costpenn

I'm doing a 72 455 non A/C with H.D. cooling - which of these fan shrouds (if either) would be correct? The main difference seems to be one has as extra vertical rib running along the outside.

costpenn

Anyone?? I think the ribbed one is correct.

2blu442

I've seen more with the additional rib but don't know enough to say which is correct for your year. Can you find a part number or date cast in either of them? I know I've found numbers and the two digit date in shrouds before.
John

Tony72Cutlass'S'

Hey Joe,

Where did you get your fan shrouds?? I've been having trouble with my cutlass that it really heats up towards 220* when i let it sit at idle for a long time...

costpenn

John, the ribbed one has 407867 on it, the other one has no numbers I'm able to make out.

costpenn

Tony - if you'll cover the freight, you can have the one I dont need.

2blu442

Just for grins I logged onto the Fusick web site and downloaded their catalog. They have them on page 48. It says for 1968-70 they have NOS GM parts, while supply lasts for $149 each. Part number 402995. Then for 1971-72 they have a repop with part number 407867 for $119. These numbers sound like the GM numbers so I'm betting the extra ribbed one is correct for your 1972. John

Allan R

John, Costpenn
I just looked up the shroud in the GM Parts Manual
Group 1.277 Part number 402995 is pretty much the part you want for 68-72. Even for CAC and HD cooling. Don't know what CAC is but I suspect it has something to do with emissions in Kally four nya

I just went an looked at mine. It has the part number inside the fan area with the date code stamping. It's 402995 and it doesn't have that extra ridge molding

oldsmobiledave

You will need to scare up the top plate if you want to run a shroud....it is different than the one used for non shroud applications.

Allan R

Tony, like Dave said the rad top plate for a shroud needs mounting bolt holes on the top. BTW, you will also need to weld or bolt lower mounting brackets to the lower rad support to hold the bottom of the shroud too. Make sure you 'dry fit' the shroud so there's fan clearance. The AM shows the shroud to be adjustable on vertical height by shimming the upper mount area.
Similar to this 4 core in top plate, you can see where the shroud bolts to the top plate.

Tony72Cutlass'S'

Cool! Thanks Joe! Definitely let me know whenever you make a decision.

I'm in no rush since i need to change my timing set anyway. Apparently my chain jumped a tooth

Al, Have you been hiding a 70 w-30 in your garage and not telling anyone! that engine bay looks stellar

Tony72Cutlass'S'

Hmmmmmmmmm, My top plate looks like this...

Allan R

Good you found it now! I can hear the sound of the drill as Dr. Tony sits the poor Cutlass in the chair for it's first root canal.......

Shhh, you'll ruin the surprise - it's not a 70, it's a 71

Ok that's not going to work. Even if you cut the holes in the top, it doesn't have the raised 'bumps' in the top to help properly seat the tabs on the shroud. You have a 3 core rad. Here's what it should be (sorry the pic is blurred but you can see what I'm saying)

Tony72Cutlass'S'

You know, I'm so impressed with Rockauto, i ordered my chain at 10am this morning, it's already 60 miles away from the delivery location in Champlain NY.

Now THATS what i call service.

Allan R

You have any problems getting that balancer pulley off? Hope you took pics of before so we can see that on your build. Don't forget to clean and paint the front parts of the engine while you have the chance. All new belts and rad hoses going back in, right?

Tony72Cutlass'S'

Havn't tried the balancer pulley yet...

I'm currently fighting with upper pulley in back of the fan blade. The previous owner put a 3'' spacer between the fan and water pump pulley ( i guess to get the fan closer to the rad) and i can't get it off for the life of me. He used longer bolts and there's a shaft going all the way through.

Very odd setup..

Allan R

Check to see if there are nuts on the near side of the engine. Take them off. Then just use a hammer and lightly start tapping all the way around the spacer to loosen it enough so you can wedge it out from the water pump. May as well replace the water pump while you're at it. How did you know you'd jumped the chain and there was a tooth broken? You look through the fuel pump hole?

Tony72Cutlass'S'

Hey Al,

Yeah exactly, i put my finger through the fuel pump hole and it was REALLY loose, there's actually a check in the CSM you can perform to see if your cam is in sync with your crankshaft by measuring the height of pushrod #4.

Also, my first hunch was my timing jumped by about 35 degrees

So i ordered the gasket/seal set, timing set, and water pump, all for 58 bucks shipped to my P.O box in champlain.

Tony72Cutlass'S'

I posted my troubles in my old Carb thread.

New carb won't start 350 rocket

Allan R

Yeah, I see that on 6B-31 of the CSM. How did you determine 35°? It will be really interesting to see how bad it really is when you get that water pump and chain cover off. You will need a puller to get that balancer puller off. I think the nut that holds it is 1 1/8" socket and a lot of torque. It's on there with a minimum of 160 ft/lbs - see page 6B-40. The water pump pulley might be stuck, but nothing a hammer can't fix if you bang it all the way around.

So was the car running poorly? All this stuff you're doing - incredible. That car owes you its life. Your Dad must be so proud of what you're doing, I would be if you were my son!

