RX3 Cooling System

[pyoungbl]

Originally Posted by willy dog

i do believe the fuel in the catch tube is because of engine running "cold" but for now i think i will just drain it

The issue is not so much fuel in the oil as what happens to the lubrication properties of the oil when you get too much fuel mixed with that oil. The oil analysis I have gotten shows excess fuel in the oil and also that the viscosity of the oil has gone to hell due to that excess fuel. If we can get the oil up to about 190F much of that fuel will be vaporized (along with some water). Some of that vapor will end up in the catch tube, some will go into the air box. I, for one, don't care which path the vapor takes just as long as it ain't in my oil. Luckily we have ball bearings throughout the engine and those bearings are much more tolerant of crappy oil than plain bearings.

I bet your diesel engines had a thermostat that got them up to at least 180F. Our Zongs don't. The Zong engineers have most certainly decided that it was worth it to cut costs and eliminate a thermostat bypass circuit. The KLR engineers did the same thing. We can learn from the KLR owners because the cooling circuit is so similar and problematic.

[rjmorel]

All good points mentioned above. A lingering thought in my head thing is if we could buy a 190 deg thermostat to replace the one in our motors ,would that do what we want to bring temps up or am I missing the jist of the whole excersise? rj

[detours]

A 180 or 190 degree thermostat would get you partway there. You would also need to replace the fan temp switch so it doesn't come on until the temp you want.

But adding the bypass solves the problem of waves of cold coolant hitting the cylinder whenever the thermostat opens, thereby creating hot and cold spots in the engine.

The bypass mixes about 1/3 hot coolant with about 2/3 cold coolant to maintain a more even temperature and help the engine warm up faster on cold days.

[BlackBike]

Originally Posted by detours

A 180 or 190 degree thermostat would get you partway there. You would also need to replace the fan temp switch so it doesn't come on until the temp you want.

But adding the bypass solves the problem of waves of cold coolant hitting the cylinder whenever the thermostat opens, thereby creating hot and cold spots in the engine.

The bypass mixes about 1/3 hot coolant with about 2/3 cold coolant to maintain a more even temperature and help the engine warm up faster on cold days.

I kinda figured it was a dilution of temp thing but wasn't 100% sure. Thanks for the clarification. What is the cons for running higher temps? Is there any detriment to the motor? Everyone's ideas seem sound , but I'm just worried about high operating temps and the implications .

I would think a baseline fuel% would be in order for a test bike before and after the modification.

This has been a really interesting thread and am amazed at all the knowledge that has gone into this experiment.

[detours]

You hit the nail on the head about the fuel percent test. That's Huge reason for doing this mod. Reducing engine wear from uneven expansion due to hot/cold spots is the other.

I am not aware of any downside as long as the thermostat and fan temp sensor work properly. Also, the ratio of hot coolant in the bypass to cooler radiator coolant shouldn't be too high. If any of those 3 things fails, I think the bypass would overheat the engine faster than stock.

Others with more experience will hopefully correct me or add their insight.

[dpl096]

I'm sorry if I've missed reading this ... But has there been any word out of CSC or Zongshen about any warranty voidance issues to altering the cooling system during the coverage term?

[BlackBike]

Originally Posted by dpl096

I'm sorry if I've missed reading this ... But has there been any word out of CSC or Zongshen about any warranty voidance issues to altering the cooling system during the coverage term?

I think we all know the answer to the modification question.

[dpl096]

Originally Posted by BlackBike

I think we all know the answer to the modification question.

I'm figuring so as well... But hey if this works it might be something Zongshen might be interested in from these fellas!

[katflap]

thanks, I'm now on the mend, almost done with my man flu

Originally Posted by dpl096

As I understand it Kat has the better diagnostic capability/software? If that is so will he be testing the CR Thermo-Fix?

Not sure about me having the better diagnostic capability/software but I will certainly be testing it all as I go

I have a lot of the parts on their way so it shouldn't be to long before I can get started.

Firstly I shall be fitting a proper digital temp gauge using a koso adapter, as our built in temp gauge is of less than ideal. This will make monitoring the coolant temp much easier.

I'm going to use the 8mm self sealing barb (SST8K) in the bottom hose and hope its squeezing effect when attached in the hose doesn't impede coolant flow too much. As yet I haven't found a better solution.

The rest as previously described.

If all goes well ,I will then order one of the thermobob higher rated thermostats to complete the job.

I think that if I were you guys, living in the USA I would be seeking a solution with watt-mans thermobob complete kit as he quite obviously has a lot of experience with this.

Here in the UK I have to consider exchange rate, shipping & local taxes. That said, I have no doubt that if my experiments fail, I will be putting in an order for a thermobob.

[RedHawk47]

Originally Posted by SpudRider

I think the first solution is to install the OCS in the 'unofficial' position, as you have proven by valid experimentation.

As a secondary solution, I am going to replace the plug in the collection tube of the OCS with a bolt which is slightly loose. Before the collection tube of my OCS shrunk in size, it would slowly leak the collected fluid. I wish to reproduce that slow leak, so I don't have to check the tube all the time. Ron_B in Alabama has added a fuel petcock to the bottom of his collection tube.

http://www.chinariders.net/showthrea...t=16492&page=4

The plug in my collection tube was leaking, and making a MESS on the bike, and probably on the tire. Installed a fuel petcock; problem solved.

Meanwhile, with the OCS in the new "official" orientation, the collection tube fills up on a day's ride.

[rtking]

Originally Posted by RedHawk47

The plug in my collection tube was leaking, and making a MESS on the bike, and probably on the tire. Installed a fuel petcock; problem solved.

Meanwhile, with the OCS in the new "official" orientation, the collection tube fills up on a day's ride.

I am experiencing the same, Redhawk. I put my OCS in the "official" position and did a 2 hour ride this morning. I now have 1/3 of my collection tube filled. In the unofficial position, it would remain bone dry. Later this afternoon, I'm flipping my OCS back to the "unofficial" position.

[rideabout]

I'm a little confused, isn't it better to have more fuel vapor condense and drop into the OCS tube rather than have it remain in the crankcase? Maybe it just gets burned with the intake charge instead when upside down? Sorry, I know this has been discussed at length......

[Jay In Milpitas]

Originally Posted by rideabout

I'm a little confused, isn't it better to have more fuel vapor condense and drop into the OCS tube rather than have it remain in the crankcase? Maybe it just gets burned with the intake charge instead when upside down? Sorry, I know this has been discussed at length......

It's a coin toss. Folks have reported success for both positions.
Because it works in that way for some folks, they tend to preach that every bike should do it that way also. Do what works for you.

Mine is in the "official" position and I seldom have build up. It was worse before I noticed that a couple of the clamps that hold the tube to the air canister were squeezed too tight, restricting the breathing.

[detours]

Originally Posted by rideabout

I'm a little confused, isn't it better to have more fuel vapor condense and drop into the OCS tube rather than have it remain in the crankcase? Maybe it just gets burned with the intake charge instead when upside down? Sorry, I know this has been discussed at length......

As Jay said, it's kind of a coin toss. We simply don't have enough data to say for certain which orientation is better.

However, in my opinion the unofficial orientation improves the vapor flow to the airbox, burning fuel vapor in combustion instead of condensing it in the catchtube. I say this because the oil temps are the same, which 'should' evaporate the same amount of fuel. Less fuel in the catchtube 'should' mean more vapor in the air intake.

But without doing a lot of oil analysis, I can't be certain which is better.

[rideabout]

Thanks Jay/Detours for the info