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New user here, so hello everyone. I've never owned an Oldsmobile before. And I've never owned a car this old. I've never even had a carbureted vehicle, aside from a motorcycle I built and an ATV. Oldest car iv owned was a 1988 Mercury grand Marquis and I loved it. I'm an experienced mechanic and familiar with restoration and most mechanical work. Just so you know a bit about me.
I've been drooling over this 71 ninety eight for about 3 years. Finnaly managed to hunt down the owner. Long story short, he put this car in the warehouse in 1989 and it never left. He used to go crank it up once a year but after a while that stopped. It hasn't been cranked up for about 10 years. Was sitting on 4 flats... Tired look great and even still have the nipples in between the tread... But with their age I doubt they're safe. So I own this now!
Again I've never had a vehicle thisbold. Never worked on carbureted car.. aslo never had an olds...
Planning to,
Drop and clean the tank
Drain fuel lines
Replace fuel filter
Drain and replace oil
Drainand replace coolant
remove spark plugs
Add a bit of oil to each cylinder
Crank it over by hand
......
Fire it up?
Am I missing anything? Is there any knowledge that those of you with more experience with these cars would like to give me?
Anything I should know about the 71 ninety eight?
Anything interesting or cool to know?
"Anything I should know about the 71 Ninety Eight?" You asked? Yes, just one important thing. Stop calling it a "Delta Ninety Eight" The car is a Ninety Eight. A Delta Eighty Eight is a totally different car. I cringe everytime I hear someone say they have a "Delta Ninety Eight" No such car. Otherwise, we love your Ninety Eight and welcome to the group friend.
Shawn, that's an AWESOME car. 71 98s are the best, if I do say so myself!
If an 88 Grand Marquis is the oldest and biggest car you've driven you're in for a treat when you get it running. 71-76 C body cars were the biggest GM ever made. The only Oldsmobile bigger than a 98 would be a Custom Cruiser. They call them land yachts for a reason!
Hail to the new boat captain. I'd also change the rubber line to the fuel pump. Be careful with fuel filter its in the carb inlet, very easy to strip the threads. Also check under the distributor cap for critters and check points gap.
Welcome to the group... Nice find... I would recommend changing all the vacuum lines as well as the fuel lines... Chances are there will be some vacuum leaks after all the years it has been dormant...
Drop and clean the tank
Drain fuel lines
Replace fuel filter
Drain and replace oil
Drainand replace coolant
remove spark plugs
Add a bit of oil to each cylinder
Crank it over by hand
......
Fire it up?
Am I missing anything? Is there any knowledge that those of you with more experience with these cars would like to give me?
Anything I should know about the 71 ninety eight?
Anything interesting or cool to know?
I recently put a '78 Toronado back on the road that hadn't been started or driven in 13 years.
I wouldn't necessarily assume you need to drain and clean the fuel tank or drain fuel lines. I found that the gas that remained in the tank of my '78 was not solidified or jelly-like or whatever, and, when mixed with some fresh gas, worked just fine. I ran the engine, and this is by far the easiest way to clear the old gas out of the system. Dilute it with new gas and burn it through the engine. Now, if you have some OTHER reason to drop the tank, such as the tank itself is leaking and needs to be repaired or replaced, or the fuel gauge sending unit needs to be serviced or replaced, then you'll have to drop the tank, anyway, and you might as well discard any old gas and clean it out while it's off the car. I've dropped tanks on two cars, and it's never a pleasant task, so I try to avoid doing it unnecessarily.
None of the tasks you mention above concerns the brakes. If you're planning to do more than just start it and want to actually drive it around, you want to check all aspects of the brakes. I ended up changing everything on my car (new power booster, new master cylinder, new proportioning valve, all new hardware, drums, and wheel cylinders in the rear, new calipers, rotors, and pads in the front, and new rubber brake hoses wherever they existed). The only parts of the brake system I didn't replace were the steel lines.
Drain and replace the transmission fluid.
As noted above, replace all RUBBER parts of the fuel system. There'll be rubber lines between the tank and the hard lines and then between the hard lines and the fuel pump. Check all the vacuum hoses under the hood as they can harden and no longer seal at their connection points. Vacuum leaks can cause all sorts of engine running problems, and they're easily fixed.
