Cooling Issues

[n4mwd]

I have one of those infrared thermometers. We could meet up somewhere and compare bike temperatures.

[DaBlue1]

Originally Posted by FvnnyL3tt3r1ng

Ok, so far we have this:

New coolant after flush

New thermostat

New radiator cap

Bike still overheats, I watched as the coolant spilled out the overflow hose onto the ground so the gauge is reading accurately.

I now have an issue of low power. Tomorrow I will bust out the old compression tester and check the plugs. If those check out (please god please let them check out) then I'll be opening up the carb bowls to find out what the heck is going on.

Anyone have any ideas?? I was driving along and the engine starts to get hot (not in red zone mind you) and power starts decreasing. I drive it home on the shoulder going very very slowly. This bike keeps me on my feet I swear.

Before it got real bad the engine was pretty normal til about 7k rpms. I had a weird 30 minute phase where I was running on one cylinder a few weeks ago but I assumed it was either rain in the tank (it had been pouring) or the carbs passing a kidney stone.

Take a peak at the Trouble Shooting Guide to see what other factors can attribute to overheating and power loses.

Here are a few others;

Overheating:

Firing incorrect:

Spark plug dirty, broken, or maladjusted

Spark plug incorrect

IC Igniter trouble


Fuel/air mixture incorrect:

Main jet clogged or wrong size

Fuel level in carburetor float bowl too low

Carburetor holder loose

Air cleaner poorly sealed, or missing

Air cleaner duct poorly sealed

Air cleaner clogged


Compression high:

Carbon built up in combustion chamber


Engine load faulty:

Clutch slipping

Engine oil level too high

Engine oil viscosity too high

Drive train trouble

Brake dragging


Lubrication inadequate:

Engine oil level too low

Engine oil poor quality or incorrect

[cuong-nutz]

How did the coolant look when you drained it?

• Was it clear or cloudy?
• bright green or dark green with flaky sparkles?

Bright green and clear is good. Anything other means your coolant is old and or contaminated. What ratio of coolant to water did you use? 50/50? Make sure you are using distilled water and not tap water. Tap water contains minerals as well as carbonate and chlorine which will eat up the aluminum and metal causing scaling and corrosion.

How did you go about flushing the the cooling system? Did you drain all the coolant out of the block radiator? What I do is pull the hose on the left side of the engine at the radiator and drain the radiator there, undo the drain bolt on the block under the header, and drain bolt at the water pump. Once drained, I'll fill the system back up with distilled water and run the bike till it warms up. and drain it. Reason I used distilled water is so you can see if there are any debris in your cooling system plus you're flushing the system and you'd don't want to waste coolant unless you're big balling and don't care about wasting money on coolant.

Another thing but I'm probably sure you've checked is make sure your radiator fins are not bent or clogged with bug guts and mud or corroded away.


To be honest, sounds like you've blown a headgasket.

[FvnnyL3tt3r1ng]

The headgasket is what I'm worried about! Bike sounds a little farty under throttle now.

I just wanna check the spark plugs, the compression, and run a leak down test to see my status with those.

My coolant looked very like new. There was a bit of particles in the overflow but for the most part it looked just fine.

I hooked a hose up to the filler neck and flushed it out of the two drain holes until it was clear as could be.

I really doubt the jetting is off I haven't had any issues since they've been installed and the fact the thermo switch is busted tells me something may have broken when my bike got hot before being noticed by me.

I might look into that thermo it doesn't seem to cost too much (harbor freight) but I do have a contact type one on my ammeter.

I'm gonna focus on engine type issues right now because I really don't think the cooling system is at fault right now.

If all checks out I will pull the carbs to see if the lack of power is from a clog in the mains.

[n4mwd]

When you flushed, did you flush backwards up the radiator with the hose to make sure there was good flow through it?

Have you noticed any white smoke in the exhaust?

Have you noticed and change in the oil that resembles puke?

When you turn the key on, does the oil light come on until you start the bike?

[FvnnyL3tt3r1ng]

I didn't backfill like you suggested no.

The oil looks normal.

No smoke in the exhaust I was worried about that and did check.

I believe the oil light goes on then off when I turn the key to ON.