Allan R

Ok, I see now - went back and read through that thread. That's totally consistent with my experience of a jumped timing chain on our 67 Cutlass. Exactly the same symptoms. When you get the new gears and chain in, properly lined up and set for #1TDC I bet you get instant start and proper idle. Right now you're prolly gettin spark just as the intake valve is opening and it's backfiring through the carb.

FWIW that 75 HEI might have the wrong curve, but you can prolly just adjust your timing to suit. That's what mine is too. You can also hook up your Charcoal cannister - it has nothing to do with any vacuum loss. It just sends unused gas vapours back to inlet at that tank behind the rear seat. You have your TCS and vacuum lines all hooked up too? Had to figure out how the routing went for one of the guys here in AB who also has an Edelbrock on his 71 Delta. I think I can find that link if you need it.

Mr Shifty Sidney

Just as others have said, I think the 407867 will work. There are some physical differences between the 70 shrouds and the 71/72s. I can not remember exactly what the differences are.

Don W

Tony72Cutlass'S'

Funny thing Al, my dad's never actually seen the car, so i think he doubts it's actual existance...

Well, what was basically happening the whole time i've had my car, is that all of a sudden i'd try to start it some days, and it just wouldn't catch, i'd check the timing with my light and it would be WAY after top dead center.
So my only guess is that the car has skipped time before, and then skipped back and run OK for a little while.

Either way, the timing belt NEEDS to be done, and i'm replacing it with a Cloyes which is supposedly top of the line for our Olds engines. I'll document it in case you need to do the same on your car.

Allan R

??? Then why does the GM parts manual quote the same shroud (402995) through the years for 68-72 Cutlass/442?

Tony72Cutlass'S'

Hmmmmmm, maybe it was a difference like between 70 and 71 like with the ripples on the cutlass fenders?

I'm curious, do they show two different part numbers for the fenders, or one like the fan shroud?

Allan R

Interesting question Tony. Answer: No. The front fender for 70-72 is listed in Group 8.130 404718 LH and 404719 RH. Obviously though the 68/69 fenders are also listed as the same for their years (same group) 230796 and 230797.

I'm guessing here, but the basic metal for the fender didn't really change. All that was added to the 71/72 fenders was an extra stamping on the side rail prior to spot welding. Therefore the overall product didn't really change. What I've noticed about a lot of GM parts is that if they had a major structural detail change, the part number changed. Like 69/70 hoods - they look similar from a distance, but are aa completely different stamping/tooling up close. The 71/72 hoods use the same part numbers and are significantly different from 70. Just a thought.

Mr Shifty Sidney

My parts catalog from Sept. 72 shows different part numbers for the 70 and 71/72 shroud.

70 402995
71/72 407867

GM may have consolidated to one one part later on, what year is your catalog from? Also a note to remember when referring to items in the parts catalog. The catalog does not represent what came on your car originally. It is the part that GM offers as a replacement. The replacement may or may not be the same as what came on the car when it left the factory.

Don W

Allan R

Don,
I have 2 versions - a 72 and 83. I use the 83 version a lot though because it is electronic and easier to find stuff, so it may have the consolidated as you suggest. I did check the 72 version and the numbers you quoted appear there just as you posted.

Interesting. FYI the fender numbers that I quoted ^^^ were the same in the 72 version as the 83 version. More and more curious. I have found that many of the parts I look up in the newer version do match the ones listed in the earlier, unless there was a part changeup number - fairly common back in the day.

Well here's hoping there's no significant difference in the fitment of these 2 units. I'm really curious now to know what the difference is. You thinking it could be that extra rib in the molding? Or is it the mounting tab areas of the shroud? Either way they both look like they would fit from the pics posted earlier. Thanks for drawing those 2 numbers to my attention; I guess it would be a good idea to cross check the numbers occasionally.

Tony72Cutlass'S'

I may have found a new top plate not far away from me, fellow on this site is selling a drive quality one i could refinish.

https://classicoldsmobile.com/forums...op-plates.html

Allan R

Yeah Stan has some nice stuff. Before you commit to buy, have a look at this:
http://www.ebay.ca/itm/1971-Olds-Cut...#ht_500wt_1040 A little clean up and cosmetic work, and for the price???

Tony72Cutlass'S'

15 bucks sounds like a great price, but he said he's open to offers so i offered 30 shipped to my US PO box for the driver quality one.

I'm really excited if this solves my ever-overheating problem.

Another fellow on CO installed a shroud not long ago (we have the identical setup) 72 350 with edelbrock 1405 carb. Supposedly the shroud really helped.

Allan R

The fan shroud and HD cooling will make a big difference. I think the biggest improvement will come from when your timing is set right. If it was too far retarded to start with, that engine would likely run pretty hot. Got my eyes crossed for ya bud!

Tony72Cutlass'S'

I JUST GOT MY FAN PULLEY OFF!!!!

Stupid spacer was seized onto the hub. Nothing like a little bit of coaxing with a wood splitting wedge.

Allan R

Wow! Sounds like the resto of your car is fighting you every step of the way. All of a sudden I'm scared of what you're going to find with the crank pulley and nut. We should take this stuff over to your build thread instead of jacking this one any more.