one hot motha F**ker

[bmxruler4130]

lately my 240 likes to overheat. it only happens when im on the high way or when i rev. the car for a little while (at about 3-4 grand). the coolent is full, but i might be old. and the radator looks fine. all the hoses are good too. mabe a water pump? possably a head gasket? but it runs fine.. just a little rough but not out of the ordinary.

[yellow_jacket]

Sounds more like a plugged radiator or bad thermostat. Head gaskets usually overheat almost randomly. Water pumps usually make a lot of noise when they start to go bad. A radiator shop will be able to flow check the radiator for you for about $45 and if it is bad that money goes towards a new metal one that they sell.

[Silvia007]

Here's what I think is going on, there's a air pocket circulating in your cooling system. First off, take off ur radiator cap. Keep your motor rev'ed to about 3k and just wait, it'll over heat and when it does, ur thermostat will open all the way allowing lots of water to run out... becareful as lots and lots of coolant might blow out from the opening where the cap goes to... and once that happens and calms down, fill it up with coolant and ur set. If it still overheats, repeat the process. I work at Jiffy Lube and we have lots of cases like that. Hope that helps.

[yellow_jacket]

That is precisely why Nissan put a bleeder on their cooling system.

[bmxruler4130]

where is the bleeder.. and will useing the bleeder get rid of the air bubble?

[Silvia007]

bleeder is too small to rid big air bubbles. it'll take some time but bleeder to me is too slow. TO find the bleeder, follow ur top radiator hose all the way from the radiator to the block, right where the hose connects to the aluminum of the block, the bleeder should be a zerk or fitting with a 10 mm bolt.

[signal180sx]

does the bleeder leak out fluid as well?

[bmxruler4130]

cars all fixed... turns out it was just the belt to the water pump slipping