[n4mwd]

If you didn't backwash the radiator, then you didn't flush it. By flushing it in the opposite direction, gunk and junk are blown out that are clogging it from the normal direction.

When you refilled everything, did you run it until warm with the cap off? This is what gets the air out.

Measuring the exact temperature of the head is what needs to be done next. You said it didn't actually get past the redline on the temp gauge, but it presented symptoms of coolant failure (power loss). So either the temp sensor in the thermostat housing is wrong or the engine really isn't overheating. The thermometer will tell you which is which.

[FvnnyL3tt3r1ng]

Yeah I burped the cooling system when I refilled.

As of now we have this:

Compression Test:

Cyl 1 : 80psi
Cyl 2: 180psi

Leak down test

Cyl 1: No leak
Cyl 2: No leak

Carb's main jets were fine, nothing cloggin them.

Spark plugs tested out fine both left and right.

Looks like I'll be taking the head off and putting a new head gasket in. I do need to take a look at the pistons and see if theyre fine as well. This still doesn't tell me why the engine was overheating in the first place. I can only guess when the thermostatic switch broke the engine overheated and possibly damaged something creating this condition.

[n4mwd]

Yeah, 80psi is no good. Did you get a chance to measure the actual engine temp with an external thermometer before you took it apart?

When you remove the cylinder head, make sure you check everything for warpage. If you were actually overheating, then warpage is a real threat.

[FvnnyL3tt3r1ng]

Originally Posted by n4mwd

Yeah, 80psi is no good. Did you get a chance to measure the actual engine temp with an external thermometer before you took it apart?

When you remove the cylinder head, make sure you check everything for warpage. If you were actually overheating, then warpage is a real threat.

I can check the temp tomorrow if you'd like. Everything is back together atm. I mean if I keep it running it will run so hot I have to turn it off...... It's jumpy

[FvnnyL3tt3r1ng]

Update:

Did another compression test one cylinder one:

Wet test: 120 Psi
Dry test: 80 Psi

Is this saying a lot? I didnt run a wet test on cyl 2 but I imagine it should read similar if nothing is wrong with the piston right??

[n4mwd]

Originally Posted by FvnnyL3tt3r1ng

Update:

Did another compression test one cylinder one:

Wet test: 120 Psi
Dry test: 80 Psi

Is this saying a lot? I didnt run a wet test on cyl 2 but I imagine it should read similar if nothing is wrong with the piston right??

Do you remember what the values were right after you finished your valves?

Generally a higher wet test tends to scream bad rings.

[FvnnyL3tt3r1ng]

Originally Posted by n4mwd

Do you remember what the values were right after you finished your valves?

Generally a higher wet test tends to scream bad rings.

yeah I believe they were 180 after I did the valves back in Nov.

[n4mwd]

Originally Posted by FvnnyL3tt3r1ng

yeah I believe they were 180 after I did the valves back in Nov.

So the question is whether the rings are coincidental or if the overheating actually caused them to go bad. How many miles right now?

Also, did you get a true temp reading with your thermometer yet?

[Motofool]

Originally Posted by n4mwd

So the question is whether the rings are coincidental or if the overheating actually caused them to go bad.....

If the temperature that the top ring reaches is much higher than 600 F, two bad things may happen:
-The ring's gap may not be enough to accommodate the dilatation and the ring may break.
-The ring's spring action against the wall of the cylinder may result reduced.

[n4mwd]

The only thing is that without an actual temperature reading, there is no way to really say if the engine actually overheated or not.

But if the ring did break, as opposed to just wearing out, then its probably scoring the cylinder every which way.

[FvnnyL3tt3r1ng]

I had no (noticeable) compression issues before the other day. I don't know what the source of the original overheating was.

The bike has 19k miles now.

I never got a temperature reading but I'm pretty sure the high reading on the gauge put together with the coolant overflow is evidence enough. I'm not running the bike to get a temperature reading.

[n4mwd]

Originally Posted by FvnnyL3tt3r1ng

I had no (noticeable) compression issues before the other day. I don't know what the source of the original overheating was.

The bike has 19k miles now.

I never got a temperature reading but I'm pretty sure the high reading on the gauge put together with the coolant overflow is evidence enough. I'm not running the bike to get a temperature reading.

