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Discussion Starter · #1 ·
I think I need to pull my heads.

I was test driving the new electric fan I put on it because the mechanical fan had nasty cracks on it. I had let it sit in the garage and heat up then throw the fan on and it did a great job of cooling the bike. I figured it would be good to go!



I went about a mile and at a light heard this loud ticking it was consistent but not with the the RPM or anything I could figure.

I pulled away from the light and the temp gauge started to enthusiastically climb. With a quickness! I have a switch for the electric fan and I turned it on. I coasted as much as I could and watched the temp gauge. Even driving at 40 -45 mph the temp was climbing.

It never overheated but it got real hot.

I got home and shut it off, put a box fan on it to help it cool.

Now it will not start unless the choke is on. If I push the choke in it stalls.



Also I pulled the plugs (1/2 the reason for the ride) left one looked good. Right one looked all carbon-ed up and wet. I pulled compression. Left side still holding at a little over 60 (same as before) right now at 40 (it was 90 before). I think I lost the head gasket.

No water in the oil although!

So this week I am pulling heads.



Anything I should specifically look for? Any way to check the rings and such while I am in there? I know to look at the cylinder walls for scoring, but little else.

Also what would you do with the head? I always just took it to a machine shop and had them rework the heads but I am over budget and getting deeper soooooooo......

Thanks for the help!

Tony
 

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Tony,

I would not pull the heads until you get a lot of responses from other members here that know a lot more than I do. Haste makes waste. Billrod
 

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Discussion Starter · #3 ·
Tony,

I would not pull the heads until you get a lot of responses from other members here that know a lot more than I do. Haste makes waste. Billrod


You are right. I will not be tearing into it until tuesday or wednesday but the fact is with compression THAT low on the right the heads are going to have to come off to find out what is going on.

Thankfully there are not any catastrophic metal noises just low compression and no run.



I might have lost spark which would cause these symptoms I think but that compression just ain't right.
 

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Did the bike work well before the electric fan install ? How hot did it get, into the red ? Did the fan come on when riding or only when you switched on the fan manually ? was the ticking from the fan blade hitting something, or was it there when the fan wasnt running ?



When you checked compression did you hold the throttle wide open ? (allows max air for a more accurate reading).



If the fan only comes on with a manual switch, then it isnt surprising that the temp kept climbing. Once the fan is turned on it will take a while to cool the fluid in the rad, especially if the thermostat is staying open not allowing the coolant to stay in the rad for very long.



I would check the compression again and do a "nasty test" (some people will hate me for this one). Get a long Q-tip and stick it in the suspect cylinder plug hole...... then taste it (yea I know, nasty). If there is any coolant there you will know right away.
 

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Discussion Starter · #5 ·
Did the bike work well before the electric fan install ? How hot did it get, into the red ? Did the fan come on when riding or only when you switched on the fan manually ? was the ticking from the fan blade hitting something, or was it there when the fan wasnt running ?



When you checked compression did you hold the throttle wide open ? (allows max air for a more accurate reading).



If the fan only comes on with a manual switch, then it isnt surprising that the temp kept climbing. Once the fan is turned on it will take a while to cool the fluid in the rad, especially if the thermostat is staying open not allowing the coolant to stay in the rad for very long.



I would check the compression again and do a "nasty test" (some people will hate me for this one). Get a long Q-tip and stick it in the suspect cylinder plug hole...... then taste it (yea I know, nasty). If there is any coolant there you will know right away.


Did the bike work well before the electric fan install ?

Had just gotten it on the road. So there was not much history to be had. I had less than 100 miles on it since I got it running again. It sat for about 28 years without running before I got it. It SEEMED ok but was running hot which was part of the reason for the e-fan install.



How hot did it get, into the red ?

Not to the red. Never since I have had it. It was close twice. The time before I was caught in traffic and it cooled back to normal about the time I started moving quickly. I was up to about 75 within a few seconds of getting free it was fine at those speeds.



Did the fan come on when riding or only when you switched on the fan manually ?

My Thermal switches are not here yet so only manual on the fan. It was still climbing when I was driving at about 40 mph although which I would NOT expect.



was the ticking from the fan blade hitting something, or was it there when the fan wasn't running ?

It was there when the fan was not running. I actually could not tell if it even came from me or the car behind me.

I figured it must have been me once the misbehavior started.



When you checked compression did you hold the throttle wide open ?

Throttle wide open choke wide open. Took it twice that way. Bother were very similar. like 40 and 38 or some such. Very small difference between them. I considered it negligible.





