LT1 Water pump replacement help
LT1 Water pump replacement help Going to change my water pump in my 96 z28. It has been leaking from the engine side of the water pump? Not out of the weap hole to my surprise.
Do you have any tips besides making sure to replace the 2 ring gaskets, temp sensor, and maybe throw in a 160 degree thermostat so when I get it tuned I can have the fans come on earlier so the engine will run cooler?
Have any of you changed the water pump drive seal while replacing the waterpump?? I'm hoping the opti will be okay, it had a little antifreeze head its way but it is the vented opti and no drive issues yet.
Do you have any tips besides making sure to replace the 2 ring gaskets, temp sensor, and maybe throw in a 160 degree thermostat so when I get it tuned I can have the fans come on earlier so the engine will run cooler?
Have any of you changed the water pump drive seal while replacing the waterpump?? I'm hoping the opti will be okay, it had a little antifreeze head its way but it is the vented opti and no drive issues yet.
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OP
from this side of the internet we can't see your point of leak. you describe it as 'engine side" but not weep hole. It is possible the gaskets between pump & block have failed (rare)....or the lower DS bolt did not get thread sealer (that bolt goes in water jacket) from a previous WP replacement
If your coupler "easily" slides of the WP drive gear spline and the WP drive seal shows no signs of leaking you can leave that seal alone. With that said you had some form of WP leak so I would pull the Opti and remove cap to inspect inside for any sign of coolant contamination. At that point the WP & Opti seals are right there and a $12 FelPro TC gasket/seal kit has all you need to replace them. If you are not confident or have the "tool" to install the WP drive seal...maybe leave it if not leaking.
If there is coolant inside of Opti, replace Opti vent harness as the check valves in it are most likely clogged from coolant
from this side of the internet we can't see your point of leak. you describe it as 'engine side" but not weep hole. It is possible the gaskets between pump & block have failed (rare)....or the lower DS bolt did not get thread sealer (that bolt goes in water jacket) from a previous WP replacement
If your coupler "easily" slides of the WP drive gear spline and the WP drive seal shows no signs of leaking you can leave that seal alone. With that said you had some form of WP leak so I would pull the Opti and remove cap to inspect inside for any sign of coolant contamination. At that point the WP & Opti seals are right there and a $12 FelPro TC gasket/seal kit has all you need to replace them. If you are not confident or have the "tool" to install the WP drive seal...maybe leave it if not leaking.
If there is coolant inside of Opti, replace Opti vent harness as the check valves in it are most likely clogged from coolant
Do I have to remove the fans for room to get the water pump or the whole radiator? And does the car have to be jacked up? I know I have to drain 15 quarts out of the radiator. This opti stuff just pisses me off thinking about it. I don't really have the money right now for a water pump let alone a new opti. So I got to run the opti until it grenades!
I'm also going to try and tighten the bolts to see if that stops the leak but I bet it just gives the opti another shower when I drive the car!
I'm also going to try and tighten the bolts to see if that stops the leak but I bet it just gives the opti another shower when I drive the car!
You don't have to remove the fans or radiator, i didn't. it would help with the limited amount of space you have to work with though. and the bottom water pump bolts are easier to get to if you jack up the car and get at 'em from the bottom. good luck with the fix! 
Teching In
Joined: Aug 2014
Posts: 21
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From: Charlotte
You don't have to remove the fans or radiator, i didn't. it would help with the limited amount of space you have to work with though. and the bottom water pump bolts are easier to get to if you jack up the car and get at 'em from the bottom. good luck with the fix!
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Joined: Jan 2013
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From: Thibodaux LA
i removed the fans when i did mine. not that hard and freed more space. id look at new gaskets and put sealant on the proper bolt threads first before getting a new pump. dont forget to put the shaft connector back on(combines the pump gear to the cam gear). i didnt and couldnt figure out y it kept getting hot when i tested it out. felt like a idiot once i realized what i did
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Verdad Gallardo Update, I got to the waterpump today and starting pulling off the hoses from the waterpump. Once I pulled the bottom hose off of the WP antifreeze started draining out??? I drained the antifreeze from the radiator but it appears the block has tons of antifreeze in it still, I don't want to pull the WP and watch a gallon of antifreeze dump on the opti
Problem is that I drained the radiator once the car was up on ramps for the job. Is there anyway I can drain the antifreeze out of the block while the car is on ramps???
