Water pump replacement
Thread Starter
Advanced
Joined: Jun 2003
Posts: 73
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From: Houston TX
Water pump replacement
I'm not a Corvette owner.....yet. I turn 50 this year and about to get the kids off the payroll so hopefully I'll have one soon. What's the deal with C4 waterpumps and radiators? I see a lot of people have them replaced at less than 50k. Optispark as well. I've driven cars hundreds of thousands of miles and never replaced a radiator unless it was damaged.
Melting Slicks
Joined: May 2007
Posts: 2,171
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From: Warwick RI
I'm not a Corvette owner.....yet. I turn 50 this year and about to get the kids off the payroll so hopefully I'll have one soon. What's the deal with C4 waterpumps and radiators? I see a lot of people have them replaced at less than 50k. Optispark as well. I've driven cars hundreds of thousands of miles and never replaced a radiator unless it was damaged.
I can't speak from experience on the opti-spark but from what I read they don't much care for moisture, that is one of the issues.
I think that 50 is a good reason to get yourself a present so we will be seeing more of you soon I suspect
Safety Car
Joined: Jul 2008
Posts: 3,966
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From: Made In America
St. Jude Donor '10-'11
These cars run hot and people are always trying to "fix" that. You also have to remember that many of these cars are not daily drivers so even though the mileage may read under 50K they are 20+ years old in some cases. If things that are designed to spin don't spin they tend to get stuck that way
I can't speak from experience on the opti-spark but from what I read they don't much care for moisture, that is one of the issues.
I think that 50 is a good reason to get yourself a present so we will be seeing more of you soon I suspect
I can't speak from experience on the opti-spark but from what I read they don't much care for moisture, that is one of the issues.
I think that 50 is a good reason to get yourself a present so we will be seeing more of you soon I suspect
They run about ~235* without the fans on then the fan kicks in. If you are looking to get it cooler, a Dewitts radiator, BeKool waterpump, and a aftermarket fan switch will get you down in temperatures. Also, if you add a Big Mouth Air Dam, that will get more air to the radiator. When you add/change the coolant, always use Distilled water. Never tapwater because tap water will eat away at the rubber pieces throughout the cooling system. C4s are pretty cheap, especially now. If you get a L98, they are notorious for blown head gaskets. LT1s have the Optisparks which go out if they get wet.(usually). LT4 and the famous LT5 are big horsepower motors but they are more expensive and thats if you can find one. If you get a earlier style, 84-86, then you should upgrade to the later style window regulators as the early ones run on a ribbon and are quite slow. When you get it, flush out all the fluids and change them yourself. Spark plugs are kinda hard on the L98s to change. If you are looking for low end torque and fast exceleration, the L98 is the choice. If you want high end power, the LT1 is the way to go. Happy Corvette hunting to you.
Le Mans Master
Joined: Dec 2006
Posts: 5,154
Likes: 2
From: Ft Myers Florida
They run about ~235* without the fans on then the fan kicks in. If you are looking to get it cooler, a Dewitts radiator, BeKool waterpump, and a aftermarket fan switch will get you down in temperatures. Also, if you add a Big Mouth Air Dam, that will get more air to the radiator. When you add/change the coolant, always use Distilled water. Never tapwater because tap water will eat away at the rubber pieces throughout the cooling system. C4s are pretty cheap, especially now. If you get a L98, they are notorious for blown head gaskets. LT1s have the Optisparks which go out if they get wet.(usually). LT4 and the famous LT5 are big horsepower motors but they are more expensive and thats if you can find one. If you get a earlier style, 84-86, then you should upgrade to the later style window regulators as the early ones run on a ribbon and are quite slow. When you get it, flush out all the fluids and change them yourself. Spark plugs are kinda hard on the L98s to change. If you are looking for low end torque and fast exceleration, the L98 is the choice. If you want high end power, the LT1 is the way to go. Happy Corvette hunting to you.
Le Mans Master
Joined: Sep 2003
Posts: 5,874
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From: Littleton CO
Just confirm with the seller when/if these things were replaced, don't deliberately drench the opti, don't let a water pump leak coolant on it (especially!) and don't let it keep you awake at night.
Knock on wood.
Melting Slicks
Joined: Feb 2008
Posts: 2,384
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From: West Chester PA
St. Jude Donor '09 thru '25
[QUOTE=jrp;1569083886]To the OP: Don't let the Optispark chatter scare you away. I still think the troubles - and there are some - are overblown somewhat by internet amplification. How many threads are people going to start to say, "Hey guys, my opti still works!" vs. the ones which get piled on by everyone who has had one go bad?