Never even heard of the 'nasty' test before.

I am not so keen on the taste of antifreeze.

I will smell it and try to make a determination.

If I cannot figure it out I might try the taste method.
 

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How's your coolant level? Did you change out your thermostat? A sticking thermostat will definitely cause your bike to overheat. Overheating can cause piston rings to stick in piston grooves which can give a low compression reading.



I had a CX500 with overheating issues some years back. After trying a lot of things unsuccessfully, the problem turned out to be the impeller splines had completely sheared off. Result was the impeller was lazily turning on the end of the cam shaft so I was barely getting any coolant circulation. Lucky for me, the camshaft was fine and was able to find an impeller on ebay for $15.
 

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Discussion Starter · #7 ·
How's your coolant level? Did you change out your thermostat? A sticking thermostat will definitely cause your bike to overheat. Overheating can cause piston rings to stick in piston grooves which can give a low compression reading.



I had a CX500 with overheating issues some years back. After trying a lot of things unsuccessfully, the problem turned out to be the impeller splines had completely sheared off. Result was the impeller was lazily turning on the end of the cam shaft so I was barely getting any coolant circulation. Lucky for me, the camshaft was fine and was able to find an impeller on ebay for $15.


How's your coolant level?

Ran it up to temp earlier in the day watching the coolant. It went from a healthy color to the brown that everything I put in it turns. I have run the vinegar up to temp and drain about 6 times it still comes out like light tea. So yes the level is good. Well I have not checked since the ride but... it was good before.



Did you change out your thermostat? A sticking thermostat will definitely cause your bike to overheat.

Brand new thermostat when I put it all back together. I suspect there is some crud blocking a water passage in one of the heads. Probably on the right because it is the problem child.



I think my flow is good because I can feel the radiator getting hot. You can watch the temp gauge and once it hits the fatter line the radiator starts to get hot. I bought a thermal laser sensor thingy and the right head was consistently hotter then the left by several degrees. I do not remember the exact amount but more than 5.



Lets assume the rings decided to stick. Can I put some PB Blaster in there and have any hope of getting them to cooperate? I did not do the oil in the cylinder test.
 

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Is the bike actually overheating or is it,"Saying" it's overheating?



Check 7v regulator,



http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=8&t=257



Also make sure that the bracket at the thermostat is correctly grounded.There's only,"One" bolt that does this job,not the two that secure the Thermostat housing.If this is not secure the gauge will read high.
 

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Discussion Starter · #9 ·
Is the bike actually overheating or is it,"Saying" it's overheating?



Check 7v regulator,



http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=8&t=257



Also make sure that the bracket at the thermostat is correctly grounded.There's only,"One" bolt that does this job,not the two that secure the Thermostat housing.If this is not secure the gauge will read high.


Shep the gauge climbs slowly and when it was sitting in my garage at idle with the fan on it never got more than slightly past where the temp gauge line gets thicker.



I have 7 volts and when I ground the gauge wire it climbs slowly.



It seems to get hot when I ride it and get the RPM above idle.

That is when it was running. I am pretty sure I lost spark on the left but have not checked yet.
 

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Did you start the bike cold with the rad cap off and allow the bike to come up to temp? Maybe there is air in the system? Run it with the cap off until the thermostat opens. But changing the head gaskets is a good idea if you don't know when the last time they were changed.
 

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. Left side still holding at a little over 60 (same as before) right now at 40 (it was 90 before).

Tony


Forget about any `overheating` problems for the time being, get the basics right first.

Those compression test results, if accurate, indicate a very tired engine, and the reason why they are so low must be investigated.

How does it run with such low compressions? Pretty lethargic i would of thought?



If the bike really has sat for 28 years the rings could of stuck i suppose, either through just being unused for such a long time or gunk/corrosion which may of accumulated in the (damp?) cylinders over such a long time being rammed into the piston ring lands when it was started after such a long time.



If you`re confident about those compression test results i`d remove the heads and check what you can there - head gaskets, valves, bores etc.

If you don`t find anything obvious or conclusive about why you`ve lost so much compression - such as flakey head gasket, corroded valve seats/valves/ eroded cylinder jacket (seen that on 650`s..) - a full-on engine strip may be in order to remove the pistons for inspection.

That`s gonna` cost a bit of $, but if you do the top-end and still have ring/bore issues after re-assembly it`s going to be wasted $ and you`ll still have a poorly engine.

Decision time...



