this is for FI TB loyale and since I have the coolant and leakdown tester, I was asked by a friend to check the cooling system, ..once the coolant tester was ready and the rubber hoses finished expanding we let it sit there for 1hr and the needle did not move a hair ...as it is being pumped up we sprayed soapy water and found nothing...new plugs and rad cap were installed plus 110 psi into the cylinders trying to find any signs of leakage..none.. also for another 1hr we let the car run at 1500-2000rpm in the driveway and it produces white smoke, and water dripping from the exhaust pipe... but every once in a while it will stop momentarily, and once it is up to operating temps 200-210F it just stays at the temp and the rad cap does not open at this point..my question is..after about 45min the smokeing tail pipe stops and is completely dry..yet coolant needs to be added every time this test is done (3times)..spark plugs remain very clean.. what is cracked that would open up when heated..

Edited October 26, 201114 yr by Petersubaru

Sometimes you need to let the car sit overnight or many hours pressurized. White smoke I cant judge, but put your hand up to the tail pipe and see if it smells like antifreeze or funky.

 

Try a vacume gauge reading and see what that comes back as. When you check the plugs is one more cleaner then the others?

 

You may still have a sneaky external leak which sometimes calls for a dye and blacklight to find. You can be loosing coolant from a manifold gasket.

Sometimes you need to let the car sit overnight or many hours pressurized. White smoke I cant judge, but put your hand up to the tail pipe and see if it smells like antifreeze or funky.

 

Try a vacume gauge reading and see what that comes back as. When you check the plugs is one more cleaner then the others?

 

You may still have a sneaky external leak which sometimes calls for a dye and blacklight to find. You can be loosing coolant from a manifold gasket.

...sorry I did not mention it..new intake subi gaskets were installed and throttle body rubber base seal.. the tale pipe does not smell of coolant and all the plugs are identical in appearance..I will hook-up the pressure tester for all night and remove the exhaust from the manifold ..maybe I will find something..also I will probably remove the throttle body again and seal off the coolant passages to it since those rubber base seals are similar to the micky mouse ears of the oil pump, being very thin in appearance..11 yrs ago I took my '86 up to Alaska and back with cracked exhaust ports, once the engine heated up it sealed itself but every morning I had to add some coolant...however I did pass a lot of stranded people with coolant problems in the middle of BF no-where.. almost forgot, the vac gauge reads steady at 20...

Thats what i am leaning towards, is a crack someplace allowing water to escape. When you let the pressure sit overnight remove all the plugs and crank the engine, just in case coolant has leaked into the cylinder, hydrolock aint pretty.

Thats what i am leaning towards, is a crack someplace allowing water to escape. When you let the pressure sit overnight remove all the plugs and crank the engine, just in case coolant has leaked into the cylinder, hydrolock aint pretty.

..I am familliar with hydrolock..my first experience with fel-pro intake gaskets..

I thought I would post a report, so after 7hrs of having the coolant under pressure it dropped less then 1.5 psi ..from 16psi to slightly under 15psi and one tablespoon of coolant added...for me it is like finding a needle in the haystack ..anyway I hope the owner will spring for a dye tester and if so i will again post what I found..so simple yet difficult..

a follow-up ...the coolant tracer dye was eventually bought and the leak was found to be "only inside" at the base of the TB..very small leak on the drivers side and fouling up those 2 plugs..at first you would think something else is the problem like a HG needed etc and although a new rubber TB base seal was initially installed only added to the confusion..apon inspection and for whatever reason the whole intake unit is twisted and .010 had to be machined off where it meets the cly. head, ... also decided to close off the coolant passage to the TB rather then resurface (to expensive)... all is good...