Blowin my load

[forget]

g'day all
i have a problem ,my 1990 rr classic 3.9 keeps blowin its load (from radiator)
i keep fiillin er up wiuth the approppriat fluid and it keep unloading itself back out thru the cap on the expansion tank
i have tried filling up from the highest points ,even jacked up the drivers side and filled but it keeps emptying itself,and developing airlocks in the top rad hose.
one time when i filled it i took off all 3 caps and tried to fill,and started engine and instanly it started to blow all its fluid out thru the top filler neck(brass fitting next to manifold) \
so i just turn engine off and fill thru the radiator top plug and the expansion tank
but it just keeps getting these bloody airlocks and blowin its **** everywhere,changed thermostat to 88c(same as what it had)and still no difference had ther rad flushed about 6 months ago also
so i want to know how the best way to check the water pump !!!
cos i am pullin my bloody hair out over this it has been a persistent problem for about 2 years and i just cant track it.
anyway any help would be gratfull,
thankyou everyone.

shane

[Slunnie]

Not a head gasket?

[forget]

nah no sighns of water in the oil at all checked both the oil and cap
been wondering if it could be a slipped liner though
but i think i will replace water pump first

[slug_burner]

You don't have to have water in the oil to have a blown head gasket.

Pressurisation of the cooling system is a classic head problem symptom. Suggest you have a check for combustion gases in the cooling system. Simple enough done with some sniffer/gas analyser.

[mike 90 RR]

g'day all

one time when i filled it i took off all 3 caps and tried to fill,and started engine and instanly it started to blow all its fluid out thru the top filler neck(brass fitting next to manifold) \
so i just turn engine off and fill thru the radiator top plug and the expansion tank
but it just keeps getting these bloody airlocks and blowin its ****

shane

Hi Shane
Try the following ......

Now park the car on a hill with the nose of the car facing UP ... car ramps will do


On top of the right hand (drivers side) rocker cover is 2 metal water line tubes .... At the rear of the tubes is where the 3/4 rubber water heater hoses are connected

Disconnect the hose's .... and with a new piece of hose ...... loop and connect the 2 together ..... This will bypass the heater box in the cabin under dash

Take the radiator top bung off
Take the expansion cap off
Fill with coolant thru the "fill bung on top of the rocker cover"
Put bung back in ..... And MAKE SURE that the water is full // NO AIR in that tube // when you put the bung back in

Now fill up the radiator till its full & stays full (add water to expansion tank .. just fill it)// leave radiator bung out // leave expansion cap off

Start motor // watch water levels through radiator bung hole // fill through bung hole .... till engine is warmed

If the water level drops fast ... stop motor and fill .... repeat procedure




Water pump shot? ... if it isn't leaking ... I would say not likely
There is a art to filling & getting the airlock out of these motors ... but if yours has been going on for 2 years .. then I would be thinking of other problems :(

Let me know how it went ... as I have one more "trick up my sleeve" for you to try .. before drastic measures are required

Mike

:)

[forget]

thanks for the reply mike ,i havent bypassed the heater yet but am going to if if lets me down again

i have been doing quite a bit of reading on the forum about this and decided to do a comp test tonight and came up with these figures


from the back
140 140
140 135
150 140
148 145
from the front

i dont think there is to much wrong from these figures, although i would like to get my hands on a leak down kit for a couple of hours maybe
i have topped it up again and will see what happens,but i think on previous accasions i have overfilled the expansion tank,so this time i have only half filled the expansion tank.
fingers crossed:angel:

[mike 90 RR]

i have overfilled the expansion tank,so this time i have only half filled the expansion tank.


Good to have the expansion tank at it's normal level of 1/2 full when cold



Also ... try a 82 degree thermostat with a "new cap" for the expansion tank

Never do a fill of coolant at the radiator bung .... only minor top ups

Always do a major fill at the bung on top of the R/H rocker cover ... with the car facing uphill on a slope (car ramps are good) ... and the heater box in the cabin turned onto full heat (Hot) ... as this opens the valve to allow the coolant and the air to pass through

Hope it helps

Mike

:)

[forget]

only filled the expansion tank up half way this time !

just been for a drive and it got hot again but this time has not blown all the coolant out this time ,mind you it didnt get real hot ,but probly one thing i should have said at the start is that it does get hot,to about 3/4 on the gauge before it blows its load,had it pressure tested a few weeks back and everything fine so i might wait till the radiator shop opens up and see if he has a sniffer/gas anylizer and get it checked.
but i am sus on the water pump though !:angel:
thanks again:)