Please help!!! Trying to pin point problem

[dahc240]

I have searched and searched...and havent found out exactly what my problem is? So here goes I just bought my 3rd s13 with a KA24de and after a long drive when I shut it off and a few seconds go by it starts to boil water back into the reservoir it never overheats and I cant tell if its leaking water anywhere....I have already replaced the cap and still does the same thing. Im thinking it might be the water pump B/C no oil in water so hopefully its not the headgasket. Oh and it only has 115K on it

Any ideas would helpThanks in Advance

[240sxmech]

conduct a block test to rule out a blown head gasket or not. Also check to see if you have flow when tstat is open.

[B33FST3W]

Have you done a compression test yet? http://www.tegger.com/hondafaq....html This site says its either a bad radiator cap or a blown headgasket. GL and I hope its not your headgasket.

[tonynalli]

^^^A compression test is NOT the proper way to determine if you have a blown headgasket. If you have major loss of compresion it will show that, and you can determine it to be a head gasket. I did a compression test on a motor once and there was only a few psi difference across the board. But whe i hooked that block tester on the radiator, i showed it had a blown headgasket. Dont waste you time with a compression test, do it once and do it right with a block tester.

[B33FST3W]

^^^A compression test is NOT the proper way to determine if you have a blown headgasket. If you have major loss of compresion it will show that, and you can determine it to be a head gasket. I did a compression test on a motor once and there was only a few psi difference across the board. But whe i hooked that block tester on the radiator, i showed it had a blown headgasket. Dont waste you time with a compression test, do it once and do it right with a block tester.

The "proper" way to do it (or at least the way I was tought when I was a mechanic) it to take an emission sniffer (I dont know the name of it but its the thing you put up the tail pipe) to your radiator and see if it picks up any hydrocarbons in with your coolant, but I am assuming he doesnt have access to one of these. And because he is a friend of mine, I know he does have a compression tester, so therefore I told him to do a compression test.

[dahc240]

I did a compression test and got 180 across the board. Changed the radiator cap and still does the same thing...So im still up for any ideas

[B33FST3W]

is it possible that your radiator is warped right there and not letting the cap get a good seal? and BTW its not the headgasket because it did it when the car wasnt running so we can cross that off the list. If you want, on thursday, we can go to the shop I used to work at and use their pressure tester and pressurize your coolant system and see if we see any leaks. When the car is hot, what is the coolant level at?

[240sxmech]

what type of cooling fan do you have on their? the stock with a fan clutch or have you changed it to an electric.Like i said before check to see if you have flow when you hit operating temps.Either a bad water pump or a bad tstat.

[240sxmech]

Also when it boils over can you fell it bubbling in the radiator hose if it isnt bubbling in the hose then your not overheating you just have a cap sealing problem like your friend said .Good luck