It really sounds like pulling the cylinders and heads is the next step. While you have everything apart, I would also go ahead and pull the water pump and inspect it. Something in your cooling system failed. The water pump is pretty much the only thing that hasn't been checked.

[FvnnyL3tt3r1ng]

Pulled head and block out this morning. Found the intake springs for cylinder one left side (as you're sitting on the bike) laying underneath the cam. The rocker was lying in the corner and one of the valve keepers has gone missing while the other one seems to have been destroyed. As far as the rings I don't notice anything visually wrong with them. Cylinder 2's piston looked a little purple ish in the spots around the rings while cylinder one's piston looked fine. There is a little bit of scratches on the intake valve stem and the washer piece that sits on top of the springs.

I don't know if that was causing the overheating somehow?

I did backwash the radiator and all was well there fyi (n4md).

I've got to make a parts list and put in an order tonight while I try to figure out what my next step is.

[FvnnyL3tt3r1ng]

If I run the bike with the radiator cap open and after the thermostat opens I observe coolant flow going into the radiator, is there any need to check the water pump? I'd just rather not pull it out and risk damaging an o-ring.

I revved the bike and observed greater flow as well after the thermostat had opened....

[n4mwd]

Originally Posted by FvnnyL3tt3r1ng

...Found the intake springs for cylinder one left side (as you're sitting on the bike) laying underneath the cam. The rocker was lying in the corner and one of the valve keepers has gone missing while the other one seems to have been destroyed.

As far as the rings I don't notice anything visually wrong with them.

Cylinder 2's piston looked a little purple ish in the spots around the rings while cylinder one's piston looked fine.

There is a little bit of scratches on the intake valve stem and the washer piece that sits on top of the springs.

I don't know if that was causing the overheating somehow?

Originally Posted by FvnnyL3tt3r1ng

If I run the bike with the radiator cap open and after the thermostat opens I observe coolant flow going into the radiator, is there any need to check the water pump? I'd just rather not pull it out and risk damaging an o-ring.

I revved the bike and observed greater flow as well after the thermostat had opened....

I thought you had a pro reset your valve keepers correctly the last time you had it apart. The valve keepers don't usually fail. I have never heard of them failing on any kind of engine. However, if one was left in the condition like I saw them in when I was there, then they will fail for sure.

Since you have the engine apart, go ahead and examine the cylinder block. You need to make sure that there is nothing blocking the flow. Its possible that you have flow around one cylinder, but not the other. Use a hose with a jet nozzle to blast into each side. Wipe the inside cylinders dry when done.

The reason that I think inspecting the water pump is necessary is not because it isn't working, but because a piece of the impeller may have come loose and gotten wedged in the cylinder block - thus causing a restricted flow around one cylinder. You don't have to pull the whole pump, just removed the cover. You'll need a new gasket probably. So the purpose is to inspect the impeller for damage.

You also need to check the cylinder section, top and bottom, and the head for warpage. Just put a straight edge of some kind across the top and look for gaps. If the head and cylinders got to a certain temperature, then they will warp and will need to be machined flat again.

Since you have loose parts in there, you will probably want to remove the clutch cover. A lot of times that is where they end up. You will want to inspect the lower timing chain guide that is just under the crankshaft. When things get wedged under the timing chain, this is a part of the main block that tends to get snapped off. You need to recover these things because if they get wedged between two gears, they can cause a lot more trouble than you have now.

I actually think the problems are unrelated because it sounds like cylinder #2 was the one that was overheating and cylinder #1 was the one that failed.

Some pictures would be helpful.

[n4mwd]

I was just thinking about your valve keepers. Because of your unique assembly technique back in November, I'm thinking that the spring caps may have been damaged causing excessive play with the keepers, or perhaps one of the keepers was cracked somehow. So you might want to replace the spring caps as well.

Here's a guy on ebay selling the whole mess for $16 shipped.

[Motofool]

Originally Posted by FvnnyL3tt3r1ng

.........Found the intake springs for cylinder one left side (as you're sitting on the bike) laying underneath the cam. The rocker was lying in the corner............

I don't know if that was causing the overheating somehow?...........

With the spring gone, what was holding the valve up?
Did you hear any air leak during leak down test?