To be honest, a bike such as that one with that sort of history, if it has `issues` soon after starting up, if it were mine i wouldn`t bother fannying around too much i`d just strip it right down and inspect it straight away, it`ll save hassle in the long run.
 

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Discussion Starter · #12 ·
Forget about any `overheating` problems for the time being, get the basics right first.

Those compression test results, if accurate, indicate a very tired engine, and the reason why they are so low must be investigated.

How does it run with such low compressions? Pretty lethargic i would of thought?



If the bike really has sat for 28 years the rings could of stuck i suppose, either through just being unused for such a long time or gunk/corrosion which may of accumulated in the (damp?) cylinders over such a long time being rammed into the piston ring lands when it was started after such a long time.



If you`re confident about those compression test results i`d remove the heads and check what you can there - head gaskets, valves, bores etc.

If you don`t find anything obvious or conclusive about why you`ve lost so much compression - such as flakey head gasket, corroded valve seats/valves/ eroded cylinder jacket (seen that on 650`s..) - a full-on engine strip may be in order to remove the pistons for inspection.

That`s gonna` cost a bit of $, but if you do the top-end and still have ring/bore issues after re-assembly it`s going to be wasted $ and you`ll still have a poorly engine.

Decision time...



To be honest, a bike such as that one with that sort of history, if it has `issues` soon after starting up, if it were mine i wouldn`t bother fannying around too much i`d just strip it right down and inspect it straight away, it`ll save hassle in the long run.


Eurovee,

I agree. I am rather concerned about parts availability like rings, bearings, and such.

Even if I did pull the pistons and all it does not help if I cannot find parts.

I do intend to just pull the heads and do an inspection. I am concerned about my lack of knowledge of the valves. I will post images and hopefully someone on here will say yeah or nay...



I am going to check the spark tonight because I suspect I lost the spark on the right.
 

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From what you ahve indicated it does sound like a few coolant passages may be a bit blocked or half blocked. As for the nasty test, there is absolutely no mistaking coolant in a cylinder if you taste it LMAO hard to go on smell, but taste ... its like concentrated liquid sugar. It is toxic, but a dab from the end of a q-Tip wont hurt. If it doesnt taste sickly sweet then you fairly sure there is no coolant leak into the cylinder.



I would keep flushing out the cooling system until you dont get any more crap coming out. Im not sure how the bike would like it (someone here with more experience may be able to answer) but when I had problems like this with my old Dart I ran a chemical flush trough it. You would be surprised to see just what comes out. Since I havent done any engine work since my 69 Dart (car got stupid with no reoom in the engine compartment and tons of polution crap) I dont know if a chemical fluch would hurt the engine ... shouldnt as its safe of steel and aluminum.
 

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Discussion Starter · #14 ·
Did you start the bike cold with the rad cap off and allow the bike to come up to temp? Maybe there is air in the system? Run it with the cap off until the thermostat opens. But changing the head gaskets is a good idea if you don't know when the last time they were changed.




Did this the morning before the ride. So there should have been no bubbles.

I did it on the center stand.



Just an update.

My left side has good blue-white spark my right side has orange-red spark.

The compression has found its way back up to about 65 on the right did not recheck the left.



I am going to order in a set of those cheap coils and see if they help. I do not want to spend another $175 for an ingtech. If I have to I guess I will but... Coils first.
 

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Discussion Starter · #15 ·
I have the right head ready to be removed.

The next step in the manual is simply

"Remove head"

As we all know these things do not come apart that easily.

If this was a car I would take a small block of wood and tap on the wood while it is against the head. The tapping would be done with a medium size framing hammer (14 oz or so ... whatever I grabbed first).

I am not confident that method is OK on this bike.

What is suggested by the experts here?



I found some more milkshake in with the bolt in the upper right corner of the head. The one holding it down.

I do not know if that was the head gasket weeping or if it is leftover from when I had milkshake in it before.
 

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When I took mine off I did use a few taps from a rubber mallet, which wasnt effective, and moved to a steel hammer and paint stick. I ended up using a flat thin butterknife (wife got mad but things are great for gasket breaking lol) and it loosened up and came out. Wasnt too hard as I just made sure I went in the gasket (since I would never reuse a head gasket) and followed by a few light taps to the head it came free.



Note to self, buy some more butter knifes to replace the broken ones (no, not on the head, the one I used as a scraper to clean out the swarf tray on the lathe lol)
 

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Discussion Starter · #17 ·
When I took mine off I did use a few taps from a rubber mallet, which wasnt effective, and moved to a steel hammer and paint stick. I ended up using a flat thin butterknife (wife got mad but things are great for gasket breaking lol) and it loosened up and came out. Wasnt too hard as I just made sure I went in the gasket (since I would never reuse a head gasket) and followed by a few light taps to the head it came free.



