what is the cost and difficulty of replacing my thermostat on a 87 bII 2.9.? I think it is stuck since I am over heating and my lead hose is hot to the touch.

 

Cost should not be much $10 for a good stat $2-$4 for the o ring.to replace is easy fllow the top hoes to the engine that is where the stat is at 3 small bolts hold the housung to the engine,10mm I think,be carful taking them out the will brake real easy after you get the housing off you will see the stat/ Instal in the rev.order. Hope this helps.

 

If it were mine,I would let it cool off,then remove the t-stat,clean both sides of the mounting surface,put a bead of silicon on the housing and reinstall it,refill with fluid and go for a ride.If it does not overheat again the I would go ahead and get a t-stat,but if it still overheats then I could rule the t-stat out

 

Thats right but why do it twice if your going to tare it apart,I would do it just once.I lazy , I dont like doing things twice, thats just me.

 

Is it necessary to drain the entire system before removing the stat? According to Chilton's, you should.

 

I would at least drain the radeator,you will still have some come out of the stat houseing,[NOT MUCH]

 

You have to get the fluid level below the t-stat housing anyway so yes just open the petcock and let it drain.And the reason I suggested doing this is,this is a 2.9l,and they did have a problem with headgaskets,so I would hate to see someone install a new t-stat and new anti-freeze just to drain it back out.The t-stat is so easy to yank out anyway.

 

You dont hafta drain anything. When you pull out the thermostat some coolant will spill but thats it. Then just put the new one in and youre set.... you wont lose enough coolant to worry about putting more in. But since you dont know for sure if thats the problem, i would just top it off anyway. Last, if you care about the mess you just made from spilling the coolant, hose it off real quick.

 

thanks everybody! I will let you know how it goes!

 

When was last time the antifreeze has been changed? If it has been over 2 years & 24000 miles I would flush & drain the system & add new antifreeze after you change the thermostat. You only need one gallon of antifreeze to get it to 35 bellow. Dirty sluged up cooling systems tend to over heat. I have been using the Prestone back flushing kit for years 7 they work grat on the BII.

 

I guess I should drain and fill after I replace the thermostat since it has been about 30k miles since the last one! I have never done it myself, it is difficult? Just drain the radiator petcock thing and then fill it up? Is there anything else to it. Bare with me please, I am new to self repair/maintenance

 

By a Prestone back flushing kit ($4.50)that you connect into the heater hose.
That way way you get the yuck out. Just draining it will not get it out. good luck.