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Just finished my 4.9 Water pump repair pics inside

13K views 6 replies 3 participants last post by  Night Wolf 
#1 ·
I was just stopping in to browse around and found a fury of threads about nightmares with the water pumps. So I decided to post up the info on my change.

It won't be the same as all yours as my 4.9 Eldorado motor is in a Fiero.

Well I was out driving the 85GT 4.9. I am suppose to be the guy that blows nothing but Trans axles. Of all places I am leaving Wally Mart heading over to find some computer parts. The parking lot is nearly empty I get that funky feeling in my right foot. I crank the wheels over, punch it and drift the car sideways through the parking lot. I stop at the computer place and get out of the car to find a trail of water behind the car. CRAP CRAP CRAP. I pop the deck lid can see water streaming out from the engine bay. I get a light and shine down to the pump only to find water spraying out from the pump to housing seal. Looks like I popped the gasket.

I have a fellow Fiero nut with me (in another car) We get in there with tools and find 2 of the 15mm bolts (same place as the leak) were totally loose. Were not even finger tight. We torqued them down, and filled up the cooling system, left the thermostat out and I drove it about a mile and a half and the temp started to climb again. I stopped, topped it up again and drove another 2 miles. I did this start and stop thing all the way home about 5 miles down the highway. I never let it get over ¼ on the temp gauge. As soon as I saw the temp start to rise I pulled over and topped it up. I was not about to let it overheat and blow the engine.

So it looks like I am going to have to replace the gasket. The water pump was new a year ago as I installed a new pump when I installed the engine.

I called the parts store and ordered the new gasket. They said it would be at least 3-4 hrs to get it from the warehouse. So I decided to get the pump off the car. I wanted to take lots of pics for future reference for other 4.9 water pump changes for other people.

There are 5 main bolt types.

10mm nuts on studs in the housing
10mm bolts in the housing
15mm bolts in the housing
Torx bolts holding the housing to the pump under the pulley
13mm bolts holding the pulley to the pump

Once the belt is removed everything can be done from the top in my car.

1st step is take a pic of your belt routing.
2nd step is remove belt by pulling tensioner back
3rd step is drain remaining coolant from engine
4th step is to remove 13mm pulley bolts
Then begin removing all the nuts, bolts, and Torx bolts from the pump housing
Carefully peel the pump away.
Total dismantle should take 20-30mins if nothing goes wrong.

I got it all pulled apart and headed to the parts store and the gasket they brought in for me was damaged and they are going to deliver a new one to me in the morning.


So here are the pics from the dismantle.

Socket Set


Gear Wrenches


Speed Ratchet. When collapsed, all you do is twist the handle and it removes nuts and bolts. Great for tight spaces where you can't swing a wrench or ratchet


Belt Routing and pump installed


Pump Removed Sorry I really could not take pics of each individual bolt


Blown gasket on back of pump


Pump impeller cap that came un-bonded. I have attempted a repair on it. Will post the results after driving on it for a week or two.


Pump housing with pump removed




This is from Day 2 after waiting for the parts store to get me my dang gasket.

I went ahead and put it all back together. I re-bonded the outer ring on the water pump. I am not going to say what I used to re-bond the cap on the water pump impeller until I know for sure it worked. But so far so good. The pump as far as I know only had a 1 year warranty and it is now about 14 months old. The parts store said it was the only style they carried and would not be able to get me a new one for a couple days.

I had the gasket in hand, a tube of blue silicone in the other and a 3rd tube of black silicone and gave it some serious thought. I have never in the 10-15 water pumps I have done on various Fiero’s ever had a failure using Permatex High Tack Spray Gasket with a Felpro Blue Gasket. So I went ahead and did it like I always do. I sprayed the back of the gasket, then laid it on the pump and sprayed the front of the gasket. The stuff comes out in a red spray with the consistency of hair spray.

