Engine, Fix or Dump?

[MarkV]

So as you guys recall my 77 seville had the bad camshaft. Everyone wants a grand to 1400 to fix. The compression was good and it doesn't overheat or leak. However, I am thinking at this point it would be best to replace. I can buy a replacement with a 5 year warranty out of a 79 to 85 Eldorado for about 650 to 750 with free shipping and a 500 dollar install. The Eldorado uses the same engine it just requires the pan, pickup, oil filter and the old exhaust manifold from the old engine to make it work. What do you guys think?

[poci1957]

Others can weigh in but that swap sounds like a good deal to me EXCEPT if it were me I would consider if the exisiting engine had any recent valuable work done that the replacement might require later.  

 

If you go with the replacement I would suggest replacing seals and gaskets where possible while the engine is out--right now you can get them at Rock Auto for half what you will pay at the parts store and it is much easier to do out of the car.  Good luck, Todd C   

[MarkV]

The engine hasn't been opened up. Only injectors replaced, none of the other parts have been done

[C Carl]

I can't remember the saying. Something like the devil you do know versus the one you don't know. Fix yours. The shop should run in the camshaft properly, and for the rest of the engines life use the best fully synthetic oil possible. With that flat tappet engine, you should have a sufficient amount of ZDDP in the oil. Amsoil has such an oil formulated for these older engines. Use their Z-Rod 10W/30. I have no connection with Amsoil whatsoever other than as a consumer. If anyone can prove there is a better oil,  I will switch to it at the next change. Good luck. You will still be ahead with your purchase of this low mileage car.   

         -  Cadillac Carl 

[Bloo]

I would shove a cam in it. Best of luck whatever you do.

[C Carl]

Oh, also. : ANYONE WHO TELLS YOU THAT A '79 -' 85 ELDO MILL CAN BE TRANSPLANTED INTO A '77 SEVILLE HAS HIS HEAD JAMMED UP HIS EXHAUST PIPE AND HAS BEEN BREATHING FUMES TOO LONG.     -  CC 

[MarkV]

It's a 350 too right?

[poci1957]

Well, Carl may have an important point, since the Eldorado is front wheel drive and a later generation car the castings and mountings may be different, better carefully research first.   

[C Carl]

'79 Eldo is a 350, and although front wheel drive, could work? '80 Is 368 (perhaps '81 also, but after that the engines are the miserable HT4100), and with the right money could run, but I would advise you to stick as close to stock as possible. The closest to stock is the engine it came with. And it is a low miles mill which will serve you best. Unless you are going bass fishing, stay away from cans of worms. If you really want to throw away your good  engine and pump a lot of money into your engine bay by going to a larger engine, forget the 368, and spring for the larger displacement  but otherwise identical 425.   -  CC 

[Bloo]

The original engine has all the bosses cast in the right places for the motor mounts and all the accessories. It has all the holes in the right places for the sensors, drilled and tapped with the right threads, and everything fits. Going forward in time, it's parts match what is shown in the factory books for your make model and year.

 

With a junkyard engine, you don't know any of that.

[C Carl]

O.K. Off to the mechanic. Now : how are you selecting the right shop for the work? (Hint : the search will not necessarily be price based - as I say, you will still be far ahead of the game when the work is done).   -  CC 

[Rusty_OToole]

$1000 - $1400 sounds high for a camshaft. And it doesn't seem reasonable that they can replace the whole motor for less than the cam. Are both prices from the same shop?

 

I'm also wondering how they can offer a 5 year warranty on a 35 - 40 year old motor if you get my drift.

Edited May 10, 2018 by Rusty_OToole (see edit history)

[Rusty_OToole]

Rockauto shows a cam and kit with lifters, timing chain and gears and assembly lube for $221. This is for a stock cam. Sealed Power brand.

 

Should be possible to do the job in a day.  Add a few bucks for oil, filter, gaskets, etc and $1000  doesn't seem out of line. I seriously doubt you could get a decent engine installed for less.

 

Incidentally this would be a good time to add an RV or other mild cam for extra power and mileage.

Edited May 10, 2018 by Rusty_OToole (see edit history)

[MarkV]

Rv?

[Rusty_OToole]

RV cam is an old term for a mild camshaft meant to make power all through the rev range, specifically for trailer towing, motorhomes and pickup trucks.

 

We used to rebuild Chev 350s with  RV cam,  headers, Edelbrock intake and Rochester Quadrajet for a daily driver. Get an extra 30 or 40HP without affecting driveability and increase gas mileage by 2 -3 MPG.

 

You can do a lot with a camshaft when it comes to performance. In the smog era they were made for emissions  which is what you don't want for power and mileage.

 

What is the shop rate in your area? Do you know a good mechanic who is familiar with the older models? At one time worn cams in GM cars were as familiar as cold noses on Cocker spaniels. Especially Chev V8s.

 

How many miles on your Seville?

