NorCalSS

Being that its winter I have my Cutlass in the garage and I want to do some under hood cleaning and repairs. I picked up my Cutlass not long ago and its been parked in he garage while I tend to other items.

Its now time for her to get my attention. Im going to be checking/replacing/and re routing wires, hoses, and vacuum lines, full tune up and fluid changes along with giving the engine a good cleaning.

Anyways I was messing with it today and wanted to hook back up the heater. I have one hose coming from the core into the water pump, another hose coming out of the core is capped. The capped hose is supposed to go to the back of the engine area from what I have been reading on this site even pictures I seen on this site shows me where. I cannot find the place that a heater hose would go into.

Im trying to figure out what the previous owner has done to the car and why....FUN!

I attached a few pics to hopefully give you an idea of what I am talking about. Sorry for the big pics. Im picture posting illiterate .

Capped heater hose:

IMG_20120117_193421.jpg

Comes out and just hangs to the right :

IMG_20120117_193436.jpg

Hose should go somewhere around here right?

IMG_20120117_193747.jpg

Dirty engine bay shot. You can see the hose in question, I put it up on the carb for a better pic:

IMG_20120117_193616.jpg

Allan R

The problem is you've got a replacement intake manifold. The OEM manifold had a heater control valve at the back that the hose connected to. Its a functional part of the cooling system for cars equipped with AC. You should still have heat, but the main purpose of that valve was to cut off hot coolant going to the heater core when the AC is set on MAX. The valve operates on vacuum. When your AC is set to MAX, this sends a request for full vacuum to the heater control motor, shutting off the flow of coolant to the heater core. In various temp settings of AC the vacuum allows circulation so there is a blend of air to balance the temp you are selecting. When you are running in vent or heat modes, there is no vacuum in the line which restores full normal heating capability.

In MAX AC the reason for the valve was to prevent the supercooled air from competing against hot coolant flowing through the heater.

Take a look at the attached thumbnail. The heater control valve is directly behind the air cleaner. It has an offset where you can see the heater hose attached.

This is the actual valve. The threaded end goes to an intake manifold boss. The vacuum line attaches on the small nipple.

NorCalSS

the previous owner gave me the compressor and bracket to attach the compressor to the engine however even if i hook it up it wont work due to the non oem manifold correct? The bolts to hold the compressor bracket are still on the engine.

Looks like i need to track down a fan issue too. I never tried the heater until today and get no air moving through the vents. I have the service manuals online so i will pull up the heating section and search here for some answers.

A junkyard by me has a 70 and 75 delta 88 that they just got last week and what they say is a 69 olds 88/98. Would the Deltas make a good donor for a manifold on my 350. Also didnt all deltas of that era come with 455's? If so and if the engines look decent i might just pull them and use them for a swap into my cutlass.

Allan, thanks for your help. a lot of searching I have been doing your name is always there helping out. Newbs like me appreciate it. This is my first olds rocket I have messed with. Im usually wrenching on my LT1's.

Thanks again, Joe

Lady72nRob71

Heater fitting should be right around where the ground strap braid is going.
IMG_20120117_193747.jpg

You can get an idea of where it should be from this picture...



If you clean away all the crud back there I am hoping you will find a threaded plug or something.

NorCalSS

PERFECT! Thank you very much for those pics. When I get off work Ill put some degreaser to that area and see what I find.

The Engine runs OUTSTANDING but I want to clean it up a bit and have a tiny oil leak I need to fix

Lady72nRob71

Glad it helps...
Get a small wire brush in that area to remove the heavy deposits, then degrease. Those back sections often get lots of buildup over the years!

hookem horns

I also have an aftermarket intake with no vacuum control valve and it works fine with just an open nipple connected to the heater hose. AC is disconnected for now anyways. I would be careful that the heater hose was blocked off for a reason, like a bad heater core. Just want to warn you of the old can o' worms before you hook it up and coolant starts running into your passenger footwell.

NorCalSS

Yeah I figured it might be unhooked for a reason. Thats the bad part about picking up a car from someone that knew NOTHING about what was done to it which is why I am looking at and going through everything. I've had my carpet up for a bit taking care of interior items so im prepared for a water fall,lol. Thanks for the heads up.

Thanks again guys! I have very few posts because when I have an issue and search I always find the answer. Great site and the members are a great asset to use newbs, appreciate it.

Allan R

Dane,
I think his heater hose has coolant going to the heater core. There is a line from the water pump to the heater, and the one blocked off (for the heater control valve) suggests that the heater core is holding pressure ok. If its not leaking the problem he's got is no circulation. Make sense to you? The 'loop stops at the blocked hose.

Norcal, if you don't have heat don't worry about the compressor pump for now. If you need heat, find that coolant boss at the back of the manifold and hook up the 'heater to engine' hose. It should be there even on an aftermarket manifold. Probably has a plug in the boss. 2 things you can do:
1. You can replace it with a threaded straight connector if you don't intend to install the compressor for now. At least it will give you some heat in the car.
2. You can install a heater control valve and just plug the vacuum line for now. When you get the compressor installed and the system charged, you will need to make sure your vacuum lines are properly hooked up and don't leak. If it was me? I'd use option 1 for the quick fix.

re: no fan speed? Not on ANY of the low,med or high? Check the back of the dash plate to see if the electrical connection to the fan switch has been pulled off. That would be my first check. It's not too likely that all speeds go at once. The motor could be shot or unplugged too? If you need to change it, that involves dropping out the PS inner fender liner. I always start with the easy things that most often get overlooked.

hookem horns

Allan is right, I did not notice the other hose connected to the heater. Good sign that the core is OK and all you have to do is hook up the hose to the manifold.