As far as interesting things about the '71 Ninety-Eight, it was the first year of that generation of full-size (B and C body - 88 and 98) Oldsmobiles, and that generation lasted through 1976. It was the year of the incorporation of "flow-through" ventilation on all GM cars, so you'll see little louvers in the trunk lid. Those were 1971 only as, in later years, Olds put those louvers in the rear door jambs. Flow-through ventilation also means that the heater/AC fan is ALWAYS on, even when the system is set to OFF. This was designed to keep fresh air coming into the car at all times. We've had new owners of other "flow-through ventilation" cars come on here and ask why they can't turn the fan off. This is why.
The '71 through '76 full-size Oldsmobiles represented the longest of these cars ever produced by Olds as the next generation, which began with the '77 models, was downsized. The 1970 Ninety-Eight had a 126 inch wheelbase, was 225.2 inches long, and weighed anywhere from 4400 to 4900 lbs, depending on body style. The '71 Ninety-Eight had a 127 inch wheelbase, was 226.1 inches long, and weighed anywhere from about 4500 to about 4600 lbs, depending on body style.
1971 was the first year in forever that the 98 was NOT available as a convertible.
1971 saw a full-size station wagon in the Oldsmobile line-up for the first time since 1964. It was called the Custom Cruiser, and it was based on the 98 wheelbase.
The one and only engine you could buy in any '71 to '76 98 was the 455 with a 4-bbl carburetor. For 1971, it was rated at 320 hp
The '71 to '76 88s and 98s were the last generation of full-size Oldsmobiles where you could buy a four-door hardtop body style, which is what your car is. We can't tell from the photos, but your car is either simply a "Ninety-Eight Sedan" or a "Ninety-Eight Luxury Sedan" in Oldsmobile parlance. The base price of the Sedan was $4853 while the base price of the Luxury Sedan was $5159. The latter was the heaviest and most expensive of the four 98 styles that year. There were far more Luxury Sedans built (45,055) than Sedans (15,025), so, in spite of the higher price, buyers preferred the Luxury Sedan by a ratio of 3 to 1. If you don't know if your car is a Sedan or a Luxury Sedan, let us know the VIN as I think that will tell us.
You're joining an interesting group of Oldsmobile collectors. By far the most popular are the A-body Cutlasses and 442s, but there are those of us who prefer the big cars. During my time in the hobby, I've owned a '64 Jetstar 88, '67 and '75 Delta 88s, a '73 Custom Cruiser, and a '78 Toronado. I don't think most people would consider the Toro a "full-size" Oldsmobile in the traditional sense as that term is usually reserved for the 88s and 98s, but it's not a small car and actually was the largest Oldsmobile produced for the '77 and '78 model years as the Toro didn't get downsized until 1979.
Good luck with the car, we want to see a LOT more photos, and keep us apprised of your progress.
Last edited by jaunty75; February 28th, 2019 at 02:33 PM.
Wow I wasn't expecting so many great responses. I've been on other car sites and never found the enthusiasm that you guys seem to have. Well I'm happy to be a member of the boat in community!
I did forget to mention brake lines but I was planning to change all the rubber stuff on the car. I did manage to get it to fire up for a second yesterday, but again I've never worked on a carbureted car. Wasn't really sure what I was doing.
After some research I did find that you need to pump the gas pedal to prime It.. well my gas pedal is completely loose. The cable is there and it seems to still have the nipple on the end. Not sure why it's so loose, there's no way it's stretched this mcuh. There was a broken spring on the carb also. I'm guessing it was attached to the throttle cable in some way. So I've got to figure that out first I think.
Also there are a few vacuum lines I need to find out where they go. I can take some pictures later, but there one like coming from the front of the carb that has a bolt in it... One coming out of the top of the engine on the front side that has a bolt in it, and another from the top of the engine behind the carb that also has a bolt in it lol. I really didn't think the car had been messed with much but obviously someone was under the hood at some point.
I'll snap some more pictures later today. Thanks everyone!
