hi everyone, My 96 X300 is mysteriously looking coolant. When I top it off its fine for the first few days, then after about a week or 2 it starts to get lower and lower. I have had my hoses done because of a coolant leak, but now I do not see any leaks, and no spots on the driveway, and the resevior it still going low. If anyone has any ideas, please get back to me. Thanks.

 

Start by looking at the dipstick and see if the level is high and the oil is white. This is rare and would be from the coolant going into the oil pan.

If you have anti-freeze in the cooling system, smell the exhaust to see if it smells like coolant. This would be from coolant getting into one or more cylinders. Also smell for the coolant smell in side the car. This will be from the heater core leaking.

Fill the coolant system and have the engine running at about 1500 RPM and watch for bubbles showing up in the system. This could be a head gasket or cracked head.

See if you can rent a radiator pressure tester from the auto parts store. Pump it up to about 15 PSI and see if it holds. Look for leaks showing up.

Run a compression test. As you pull the spark plugs look and see if you have plugs that are cleaner than the others. Water going into the cylinders will clean out deposits. 160 PSI is good for regular gas and going up to 180 PSI needs premium gas. If you have a cylinder that is lower than the rest, or two side by side that are lower, then a head gasket could be blown out there.

 

After a long run do you see any tiney wisps of vapor when you lift the hood?

Small leaks can be hard to find...sometimes they never reach the ground. You can usually smell 'em, though. It took me ages to find a small drip where the thermo housing attaches to the cylinder head. Was a big leak but I had to top off every few days.

Since you had new hoses go 'round and re-tighten all the hose clamps. Sometimes they loosen after a few weaks.

Cheers
DD

 

I had this problem on BMW E30 it turned out to be a fine crack in the cylinder head....

 

The leak around water rail is hard to find. You will have to lift up your car and check precisely. In my friend's car's case, the coolant dried out around the water rail like stalactite in the cave!

 

At the bottome of the water pump there is a small hole from which coolant can weep. I have a similar problem on my 97VDP. I've gone over it thoroughly and had it checked by a trusted wrench. It's a gentle weep that looses about a teaspoon every few hundred miles or so. I'm told it is fairly common.

 

hey everyone! just figured out the problem, took it to my mechanic today, and there is a hole on my heater hose! It looks like its the 3 way hose that runs from the driver side firewall by the engine all the way around by the air intake area. Does anyone know where I can get it for a good price? Its over 100 bucks everywhere! thanks.

 

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NALLEY
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