't make more for a few months) is that I want to design and build around them and the engine as the main elements of the bike, rather than an improvement in power.

So, I'll spend the time to refurb the stock carbs and play with jetting as my first major piece of work on the bike. My Haynes Fuel Systems book is about to become my best friend.
 

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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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I forgot to say, Welcome, Ryan!
What part of Wisconsin are you in? The 15th annual Spring Ride is just a couple weeks away. (See the link in my signature.) Come ride with us if you're within reach of Minnesota.
 

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My Haynes Fuel Systems book is about to become my best friend.
Get Larry's book for these carbs/ see my sig line for a link. Keep all your stock brass parts...
 

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'82 GL500 Interstate
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Discussion Starter · #11 ·
I forgot to say, Welcome, Ryan!
What part of Wisconsin are you in? The 15th annual Spring Ride is just a couple weeks away. (See the link in my signature.) Come ride with us if you're within reach of Minnesota.
I'm in Madison, so a fair ways away - and likely I won't have the bike in shape by then - but thanks for the invite.. maybe next year!
 

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'84 CX650E that is evolving into a GL500
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A blocked weep hole won't cause coolant to get into the oil unless the water pump's mechanical seal is leaking too. There is an oil seal where the camshaft exits the rear of the crankcase and an air space that the weep hole connects to between that oil seal and the mechanical seal. The idea is that if either the oil seal or the mechanical seal fails what leaks past it will exit via the weep hole instead of trying to get past the other seal

Unfortunately the most common cause of "chocolate milk" oil is a blown head gasket (first they blow between the combustion chamber and the cooling jacket and soon after between the cooling jacket and one of the oil passages between the head and block).

Welcome to the forum. Please add your location and your bike's model and model year to your profile so that you don't have to remember to tell us every time and we don't have to keep asking when you forget (see Forum Settings link in my signature).

And welcome to the world of antique vehicle ownership (they own us, not the other way around). Your bike is about 4 decades old and may or may not have had all of the maintenance necessary to keep it safe & reliable so it is highly recommended to download the Factory Shop Manual for your model (available through the CX Wiki - link in my signature) and go through all of the service procedures, regardless of whether your bike has reached the specified mileage.
I also recommend looking on all rubber parts with suspicion because rubber does not age gracefully. If it has been sitting that long you don't need to check the date codes on your tires to know that they are over 5 years old and should be replaced no matter how good they look & feel (old rubber simply cannot flow around the irregularities in the asphalt well enough to grip, especially if it is cool or wet).
It looks like your bike still has the original rubber brake lines, which should have been replaced every 2 or 3 fluid changes (= 5 or 6 years) so they should be at the top of your to do list. I recommend shopping for modern stainless braided ones (they last practically forever and double the life of the fluid).
And don't forget things like the rad hoses and the boot between the engine and swingarm (they can crack on the bottom where you don't see it).

The best advice anyone can give you about customizing any vehicle is to get it safe & reliable in more or less original condition and use it for a while before you start making any changes so it can tell you what changes it needs to make it do what you want/need better. That approach almost always results in something you actually want to keep and use but making changes based on style or on what someone else (who may or may not really understand how the changes affect the way it works) has done often results in a piece of expensive yard art that you can't stand sitting on for more than a few minutes and might even be dangerous.
 

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'82 GL500 Interstate
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Discussion Starter · #13 ·
Unfortunately the most common cause of "chocolate milk" oil is a blown head gasket (first they blow between the combustion chamber and the cooling jacket and soon after between the cooling jacket and one of the oil passages between the head and block).
Thanks for the very helpful information and guidance!

Is it safe to clear the weep hole, refill with new oil, run the engine at idle up to temp for a period, then check the oil for changing color so that I could determine whether it's a faulty oil seal versus a gasket?

I'm not opposed to ripping into the engine, but would prefer to get the bike back to roadworthy and ride it for a while before doing that. But perhaps with it's age and years of sitting that would be the most appropriate thing to do..?
 

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'84 CX650E that is evolving into a GL500
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It makes more sense to figure out what the actual problem is before you start fixing things too (many of us had to learn that the hard way).

Other than trying to warm up the engine at idle your plan sounds good to me. It is always better to warm en engine up under moderate load and varying throttle; Normally this means drive away as soon as it is warm enough to pull without stalling and should be warm in under a block but in the shop you can sit with the rear brake on in gear and slip the clutch just enough to lightly load it while varying the throttle.
 
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