Hi all, Last weekend I purchased a 93 Z28 with 150k miles for $2000. I knew BEFORE hand that the car had problems overheating and was getting water in the oil. I am pretty mechanically inclined, so I decided to make the purchase and pull the heads and take a look. I am pretty familar with earlier model 350s, but this LT1 is different in many ways. Here are my questions:

1) Could the water pump be a potential source for the problem. This is the first water pump that i have had that was gear driven off the cam. If it were to fail internally, could water find its way into the oil?

2) Are there any good additives that can help get rid of the residual water in the block once i get it put back together? Im planning on changing it a couple times after a couple hundred miles each time, but would like to use a product to help. Im going to clean as many parts by hand that I can while i have it apart, but know i cant get it all by myself.

3) Do these cars have a reputation for blowing head gaskets or cracking or warping heads? I dont mind if the problem comes from the heads or head gaskets. Im concerned about the block....I REALLY DO NOT want to pull the motor. What is the likelyhood that the block is damaged?

4) Finally, if i replace/upgrade the top half of the motor, do i need to worry about blowing out the bottom end? I would like to get the most out of the motor while i have it torn this much apart? Cold air intake, port/polished heads and intake, upgraded ignition and injectors, headers, and custom PCM are the mods im considering. Is this too much for the lower half considering it has 150k miles?

Thanks for all the advise!!

 

i don't understand how the water would find its way into the oil, unless they are connected in some way, in which I don't think they are. But there could always be other problems with the oil, for instance what your dealing with..?

 

And yea, the problems with your water, are you refering to the pump for the engine coolant? cus if so you should get that fixed quickly because if it is not pumping what it needs to (antifreeze), that is how your engine block could crack. Wel this is if that is what your refereing to. Another thing, your talking about adding all of these things to the top/bottom half of your engine, well it would be in your best interest to call the guy you bought the car from, and ask him alll of the problems he had with the car, and what he got changed and fixed. Once you know all that, you konw where there may be some weak spots in which you can watch out for or even prevent from braking again. Basically, the car has 150K miles on it which is a good amount, so you should do what I did and bring it to a mechanic and get an estimate of how many miles your engine will last up to. See with mine, i have 74K miles on it and the guy said it would last between 180-200K miles, which is fine for me. So just call the guy, see what's up and try and get a mechanic to check your engine for an estimate on the miles.

 

If you have water in the oil, there are several possible causes. A cracked block or head, a blown head gasket which will also cause overheating, the factory oil cooler may have sprung a leak (if your car is equipped with one), or it could just be condensation if the car has been sitting doind nothing for a long time. The Camaro LT1 has aluminum heads, and like all aluminium heads they are prone to warping if the engine overheats. The water pump is built so that it won't leak into the engine, but it will leak on top of the optispark distributor and kill it. The bearings and rings were probably damaged by the oil & coolant mix, and considerng the mileage on the engine a full overhaul is a good idea.

 

z28pete thank you for helping me out, mostly because I stated I wasn't completley sure of the situation. But now that I read what you stated I undsrstand. So "spm" that is what you need to worroy about.