so i over heated today

[christopher0227]

my thermostat went out today i have 2 240 sx engines a single cam and duel cam both with new thermostats can i use them on my l20b?

[motavated]

Well just search it up at autozone.com. Look up the part for the l20 and then the Ka24. Same part number for both then its the same part pretty much.

[banzai510(hainz)]

standared 54mm stat will work. 160 180 or 195 I would get the 160 myself. if your Rad is a 3 core get a 180 or 195 in winter

 

Buy a new one!!!!!!!!!!!!I insist!!!!!! Or buy the ones that when they FAIL they go open!!!!!!

[Braden]

anybody have a part numbe ron a 160??? all i could find is a 180

[banzai510(hainz)]

Most parts stores carry and Stant brand stats around here.

 

just look for a 54mm size then look for 160. Thats how I do it.

 

Most Datsun book list 180deg stats or higher.

 

In theory the Hoter stat is supposed to stay closed longer before letting the water out to the rad too cool it. So the water in the Rad will have more time to cool down.

So if you live in a really Hot place the 160 might still not work till you have a bigger Rad.

Lucky latter 620s had a 3core rads ans still can get them faily cheap. Unlike 510 rads.

[datzenmike]

Don't cheap out get a $12 one. 180 is fine and close to factory and if your cooling system is in good order shouldn't be a problem. If you have a modified motor 160 might be better but it won't be opperating at optimal temperatures.

[]2eDeYe]

The temp rating is usually part of the part #.

[christopher0227]

so its not my thermosat i boiled it it opens and shuts fine next is to buy a water pump and see if thats it

[banzai510(hainz)]

I dont thinks its your water pump unless all the vains rotted off and it isnt pushing water.

Most time the stat is closed enough just to recirculate water in the block(if that) then it lets it out.

water pumps themselves dont go bad its the bearings/seals in the bearing that goes bad thus causing a leak. or if real bad just fall apart and wipe out a front timming cover.

 

ck to see if you lower hose is soft when you rev up the motor. It can collapse.If so relace the lower hose.

 

 

Are you using/losing water? and do you see a leak. or do you see maybe water vapor comming out the exhaust?

 

another way to ck this is pull out the stat. run it and see if still over heats or really overpressurizes then you have a blown head gasket.

My 521 truck My headgasket was bad but was sucking water IN to the piston thus having slight vapar out the exhaust.

[datzenmike]

Also check for loose belt or glazed. Glazing can cause or be the cause of the belt being highly polished and so smooth it will slip when revved.

Check for obstruction to air flow through the rad caused by leaves, dirt or a plastic bag.

Do you have a fan shroud? This will increase the fan efficiency.

Do you have a clutch fan? Clutch fans (or any fan) are most important at lower speeds where the vehicle isn't moving fast enough to push air through the rad. To check, (engine off) try to turn the blades. If the viscoud silicone liquid has leaked out it will turn easily and you may even be able to spin it. A good one will offer firm resistance to turning by hand. A loose slippy clutch fan will not move much air at idle or low speeds and it will run hot.

Remove rad cap and look at the vertical cooling tubes inside. If crusty with deposits it will have reduced flow and run hot.

[christopher0227]

no clutch fan previous owner installed a electric fan runs fine till it gets hot also has aftermarket temp guage

[datzenmike]

An electric fan should not be on until needed for extra cooling. Having on all the time is the same as having a regular fan.They were never designed to last when used all the time. Get a thermo switch and relay and give it a rest.

[alex843]

I was having the same problem on my truck. Found the radiator was dirty, also had some pin hole leaks in it. Had it cleaned and repaired. Actually the whole cooling system was dirty, not sure what was in their look like calcium deposits and other junk. The truck had been sitting for a couple of years when i got it. I flushed the whole cooling system by disconnecting the outlet hose on the block. Then i was putting fresh water into the radiator while the truck was on and catching the water that was coming out of the engine until it looked clean. That worked pretty good until my radiator rotted all the way through and I had to replace it.

[hang_510]

Found the radiator was dirty, also had some pin hole leaks in it. Had it cleaned and repaired. Actually the whole cooling system was dirty

i check this before replacing the WP. (BTW: i have 2 new Jap made if you need 1)

[christopher0227]

ok ill check the rad then flush the cooling ill keep you guys updated thanks

[Buzzbomb]

standared 54mm stat will work. 160 180 or 195 I would get the 160 myself. if your Rad is a 3 core get a 180 or 195 in winter

 

Buy a new one!!!!!!!!!!!!I insist!!!!!! Or buy the ones that when they FAIL they go open!!!!!!

 

Great advice about the "hotter" T-stat for the winter w/3 core rad. I replaced my 180 T-stat with a Beck-Arnley 195 when I did my head gasket on my L20b, and it made a huge difference with the way the heater works. As a matter of fact, my truck really doesn't run any hotter in the Summer now than it did before. If I have a long haul up a hill in 90 degree heat, I might get a needle width or two beyond the middle, but that is pretty much it. Otherwise it hangs around the second line on the gauge and the middle of the gauge.

 

 

I flushed the whole cooling system by disconnecting the outlet hose on the block.

 

You can also disconnect the heater hose connector at the back of the head and flush the core out. It's part of the cooling system too. An old hot rodders trick that I've used is when it starts to creep up on the gauge, put the heater on.

 

For the original poster, how old is this thermostat? I would take Datzenmike's advice and get a good quality thermostat to replace your old one regardless if yours "tested" alright. It's worth it if it's all apart and you don't know how old the one you have is.

[datzenmike]

I wouln't boil water for $12.