Going to try and document replacing a 455 water pump for the novice, from a amateur pov.
Thread will develop over next couple weeks. I am doing my timing cover at the same time.

Will be listing all the threads Ive found, and info during my research to hopefully make this a one stop shop for 455 water pump jobs...and a little bit about Timing covers, all for the novice.

Im a rookie, so I have no problem in being corrected when wrong!

Still researching which pump to get, which is tricky enough. Going to list all the options I can for you in choosing the pump-allot of options. I will only be doing A\C cars, focusing on my year 71-72':
(will be adding to this list each day)

GMB -
Cast Iron - Standard flow - A\C
http://www.summitracing.com/parts/GMB-130-1260/

Cast Iron - Hi flow - A\C
http://www.summitracing.com/parts/GMB-130-1260P/

Aluminum - Standard Flow
http://www.summitracing.com/parts/GMB-130-1360/

Aluminum - Hi Flow
http://www.summitracing.com/parts/GMB-130-1360P/


Some of these above can be had for less at Advance Auto as some have posted on C.O. and Ive verified.


TUFF STUFF -

Cast Iron - Standard Flow - A\C
http://www.summitracing.com/parts/TFF-1504NB/


CARDONE
Cast Iron - High Flow...?? - A\C
http://www.summitracing.com/parts/AAZ-58-295/

Note the difference in impellers!




Cast Iron - Standard Flow - No A\C
http://www.summitracing.com/parts/AAZ-58-294/




FLOWKOOLER
Aluminum - High Flow - A\C 6.0 inch
http://www.summitracing.com/parts/BRA-1775/

Aluminum - High Flow - A\C 5.6 inch
http://www.summitracing.com/parts/BRA-1776/


MILODON
Aluminum - High Flow - A\C 6.0 inch
http://www.race-mart.com/Milodon-MIL-16285.html

https://www.yearone.com/Product/DisplayProduct/350638

 

Make sur if you have AC,you get one for Ac, as the leanght is different on non AC. Also, I would try to find one that has a cast impeller, not stamped steal. Most cheap ones are stamped steal. I would go to a good parts store and see what they sell, and then you can see it before you buy it,stamped steal loos like a fan, and the cast is a wheel type with cups.

 

Thx...I got a thread to post on topic of pump lengths. Its a famous thread referred to often around here.

The threads around here I have read calls them closed impellers vs open impellers

The whole topic of open vs closed impellars will be a good investigation project. I got a ton of photos Im going to post of different water pumps, including some impellers Ive collected.
Thx for input.

 

In addition to the overall distance from gasket surface to pulley mtg flange, check the OD of the inlet nipple.... ESPECIALLY on 71-2 cars, as they were in a transition period...and both 1.75" and 2" inlets were used. Wrong one, and your radiator hose won't fit right.

 

Water pump pics

Open Impellar - Standard Flow





Closed Impellers - High Flow
(Not a 455 pump here)




Note the closed impeller design on this one. It seems all one cast here vs the Milodon design. It seems this design here is much more sturdy.




Here is the Milodon version from what ive read on this site is just a GMB pump with the Impellar change and shield welded onto it, at more than twice the cost.


The Milodon version above has more impeller blades than most out there.

Here is one of the GMB version 455 pump impellers.

 

Nice shot of a closed impeller off the pump-

 

Thx for the info. One of the thread links Im going to post also mentions this.
I just bought all new hoses, so I will have to make sure of diameter, though a hose is pretty easy to swap out.

Another issue to consider is the inlet angle....some are straight and some are bent like originals.
I think one of the threads I have saved goes into this too. Like to know the skinny behind that too.

 

Has anyone seen a cast impeller on a new or rebuilt unit? I've only seen them on old cores. Every water pump I've bought in 15 yrs has had a stamped impeller.

 

Thanks for this thread, I've been following it closely.

I'm in the "Newbie" category to Olds and Cars in General. Looking to replace the water pump in my 72 Cutlass S. Stock 350, etc.

 

I had to do this on my AC 70 SX a while ago and also typed up a "step-by-step" if it helps:

http://www.oldsmobilecentral.com/201...70-cutlass.php

 

What'd you do with that 400268 WP you took off?

 

I sent it along with all the other original parts with the car when I sold it

 

Scored this interesting WP on epay last week...

http://www.ebay.com/itm/261074469442...84.m1439.l2649

AL body
"G" Logo?
5.6 x 1.75" unit
Note the CAST IRON 6-blade impeller!
Seller says it has been on his shelf for many years.

 

Hey Oddball. Im no expert, but I spent ALOT of time out there looking around, web searches, tons of images, and I have not seen cast impellars on any newer pumps. But I also havent read anything about the impellars failing either. I have read alot of these newer pumps failing sooner rather than later leaking wise.


Well there you go! No need to finish this thread!
This is funny as I have your thread as one of the ones I was going to post!
Good job there. Thanks for posting it.
I will just add more photos for the weekend warrior.

I got all the gaskets now, New timing cover, new bolt kit, etc.

I havent gotten the pump yet, been very busy. Ive been considering the Milodon 16285 as its Aluminum, Hi flow, has closed 8 impellar setup.
It has straight inlet tube, which is not like my original...will need to look into that.