Lots of good advice from you guys and I appreciate it. I promise to stop calling it a Delta LOL.... haven't really gone into the gas tank yet, was going to hook up a fuel tank directly to the carburetor to get the engine running and then go from there with the rest. I'll definitely have a sniff at the gas as well
Does anyone have a link to any website where I might find diagrams and stuff like that? Been looking for a service manual just to have but haven't found one ywt
This is the "go to" place for info on you Olds. A FSM and Chassis manual are must haves if you plan to do your own work. If you take a pic of the carb and the disconnected vacuum lines I'm sure someone can tell you where the vacuum lines go.
I'll hazard a guess as to why those vacuum lines had bolts shoved in them: previous owner knew he had leaks, and was only interested in being able to start the car every so often to keep the oil circulated. Wonder how long those ashtrays have had ol' butts in them. Dump those out ASAP so that you can start getting rid of that stale smell.
Holy cow - a 98 with no options (other than air conditioning and the fancy wheel covers). I didn't expect to see window cranks and a seat adjuster ****.
Hey thanks for the info. I'll be getting a manual asap. I got the engine running today and it purred like a kitten..... However.... I have problems...
Before cranking it up, I replaced the fuel filter. This one is inside a housing that just screws into the front of the carb. Well when it was rubning, I noticed fuel dripping out of there pretty rapidly... It was also cockeyed... Took me to back out, and of course it's all stripped out in there... Sigh... So it looks like that's all one solid piece of the carburetor body. Do I need to budget for a new carburetor now before I can go any further? I planned to have it rebuilt but I'm not sure if that's an option now that those threads are stripped out.
And thanks for all the replies. It's really great to have a place to come where all the knowledgeable minds hang out lol.
A good carb man can put a heil-coil in it it for you. Here's the part. Replaces the inlet threads. This one has been discontinued, but you get the idea. Good luck with it it. I will be following along.
Okay, so I changed....
oil
Oil filter
Fuel filter
Air filter
Brake hoses
Brake pads
Rotors
Brake master cylinder
Spark plugs
Plug wires
a few old vacuum lines
The car does not want to start when it is cold. Can barely get it to turn over. I used 10w30 for the oil. Once it is running, it acts like it's sucking air somewhere. If I'm sitting at a stop light it has died on its own once or twice. But if it doesn't die while sitting, then I really have to feather the gas pedal or it will die. Cranks right back up. I took it on the freeway and I noticed that when I try to really open up the throttle it just bogs down and starts to die. If I baby it, it makes it to about 70mph, but if I try to give it a little more gas to get past 70 it bogs down really bad.
From my experience working on a carbureted bike, im guessing the fuel air ratio is off. I'm guessing that either my carb needs cleaned and is not getting the right amount of fuel to the engine, or, I am sucking a lot if air somewhere throwing off the mixture.
I'm going to add some pictures here for some of the plugged vacuum lines.
There's a broken sensor of some kind I'm hoping you all will identify for me.
There is like a "tree"? Coming from the engine with 3 nipples on it. I'm assuming 3 vacuum lines need to be attached and go somewhere. I wasn't sure what it is yet so I put a 2in line with a bolt in it on each one just to plug it for now.
There is a bigger vacuum line coming from the top of the engine behind the carburetor. It goes to a canister on the firewall. It's extremely dry rotted. Was going to replace it, but it goes into this odd connector where one piece goes to the canister and a smaller line comes out and goes into the firewall.
So any help or info you all can provide would be greatly appreciated. Thanks again
It sounds like you have all kinds of vacuum leaks, and low vacuum will make the engine run poorly. That thing with three ports on it some kind of a vacuum switch that opens something when the engine temperature reaches a preset value. There should be a source of vacuum connected to one of them while the other two are connected to things that need vacuum to operate. I apologize for the general-ness of this, and I'm sure others will know better about that switch. What you REALLY NEED is a chassis service manual for this car, and you need to pore over it to find all the vacuum diagrams and get everything hooked back together properly. Unfortunately, the manuals do not have a single, all-encompassing vacuum hose diagram. Each component, such as the brakes, HVAC, EGR, PCV, evaporative emissions, cruise control, brakes, etc. has it's own vacuum diagram in its own part of the manual. You'll need to look through them all.
