Need help to diagnose engine trouble...
 

So if you followed any of my other threads (Top end rebuild, spark plug reading), I have been going through some growing pains with my 2014 EX300.

Let me start at the beginning.

About 3 weeks ago I noticed a pin hole leak in my left radiator. I went and bought a set of ebay Chinese radiators (winner racing) as both were cheaper than just one OEM radiator.

So I installed the radiators (perfect fit) and unfortunately when removing the rubber caps from the openings, I forgot one when installing the radiators on the bike. I took the bike out for a test ride and it of course ran very hot and eventually was detonating left and right, pinging like a diesel. At the time I couldn't figure out what was wrong so I made some jetting adjustments and went back out for another test ride...same thing.

I know I overheated the bike pretty bad as I could smell the oil burning. Finally, I took the radiator apart and found the plug, removed it. By now, the bike was not running right even with the cooling system functioning properly. It made popping sounds on deceleration and would idle either too low or too high and was hard to start. If you let off the gas the bike would backfire and lurch forward on deceleration. The advice was to check for air leaks. I tightened everything down from the intake to the cylinder head. I found a bad choke plunger and replaced that, thinking air was coming in through the choke tube. I also noticed the throttle cable out of adjustment, so I fixed that. Another advice was to replace the exhaust header pipe gaskets/rings...did that still nothing.

Bike still ran very poor, like it was jetted badly (I knew this wasn't the case as before I had the overheat issue, it ran perfect with the current jetting). At this point I figured I may have fried the rings or top end, so I bought a Wossner forged piston kit with all new gaskets all around. I did the complete top end, fired her up and she ran good. Power was up and the deceleration popping was reduced quite a bit (but still present).

I took the bike out for the first long ride and it still ran like the jetting was still off (but much better than before) and toward the end of the ride, the bike started to ping again. I pulled over and found it was low on water by about 12 ounces I let it cool down, added water and headed home and it was OK. I rechecked the coolant level after the short ride home and it was down about 8 ounces again. Not sure if I had air pockets or if I am burning coolant.

For argument, lets say jetting is good, intake is all tightened down, new spark plug, new top end, new gaskets, new larger radiators. What the heck can be going on here? Could I have cracked/warped the head/cylinder? Would that cause it running like it was jetted poorly and overheating?

I am just at a loss of what to check next and I getting wary on just buying new random parts to try and solve the problem.

Check you water pump impeller

Come to think of it, the right side (return) radiator was very cool compared to the other side.

What am I checking for? That it turns? How do I know if it is bad?

Does your bike have a thermostat in the right side radiator hose? It may be stuck closed forcing the left rad to do all the work. The problems may have started with your plastic water pump impeller. After the overheating it is likely in worse shape. Checkpoint makes an alloy replacement. Most riders also remove the thermostat.

Yes it has thermostat. I have actually ordered a set of hoses without the thermostat.

I will check the impeller as well, anything specific to look for?

They tend to melt when the bike over heats

So I ordered a new impeller, a few gaskets and hose set without a thermostat.

We'll see how it goes.

I am hoping this is the issue and not a cracked/warped head.

Matto's has the samco hoses in stock. I got ride of the thermostat after it exploded.

We'll the problem is worse. Went to drain my oil and it looks like a shamrock shake. It is mint blue (color of my coolant) with the consistency of sludge/milk shake. Even with most of the oil drained my sight glass is still covered in sludge. Probably going to have to fill with Kerosene to get the sludge out. I imagine this is in my coolant system as well. so will need to drain and flush that. I could just explode right now in fury...:mad:

Obviously the coolant and oil mixed hence why I was overheating and the blue sludge. It can't be mixing at the head because there is no oil there, so the only other thing must be the water pump seals must be shot and allowed coolant/oil to mix.

Hopefully that is my only problem. Does my diagnosis sound correct?

Yes sounds like the water pump seals.


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