The timing cover\water pump gasket kit I got is Felpro - FEL-PRO TCS 45270

Oil Pan - VICTOR REINZ OS30534TC (Steel mesh Diesal 350 gasket)

Will be getting into this next week or two.

 

Well, hows that for timing! Just as I say I havent seen newer style pump with Cast closed impellar one shows up! 12 years new though...

Any numbers on it? Be interesting to track down what brand it is.

 

No numbers, just a teensy "G" about 3/16" in size...

 

I just bought a FlowKooler unit and it has a "G" on it. The impelller on mine is not cast iron, though. Could be a pretty rare pump.

 

Im doing the Timing Cover and oil pan this w\e.

Some notes I found from Joe P:

"You DO NOT need to remove the oil pan to R&R the front cover. It is possible to simply loosen the oil pan bolts (more towards the front than the back) and work the cover back into place. There are a couple of tricks, as described in the Chassis Service Manual. First, the rubber seal that fits into the bottom of the front cover has ears that are clamped under the oil pan. These ears must be cut off on the replacement seal to facilitate cover installation. Second, the seal should be gooped up with RTV, particularly at the corners where the seal was trimmed. Now, place the bottom of the cover into place with the top held away from the block. Angle it into place on the two dowel pins on the block. You may need to gently pry down on the oil pan. I use two of the front cover bolts to actually pull the cover into place. Once seated, you can install the bolts and water pump normally."
___________

In my case the entire pan is lowered as Im replacing oil pan gasket too at same time, due to some leaks.

Timimg gear cover...included are pics of the proper bolts in their proper places. Can get confusing.

New and old Cover, New seal installed


Did a mock up first with old TC and pump just to get all the bolts right, make sure everything lines up.



Once I got everything right, took it apart to take pics of proper bolt setup.
There is a strange arrangement of bolts here, with 5 different bolt types. Here are plenty of pics to get accurate setup

 

4New set of bolts from ILT on Left, Old mismatched and rusty bolts on Right



Various angles of correct bolts









Then I took old TC off, and installed new one using black sealant, and water sealant around water ports. I used various shorter bolts
as needed because Im not installing Water pump at same time as TC because Ive still not totally made up my mind on which water pump
to get. Not happy with any of these parts store mass produced chinese pumps. So I button up engine till I decide, then install pump later.

 

Hey JC any reason you removed your last post on difficulty of oil pan gasket removal. Got an email notification but no post...would have liked to see those links to the before and after. Good thread.

 

Sorry man I had post the whole thing in the wrong section. I was working on 3 different threads last night updating them. I put the oil pan update in the timing cover/ water pump thread. I moved it. I'll post the correct link for you. It's in my restoration thread now .
https://classicoldsmobile.com/forums...s-s-455-a.html

Back to TC install:
I used 400 grit to clean up crankshaft end, and then oil up New Harmonic balancer and crankshaft, and installed with Harmonic Balancer install tool




Torqued HB to specs

Make sure you have your research laptop setup with Billabong ASP Surf contest live from Teahupoo Tahiti running in background

 

As I already mentioned, Im not too happy with the selection of current water pumps out there. The Parts stores carry allot of lower end stuff. And the newer construction is no where near the old designs - cast vs stamped steel as described above.
I went with the Milodon 16285 mostly because though its stamp, its Hi Vol and more impellars than others. It seems to have the best of the modern features, although its still wanting in my eyes.
Its pricy, but I will try it out and post what I think.

 

Milodon is a modified GMB:

 

I used studs here as a guide. Make sure they are long enough!

 

Here is another pic \ layout of the proper special bolts you need. 4a is noted due to option of one shown or the special double sided threaded bolt like #5, depending on power steering bracket setup, etc:

 

Finally got around to fixing all the errors in this thread due to pic formatting crash back in Sept.

I got the special privilege of redoing the water pump because one of the ILT bolts in the set (double sided bolt) snapped at only half the torque spec! I quickly fixed it back then, but damage was done. It sprung a tiny leak right at that bolt spot. So beware with those ILT or similar repop bolt sets sometimes. I ended up using the original double sided thread bolt, which was one of only two originals the car came with.

 

You did check the timing chain, didn't you?
Hate doing things twice!

 

Yep. She had a fresh rebuild 200 miles ago. PO just put a ratty pump back on. Thx.

 

"one of the ILT bolts in the set (double sided bolt) snapped at only half the torque spec!"

Huh, you don't say...

I'll just let it go at that for now.

One reason I prefer used factory parts, including fasteners.

 

Didnt have much chose as all except two bolts were shade tree, stripped, unusable (to me anyways). The other bolts in the In Line Tube set are all good Grade 5 or better. So its jus the double threaded bolts that are questionable in the set. IT was the thinner one by the way that snapped...the thicker lower one on timing tab worked fine.

 

I am looking for a water pump. Looked at two new pumps , the heater hose nipples are now cast with the bump body. What happed to the pumps with pressed in tubes for the hoses (as I have now). Were the factory pumps made with pressed in tubes for the hoses., I though they were. Has anyone bought a pump in the last month that has the pressed in tubes for the header hose, if so who sells it? Thanks..