Water Pump and Timing Chain

G

Greg C.

Active member
Oct 11, 2019
256
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Now that my radiator is out (taking it to the radiator shop tomorrow) I need to change the timing chain, water pump, fuel pump, etc., etc.

I've read and printed out the maintenance manual pages, looked at Carl S's pictures, read Gene Fisher's info, and done several searches of the forum.

I would like some opinions on a couple of items.

1. Use the oil pan to timing cover rubber gasket, or RTV?
2. Use the GMB water pump, Flowkooler water pump, Dayco water pump (can't find this one now) or a different water pump?
3. What "gotchas" might I run into that have not been discussed in the above mentioned literature?

Thank you.
--
Greg Crawford
KM4ZCR
Knoxville, TN

"Ruby Sue"
1977 Royale
Rear Bath
403 Engine
American Eagle Wheels
Early Version Alex Sirum Quad bags
 
use the oilpan to rubber gasket. razerblade carefully the little triangle outcroppings that are supposed to sandwich between the oil pan and the
block. I have heard some say you can loosen up oil pan bolts, but I just see that as a messy oil pan gasket leak in the future if you disturb the oil
pan to block gasket/seal. Use black RTV on the corners where that meets. also use black RTV on the upper paper gasket of the timing cover.

I make a couple studs. put those in the block and I use a Nut on those studs to work/press the chain cover in place in a controlled manner.
bottom in 1st and let it tilt upward. I also file the top edge of the 2 guide pins a little to help that transition. I recommend just getting the
timing chaing cover sealed and in place, let that dry till the next day, then go back day 2- and mount up the water pump.

I also made a straight edge with a cutout for the crank. so you can put that across the timing gears and be certain they are lined up. Sometimes
just visualizing you tend to question if you are a tooth one way or the other.

I also recommend a new harmonic balancer. the old one usually has a grove that won't match with the new oil seal, and even though there is a
bushing for the end of the balancer with some kits, I have never had luck getting the bushing on the balancer.


--
Jon Roche
75 palm beach
EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
John:

Thanks for the reply. I was beginning to think no one was reading. I will do as you suggest and use the rubber seal.

I do plan to get a new harmonic balancer, as experience has taught me those things can slip when bathed with oil for decades. I've read so many
opinions on timing chains and water pumps. I'm going to get the

Cloyes true roller, overkill though it may be. I was going to get the flowkooler water pump, but woe unto you if you try to decide which one to use by
looking at their website. The Cardone pump is NLA, the

Dayco HD pump is NLA now, at least, not quickly, so I will go with whatever Jim K sells me. The stainless 3/8" trans cooler lines (mine were very
rusty and twisted apart) and the stainless flexible oil cooler

lines are also going in, as well as a new front motor mount. I have a 307 aluminum intake, the correct casting number, that will go on along with new
t-stat, all hoses, belts, sending units, etc. The aluminum

intake is not necessary, but the heat crossover blocking plates need to be installed anyway. My radiator is at the shop, getting re-cored with 16 fins
per inch, four row. That should cool it just fine.

Any suggestions on how to flush the engine block while everything is open?

Ordering parts this afternoon. Thanks again!
--
Greg Crawford
KM4ZCR
Knoxville, TN

"Ruby Sue"
1977 Royale
Rear Bath
403 Engine
American Eagle Wheels
Early Version Alex Sirum Quad bags
 
When you deal with the water pump and have the timing cover off. antifreeze will drop down and get into the oil pan. you will want to drain the
oil and leave the plug out. then dump a gallon of cheap oil in after all is said and done and let that drain out to flush what you can out of the
front of the oil pan. then put the oil plug in and fill up the oil. No matter what you do, some antifreeze is going to go down the front of the
engine and get into the front of the oil pan. you can pull he block drains and such too. I never really flushed the block ever. not really sure
the best method to do that with everything apart.

I have no suggestions on the water pump. water pump part availability changes way too often. One thing with the water pump, is to make sure your
pullys are square, and you have good belts tighted up properly.
--
Jon Roche
75 palm beach
EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
Please send me photos of the tranny cooler lines you end up with. I installed a rebuilt tranny and went to 3/8" tranny cooler lines last year.
bending them and getting that all to work was way more of a chore then I had anticipated. I spent twice as long dealing with making the tranny
cooler lines then it took me to install the transmission. 403 is probably different then a 455. I ended up pretty much the same stock tranny cooler
lines from the transmission to the final drive. where i did wrap them in a heat sleeve to help with the header heat. Then ended up transitioning
to high pressure braided flexible lines at that point.

--
Jon Roche
75 palm beach
EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
St. Cloud, MN
http://lqqkatjon.blogspot.com/
 
I ran my trans lines up over the trans bell housing. Then over to the passenger side frame rail, and a straight shot to the radiator. Also, in
anticipation of possibly having to remove the trans at sometime in the future, the pieces coming out of the trans I made only 18" long (or so) then
put a coupler on and ran second piece from that coupler to the radiator. So that coupler was at the top the trans and in full view and accessible from
the hatch. A lot easier to take that coupler apart for removing the trans than trying to reach down to the trans and start/unscrew the flared fitting
in the trans. Makes it easier to put it back together also. JWID
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Jon pretty much covered it. I used a GMB "heavy duty" water pump when I did my engine overhaul 45,000 miles after doing the timing chain etc. The
pump has not given me any trouble.
--
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles,
Solar battery charging. GMCSJ and GMCMI member
 
I had better luck with the GMB then the flow cooler .with the flow cooler I had overheating problems. I would drain the block before pulling the pump
so coolent doesn’t end up in the front sump of the pan. For sure don’t jack up the engine under the pan or it will push up against the oil pump
intake. I loosened the front pan bolts and used permatex to reseal it. Cloyes chains are less apt to stretch.
--
Roy Keen
Minden,NV
76 X Glenbrook
 
Thanks everyone. I ordered the water pump from Jim K yesterday. Took the old water pump and the harmonic balancer off today. Big groove in the
balancer, ordered another one.
--
Greg Crawford
KM4ZCR
Knoxville, TN

"Ruby Sue"
1977 Royale
Rear Bath
403 Engine
American Eagle Wheels
Early Version Alex Sirum Quad bags
 
Jon: I will take some pictures of the transmission cooler lines and send them to you when I receive them. They are scheduled for delivery on Friday,
if FedEx doesn't deliver them to the wrong house again.
--
Greg Crawford
KM4ZCR
Knoxville, TN

"Ruby Sue"
1977 Royale
Rear Bath
403 Engine
American Eagle Wheels
Early Version Alex Sirum Quad bags
 
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