Note to self, buy some more butter knifes to replace the broken ones (no, not on the head, the one I used as a scraper to clean out the swarf tray on the lathe lol)


Sounds like if I use a thin paint scrapper it will be OK.

I have two concerns



1)deforming the aluminum and damaging the head.

2)if I destroy the gasket can I still tell where the leak was or if it had one?



Of course I looked at fleece-bay earlier and a set of heads that look OK are about $75 including shipping so it would not be the end of life as I know it. Just another step beyond budget. At least the head gaskets were part of the budget!

Thanks!
 

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Well, a paint scraper would also work well. If you are carefull you should be able to use the scraper to get in a bit, and thats usually all it takes. Even without a scraper I doubt you would be able to get it off without killing the gasket, they are usually paper and thin metal, and after many years get stuck good. When I got mine off I didnt have to jam the knife all the way in, only about 1/4" to 1/2", just enough to get a little pressure. Then a fer hammer taps and it freed up. Unless you pound the scraper in with a sledge hammer, yu shouldnt have to worry about the heads. A chisle or screwdriver blade will mar the head if used as a pry bar, but all it needs is a little extra 'pressense pressure" in the gap and couple of taps. Once it comes free just be carefull as there are 2 locator dowls that can easily fall into a coolant passage.



Even if you get REALLY lucky and the gasket doesnt seperate on both pieces, you will probably not be able to spot a leaky spot in the gasket unless its really bad and has been there for a long time. You will have to look for clues on the mating surfaces and especially the inside of the head.



Getting the heads off will be the easy part, getting the old gasket off the head and block is the pain part lol.



P.S. Would still 'taste" for coolant in the cylinder before popping the head off, if coolant IS there, you definatly have a leak. Once you pop the head you can no longer tell, as some coolant WILL get in the cylinder (even after draining the engine coolant) from the head passages.
 

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Discussion Starter · #19 ·
Well, a paint scraper would also work well. If you are carefull you should be able to use the scraper to get in a bit, and thats usually all it takes. Even without a scraper I doubt you would be able to get it off without killing the gasket, they are usually paper and thin metal, and after many years get stuck good. When I got mine off I didnt have to jam the knife all the way in, only about 1/4" to 1/2", just enough to get a little pressure. Then a fer hammer taps and it freed up. Unless you pound the scraper in with a sledge hammer, yu shouldnt have to worry about the heads. A chisle or screwdriver blade will mar the head if used as a pry bar, but all it needs is a little extra 'pressense pressure" in the gap and couple of taps. Once it comes free just be carefull as there are 2 locator dowls that can easily fall into a coolant passage.



Even if you get REALLY lucky and the gasket doesnt seperate on both pieces, you will probably not be able to spot a leaky spot in the gasket unless its really bad and has been there for a long time. You will have to look for clues on the mating surfaces and especially the inside of the head.



Getting the heads off will be the easy part, getting the old gasket off the head and block is the pain part lol.



P.S. Would still 'taste" for coolant in the cylinder before popping the head off, if coolant IS there, you definatly have a leak. Once you pop the head you can no longer tell, as some coolant WILL get in the cylinder (even after draining the engine coolant) from the head passages.


Your right.

I cannot see where the leak (assuming there was one) was at.

I will post pictures tomorrow. It is WAY past bed time tonight.

Good night!
 

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Discussion Starter · #20 ·
OK I have the heads off.

I inspected the cylinder walls. Smooth as glass. They are reflective with no apparent blemishes.

I sprayed the pistons down with PB Blaster on the chance the rings are stuck. It might help or it might not but it will not hurt.



Anyway. I saw nothing obviously wrong with the valves. I do not have the equipment to pull the valves. I am going to post the images here and y'all please tell me if you think the heads need to be taken to a machine shop for valve jobs! A friend at work said put it back together and give it a try the head gaskets are only a few $$ so if the are not good no big loss. Well I am waiting on a new coil sooo I have some time.



Oh the inch or more of slime and crud built up around the water jacket might have been helping it to run so hot. I am guessing on this one. The water passages in the heads were fairly clogged also.



Here are the pictures.



Left Side















Right Side













So thoughts??

If y'all say put the heads back on I will do that tomorrow and hopefully have great compression soon!



Thanks!
 
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