Just confirm with the seller when/if these things were replaced, don't deliberately drench the opti, don't let a water pump leak coolant on it (especially!) and don't let it keep you awake at night.
BTW, my opti still works!
Just confirm with the seller when/if these things were replaced, don't deliberately drench the opti, don't let a water pump leak coolant on it (especially!) and don't let it keep you awake at night.
BTW, my opti still works!
Race Director
Joined: May 2006
Posts: 10,691
Likes: 71
From: Phoenix Arizona
The optispark is merely a distributer in a bad location. I've had lots of the LT1's over the years, and have had maybe one problem. (most of the cars I deal with are over 100k miles, some way over). The 94-96 cars are by far the best C4's performance, comfort, reliability, and quality wise. Most of the C4 cooling problems were solved when they changed radiator assemblies in 1990, and then when they went with the reverse cooling in the LT1's. Prices are about as cheap as they've ever been for a Corvette, it's definately time to buy! By the nature of a forum, all you ever hear about are the problems. Count up all the problems you've heard about C4 corvettes, and then remember they made 330,000+ of them, most still on the road!
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Joined: Jun 2003
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From: Houston TX
Thanksfor the info. I hope to be in the market seriously this summer. I am constantly looking at Corvette Forum, and other sites, for C4s for sale. I'm driving my wife crazy. I think I wore her down and she agreed to let me buy one when I turn 50. Wishing for a low milage 94-96 6 speed vert.
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Burning Brakes
Joined: Dec 2007
Posts: 805
Likes: 3
From: Waco TX
Like other's have said, don't let the optispark scare you. It's about the only bad thing about these cars. A previous poster put it well...there's nothing wrong with the opti other than it's location. I haven't had any problems with my 94.
I would say the waterpump is about like any other car (on LT1's). Although, with regular use, logic would make you think it would last longer since it isn't belt driven and doen't have that sideload on the bearing like traditional waterpumps. But if a car sits for a long time...
As far as the temps running hot, that is only really true in heavy traffic or while idling for a long time. As long as the car is moving, mine rarely gets over 200. If you do get an LT1 and it runs hot, flushing the coolant system might help. I noticed my temps dropped significantly after I had mine done.
I have never heard of radiators failing any more or less than a normal car. If this is a common problem on LT1's, it's news to me.
I would say the waterpump is about like any other car (on LT1's). Although, with regular use, logic would make you think it would last longer since it isn't belt driven and doen't have that sideload on the bearing like traditional waterpumps. But if a car sits for a long time...
As far as the temps running hot, that is only really true in heavy traffic or while idling for a long time. As long as the car is moving, mine rarely gets over 200. If you do get an LT1 and it runs hot, flushing the coolant system might help. I noticed my temps dropped significantly after I had mine done.
I have never heard of radiators failing any more or less than a normal car. If this is a common problem on LT1's, it's news to me.
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
I replaced my water pump at 112k miles on my 96 vette.
Noob to fixing things so i basically dumped about 1gal of coolant on the opti and it still worked fine afterwords.
the water pump started leaking which is why i replaced it.
Noob to fixing things so i basically dumped about 1gal of coolant on the opti and it still worked fine afterwords.
the water pump started leaking which is why i replaced it.
Safety Car
Joined: Sep 2002
Posts: 4,971
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From: The reason time exists is so everything doesn't happen at once
Thanksfor the info. I hope to be in the market seriously this summer. I am constantly looking at Corvette Forum, and other sites, for C4s for sale. I'm driving my wife crazy. I think I wore her down and she agreed to let me buy one when I turn 50. Wishing for a low milage 94-96 6 speed vert.
I drove my wife crazy as well. Just before I turned 50 I kept talking about getting a Corvette; she didn't want to hear about it. She finally gave in when I came home with a Harley catalog.
Seriously, these cars are very reliable if properly maintained. The LTx engines are designed to run hot, and they do. I think if GM had not put a digital temp readout in the Corvette about 90% of the "my car runs hot" posts would never exist. In addition to changing the fluids make sure you replace the coolant with the same type that is in the car (green for green or orange for orange) don't mix them or you'll wind up with a cooling system full of jello. Also make sure the space between the radiator and the ac condensor is clean. These cars suck up all kinds of road debris.