I believe that the temperature of that cylinder should have been lower than normal, as well as the compression and generated power.
Did you noted decreased power at any point since your last repair?

[n4mwd]

The piston probably was smacking it. So the valve may also be bent. With a bent valve and no rocker, it might have just stayed in the up position. I don't see how he was getting any kind of power from that cylinder at all.

[Motofool]

Originally Posted by n4mwd

The piston probably was smacking it. So the valve may also be bent. With a bent valve and no rocker, it might have just stayed in the up position. I don't see how he was getting any kind of power from that cylinder at all.

Indeed !!!

Unless it just happened as a consequence of the over-heating.

Your idea of debris from the impeller is very good.

I have been researching for safe chemical cleaners for his aluminum radiator, but I have found none.

I strongly believe that he may have some hard deposits inside the narrow tubes of the radiator which impair the design heat transfer rate (just a hypothesis, of course).

It is sad to see such a chain of problems

[FvnnyL3tt3r1ng]

Originally Posted by Motofool

With the spring gone, what was holding the valve up?
Did you hear any air leak during leak down test?

I believe that the temperature of that cylinder should have been lower than normal, as well as the compression and generated power.
Did you noted decreased power at any point since your last repair?

The valve just stayed in the up position even after I took the head out.

I did indeed have the shop install the keepers I don't know why they would want to come out as they did. The leak down test showed no leaks of course.

This problem happened very recently because I lost power after I warmed the bike up to test the cooling system again. That's when I thought the head gasket was gone but it was probably this valve causing the lack of power.

I don't know whether or not to order new rings for my pistons. I'd rather not do any unnecessary repairs at this time.

[FvnnyL3tt3r1ng]

2013-05-25 13.03.53.jpg
Cylinder 1 ^^
2013-05-25 13.03.46.jpg
Cylinder 1 ^^
2013-05-25 13.03.03.jpg
Cylinder 2 ^^
2013-05-25 13.02.55.jpg
cylinder 2 ^^

[FvnnyL3tt3r1ng]

Originally Posted by n4mwd

I thought you had a pro reset your valve keepers correctly the last time you had it apart. The valve keepers don't usually fail. I have never heard of them failing on any kind of engine. However, if one was left in the condition like I saw them in when I was there, then they will fail for sure.

Since you have the engine apart, go ahead and examine the cylinder block. You need to make sure that there is nothing blocking the flow. Its possible that you have flow around one cylinder, but not the other. Use a hose with a jet nozzle to blast into each side. Wipe the inside cylinders dry when done.

The reason that I think inspecting the water pump is necessary is not because it isn't working, but because a piece of the impeller may have come loose and gotten wedged in the cylinder block - thus causing a restricted flow around one cylinder. You don't have to pull the whole pump, just removed the cover. You'll need a new gasket probably. So the purpose is to inspect the impeller for damage.

You also need to check the cylinder section, top and bottom, and the head for warpage. Just put a straight edge of some kind across the top and look for gaps. If the head and cylinders got to a certain temperature, then they will warp and will need to be machined flat again.

Since you have loose parts in there, you will probably want to remove the clutch cover. A lot of times that is where they end up. You will want to inspect the lower timing chain guide that is just under the crankshaft. When things get wedged under the timing chain, this is a part of the main block that tends to get snapped off. You need to recover these things because if they get wedged between two gears, they can cause a lot more trouble than you have now.

I actually think the problems are unrelated because it sounds like cylinder #2 was the one that was overheating and cylinder #1 was the one that failed.

Some pictures would be helpful.

The shop did install the valve keepers for me.

I plan on removing the clutch cover after I pick up my oil pan from storage but probably not before I get new parts in. I don't want my engine sitting without oil in it.

Ill check the head and block for warpage as well as the impeller for damage.

[n4mwd]

The pistons and rings really don't look all that bad to me. Take a look at the top of the piston and look for dings and cracks.

I think the keepers and valve caps were damaged by your previous installation attempt. I recommend you buy the kit on ebay for $16. You should replace all your old valve caps and keepers. Plus you are going to need a new spring set for the one valve.

You need to determine why the valve is stuck in the up position. More than likely, something is bent.

Also, before you put anything back together, you need to determine for sure what was causing the overheating. Otherwise its just a repeat performance.

