Lance Duke Touring 250 cooling By billg (Read 5,538 times)

[cyborg]

I'd be concerned ( read worried) if the oil temp is over 230-240 on a liquid cooled I would think,,, more for an air-cooled but that's a different situation,,, I'd run with Rich's suggestion but with a little distance from the Jed Clampet thermometer routine and get an infrared temp gun,,,,harbor freight sells them dirt cheap and they are extremely accurate most are +- less than half a degree,,, afterall this is the 21st century and anyways granny would get really pissed if you used her turkey thermometer,,, she is pretty good with that double barrel

[Bashan]

It's not Granny bonehead, it's Martha Stewart.

By the way, for all of you lurkers thinking we're being ugly with each other when we call each other names, that means we're great friends. It's the Scooter Doc way. So join up and get abused! You pin heads!

[cyborg]

It's the dicotomy of life,, we have to make up for the stiffs over on MV ,, so there will be balance in the universe,,,,

[billg]

I picked up a laser thermometer at Harbor Freight on sale for 26 bucks today.  It will be a few days before I can get the test done.  Some rain's rolling into Southern California today.

I will have to remove the bottom skin for the test so I can check radiator temps.  I still think I have some blocked tubes in the radiator and the laser thermometer is just the thing to find out.  I bought this scooter with less than 1300 miles on it from a second owner.  Apparently the previous owners didn't know about replacing all the fluids.  You wouldn't believe what I washed out of the cooling system.  I had to drill out the carb heating (cooling?) circuit which was plugged tight.

[Alleyoop]

The carb heating(cooling) really is only for the ENRICHER for COLD STARTS but your in CA so you do not need any heating. Actually those are OBSOLETE and on the newer scoots they are not connected but the carbs still come with the connectors held on with one screw to the carb.

Have you checked the pump maybe the pump is shot and not pumping the fluid.
Alleyoop

[cyborg]

I was reading another thread on another forum researching the cooling probs with another member here on this forum and the OAT or HOAT coolants they were useing coagulated after 12-16 months causing plugged radiators coolant galleys you name it,,,i think you are correct in assuming the rad is partially plugged,,,,hey where are you in so-cal i'm in the westlake /thousand oaks area just north of Los Angeles

[billg]

I'm in Santa Ana in Orange County maybe 40 mi. south of LA.

[billg]

I've had the pump cover off and it looks OK.  A twist of the vane confirmed the pump shaft is OK.  I doubt the fan would ever come on if the pump didn't work as the fan switch is at the bottom of the radiator.  If there were no circulation hot coolant would not reach the radiator, seems to me.

[cyborg]

I say you have a few rad channels plugged with the jelled coolant,,,

[jct842]

That laser thermometer will be able to find a blocked tube easily. I use mine to check temps on fish tanks, outdoor fish tank, cooking surfaces, walls and ceiling for hot spots (insulation problems) and of course engines. Then there is the wood stove. Mine is the tool from harbor that I have used more than all the rest of them put together!

[Bashan]

How about this? Pull the gauge sensor and hook it up with jumpers with the + lead just out of the water. Run the G/L to the gauge. Frame ground the other lead. Turn on the key and heat the water. The gauge should work just like if it's in the bike.

[billg]

I took my radiator apart and rodded it out.



It had a pinhole leak where the tubes joined the end plate. You can see from the internal rust pattern of the radiator in the foreground that it had been running about 3/4 full. I fixed that leak and the tiny one at the tube coming out of the engine & going to the carb, a cooked hose end probably.

I had it out the other day in 95 degree heat in town. The temp pegged again. Arriving home I immediately got my temp instrument and read 210 F at the crank case. My guess is the cooling system keeps up until the oil temp rises and then it's peg city for the duration.

Either the cooling system is inadequate or there is a blockage somewhere. I'll be checking the hoses next. Other than that, I can't think of anything I haven't checked except the temp sensor.

[billg]

Oops! Wrong pic. Here's the radiator apart.

[billg]

This is an attempt to get an upload of better resolution.

[billg]

Another attempt for better resolution using ePhoto Bay.