Use the bleed screw on top of T stat housing. Run engine until T stat opens, then open bleed screw until coolant flows steady (read not in spurts). Use a rag around it to keep coolant from puking on opti

Installing the bleeder mod that allows you to just run a clear tube into reservoir is the mess free way of doing it. I bought mine over 20 years ago so IDK where to get them now

 

I been doing that but still seems to rise up too close to red, and then I'll come down.Primary fan kicks in but it get to close to red before it kicks in

 

Is this correct hose, I need a plug, or is it the other one?That's plugged into the reserve

 

Is that a garden hose?

 

unplug he sensor on front of WP and start engine. Both fans should start running so you can confirm both do in fact work

 

They both run as soon as I unplug the censor

 

your fans work properly

no, none of those 2 hoses are involved in using a bleeder. I was referring to an aftermarket product that from my understanding is no longer available. It does make bleeding the system simple and mess free though

Sometime bleeding all the air out of the system is difficult but must be done. You can try raising the front of car on ramps or parking on a slight incline which may allow air to get forward easier.

 

I understand I see the bleeding nipple
And that's where i'm bleeding it from but still gets overheated

 

You may need to burp the air out and top off the cooling system several times over the course of a week or two for best results.

If you still find that the fans come on too late for you, even after you've done everything else,
then your 'problem' is with GM's OE fan-on threshold temps.
If you want the fans to turn on sooner than 225F & 232F, you can either use the AC (assuming it works properly),
or you can have your pcm tuned for more reasonable fan-on temp thresholds (among many other desirable improvements).

 

But before it was not getting over heated. I changed the optispark and then it started to get over heated. Like I said water pump only afew months old and it's not that cheap aftermarket ones

 

Drain the cooling system and then unbolt the front of the water pump. Make sure the impeller is tight on the shaft and does not spin by hand.

Have a friend start the car for a few seconds. You watch that impeller and make sure it spins with the engine. Reinstall the water pump cover with RTV in addition to the o ring.

 

IMHO, a slipping impeller can happen, but I have never encountered that problem. Another cool feature of the EWP is the rubber cap you pop off to confirm impeller rotation

Both OP's fans work and new WP installed so the most "likely" culprit is there is still air in the system if high temp "spikes" are observed

This type of bleeder makes it easier, and mess free, to bleed using a clear hose run into reservoir so you can see when bubbles stop. Its different from the one I got over 20 years ago but des the same thing

coolant bleeder valve (yourcustomcar.com)

With that said and what sherlock suggests is any replacement part recently put on, in this case water pump, can be defective

Another cause is the spline coupler that drives the water pump from engine...I assume OP put his back on but if teeth in it are worn...it will slip. It is highly recommended new ) rings are used on the WP drive spline on a WP swap and a skim coat of grease applied to both WP and WP drive splines

 

It is amazing how much work people will do before checking the live data temperature or measuring the resistance of the waterpump temperature sender at the PCM connector.
If the PCM has bad data it will not run the fans, or will run them all the time.

But before it was not getting over heated. I changed the optispark and then it started to get over heated.

unplug he sensor on front of WP and start engine. Both fans should start running so you can confirm both do in fact work

They both run as soon as I unplug the censor

If you unplug the sensor, go for a drive at under 50MPH and the car runs normal or cool temperatures I would suggest a sensor problem.
If it overheats with both fans running I would check the waterpump as sherlock suggests.

 

Try the above that Z09B4U says. Also, I am confused about the water pump you put on. Not aftermarket? Almost all "official" Delco parts are Chinese junk now. The aftermarket for the Opti is a total joke unless you do Petris. Just better to clean it up inside and replace cap and rotor with Standard Products DR-473T. Finding a NOS water pump is hard these days. It could very well be a crap WP out of the box, or you installed something wrong. Annoying, I know, but you have to be very slow and cautious when doing a Opti and WP. Easy to overlook something. Just did both on my Roadmaster. Took my time, which some people don't have, and it worked out well with help from here and Factory manuals.

 

Yes it's delco what everyone recommends to get other then the non name parts were can I find petris optispark

 

Petris Enterprises

 

Do you guys think my water pump went bad ? I bought it march 14 and its over heating

 

Who knows, do the suggestions you were given and take it from there.

 

I give up I replaced water pump and stills over heats 🥵 🔥 I'm guessing I'll need to go with electric water pump 🤔

 

Don’t. Getting an electric water pump was the worst decision I have ever made.

 

You replaced WP twice now??

if so its either a bleed issue, wrong T stat (needs to be LT1 specific), fans not working or your radiator is F'ed

 

Wrong t ? Fans are working i notice the the driveshaft that connects to the water pump was not spinning andand it over heats then it spinning and it don't over heat

 

Sounds like it is slipping somewhat, and that's never good.

 

That's what I'm thinking so I ordered a new coupling hopefully it's fixes my headache

 

There's supposed to be at least one (if not two) O-rings involved between the enigine's cam nipple, the spline key sleeve, and the H2Opump.

 

the O rings mentioned go on both the WP drive spline and WP spline to "stabilize" the coupler from vibrating...typical cause of WP drive seal leak

There have been posts of people having worn/stripped splines in the coupler which can cause what OP is describing. If the splines on the WP drive gear are also worn/stripped...the shorter path would be go EWP as replacing that gear and drive is a big job. The gear can just be left in the motor with EWP

 

That's what I'm thinking I'm just going to trying with a new coupler I ordered ti see if it fixes the issue if not I'm going with ewp any recommendations of videos or step by step instructions on how to do it ?

 

I found this helpfull. I can't remember, and I'm not able to re watch this at the moment, but I seem to think they used a hammer to push out a peice. I definatly needed a press. Hammer was not getting the job done.

 

Did you remove the shaft coming from the block ?

 

Any one have a old not working wp I don't want to destroy my new water pump

 

I may have punched the impeller off with a hammer and punch, and then needed the press for the bearing. I think the seal was with a screw driver.

Sorry, can't remember 100%.

 

Well i got the new coupler so I will install it today wish me luck hopefully it works and stays working correctly

 

Ideally the new coupler will work. Look inside the old one to see if splines are worn down and inspect the make splines on WP drive gear itself. New WP splines "should" be perfect.

Regarding EWP, I just used a 5lb hand sledge to pound out shaft and bearing from rear of pump. No big deal. A press would easily do it if you have one. The EWP comes with a freeze plug to fill that hole. The EWP has instructions IIRC but no step by step on any wiring. I just bought a generic Painless Wiring relay/fuse and used a trigger wire for the signal side of relay and the AUX post for the +12v. Its been over 20 years since I did it so can't recall which wire I used (pink??) from the under hood fuse block. Relay and fuse are mounted on firewall behind fuse block

Once you get the guts out, you will see if AC Delco spent $.05 instead of $.02 on the bearing/seal....the common pump leak would not be as frequent

 

Replaced the coupler and still over heats so ewp it will be 😞

 

Methinks you are heading down the wrong road.

If the water pump is turning ( you haven't illustrated to me you have proven it stops turning )
putting an electric pump on is not going to solve your problem.

I keep wondering about blocked head bleeds although it is not a popular theroy here.

 

Explain please block heads bleeds ?

 

...so it started overheating "immediately" after Opti and WP swap....or 3 months later??

 

Is this hose important its capped off at the other end