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Discussion Starter #1 (Edited)
If a mechanical pump fails or begins to fail, the Weep Hole on the bottom of the pump will start to leak. This is an early warning that the pump needs to be replaced soon. Unfortunately, GM Engineers placed the Optispark Distributer directly below the Water Pump. If the WP leaks, it’s possible coolant could damage the Optispark. There are 2 possible solutions to this problem…Convert to an Electric Water Pump OR somehow protect the Opti by diverting anything that may leak out of the Weep Hole away from it.

The easier least expensive option was to install a Fitting in the Weep Hole and attach a drain hose to route a leaking WP away from the Opti. I did this mod with the WP off the car, but if you remove the Balancer you “may” have enough room to do this same mod from under the car with the WP still mounted to the engine. Anything you can do to help protect the Opti in the event of a WP failure is well worth the effort. I’ve also seen a metal shield that mounts under the WP to protect the Opti during a WP failure, but a drain hose seems like an easier option for me. I found that a ¼” 28 Thread Tap was perfect for cutting threads into the Weep Hole.

I wanted a fitting with this thread size/count and a hose barb on the other end but only found these online. I went to a bunch of stores (Fastenal, Home depot, Lowes, Tractor Supply, Fish Supply Store, etc.) with no luck. Instead, I just used a 45* Grease fitting and drilled the end to remove the metal Ball and Spring to open up the fitting. You may also be able to use a 1/8” NPT fitting and tap for this thread but I cant confirm that size fits as none of the stores I tried had this size in stock either. Most carried a ¼” NPT thread fitting but it is about twice the size of the Weep Hole and this would require additional drilling of the WP housing which I would not recommend.

I cleaned, primed and painted the pump with High Temp paint, then used a ¼” 28 Thread Tap to put a few threads in the bottom for the fitting. I used some grease in the Flutes of the Tap and also held it upright to keep any metal shavings from staying in the pump. But the shavings are very minimal.

Here is the fitting installed and there is enough material on the fitting end that a thick walled Vacuum Hose along with a Clamp should hold the hose.









Notice the raised edge of the pump housing, I only mention this because a 90* fitting would only allow me to turn it in once before hitting this edge. This is something to keep in mind if you are considering which fittings to use and purchase. I feel the 45* angle also allows the hose to extend at a better angle than a 90* would. Even though the hose was clamped on really well, I wanted to make sure to secure the hose a little better. I just used some flat Stainless to fabricate a Metal Cable Clamp that the WP bolt would go through. The Cable Clamps we had at the Shop would not allow the WP Bolt to go through it so I had to get Creative. :)

Here are some pics of that piece and how the hose routes away from the WP Housing.





Once I finish up the install, I will route the hose down below the frame. I have enough length in the hose that I have a few options before I secure the end. I also ran it out the Driver side since there is already a drain hose coming off the Bleeder Valve on the Passenger Side. It’s a pretty tight area with the Accessory Bracket and I like the way the hose routed on the Driver side over the Spark Wires. Here are just a few more pics of the final install and you can barely notice the drain hose is there and it should do its job well. When you cut the hose where it exits the car, be sure to cut the hose at an angle rather than a straight cut. This will help keep the hose end from getting a blockage. Hope this helps save someone’s Opti from Coolant damage.



 

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Discussion Starter #4
Great idea and write up.
Thanks guys, hopefully this will help someone else out wanting to do this. I can't take credit for the idea as I've seen other info out there on other sites that also have a similar LT1 engine setup. I've seen all kinds of fittings used even some Plastic ones.

I just could not believe how difficult it was to walk in and get a fitting from a local store that I wanted to use. I could not see spending more money on shipping than the cost of the part and I needed it right away. The guy at the Fastenal Store just gave me the Grease Fitting since it was easier for him than writing it up and he was also a Former Camaro owner. He knew EXACTLY what I was talking about regarding the Opti and enjoyed the car talk. :) Said he missed his Camaro and just asked that I stop back in when I need some Hardware.

I found the exit location of the drain hose. I was going to just drop it down between the Power Steering Hose and the front of the frame. but was concerned it would pick up road debris and if it drained would blow back onto the car or suspension. Instead, I just ran it down the oil pan and tie wrapped it to the Oil Cooler line and then dropped it down behind the frame and slipped it between the Metal Brake Line and frame and angle cut it just level with the bottom of the frame. Anything that driops out while driving should just fall to the ground.
 

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Discussion Starter #7
pics lost to Photobucket...

Here are some pics I took when doing this mod...
 

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Discussion Starter #8
pics

more pics....
 

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