Spend some time with a volt meter or test light on the fan circuit to narrow down where the problem lies. Might just be a bad connection or ground somewhere with all that "patina" under the hood. There are several threads on heater fan issues if you search.

70Post

Norcal - Can't really tell from your pics as they aren't too clear BUT...your intake MAY have a cast-in boss or pad that sticks up and is flat on top. This would be right over the spot where the water passage is on your cylinder head (under the intake of course). The intent there would have been for the owner to drill and tap the cast-in boss or pad and install whatever fitting was needed for a heater hose or a heater control valve.

OR...the hole may already be there but close off with a screwed in plug.

NorCalSS

Sorry guys no update as of yet. Was my Bday on the 18th and have been busy with other things, kids, wife, yadda, yadda!.

I did get a chance to use some degreaser in the area and so far have seen no plug. Im going to spend some time on it after work today and completely clean the area and get some better pics up. I used my phone for the first pics so they are not too great.

FAN Issues; thanks for the input on this issue. I will also tackle some of this on the weekend. I have searched for the fan issue and have lots of info printed out to assist me + I have all the manuals needed to tackle anything, thanks to the Wild About Cars Site.

Ill keep you posted and thanks again!

Joe

Lady72nRob71

We know 'yadda' = 'beer'!
Hope you had a great one!

hookem horns

Joe,

Can't tell what intake you have, but if it is a 350 EBrock Performer I can send a pic of how/where my heater hose connects.

Allan R

Happy belated birthday Joe! Amazing how it turns out to be the day you want to enjoy and relax, but you end up as busy as a taxidermist during hunting season!

Mak

I had the same problem... edelbrock intake, no heater valve, heater code bypassed. After I replaced the heater core I ran the heater inlet hose directly off a nipple at the back of
the manifold with a 45* elbow. The heater valve also acts as a restrictor, so there was too much flow without... I could hear the coolant flowing the heater core and it would make
a moaning sound on acceleration. I found an inline restrictor at the parts house and added to the inlet hose (you can see it in the pic)... works great now. With the heater door open gives plenty of heat... with it closed the heater box is still a little warm to the touch, but no noticeable heat on the floor.

Allan R

One thing I really like about your engine compartment is how easy it is to access the heater fan.

Mak

Yeah, it's right there in the open.
The heater core replacement wasn't too bad either... not nearly as bad as I expected.

NorCalSS

Thanks for the belated bday!

Quick update. heater fan does work. I never tried it before until recently. As with any repair start with the simplest repair,,,in this case it was a missing fuse. Fan works great, little squeeky but all speeds work. It does not switch from defrost, heat, etc, just a constant flow from the lower heater vent. Going to check vac lines and connections to figure it out.

cleaned the area where the heater valve is supposed to be and guess what...........ITS WELDED UP! I can assume that is why the fuse was gone.

I dont care about AC and am going to pull everything that has to do with the AC, but I do need heat! What are my options?

1. Pull manifold and drill and tap welded area for a heater valve
2. pull manifold and find another one either in the junkyard or new?
3. Anyone have a used manifold and want to trade for all my AC parts?
4. Or ???????

Im not in a rush to drive it till the summer so I can take my time.

Thanks again, Joe

Allan R

A fuse? That was easy! Now about the squeaky fan....put out some cheese or peanut butter to catch the mouse running around in it!! Seriously, if it's squeaking run it on high or med for a few minutes. There might be some light corrosion on the bearings. If it still squeaks on low speed, the bearings are starting to go and you should think about replacing it.

Bugger on the welded up boss. By the time you take this out, get it drilled and tapped, you could just put on another one. Look for a good used one, or like you said, check out the local boneyards for one. Prices there are dirt cheap.

If you're going to bypass the AC, just put in a straight fitting to the boss on the intake and run the heater hose to it. Plug the vacuum line coming to it. The AC vacuum lines are likely what's causing you trouble with the selection from floor to defrost etc. Check for brittle, cracked, missing or open disconnects. You might have to take the lower kickpanel on the r.s. off to check the dashpot there.

FYI, there are always guys here looking for good AC parts.

A72Cut

I have to remove my OEM A/C but would still like to have a heater. What type of heater control valve should I use to replace the OEM unit?

Lady72nRob71

IF you retained the AC control panel, you can just install a standard AC heater control valve. They are still available - Rockauto has them.
If you changed to a heater only control panel, then you do not need a valve. The AC control panel has the vacuum hose that runs to the valve.

A72Cut

I have removed the vacuum "ball" as well, and do have the a/c panel still in place. I have a new HCV but of course, it's for an a/c car so it has the threaded port on the back for the sensor.

I can still use that? And what might be a good vacuum source?