tommyeflight89

iTrader: (4)

Hey guys,

I noticed yesterday that my coolant reservoir was at the low mark with a cold engine. It seems to have gone down by two inches over about 2k km.

Other than that car is behaving. No symptoms of coolant seal failure.....zero smoke hot or cold, no smell. No hard starting.

The car has 103k km. Water pump and coolant were flushed recently. Coolant looks clean. Rad cap seems good. Car stays at operating temp fine, doesnt heat up.

When doing my homework, I read it also may be at the intake manifold, which wouldnt surprise me as its from a 74 rx4 so isnt stock. I can't notice any external leaks!

Any advice from the experts? Is this a very early symptom of coolant seal failure?


I hope my motor is ok, she is running so good. (:

Siraniko

iTrader: (13)

If u have a rx4 intake, then u have a 13-B. Fill up the radiator and the reservoir, if it low again, replace the radiator cap.

tommyeflight89

iTrader: (4)

It is original 12A with a older intake mani/carb setup. It has an old Nikki on it that isn't from an Rx7.

So I poked around under the hood today after driving it with the engine idling. I can see evidence of coolant leaking from somewhere. There were several drops on the engine underpan and some even at the bottom of the fan shroud. So something is definatley up,I am thinking it is a small leak somewhere, not coolant seals.

How would coolant find its way onto the inner perimeter of the shroud?

diabolical1

iTrader: (3)

you're just going to have to clean everything and set out to catch it in the act.

have you checked the radiator itself? i once had a leak that turned out to be a rotted section of the radiator obscured from clear view. when i found it, pieces flaked off in my hand and literally disintegrated in my fingers.

also, if you definitely have a 12A, then the chances of you actually having an Rx-4 intake is slim to none. was this change info you got from a previous owner or was it a change you made to the engine? either way, i suspect faulty info somewhere along the pipeline.

tommyeflight89

iTrader: (4)

Update... Perhaps the signs of coolant I saw were just left over from me messing around with the rad cap and expansion tank. I looked hard, no signs of external leak.. just my wishful thinking.

But, after doing a lot of research on the forums, I am beginning to think its an issue with my rad cap. My main plunger gasket is flattened and very deformed, curling over the perimeter of the metal plunger. Perhaps this entire time I simply had issues with the cap, not letting coolant flow from the expansion tank back into the rad once it cooled down.

I do recall that when I first was driving the car, especially when starting on a hill, the "Coolant Low" light would come on for a short period of time. This means that the rad was not filled completely even though there was coolant in the expansion tank.

I am almost certain that after doing quite a bit of driving, especially in hotter weather, and messing with the cap (I took it off and put it on a few times), all I did was fix the system, and now the rad stays full, which explains the coolant "loss".

Every time I check the system now, coolant is right at the brim of the rad. I have trimmed the flattened gasket flush with the perimeter of the metal plunger.

My Plan: Do a "Champagne Test" to ensure it is not a coolant seal issue. I have already pulled the leading plugs and they look great.

Hopefully this thread serves as a good reference for anyone with a coolant seal scare.

I think Siranko nailed it with the rad cap.