[FvnnyL3tt3r1ng]

Originally Posted by n4mwd

The pistons and rings really don't look all that bad to me. Take a look at the top of the piston and look for dings and cracks.

I think the keepers and valve caps were damaged by your previous installation attempt. I recommend you buy the kit on ebay for $16. You should replace all your old valve caps and keepers. Plus you are going to need a new spring set for the one valve.

You need to determine why the valve is stuck in the up position. More than likely, something is bent.

Also, before you put anything back together, you need to determine for sure what was causing the overheating. Otherwise its just a repeat performance.

I am really stumped on what was causing the overheating! Maybe the impeller check will help me understand better

[n4mwd]

Both the cylinder and the valve head have coolant going through them. The hose with a jet nozzle may be the best way to see if you can flush something out.

I have seen in car engines, but I'm not sure about the Ninja, that they use metal springs in the radiator hoses which can rust, break apart and jam the impeller and clog the water jacket of the engine. Again, I'm not sure about the Ninja, but you could find all sorts of surprises in there.

The valve keepers need to fit inside an exact diameter cup inside the valve spring caps. I think the heat plus the previous installation attempt expanded them just enough to cause the keepers to fail. That's why I suggested buying the $16 valve set from the guy on ebay. They are quite expensive buying new.

[FvnnyL3tt3r1ng]

I've bought the set off ebay already, good savings there.

[FvnnyL3tt3r1ng]

The head of the intake valve was a little crooked. I don't think this was my doing when I was removing it as I would expect the stem to be bent. Just put in an order from partzilla totalling $82 + shipping. Not bad considering I thought it would be much more. Now time to fish out the broken parts and test the coolant passages.

[n4mwd]

Might be somebody on ebay selling the valves cheap.

[FvnnyL3tt3r1ng]

Got the clutch cover off and drained the oil. I have yet to find the 6mm nut that came off the rocker! What should I do?? I put a flashlight into the crankcase and I didn't see anything either..... It just disappeared! Could it have gotten into an oil passage? The mechanic at the shop said my valves could have been tight which would cause the overheating. I never thought of that but I did adjust them probably ~3k miles ago.....

[Motofool]

Originally Posted by FvnnyL3tt3r1ng

Got the clutch cover off and drained the oil. I have yet to find the 6mm nut that came off the rocker! What should I do?? I put a flashlight into the crankcase and I didn't see anything either..... It just disappeared! Could it have gotten into an oil passage? The mechanic at the shop said my valves could have been tight which would cause the overheating. I never thought of that but I did adjust them probably ~3k miles ago.....

The Ninja's engine uses a wet sump lubricating oil management design, which means that after the oil leaves the high pressure part of the circuit, it falls by gravity into the collecting pan at the bottom.

Your nut must be in between that pan and the valves' train.
Maybe a magnet could help?

Tight valves get burned because they don't "kiss" the seats long enough to be properly cooled.
For the very same reason, they never cause engine's overheating.

[FvnnyL3tt3r1ng]

There was a diagram posted of this somewhere do you know where I could find it?

[Motofool]

Don't remember.

This schematic is for the new-gens:

http://xmanualpdf.com/wp-content/upl...sers-Guide.jpg

[n4mwd]

The nut has to be in there somewhere. Its not going to get sucked into the oil intake because of the oil pickup screen. You should probably pull that off if you haven't already and check to see if it got washed in there. Once the screen is off, you can stick your finger up in there and feel around for it.

While you have the clutch cover off, check to see if the cam chain guard under the crankshaft is still there. That will tell you if the cam chain was affected.

I still think the overheating is a separate issue. You just did the valves so I don't think they were out.

Oh, and you'll need a new oil screen gasket. They aren't that expensive, but since they are paper, you can make your own out of gasket paper.

[FvnnyL3tt3r1ng]

Lots of carnage in that oil screen.

I really wish lowes or home depot carried our mounting bolt nuts!!!

well looks like i sheered a cam cap bolt.....

i also need a new rocker/screw as they are both stripped!

The screw in my chain tensioner housing rounded making it a real PITA to install. (if I even can).

Such a frustrating process!!! I wanna splurge and buy a used engine!!!