I moved the pump into place, threaded in the 2 15mm large bolts and the 2 Torx bolts then started installing all the 10mm bolts and nuts. I think the hardest part of the job was trying to find all the dang holes. Once I got all the bolts in finger tight I went back around 3 times snugging each one down and making sure that I did not miss any nut bolt or other fastener. I let it sit and dry for about an hour and then added the water and put the belt back on. Thankfully I did take pics of the belt routing as sure as **** I had the belt going the wrong way and it would not go back on. Once I looked at my pic I realized when I had done fixed it and fired her up.

Burped the system and took her for a spin. Temp got up to where it was suppose to be and engine ran perfectly. I took it for a spin into town in city traffic and it never got hot. I pulled over, checked under the car and not single drop of water. In any case car is back on the road and running great.

The spray stuff I used is


The website is http://www.permatex.com/products/automotive/aut...

It has never failed me when using a Felpro blue gasket.

As for the possibility of the outlet gasket leaking. If it does start to leak I will replace it when I drop the cradle. I am going to be dropping it in a month or so to swap to a new trans.
 
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#3 ·
I have used the spray many a time. The nice thing about it, is that it never gets hard. So when it is time to remove the pump again, you just undo all the bolts and the pump will pop off. It is not a replacement for a gasket, you just spray it on both sides of the gasket before you put the gasket onto the pump. It soaks into the gasket and makes it much more pliable. (sp) The catch is that you need to use a quality gasket like the blue Felpro. The cheap junk cardboard based gaskets just get weak and blow out eventually. Using the cheap gasket that came with the pump was my mistake in the first place. I should have thrown it out and used a new Felpro right from the beginning.
 
#4 ·
I have used the spray many a time. The nice thing about it, is that it never gets hard. So when it is time to remove the pump again, you just undo all the bolts and the pump will pop off. It is not a replacement for a gasket, you just spray it on both sides of the gasket before you put the gasket onto the pump. It soaks into the gasket and makes it much more pliable. (sp) The catch is that you need to use a quality gasket like the blue Felpro. The cheap junk cardboard based gaskets just get weak and blow out eventually. Using the cheap gasket that came with the pump was my mistake in the first place. I should have thrown it out and used a new Felpro right from the beginning.
Thanks, Capt Fiero. Very nice pictures, BTW.
I noticed as soon as one replaces an original water pupm on a 4.9 one just keeps putting new ones... Probably people do not pay much attention to the quality and to the proper installation of the gasket. The OEM waterpump is about $60 at rockauto.com. I do not know wheter it comes with an OEM gasket.
 
#5 ·
The pump had the impeller cover busted off, and the cheap brown paper cardboard gasket is junk.

I have now driving the car for 3 days of abuse and stop and go traffic. The pump is doing great.

Now for the answer, what did I use to put the impeller cover back on.

Drum Roll Please


Krazy Clue. AKA Super Glue.

I cleaned all the surfaces, and put glue on each impeller face where it contacted the cover. I let it sit up over night and it bonded so well that it seemed like one piece of solid plastic. I searched through many different types of glue and honestly the Krazy Glue seemed be the best suited for bonding 2 pieces of hard plastic together in submerged in hot water.
 
#6 ·
The pump had the impeller cover busted off, and the cheap brown paper cardboard gasket is junk.

I have now driving the car for 3 days of abuse and stop and go traffic. The pump is doing great.

Now for the answer, what did I use to put the impeller cover back on.

Drum Roll Please


Krazy Clue. AKA Super Glue.

I cleaned all the surfaces, and put glue on each impeller face where it contacted the cover. I let it sit up over night and it bonded so well that it seemed like one piece of solid plastic. I searched through many different types of glue and honestly the Krazy Glue seemed be the best suited for bonding 2 pieces of hard plastic together in submerged in hot water.
Hopefully Super Glue will last. Do you remember what size were the torx bolts?
 
#7 ·
Leave it to GM to have 5 different sizes/types of fasteners holding the water pump on.

I never had to do that to the Coupe before it was stolen... I was going to do it within that month too, as preventative maintenace.

When the water pump in my '89 Oldsmobile (3800) went, the bearing was shot and the impeller broke off.
 
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