93 Honda Civic LSi D15B2 Coolant leak

Hi people - after successfully changing my manual transmission oil
yesterday, today it was the turn of the coolant. The car has been
running fine with no leaks or heat problems, the coolant was just due
a change.

So I flushed the system with some chemical cleaner stuff, reflushed
with water then refilled with coolant. Being responsible I took it for
a drive to dispose of the old antifreeze at the chemical recycling
place... but when I got out of the car the new coolant was literally
flowing on to the floor :-( Luckily I don't live far away so managed
to get it back without overheating the engine - when I looked
underneath the coolant seemed to be coming from the water pump bleed/
weep hole.

I'm hoping that it's just air in the system? I hope it's not it's any
type of gasket failure since it has been fine up to today....

Any ideas greatly received.

 

I once did a rad flush on my 85 nissan 200sx. I was fighting leaks for the
next 3 months. I never recommend anybody use rad flush on an older vehicle.
It gets rid of all of the gunk thats holding the cooling system together!

If your water pump is leaking out of the weep hole, replace the pump because
the bushing is shot.

I would then do a pressure test on the system to find all the other leaks.
Heater lines, heater core, and anywhere there is a clamp to metal surface are
culprit. Also, once the system is empty, I would flush it with WATER ONLY to
ensure you got all of the rad flush out of the system.

t

 

I once did a rad flush on my 85 nissan 200sx. I was fighting leaks for the
next 3 months. I never recommend anybody use rad flush on an older vehicle.
It gets rid of all of the gunk thats holding the cooling system together!

If your water pump is leaking out of the weep hole, replace the pump because
the bushing is shot.

I would then do a pressure test on the system to find all the other leaks.
Heater lines, heater core, and anywhere there is a clamp to metal surface are
culprit. Also, once the system is empty, I would flush it with WATER ONLY to
ensure you got all of the rad flush out of the system.

t

 

you need a new water pump - that seal is not repairable or replacable.

got to be /VERY/ careful using that chemical cleaner. this is an
aluminum block - the caustic chemical in the cleaner dissolves metal.
better to simply flush using fresh water. when refilling, use only
distilled water to dilute the antifreeze. use a high quality long life
fluid - the cheap stuff contains silicates which cause problems on hondas.

finally, when flushing, it's best to open the drain plug on the block as
well as the radiator. otherwise, chemical containing] fluid remains in
the block, much as water remains in the bottom of a toilet.

 

I am not optimistic air in the system is the problem, but
for the record, did you purge the system of air per the
manual's directions? This will include running the engine
until the rad fan comes on twice. On my 91 Civic (same
engine), getting the engine temp high enough in (mild)
winter takes 40 to 60 minutes.

 

I think I have got rid of all the cleaner now since all the new
coolant has run out of it and I've been pouring water into the system
whilst the engine is warm... and trying to 'burp' it of air bubbles at
the same time. I figure if I manage to get the water to stop leaking
I'll try coolant again.

 

Did the coolant again to the book letting it warm up lots (fan went on
and off 5 times) - but it still leaks out of the water pump weep
hole :-( - thinking it's probably the water pump gasket... Does anyone
have any views on this "stop leak" fluid stuff? Cheers!

 

won't work - the pump shaft seal had gone. you need to replace the
pump. ~$50.

 

typically, you replace the water pump whenever you replace the timing
belt, because they don't last forever.
and might as well replace the timing belt now that you are going to
replace the water pump.

 

with reference to the timing belt/water pump job i talked about last
post; it's likely that either the pump wasn't replaced when the belt
was, or the belt wasn't replaced either. either way, your best bet
unless you are selling the car real soon is just replace both now.