20 replies to this topic

[makus0025]

This past weekend I ran both days at milwaukee mile and kept on losing the water in the radiator 3 of the runs it just disappeared I had no idea where it went but 1 run it sprayed brown water all over the left side of the engine. It seemed to spray that time from the radiator cap. I have no idea why the water was brown I have always used distilled water and water wetter.

I also noticed when the engine was cool the radiator hose was soft but once the engine got up to temp it was very firm.

- about 15 laps in I could smell like the engine was running hot but the stock temp gauge looked fine.

- the oil level and color looked fine.

- the electric fan does come on after the car comes up to temp


After getting home I can tell it wasn't leaking from the radiator cap
the water level is down in the radiator and the water inside is brown again.

[makus0025]

pic1  111.jpg   44.61KB   76 downloads

[Alberto]

Time for a coolant system pressure test

[Ron Alan]

FYI...I'm not an expert!

Our motor got warm recently and the cap popped...which sends water into your overflow tank and then out the overflow hose. Ours showed up on the hood coming out around the head light(NA). For us this was strange as our car never over heats...turns out it was a weak/tired cap. No problem after we replaced it. Your hoses should be hard when the car is warm...you want pressure which allows the water a higher boiling point. And when the car is cool the hoses will be soft...no pressure!

Brown is pretty typical as the iron block does rust. But just how much is normal I don't know...steel radiators(parts of) I've also seen rust. I'll leave this to one of the real mechanics here to advise you.

[dstevens]

The water color is normal for higher mileage cars or street engines converted for race use and have not been hot tanked. Sounds like your cap fails under pressure.

Looking at the pic again, the way to test is like Alberto says. Pressure test will tell where your leak might be.

[Johnny D]

It may be only the cap.
Then again it may not.
J~

[Charlie Hayes]

In that picture it seems like there is a big spot around the heater hoses? Could be a pinhole crack in those hoses? The cooling system is pretty simple on these cars there aren't to many options for possible problems.

[Bench Racer]

If you live in the Milweaukee metro area provide an e-mail or phone number & we can take a look.

[joeg5982]

I vote cap.

[dmathias]

Someone told me this at my last race - Radiator caps are cheap enough, buy two. Then you have a spare.

[Glenn]

My vote is heater hose with the staining that far back

[makus0025]

Thank you everyone for the help

So far I came up with it is not the cap, for 1 I just put a new one on and 2nd the air intake tube is clean no brown on it so the leak must be from behind the intake tube . Everything is coated starting by the thermostat and back.

[dmathias]

How old is Walter Pumpe?

[Dave Cox]

I would say check the neck where the hose connects to the head make sure that gasket hasn't failed. I have had to reseal that area in the past. Hard to tell, but it looks like the cam gear cover (in the front) might have some orange on it.

[pat slattery]

Pressure check the radiator, most places like Auto Zone, etc. will have a loaner you can use. You should find out pretty quickly.

Pat

[wreckerboy]

Time for a coolant system pressure test

This. Stop guessing and find out what is really wrong.

I had a cooling system leak at the track a few years ago that I could not pin down and eventually had to pack it in for the weekend. When I got home I invested about $125 in a Stant pressure testing system and found the problem in about 30 seconds - a pinhole leak in a heater core hose that only appeared under pressure when hot. The bleeping thing was spraying like a fountain.

$125 may seem expensive at first blush, but compared to the possible costs of a blown motor while you are shotgunning parts at it, and/or the costs of lost track days, it starts looking real cheap. I've used it several times since and it's worth it's weight in gold to me. It has also become one of those "I'll take it with me to the track to assure that I'll never need it again" tools.

[Dave Metz]

Thank you everyone for the help

So far I came up with it is not the cap, for 1 I just put a new one on and 2nd the air intake tube is clean no brown on it so the leak must be from behind the intake tube . Everything is coated starting by the thermostat and back.

Check the pipe under the exhaust manifold that goes to the heater hose. I just found a leak in mine at the bend and that looks like the general area that most of your brown is. Just a thought. I found mine with a puddle under the car tonight (rusty as well) - filled the rad back up and it started dripping again. Traced it to the underside of that pipe.

[fishguyaz]

Thank you everyone for the help

So far I came up with it is not the cap, for 1 I just put a new one on

a well known formula car mechanic i know says

" if it just came out of a box is is assumed not to work, unless it proves itself otherwise."


also +1 for the coolant system pressure test.

[Jerry Cabe]

a well known formula car mechanic i know says

" if it just came out of a box is is assumed not to work, unless it proves itself otherwise."


also +1 for the coolant system pressure test.

So the new Coolant System Pressure Tester is assumed not to work correctly?

[Dennis]

I have the Radiator Pressure Tester from Harbor Freight for 79.99. It's got adapters to fit almost any radiator so useful for all my other cars as well as SM. The Miata started losing coolant during qualifying for the 25 Hour. With the tester we found a pinhole leak in the oil cooler coolant hose in the back of the head in a few minutes. Saved our @$$!

Now I do a pressure test every time I do any work on the cooling system, just to be sure. Money well spent.

Dennis