Water pump already?

[MARKSC4]

Water pump is seeping just a little and the belt is throwing a line of coolant up under the hood. I didn't think at 31K miles I would be in for this, but maybe it is because the car sits for long thru the winters here??

It seems to stop after the engine warms up. But, I guess I'll do the safe thing and replace it before it takes out the optispark.

I have searched the forum and it seems that anytime the water pump is mentioned, it's just in passing to talk about changing the opti.

Is it that simple of a project that it doesn't seem to warrant any threads of its own?

Can anyone share any insights, tips tricks, or advice?

I appreciate any and all input, and value your suggestions.

Thanks in advance. Mark

 

[jmccloud]

Water pump

There are some threads from about 3 years ago. I don't know if they show up on the 'search' tab above but it's worth a try.
One of the bolts is a booger, I think it's the lower one on the driver's side. Use a deep wall socket rather than a normal socket and extender (they're too long). Other than that, be sure and get all of the coolant out before removing the water pump; the best way is to raise the car and pull the knock sensors. They're about 1/2 way back on the block and just above the pan. There is a shield over each that comes off easily. Pinch the electrical connector to remove it from the knock sensor (pinch the long dimension) and use a pair of pliers to do the pinch if your fingers aren't strong enough. Don't pull the connector off with a lot of force, once pinched it will come off very easily. The knock sensors have a hex fitting but someone had boogered one of mine so I replaced it. Had to remove it with a huge set of channel locks. Get out of the way when unscrewing the knock sensors, there's going to be a flood.
When you refill, open the bleed valve (older C4's had 2 bleed valves but my '95 has only one at the thermostat housing) and put a rag under it to catch any drip. Filling takes a lot of time so the air can escape. The manual recommends 'avoiding any agressive maneuvers' until the engine temperature has cycled fully at least three time. If the temp gets to 260, shut it off (that's where 50/50 water/antifreeze boils). My experience agrees with the maual and the temp. hasn't gone over about 240 albeit at strange times (cruising). After 3 days (temp cycles) everything was back to normal.
The service manual also recommends adding "Cooling System Seal Tabs" GM part 1#3634621 to the refill fluid. I've found that it's much easier to dissolve them into the coolant before adding it to the car as they aren't very soluble (shake a lot to help). I used to work at an assembly plant and every car got this treatment but the public isn't aware of it.
Hope this helps.
PS Get a Helms manual. The others will mislead you.

 

[JOE BYRNE]

Off the subject

Mark,

Just wondering if you have always been in the Canton area. Bought my 73 From Northwest off Whipple a couple of years ago. Traced down a mechanic down there that did some work on it (from a sticker) back in the 90's but doesn't recall the car from description. Just wondering if you had ever seen this one over the years. If you get a minute shoot me an email at byrnejoe@sbcglobal.net

 

[c4cruiser]

FWIW, GM no longer recommends the use of the sealing tabs. There was a service bulletin issued to dealerships a couple of years ago that said there was a possibility of the cooling tubes in the radiator getting clogged up if you used all six of the tabs so GM decided to drop them from cooling system service procedures

The late model water pumps are not too bad to replace; just take your time and be sure to get all of the accessories out of the way. You should get a new serp belt too (even with only 31K on the car, the belt is still 11 years old!).

The later OptiSparks are sealed better and they have a vacuum line that sucks moisture out of the cap and back into the motor.

Your car uses DexCool so make sure that is what goes back in. While it's not a requirement to use distilled water as part of the fill, it's well worth doing. You can get distilled water at most grocery stores for around a buck a gallon. If you drain all of the coolant from the system (by pulling the knock sensors) you will need two gallons of DexCool and two gallons of distilled water.

 

[6speeder]

FWIW.... with coolant flying around the engine bay it is likely that some moisture may have entered the opti. You may not know for days or months if corrosion is silently at work. Just in case that you are not aware that once you have removed the water pump, the opti is exposed, and replacement is not that difficult. It would be a shame to go through the labor to remove the water pump, and then have the opti fail a month or two later, and have to experience the same process all over again.

With 31K on the odometer, the opti could fail at any time, or last until 100K. There is just no way to predict the life of an opti. With moisture in the engine bay, the odds are in favor of opti failure sooner than later.

As C4cruiser suggested, replace the belt (belt life averages 35K to 40K).

 

[MARKSC4]

Excellent info ! - I sure am glad to have a place to get this kind of detailed help!

Did you guys also replace the o-ring on the spline behind the coupler?

Should I buy the GM performance water pump? Are the gaskets separate? It is not clear from Summit Racing's web site whether they are included.

How long does this project generally take?

Thanks again

 

[6speeder]

Should I buy the GM performance water pump?

Check ebay (partsladi-gm-delco-parts-direct) for OEM AC Delco replacement - about $150 for the pump, and $290 for the opti (Dynotech $600) - your choice.

How long does this project generally take?

Save both days of a weekend.

 

[94C4]

My water pump went bad at 48,000 on my 94. It was about $800 to replace it at the Chevy dealer. That included a new belt.