When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
So I acquired a beautiful 79 cutlass supreme Diesel.
Haha. Sometime in its life it was nicely swapped with a gas motor. I am told its a 455.
They left the original brake system in place, only I am less a master cylinder. Buying a master cylinder and booster package would be best. Yet do I buy single diaphragm or double?
The exhaust pipe is directly under the oil filter. Move the pipe or relocate the filter?
Should I remove the air conditioning or rebuild it next spring?
Is there a way to identify the rear axle?
I think the the motor mounts need to be replaced.
What causes an engine to lock up?
Could I, should I, just give it some starting fluid and go for it? The engine has a Quadra jet, clutch fan and a alternator larger than the one on my 360ci truck.
Assistance, advise and opinions welcome. Thank you for your time.
Austin
Last edited by 4x4Buzzard; Aug 17, 2020 at 06:21 PM.
I'm pretty sure the motor is a 403, not a 455. If you look at the picture of the motor mount you posted you can see the numbers 403 cast into the side of the block. There should be a ledge between the water pump and intake manifold that has the actual block casting numbers on it. Will be probably be 557265 or 554990. See my photo for example. If it was mine, I'd redo the entire exhaust system and move the pipe away from the oil filter. No need to relocate the filter. I'm not sure where you live but I'd keep the A/C and have it serviced, especially if you're in a state where the summers are very hot. Your rear axle is (probably) the stock 7.5 inch one that originally came with the car. The only ratio available with the 260 diesel and automatic trans was the 2.41. There is a code stamped into the axle tube, on the top passenger side somewhere in the middle of the tube, that will tell you the ratio. That's assuming it hasn't been changed by a previous owner. As for brakes, I'd stick with the stock master cylinder that was originally used in the car. The stock braking system was more than sufficient for everyday use with these cars.
It looks like the car has sat for a long time without use. I'd be hesitant to try to start it without going thru some steps to ensure it won't have some serious problems later. There have been numerous discussions on this site about it so I won't go into it. Just search for it.
The 403 V8 is a nice motor. They used these in a lot of the full-sized cars from 1977-79 along with the Trans Ams.
If it was mine I'd do the following things to it once it was cleaned up and running properly:
- rebuild the Q-jet carb
- replace the intake with an Edelbrock performer
- complete true dual exhaust
- mild shift kit in the transmission
- add a posi and change the gears to 2.73, 2.93, or 3.08
No need to go too wild with the gearing unless you're planning on using it for drag racing. Oldsmobiles make great low-end torque so there's no need to wind the engine up too high.
Good luck with your project
Sorry, forgot to add the photo.
This is a picture of the Olds 350 V8 in my 1979 Hurst/Olds. You can see the casting number 395558 underneath the fuel line.
As for the brake system, your car is currently equipped with the hydro-boost system and only missing the master cylinder and possibly the vacuum pump, which is not shown in the photos... If the pump is still on the engine, you will only need the master cylinder for the hydro boost system... The other option would be to change the hydro boost unit for a vacuum unit...
Well being a gas motor now ill switch over to vacuum brakes.
Block number is 557265 4B
Also I think the motor is leaning to the passenger side.
May have to rebuild the carb before I try turning it over. Looks like some moisture got on the engine.
Those Cutlasses can make for good reliable cars but. I would definitely go over things like wants, needs, goals, extensively. How familiar are you with Olds....
Your car with its born in power-train is considered exceedingly weak. Diesel 260 V8, early THM200 and a 7.5 rear... Someone did you a huge favor swapping in that 403 if its nice and healthy. However the 7.5 is a terrible match for it and if the transmission is still a factory THM200, its a disaster waiting to happen. 403s were full size car and up engines for Oldsmobile. The base 403 is rated 185 HP and 320 LB FT, vs the 260 diesels, 90 HP and 160 LB FT.
So as you can see a 403 doubles power on both ends. True dual exhaust will push that difference even harder.
Would it be in the vin?
where is it marked on the Trans.
I got the car for free,, paid 200 to drag it home and the plan is the get it running. My truck is getting worn out and he doesn't get good gas mileage either.
If that's the case, you are set. A TH350 in good working order is a perfect pairing with a 403 particularly in a mid size car.
With regards to getting it running, whatever you do, put a soda bottle cap full of oil in each spark-plug opening before you attempt to turn engine over. I would likely turn the engine over by hand slowly but surely rather than cranking to begin with.
So the carb was frozen and so I took it off. Came off easy. I don't like what I see underneath.
Is the engine save-able?
I am going to vacuum out what I can.
