1973olds98

i have the 1973 olds service manual but there isnt any good pics of the vacumm routing hoses..If anyone out there has a 1973 olds 98 with a 455 could u please remove your air cleaner and take me some good pics of the engine where i can see the vacuum hoses...thanks

jeffreyalman

maybe the same as a custom cruiser? look for jaunty75

jaunty75

Man, this guy wants EVERYTHING! First it was pictures of where the oil pressure and water temp sensor wires go. Now it's vacuum hoses. What will it be next?!?! Which way do the headlights face? Which side does the steering wheel go on? When will it ever stop?!?!


No problem. Let me take some photos tonight and post them.

1973olds98

Isnt this what this forum is about helping others..I will continue to ask questions that i need help with. And would do anything I could to help anyone out even if thats taking pictures.. I am not very mechanicaly inclined just trying to get my olds on the road..So if no one wants to help thats fine

jaunty75

Of course it is!!!

C'mon, man, I'm just joshing with you! I'd be more than happy to take some pictures and post them for you. It was a JOKE. That's why I put a smiley face!!

jaunty75

Here are four shots of the carburetor and surroundings on my '73 Custom Cruiser, which also has a 455. If you need something more, let me know.

jeffreyalman

man that thing is breathing it's own exhaust those years were so prehistoric by 75 it was like rockets again

jaunty75

There is a vacuum hose routing diagram (schematic, not a photo) on the lower left of page 6C-21 in the Chassis Service Manual. It is Figure 6C-26. I don't think it shows every hose under there, but it shows the connections to the distributor vacuum advance, EGR valve, EGR control valve, distributor thermal check and delay valve, thermal vacuum switch, and automatic transmission modulator vacuum hose.

There's also a diagram showing crankcase ventilation and air cleaner hose connections on page 6C-29, Figure 6C-41.

1973olds98

The 2 vacumm lines coming out of the front of the carb,,Where are they going..Also the tube coming from the transmission is that running off the manifold vacuum,,And the egr line is going to the vacumm port switch correct?

jaunty75

Here's two more photos.

The first one looks straight down at the front of the engine. Of the two smaller hoses coming off the front of the carburetor, the one on the passenger side is about 6 or inches long and attaches to the EGR control valve. Another hose comes off of the this and loops around under the steel coolant bypass hose to the driver's side of the engine where it attaches to the EGR valve itself. This can be seen in the second photo. The EGR control valve is not in the position shown in the figure in the service manual. That figure shows the EGR valve with a short piece of hose coming off of it to the EGR control valve, and then a long piece of hose looping around ABOVE the coolant hoses to the carburetor. I doubt the actual arrangement matters so long as the EGR control valve is between the EGR valve and the carburetor.

The smaller hose coming off the driver's side of the front of the carburetor is supposed to connect to a Distributor Thermal Check and Delay Valve (which appears to be missing in my car), the other end of which connects to the middle port on the thermal vacuum switch. The top port of the TVS goes to the distributor vacuum advance, and the bottom port of the TVS connects to a T-fitting, one side of which goes to that little blue/green square port coming up out of the manifold just to the right of the fuel filter housing in the photos. The other side of the T-fitting goes to the transmission vacuum advance. All of these are show in Figure 6C-26.

In looking at all of this more closely, I've discovered that my car isn't right, either. I've not done anything with the engine yet since I've had the car as I've been working on an array of other problems while getting the interior back in shape. But I've discovered that, for reasons unknown, the thermal vacuum switch has been completely bypassed. There's just a small hose connecting the top port to the bottom port with the middle port open to the atmosphere. The transmission vacuum modulator is connected to that blue-green, square port coming up out of the manifold just to the right of the fuel filter housing. That's as it should be, but it's supposed to be through that T-fitting mentioned above. I'll need to fix this.

greenslade

this may help good luck

jaunty75

Yours looks like mine. A direct connection from the manifold to the transmission vacuum modulator with no T-fitting going to the thermal vacuum switch. Is your TVS connected?

I see you have the same arrangement going to the EGR valve.

greenslade

greenslade

jaunty75

Can't really see a lot in the second photo because it's too close to the carb. Need to back up a bit so we can see where the hoses go.

Third photo is better. Thanks.

What about the thermal vacuum switch? It would be located just behind the oil fill tube in the third photo, so we can't see it here.


Here's one of my photos from above, but I've circled the TVS. You can see that the top port has been connected to the bottom port with the middle one open. I've no idea why it's this way. I plan to properly redo the hoses based on the service manual. Autozone has the TVS, although they call it a "ported vacuum switch," and it's $21.99.

greenslade

Found vacume hose tag in glove box it shows hose routed under thermostat housing as in jauntys pic.

1973olds98

I pretty much figured it out,,thanks guys

jeffreyalman

think I will unsubscribe to this one

1973olds98

here she is ready to be dropped in..

jaunty75

Looks very nice, but I have to ask. It seems like more things have been painted blue than were that color originally. Would, for example, the water pump, oil filler tube, and coolant bypass line (the short, downward-curved coolant line coming out by the thermostat) all have been painted engine color originally?

1973olds98

Ummmm,,,,..I am very happy with the way it came out...I hope it runs as good as it looks...I think the water pump should of been left the color that it came when i bought it....But i like the way it blends in with the block..I have no idea what the oil filler neck should of been...When it was stripped i know it had blue on it and alot of grease lol,,,,The thermostat part your talking about i dont know either..It was pretty nasty looking when i bead blasted..I guess I could of painted it black or something..You thin it would look better if the filler neck,,water pump and thermo housing was another olor..?

jensenracing77

i think the fill tube and water pump were engine color originally. i don't know about the bypass but think it was also.