That canister on the firewall is the heart of the vacuum control on your heating/cooling system. Can you get the air flow out of whatever vents you want (floor, dash, defroster) by setting the lever, or does the air come out the floor vent no matter what the the lever setting is? Without vacuum, the vent doors don't move. That canister is a vacuum reservoir, and, yes, there is one hose coming from a vacuum source on the engine going to the canister and another that connects to the canister and disappears into the firewall. That hose is connected to the HVAC control head and directs vacuum depending on the setting of the A-C/heat controls.
As I say, get a manual and get those hoses properly connected and with modern rubber. Low vacuum will cause engine running problems, and my guess is that you have low vacuum.
One thing you should do is get a vacuum gauge and connect it to a vacuum port on the engine and see what your reading is. You can tell a great deal about engine problems by the way the vacuum gauge behaves.
Last edited by jaunty75; March 5th, 2019 at 12:33 PM.
Thanks for the reply jaunty. I went ahead and ordered the chassis service manual last night. Actually I found one for a good price that also included a Haynes manual and a sales brochure from 71. I'll keep you all updated
The only vacuum lines you need for the car to run properly are the manifold vacuum hose going to the brake booster, transmission and distributor. The air doors in your HVAC system won't work but if you eliminated all of the other vacuum hoses hopefully you could get rid of the vacuum leak.
Well I bought a bunch of vacuum lines and connectors yesterday. It was 13 degrees outside and windy so I didn't mess with it. Already spent 3 days with my toes and butt numb while I was working on this hahahaha. Today is in the 20's so I'll get on the vacuum lines and give you guys an update. If it doesn't work today I suppose I'll need to wait for the service manual to be delivered
Keep in mind that the various hoses are different diameters. The brake booster hose is one of the largest, and I think the PCV valve line is one of the bigger ones, too. The charcoal canister on my '78 Toro takes three lines, each a different inside diameter. The HVAC vent door line, EGR valve line, and transmission modulator line are among the smaller ones.
Yeah I chopped off a few inches off of each different size line to take to the parts store. Got 5 ft of each. Forgot to get one for the break booster but doing that today too. I did change all of the vacuum lines this morning that I had with me. Cranked up nicely and idled well, but still bogs down and stalls when driving. I'm going to replace the brake booster hose today also, but the only other 3 lines I'm seeing... One is the one coming from the front of the carburetor that has a bolt in it, and one coming from the manifold behind the carburetor that also has a bolt, and the last is on the back of the carb at the top. I included pics. If anyone has any idea where these go, id appreciate it. Going to get a vacuum guage soon also to get more info and chassis manual won't be here for a few more days Back og the carb. One plugged vacuum line from top of carb and one from intake manifold blocked as well One plugged vacuum line below and to the right of fuel line input.
As I recall, there was no EGR on my 71 98 when I bought it. I did have the vacuum control switch though...
To be honest, I'm not sure there was an EGR system in 1971. My source was for somewhat later engines. EGR probably came later than 1971. I don't know what that ported vacuum port shown in the one photo is supposed to connect to.
Well, before I messed with it, the line going to the distributor and the one going to the transmission we're just connected to a T that went into the top of the manifold. I plugged that line off and ran the lines exactly like you said to that valve. I didn't find an EGR. Also the top of that valve kind of looks like it has another nipple. It's on the top and recessed a little. May just be part of the housing but thought I'd mention it.
So now every single vacuum line has been replaced. She still doesn't like to start. Sometimes I go to crank it up and it turns and turns and if I keep messing with the pedal it will run, but extremely rough. Then it dies if I stop giving it throttle. Other times I expect it to give me trouble and it will start in half a turn and run smooth as can be.
I'm guessing I'm gonna have to just end up biting the bullet and taking the carb off and ordering the kit and cleaning/rebuilding it.
I haven't messed with any of the adjuster screws yet either because it does seem to idle smoothly when it does turn on... But actually driving is a different story
When you get the air cleaner off (probably is off now) check and see when carb is pumped if two streams of fuel spray into the carb. Sounds like your accelerator pump may have gone bad, common problem with any car of that age sitting for that length of time with alcohol based fuel in it..... Lost in the fifties.... Tedd
Did you set the choke? IF the choke isn't set properly it will be difficult to start.
You also need to disconnect the vacuum at the distributor and set the dwell and timing.
