Mystery Coolant Leak

[JOSH0315]

I've got a slow coolant leak and dont know where its coming from. I found coolant on the bottom of the bell housing, there is no sign of any coolant any where else, i've tried to follow the coolant but it just seems to appear there.
I've recently rebuilt the motor and all hoses have been replaced and i checked them for leaks. The heater hoses are fine and not leaking either

Does anyone have any idea wat this might be

[ranger88den]

Clean the engine and trans then try some coolant dye. Follow directions regarding driving vehicle and detection light. Also might try pressurizing the system. Good luck

[jtgh]

you didnt say what motor, there are like 8

but if it is like this 8v , this will help
block is same on 16v.

id have a car HOT, and full pressure under RAD cap, 12.5psi (normal)
then with a mirror and running, look behind head.

look careful.
there are no freeze plugs on rear of head or block so that is not it.

my guess. it s comming from intake gasket bad or cooling tubes,
but you didnt say what engine so i can help too much.
fill out signature and get far better help.

[jtgh]

as you can see there is a water jacket clean out plate on block
and it rusts thru, leak.

it is very think , so it would take serious coolant abuse to do that.

[TheZuke!]

Just my own observations...
When I changed the water pump last week,
I noticed it had a dried coolant trail from the
lower drip hole. I also have similar crud
around the thermostat housing and upper
radiator hose at the radiator.

[jtgh]

hi thezuke

the gasket and hose are weeping.

hey ,zuke you just send me parts?

[JOSH0315]

Its a G16A 8valve

When you say coolant abuse i'm not quite sure what you mean

It has never been overheated and coolant has always been a nice green and kept at the top.

At the bottom of the bell housing there is a small squareish hole it appears to be dry, if it was leaking from that plate would it come out there

I've attatched two photos in the second pic there looks like there is a hole but cannot really see anything in the first.

[CodyJ]

Remember that it will run from a higher location and usually to the back...
Recent rebuild -- did you replace the water pump (tell us brand or that its cheap brand)?

These things like to leak sometimes randomly and cause issues like this... I had a problem and thought I blew headgasket after parking it hot one day but turns out to be the pump failed.

[jtgh]

as cody said, down and back it all goes.
ok , here is the drill
BTW: coolant , abuse, not changing it every 2 years, or not at all. Abuse. sorry.

1: make it all clean, no green, lol
2: make sure cap on rad seals, no cracked seal under lid.
3: cap ON, ( if not sure buy a cap)
4: start engine, let it warm up 100% then wait 10m more. after gage hits Normal.
5: the system quickly presssurizes after the warm up to 12.5 PSI,.
See , the system is all every inch under pressure.
now just look at ever hose , every fitting, pump , RAD,


hoses can Piss. ( and can go anywhere it wants to ....)

Answer , if clutch (bottom bell) inspection port is dry, then the back of motor is not leaking.

never skip the above trick , that costs not a dime to do a full presssure natural leak test.
it always works.
if not , drive a mile, come back and look again. (dont drive too far)
we want mininum signs ,not a hurrican of green junk all over everything.

the hose dont last 20 years, BTW.

10 yrs. is tops , design life. not life of motor.

[mike29]

I was losing coolant very slowly (and mysteriously) then one day the upper hose from the rear of the block to the heater core exploded. When I fixed that I lost no more coolant, so it probably had a pinhole leak before it ruptured.