I can not keep my mojave from boiling all of it's radiator fluid out. It only takes a 5 to 10 minute ride to have the radiator almost empty. This problem started after I put a clamp-on K&N filter on. I have a Big Gun exhaust, clamp-on K&N filter, Wiseco piston, Cometic gasket set, 152.5 main jet, and just replaced my rings because this overheating fryed my rings. I have checked my water pump, removed the thermotat from the head, am using Water Wetter, and have made radiator shrouds to direct more air into the radiator with only minimal results. Any help would be apreciated.

 

Ugh! Got me bro! Is your fan working at all? Have you tried using a different antifreeze? I'm sure some of our fellow Mojave brethren will be able to give you some advice! Goog luck man.

 

Try washing your radiator out with water. Something might have gotten in it and plugged it up. Did you get a new thermostat? MAke sure all the hoses from the radiator aren't plugged also.

 

I have wired my fan so that is stays on as long as the moter is running. I have used Peak and Texaco antifreeze and that didn't make a difference. I flushed the radiator with compressed air and water and it didn't change either. I took my head off to see if any of my ports are clogged and didn't see any clogged but I flushed them and blew them out with compressed air just to make sure there wasn't something in there I couldn't see. I have not checked the hoses yet but will do that tommorow after I get my motor back together. Also, I did not get a new thermostat because I believe no thermostat would give more flow. Thanks for the help.

 

I know you said you checked the water pump, but it may not be working as it should. Go to the hardware store and pick up some clear hose that is the same size as your radiator hose and use it in place of at least one of the rad hoses. this way you can see if you have proper flow and if there are any air pockets in the system. Once you have the problem fixed, put the original hoses back on.

I would also replace the thermostat, ruuning without it can speed the water flow up to the point that it is not in the rad long enough for enough for heat transfer and therfore not cooling enough.

If the engine is apart now be sure to check the head surface. Make sure it is flat and uniform using a machinest straight edge. Examine the old head gasket very closely looking for any minute sign of compression leaking into the water jacket.
I have found overheating to be a fairly rare occurence on Mojaves. And the hardest problems to find always seem to be caused by the simplest things, I guess it's just one of those things like washing your car and then you know its gonna rain.

 

I put it back together today but didn't get done until about 7:00 so I could only test ride it for about 5 minutes. In that short time it didn't show any signs of overheating. I may not have riden long enough to overheat it but it didn't overheat when it normally would. Tommorow I will get a chance to test it for a longer time and will defanitely try using clear radiator hose. If I still have problems I will try getting a new thermostat. Thanks!

 

One other thing, with all your mods are you jetted correctly? If you're running lean, you're going to heat up pretty quickly. I used to own a mojave and it was pretty picky about jetting. I noticed that you mentioned a clamp-on K&N. Clamped on directly to your carb? If you bypassed the restrictive mojave air filter housing - you will definitely need to rejet.

ogre

 

Make sure you put the hoses back on the water pump in the correct locations, it's very easy to get them mixed up because they cross over each other. I speak from experience, it overheats with them crossed. I still can't believe I did that, oh well atleast I only rode it once. Live and learn.

 

You are too late jeffksf. My idiot self swithched the hoses on the water pump when I put new rings in. I just fixed that last night and tried it today. It helped a lot but my radiator still blows out about 1/4 of it's water after a 10 minute ride. I also tried putting my thermostat back in and that also helped but didn't cure it. I figure the thermostat didn't work when the water was flowing backwards. I am now using Havoline coolant and Water Wetter which also helps a little. As for jetting I am running a 152.5 main jet, a 38 pilot with fuel screw 3 turns out, and a 1/4" spacer under the stock needle. I may try going up to a 155 if i can not figure the problem out by satuday. My flow is also verry good now that I got it flowing in the right direction. I realy apreciate all of the help!

 

I am running the wiseco piston, ported head, supertrapp exhaust, and modified black box and my bike loses water too, I removed the overflow bottle and just top off the radiator before every ride. I've heard from others that it's no big deal. I run in the summer w/o the thermostat and put it back in for the winter. Another tip is to drill a hole in the plastic right above the radiator cap and use a small funnel with a hose to add water. I also installed a pro design supercooler, I didn't notice any difference.