Which bolt threads do I need sealant on and what type of sealant do I use?
Also the thermostat housing cover had a gasket on it to my surprise when I pulled it off? I thought all you needed was just the gasket that it built into the stock thermostat??
Thanks for any help! You can tell I am a novice mechanic lol
Extra tough working on a LT1!
Problem is that I drained the radiator once the car was up on ramps for the job. Is there anyway I can drain the antifreeze out of the block while the car is on ramps???
Which bolt threads do I need sealant on and what type of sealant do I use?
Also the thermostat housing cover had a gasket on it to my surprise when I pulled it off? I thought all you needed was just the gasket that it built into the stock thermostat??
Thanks for any help! You can tell I am a novice mechanic lol
Extra tough working on a LT1! TECH Enthusiast
Joined: Jan 2013
Posts: 686
Likes: 76
From: Thibodaux LA
just back it off the stands. drain more coolant out and drive it back up on the ramps. it will be able to run for the 30 seconds to get it back on the ramps even with out the coolant in it. when you take the pump off you can see which holes need sealant. just go to any auto parts store and look for thread sealant. its in a white tube. make sure you read this http://shbox.com/1/4th_gen_tech2.html#radflush for how to refill so you dont get any air bubbles.
yea i remember when i first bought an LT1 and had to do the water pump 3 times (because i was a noob with the gaskets) before the opti went. then i had to do it again lol! don't worry pretty soon you'll have it down like the back of your hand, we all start somewhere 
) before the opti went. then i had to do it again lol! don't worry pretty soon you'll have it down like the back of your hand, we all start somewhere Update!!!!! After about 5 hrs of little problem after little problem I got the water pump off!! Have a few questions,
1. Do I need to replace the WP driveshaft seal that comes out of the timing cover, it shows signs of tiny bits of oil around the perimeter. My fear is it needs replaced. Where would I find a good quality seal to go in there? Is it a hard job? What tools do I need? It would suck to get the car back together and watch that seal leak
2. The new WP has a new o ring seal on its shaft, do you know what size the o ring for the camshaft drive shaft is? Do you grease the coupler and O-rings up when installing or do you leave them dry?
Opti looks okay, it is a 96 sealed unit so hoping it has some life left in it since the car has 84,000 miles, hoping for maybe 120 to 140,000 miles out of the stock opti
1. Do I need to replace the WP driveshaft seal that comes out of the timing cover, it shows signs of tiny bits of oil around the perimeter. My fear is it needs replaced. Where would I find a good quality seal to go in there? Is it a hard job? What tools do I need? It would suck to get the car back together and watch that seal leak
2. The new WP has a new o ring seal on its shaft, do you know what size the o ring for the camshaft drive shaft is? Do you grease the coupler and O-rings up when installing or do you leave them dry?
Opti looks okay, it is a 96 sealed unit so hoping it has some life left in it since the car has 84,000 miles, hoping for maybe 120 to 140,000 miles out of the stock opti
as long as you keep the opti dry it'll last - my stock opti lasted till 202K miles when the pump gaskets blew and drenched everything. when i replaced the gaskets all i did was put lithium grease on the coupler and loctite on the bolts, then followed the torque procedure. i'm sure someone else will chime in with their experience. i wish you luck on you water pump journey
Id also like to know the procedure for doing the seals for the opti and wp while still in the car. I seem to have developed a small leak from one or the other....I cant tell which, so Ill just do both.
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Joined: Dec 2008
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From: Little Rock, AR
Well now I am beginning to realize what a PITA a Lt1 is. My opti is in the way of my WP drive seal by about 1 cm. So if u want to change the $1 seal you have to pull the opti, drive belt, and somehow rip off that crank pulley with a tool that I don't have. I don't give a sh** anymore I am going to slap it back together with the original WP drive seal in place and hope it don't leak which of course it will because of murphys law. Mite as well rebuild and pull the whole engine when you have to change a water pump, stupid a$$ design. Lets not forget about the retarded opti location, oh don't get fluid on the opti "impossible!!! You cant stop fluids from dripping on it.
Oh how I wish I would of bought a LS1. Even better I would like to drop a TSBC in there.
Oh how I wish I would of bought a LS1. Even better I would like to drop a TSBC in there.
Last edited by 350 groundpounder; Oct 10, 2014 at 05:55 PM. Reason: Ou