Well the only thing I have been told I need to do to set the choke, was to hold the gas pedal down for a moment then release. Seemed like there should be more to it than that but I suppose I should maybe Google it lol.
As far as the accelerator pump, I did look in there and as soon as I touch the throttle, I do get 2 good streams of gas coming through.
The distributor vacuum control switch has a plug on the top of it that broke. So I'm going to rig it up to at least get the wires connected to it but I will eventually replace it.
Today I sprayed a good deal of carb cleaner into the bowls today hoping that would help. Seems to run smoother but still bogs down.
One thing I haven't done is set the point. Honestly not sure how, it's the next thing I need to research. I've had a few cars that have distributors, but usually just change the cap and rotor. I don't even know if they had points? But perhaps that is the issue... I'll keep working at it though and keep you all posyed.
Again I really appreciate all the help you you all have given.
Well the only thing I have been told I need to do to set the choke, was to hold the gas pedal down for a moment then release. Seemed like there should be more to it than that but I suppose I should maybe Google it lol.
Or you could read the owner's manual. What you've been told is correct. To set the choke on these cars, assuming everything is properly hooked up and adjusted, you press the gas pedal all the way to the floor, then release it, then turn the key. Pressing the pedal to the floor closes the choke flap (or whatever it's called) and puts a squirt of gas into the cylinders. The closed flap causes the engine to run rich, which is what you want with a cold engine. The coil in the choke housing (that black round thing on the side of the carburetor) is attached to the choke flap and slowly unwinds as the engine warms and opens the flap to allow more air in. A warm engine doesn't need to run rich, and the flap opening leans it out.
For a warm engine, the starting procedure is simple. Hold the gas pedal down about half-way and turn the key. If the engine ever won't start the regular way because it's flooded, you hold the pedal on the floor while turning the key. It gives the engine one more squirt of gas, which it doesn't need, but holding the pedal to the floor opens the throttle and lets as much air in as possible to help burn off the excess fuel.
Originally Posted by Shawnk111
Today I sprayed a good deal of carb cleaner into the bowls today hoping that would help. Seems to run smoother but still bogs down.
I would rebuild the carburetor. It's not difficult. I've done it a couple of times myself. Kits are only about $20, and there are excellent videos on youtube to guide you through it step by step. I used this one, which was very helpful. Have a laptop computer beside you on the bench showing the video, and you can pause it as you go along.
I found this video very helpful. You get a nice, satisfied feeling when you put that nice, clean, refurbished carb back on the engine.
One thing I haven't done is set the point. Honestly not sure how, it's the next thing I need to research. I've had a few cars that have distributors, but usually just change the cap and rotor. I don't even know if they had points?
If the ignition system is original, it has points (not "point," singular, but "points," plural). Electronic ignition was introduced a few years later. You probably should replace the points and condenser along with the rotor and cap, and then set the gap, dwell angle, and timing. The chassis service manual will have the specifications. You'll need a tachometer, dwell angle meter, and a timing light, but you can often buy a combined tachometer and dwell angle meter.
Alternatively, you can replace the points and condenser in your existing distributor with a kit to convert it to electronic ignition. It's not difficult, especially if you're going to replace the cap and rotor, anyway, and then you'll never have to worry about the points and condenser again as they are replaced by solid state electronics. Just set the timing and you're done. I did this conversion on both my '67 Delta 88 and a '73 Custom Cruiser I once owned. No problems.
This is the distributor vacuum control switch. When the engine gets hot the switch will switch the distributor vacuum from ported to direct and bring up the rpm’s. Reference your manual. But I believe the middle nipple goes to the distributor bottom goes to manifold vacuum and the top to ported vacuum on the front of the carburetor. You should also Re-torque the carburetor attachment bolts to 15 ft/lb. I’ve seen these carbs leak from the base gasket before. You can spray starter fluid around the base while the engine is at idle and see if the rpm’s go up. If it does, that’s where your vacuum leak is. Good luck!
To be honest, I'm not sure there was an EGR system in 1971. My source was for somewhat later engines. EGR probably came later than 1971. I don't know what that ported vacuum port shown in the one photo is supposed to connect to.
February 28th, 2019, 05:47 AM