That is a LOT of crusty rust inside the intake manifold. If it were mine, I would pull the valve covers and the intake. You can get gasket sets for cheap on ebay and Amazon. There are three major options for the intake. Soak the whole thing in Evapo Rust for a few days, use a wire brush in a drill to clean everything out, or straight-up replace it. Looks like you will be needing a new EGR valve too. You don't really want all that rusty scale going through the engine while it is running. If/when you remove the intake manifold you will probably find some crusty dried oil sludge in the lifter valley of the block and that can be vacuumed out fairly easy but if you are doing any kind of reliability refresh, it is a worthwhile MAW (might as well). Also, if the crank will turn, try turning it bacwards and forwards with the distributor cap off to find how much slack is in the timing set. If the engine is still factory original, the timing gear on the cam has synthetic teeth on it that WILL deteriorate and ultimately fall apart. Again, not an expensive repair but well worth the time and money if you are going to refresh the engine. The MAW's have you... Welcome aboard!
403 with a TH350, that's a nice combo. I blew up my TH200 by installing a 3:08 posi in my blue Caliis many years ago. I instead opted for a 200R4 trans to mate up with that axle. I still have a 260 motor but that was rebuilt and it runs so well for now it stays.
Best of luck with this project. But also, be sure to check the rear frame rails from the tires back to the bumper. If they are rusted/rotted out this is an extremely expensive fix if you can even find someone who will do that work. This is a big time issue with these cars.
From the pics, it appears that engine has had water leaked into it for quite some time. I really doubt that engine would ever turn over and would never run without a complete overhaul. Your best bet is to pull that engine and either replace it with a known good engine or have this one rebuilt.
From the pics, it appears that engine has had water leaked into it for quite some time. I really doubt that engine would ever turn over and would never run without a complete overhaul. Your best bet is to pull that engine and either replace it with a known good engine or have this one rebuilt.
What he said.^^ If mine I would get a bore scope and check each hole first for issues (rust) before I spent a dime on anything else. You could be looking down the hole of a coal mine. Might be cheaper to put the money into your other ride..... Just my thoughts....Tedd
Second, there's a reason that car was free. I am not saying abandon it, but, understand it may not go without more money, BUT, to scrap it will be the same assembled, or disassembled, and you can learn a lot on this car even if it is a dud. So, learn, put time and work into it, but be sure to not put money into it before you are sure it is saveable. It could well be that the engine is frozen, but maybe just needs a hone and some new rings. Or, even a real rebuild is not too awful if you do all the work except the machining. Engine ----> trans ----> rear end in getting it going.
I am not trying to be a smart *** but I've been down this road before, as I'm sure many others have. Sometimes someone can give you something and it still is a bad deal!! I would have to assume that the rest of that engine looks like what you discovered under the carb. Run, Forrest, Run!! Actually if you want to learn about cars and their workings, etc, take it apart and gain knowledge.
I agree with Roger, as much as it pains me to state this, I think IMHO this car is beyond rescuing per the photos. Motor, Trans, possibly the frame, all point to bad things around the corner. If you are looking for a good example of one of these cars, I know of a great one (a blue 1979 Calais with rare white interior and the chevy H 305 motor) for sale in Hartford, CT, I would buy it but my stable is full. Best to get something ready made and ready to go NOW then to sink tons of dough on something unknown.
Before sinking a dime in it, look over the frame rails in the back. I live in the rust belt, it was common to see 4x4 posts bolted to home made bumper brackets because the original bumper rusted and fell off. If the frame is rusty, it’s going to be expensive to fix.
Remove the oil filter, cut it open. Use tin snips, not a hacksaw. Pull open the pleats in the filter media. If you see metallic crud, you can be sure of mechanical issues.
If the filter checks out, pull the plugs. Look down the plug hole. Hopefully you don’t find the same rusty crap in the cylinders. If that checks out, pour a little oil down each plug hole.
If everything is going well so far, try and turn the crank. A breaker bar and 1 1/8 inch socket will fit the bolt on the harmonic balancer. Slowly turn the engine, hopefully you don’t find any tight spots where the engine won’t turn anymore, or turns with excessive effort. That means rust has formed, the piston rings are getting hung up on the rust. You might be able to wok the engine back and forth assuming the rust isn’t sever. Judging from the intake, I’m expecting the worst.
If against my predictions everything checks out, go buy a lottery ticket before your luck changes!! 😎
With winning lottery ticket in hand, either borrow or rent a compression gauge. If each cylinder reads fairly even, buy another ticket. If the readings are low but even, that’s a classic symptom of bad timing chain.
At this point, I’d try to start it, just to see what you have to work with. Try to crank the engine, check to see if you have spark. If not, time to look at the distributor and ignition system. Once that’s good, it’s time to try and start it. Either clean the old plugs, or install new ones. Make sure the float bowl of the carb is full of fresh fuel. Hopefully it starts. It’s going to smoke for awhile until the oil you pours into the engine burns off. Hopefully it doesn’t knock, rattle, fog the neighborhood, etc. once your sure you have a decent engine, then it’s time to check the transmission, fix the brakes, etc.
