Mistakes made while replacing water pump (still leaking around it)...

[Astro14]

Wire brushing aluminum damaged it. You cleaned off old gasket, and a bit of the surface, too, leaving a rough, not flat surface to which you attached the pump.

Having coolant on the surface prevented the sealer from adhering to the damaged aluminum.

Can’t do much about the first bit, except to remember the lesson.

You need a dry surface, and a good, gap filling, sealer when you do this again. Many recommendations have been made. Good luck.

 

[PontiacHO]

Before you disassemble make sure the intake isn’t leaking and running down the front. Some 3.8 Buick’s develop intake leaks. Just a though...

 

[HonorAndHonesty]

There are plastic elbows near the water pump. If they are original and you bumped them it could cause a marginal one to start leaking.
They make aluminum replacements. Your leak is likely an issue with the installation of the new water pump others have mentioned

Can you elaborate on bumping a plastic elbow?

 

[willbur]

It could be any of the above things or you could have damaged the gasket during installation or not got the new pump torqued down evenly. I've changed a few water pumps over the years, have never used sealant or had leaks afterward. I don't like using sealant on anything unless it's absolutely necessary because it's just more to clean up if you ever have to do it again. At this point all you can do is take it back apart and see if you can find the problem. I'd also put another new gasket on to eliminate the possibility of a bad gasket.

Agree on no sealer on a gasket (unless mating surfaces are damaged/warped). Any sealer is weaker than a gasket and sealer lets a gasket "squirm" outward as bolts are tightened and encourages a leak. I'm aware this is another controversial topic like anti seize on lug nuts or spark plugs. I just go with what works for me. YMMV, as they say...

 

[AshleyQuick]

If you do have damage on the surface you can forget the gasket and use Permatex Right Stuff or Ultra Grey. Follow the instructions carefully. Ultra grey needs setting time and The Right Stuff does not. Mostly likely you have a small section of old gasket that is not cleaned off.

I bought the Permatex black (but have delayed the install until Tuesday). They had the grey but I couldn't really ascertain the difference in the two.

 

[willbur]

I bought the Permatex black (but have delayed the install until Tuesday). They had the grey but I couldn't really ascertain the difference in the two.

Grey is thicker and meant for high torque applications i.e. doesn't squeez out

 

[AutoMechanic]

I bought the Permatex black (but have delayed the install until Tuesday). They had the grey but I couldn't really ascertain the difference in the two.

Black is fine that’s normally what I use.

 

[Chris142]

Yes, a 3.8

What are the elbows?

These. The oe are plastic.

 

[eljefino]

Not all water pump gaskets are the same. I've had cheezy paper ones that wouldn't handle a .005" scratch and I've had others that were like a tire rope plug-- thick and tacky/gooey. Obviously I like those with a little "give".

I'd ask the parts store guy to see multiple brands if he has them and pick the beefiest looking one they have. And follow the rest of the advice in this thread.

 

[Snagglefoot]

If you do have damage on the surface you can forget the gasket and use Permatex Right Stuff or Ultra Grey. Follow the instructions carefully. Ultra grey needs setting time and The Right Stuff does not. Mostly likely you have a small section of old gasket that is not cleaned off.

Both black and grey list water pumps. Black has more oil resistance, that’s all. The aim thing is to read the instructions carefully and do exactly what they say. Also realize they need moisture in the air to work, otherwise you need to wait a little longer. Pay attention to the bead size and go around the holes. Don’t go crazy on the bead diameter. Practise running a bead and measure it. Good luck!

 

[Ihatetochangeoil]

Follow Trav's advice and you'll be fine. Cleanliness is next to godliness on any gasket surface. My two cents to you is that you mentioned that you're not far from an Advanced Auto parts store; you need plastic razor blades. https://shop.advanceautoparts.com/p/dorman-help-plastic-razor-blades-5-pack-22018/21220001-P?searchTerm=plastic razor blades I've done water pumps on numerous 3800s....Never any leaks. Use plastic single edge razor blades to clean this area after using a solder brush to apply Permatex gasket remover to soften old gasket material prior to removal. If you don't clean your gasket surface thoroughly, nothing else you do is going to matter. Water pump gaskets for 3800 are basically heavy paper. I've used silicon grease on the back side (to the timing chain cover) so disassembly is easy should I have to do it over; but I never damaged the gasket surface. Best of luck to you.

Edit: At the risk of sounding overly simple, I have several types of lights; magnetic LED flashlights, battery powered fluorescents, drop lights, etc. You can't clean what you can't see, and I don't think it is possible to have too much light. You might even delight yourself by finding something obvious you missed under dimmer conditions....

 

[BlueOvalFitter]

Black is fine that’s normally what I use.

AM, you need to go over there and fix his water pump.

 

[AutoMechanic]

AM, you need to go over there and fix his water pump.

True lol and I am crazy I usually use the water pump kind for water pumps I must of been thinking oil LOL. I am too tired today to do anything else I fixed an APU unit on a Kenworth and put batteries in.

 

[tbm3fan]

A few days ago, our 2003 LeSabre threw off the serpentine belt because the water pump/pulley was rattling and spinning unevenly. Fortunately, this happened a block away from an Advance Auto so we were able to get it to their parking lot.

I bought a new water pump and installed it without properly draining the coolant. They weren't open at the time so It basically just drained out onto their lot as I was removing the old pump (mistake).

I was able to scrape off the old gasket with a metal wire brush so that I had a clean surface and installed the new pump, reinstalled the pulley and the belt and then filled with nearly a gallon total of new coolant and distilled water. I had no idea how much was in the system AND I filled in the overflow tank (assuming this was another mistake?).

So I then started with the overflow tank cap open and let it run for a few minutes with the heat on. The pump/pulley was now spinning properly but after several minutes, coolant was seeping out from the pump. I tightened everything down with the new gasket so what could possibly cause this new leaking? I just turned off the vehicle and came home to post this before further proceeding.

Well don't feel bad as you could have done what I did. It isn't as though I don't have an experience with changing water pumps ever since 1970 in my Cougar. Yet 18 months ago I finished installing my rebuilt heads, new camshaft and new lifters. Buttoned it all up and went out for a 25 mile drive after break in. Got home with no problems and notice a week or so later that there was a little drip under the car. Hose not tight enough? A bolt needing a little more? I take a close look, then another close look, and realize I left the water pump gasket off. So 25 mles with no leaks and then a slow drippy leak a few weeks later. That seal between the pump and timing cover must have been super smooth...

 

[BlueOvalFitter]

Does anyone out there know if the 3M Yellow (Super Glue consistency ) gasket sealant is still available?

 

[zrxkawboy]

Does anyone out there know if the 3M Yellow (Super Glue consistency ) gasket sealant is still available?

3M Weatherstrip Adhesive?

 

[Snagglefoot]

Haven’t seen it in a quick search. I like to use Permatex High Tack to hold the gasket and keep it from moving, putting it on the pump side only.

 

[Number_35]

Haven’t seen it in a quick search. I like to use Permatex High Tack to hold the gasket and keep it from moving, putting it on the pump side only.

View attachment 41242

I used to like the tacky red spray from Permatex for keeping gaskets in place during installation. I think it helped seal too. I think I still have part of a can left. Hope they still make it. I wonder if this is the same stuff in non-aerosol form.

 

[Snagglefoot]

I used to like the tacky red spray from Permatex for keeping gaskets in place during installation. I think it helped seal too. I think I still have part of a can left. Hope they still make it. I wonder if this is the same stuff in non-aerosol form.

Could be. It’s a deep red in color.

 

[Snagglefoot]

Most definitely it is the same stuff. At least in name.