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Water pump/ Opti?

2080 Views 13 Replies 6 Participants Last post by  Michael Knight
So I noticed the water pump leaking from the weep hole. Time to replace obviously, but is there any way to check the opti for any damage? It looks fine and the car was running fine. Don't want to replace if not necessary.

Also, any suggested brand for water pump?
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You can start it without the water pump on to make sure the opti is still working fine. Just do not fun it very long. As for the water pump, I prefer a gm one but the ones from autozone, ect will work fine. How many miles on the motor?
Only 75k.
The opti was replaced once about 10k ago.
Ok,if it had alot of miles i would say replace the opti while you had it apart. Just do the above and put the pump on. Bleed the system when you are filling it and go have fun with it.
My suggestion is to not drive the car with a leaky waterpump. Moisture/antifreeze will really damage the internals of the opti. Until the pump is fixed I would put a cloth or plastic over the opti to prevent moisture getting in! ed
Just some recommendations:
1). Tap weep hole at bottom of pump and insert a zerk (grease) fitting with a rubber hose routed away from the OPTI. The zerk fitting will have to be taken apart. I use a 45*
2). At this time install 160* thermostat (if you think you need or want it)
3). Also when filling the system loosen the bleed srews to allow air to escape while filling. This is actaully the correct way.
4). You could also RTV the opti and before the RTV dries place a flexible strip of plastic on top side the width of the opti and use a large rubber band to hold it in place. Also you will need to heat the plastic to form it to the opti shape prior to this. Or just use RTV
you have to pull your waterpump. the opti will be right there.

take it off and open it, and inspect the low voltage side. if there are any signs of water intrusion damage, they will be pretty obvious, all over the optical sensor and timing wheel.
^^^, just remove the cap of the opti and inspect. it will be evident if coolant got inside. recommended to remove rotor anyway and use blue locktite on rotor screws

I would not put a 16o stat in unless you are tuning for performance requireing lower engine temps...just throwing in a 160 is not advised

WP...I went electric in 99 and never looked back. mechanical pumps..I would get a "new" one from NAPA and avoid reman. AC Delco will also be OK

the mod of putting in a 90 degree fitting in the weep hole to re-direct leaks away from opti has been done and assume it does keep the Opti protected but the wp is still failing. typically the belt throws the coolant all over, including opti, so seeing evidance of leaking on floor is not until it really leaks bad.
run the coolant redirect line down to the ground to keep it off your belt too

i never bother with that shit though, i get brush-on liquid neoprene (otherwise known as liquid electrical tape) and basically just coat the entire opti in it. screws, everything.

i pack the connector with dielectric grease, then i paint the hell out it with neoprene too.

the main problem with the stock opti venting mechanism is creating vacuum in an imperfectly sealed unit, so in the process of evacuating moisture, it sucks more in. if you coat the sucker real good, there's less places for it to draw moisture from.
Thanks for all the great advice.

So no 160 without a tune?

I stopped driving as soon as I noticed the antifreeze. It was only about two quarter sized drops on the floor. It doesn't appear that too much leaked. Haven't driven it since. I'll check it just to be on the safe side. Definitely will add a safer way for the new pump to drain.
You are getting good info from all the guys. I am with BALLSS regarding using an electric water pump,I have had my Miziere on for about 3 years and its really worked out well. My opinion, the electric pump really simplifies the engine compartment. ed
you can absolutely install a 160 degree thermostat without a tune!

you will get 100% of the advantages of it when you're in motion and your air dam is working instead of the fans

you will get between 100% and 0% of the power gain in launching after hot idling at a stop light, as your fans will still be tuned for the hotter thermostat. how much power you'll gain will depend on how long you've been idling
Well the Opti looked good, and the new waterpump is in. Really wasn't that bad of a procedure. I wonder how much a shop charges for that? Even dropped in the 160 stat. Definitely runs cooler.:thumbsup:

After putting it all back together I have one question. Does anyone know what the harness plug on the left side of the intake tube between the filter and throttle body is for? Mine is very loose.
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