Just bought a 91 plymouth acclaim and we think it has a blown head gasket and maybe warpped head they told us it would cost around 1500 to fix it but don't know the size of motor it is a 4 cylinder

You bought a car with a failed head gasket or crack in the block
or cylinder heads,that is why it was gotten rid of

The A/C System probably failed years ago,not related

the cooling fan has problems--shud go on without reving--the coolant sensor probly bad--du a scan or data stream on vehicle to confirm--mite take out sensor and testit

That can be caused by a number of things. It could be a bad engine coolant thermostat. It could be low engine coolant due to a leak. It could be a clogged-up heater core. It could be a bad water pump. It could be a blown head gasket....the problem needs to be diagnosed before anyone can tell you exactly WHY you have poor heat. (Although many may try to GUESS and tell you to just start replacing parts without any diagnosis.)

The torque specs should be the same but I have never heard of this before. Make sure you have the head checked for cracks & checked for warpage. It may need to be planed. Be sure to use a top quality head gasket. Good luck!

The head gasket itself is not much money. Any backyard mechanic can replace it. If the engine has an overhead cam , it's a bit more involved , however , I have purchased cars specifically because they needed a head gasket , and the owner was quoted big bucks to have the job done. I spent one afternoon doing the job and had a good car cheap.
A 92 acclaim is not worth a whole lot to begin with , so I would advertise it pretty cheap just to get rid of it. Ask around , maybe the son of a friend of a friend will fix it for you cheaply.
A repair shop will charge you several hundreds of dollars to do it , but I could do it for myself for about $60

check the coolant to see if oil is mixed in it if so the head it cracked or head gasket is blown

diagrams (actually pics) are available online at autozone.com/repairguides, or other such sites. get yourself a haynes or chiltons manual @ ebay or any of the parts houses or maybe at your library...it'll save you big bucks....hope this helps

Could have air in the system, bleed air at the manifold, there is usually a small screw in the intake manifold....

what make you think the gasket has gone, did car overheat?

Honestly... If you are really not that good at mechanical issues you probably should take it in... Not to be mean but the head needs to come off in a bolt sequence and reinstalled in a bolt sequence with the correct torque... The passenger motor mount,exaust,wire harness,valve cover,head boltscoolant hoses,throttle cable and many more items need to be removed......Also NOTE:... slip and tuck head gasket jobs are NOT advisable and ussually result in doing the job twice over..... The heads have a tendency to warp and also crush in the gaskets over time....The head should be checked for warpage. Also a good time to do the valves and replace seals.......in the end if you are not experienced and do not have someone around that knows aboput the job at hand you may want to have the job done by a tech... For fun grab yourself a Chiltons manual and read through........

Good luck

Robb