Edited May 10, 2018 by Rusty_OToole (see edit history)

[MarkV]

Problem is I am in California so I have to get one that will favor smog 

[JustDave]

didn't the Seville come with a 403 oldsmobile engine

[Rusty_OToole]

Do they still test 1979 models? If so get a stock replacement. There are some excellent aftermarket cam suppliers in California. They could answer your questions as to whether their cams are smog legal.

[C Carl]

7 hours ago, JustDave said:

didn't the Seville come with a 403 oldsmobile engine

 

None that I know of. However if some did, I need to know. 

 

Mark, let us help you get maximum enjoyment out of your cam replacement experience. When you audition for a mechanic and cam profile, make sure to take this thread with you. Have them comment on the relative responses here. You need personal references when shopping for lawyers and mechanics. Might be a good idea to ask on Cadillac &LaSalle Club forums for a known mechanic. You should join if not already a member. As with AACA, CLC forums are open to all, member or not.   -   CC

[Rusty_OToole]

I can't believe all this drama about a simple cam replacement. You need to find an old gray haired or bald headed mechanic who is used to working on American V8s. If he was around in the 70s and 80s he has replaced plenty of GM cams.

 

You have to start by taking out the radiator to get room to remove the cam. Then the intake manifold has to come off. Strip the front of the engine of belts, water pump, timing cover. Take off the valve covers and remove the rocker arm assemblies and pushrods.

 

Now you can take out the lifters, pull the cam out of the block and remove the bottom timing chain sprocket.

 

Replace the cam, put on new timing chain and sprockets. Put the new lifters in don't forget the assembly lube. Reinstall pushrods, rocker arms, valve covers, and all the junk you took off the front of the engine.

 

Fire up the engine and run at a fast idle for 20 minutes to break in the cam. Change oil and filter.

 

Now you see why it takes so long and costs what it costs depending on shop rate in your area. Even so it is not as much work and expense as replacing a whole engine.

 

If your engine is otherwise in good shape and not too many miles on it, this is the simplest and cheapest solution.

[padgett]

Hoo boy. All I can say is a 76 Seville had a 350 with a 4.057 bore and 3.385 stroke which is a very nice revving combo and matches the Olds "corporate" 350 (FSM page 6-68) . AFAIK it was never used in an Eldo. Anyone talking about using another Caddy engine - run, do not walk.

[Rusty_OToole]

Seville used an Oldsmobile 350 engine with electronic fuel injection, the first GM car with EFI. A different system from the old Corvette mechanical system.

 

The Olds 350 was an excellent engine, better built than a Chev 350 in every way. Got better mileage too. One Olds 350 will outlast 3  Chev 350s or 10 Cadillac 368s. I don't know how you got a bad cam, I guess after 40 years anything is apt to happen.

Edited May 11, 2018 by Rusty_OToole (see edit history)

[padgett]

4 hours ago, Rusty_OToole said:

the first GM car with EFI

Err Cosworth Vega ?

[cheezestaak2000]

it looks to me like you should spend 5 bucks for a "for sale" sign for the caddy.if a simple job like a cam replacement is beyond your level of expertise, then that 40 year old car will be nothing but a money pit for you. changing a cam is basiclly a driveway job

[76 Caddy]

FWIW...1976-1979 Sevilles used the Oldsmobile sourced 350.  1980 only, Sevilles sold in California used the Olds sourced 350, all others used the 368.  1979 only, the Eldorado used the Olds sourced 350.  (info obtained from CLC 2018 directory)

 

Has the timing chain and gears been replaced??  Reason I ask is because the original gears were nylon coated and some of the nylon could have broken off and messed the timing up and/or some pieces may have oil passages blocked.

 

Tim

[C Carl]

Tim's last sentence above could have been written in double size red letters, all caps. And then repeated. MarkV, this is something you absolutely MUST do also while replacing the cam. I would also like to emphasize the obvious, in that MarkV has very little mechanical experience. We are here to help one another, and MarkV needs our help scaled to his personal situation and abilities. We all started somewhere. And while I agree 100% with everything cheezetaak2000 has written, I would add that the money and time spent getting the beautiful low mileage desirable old car running well is money and time well spent whether keeping or selling the car. And in this case, keeping the car will mean that MarkV is still far ahead. At least for a while. And during that while he will learn plenty, for better or for worse !  Although theoretically there are a few guys here who would give of their time, and hold MarkV's hand through every turn of the wrench (Rusty' immediately comes to mind - there are others), in this case I wouldn't recommend it. Even though MarkV most likely would be an attentive student. MarkV , Wes, you would find this interesting to see how much you can do yourself. But not BY yourself. There are some of your fellow AACA members who wouldn't mind playing mobile mechanic in your driveway. Kind of an odd job situation. You just need to find one close to you. AACA forums could be productive. Increase your chances by joining Cadillac and LaSalle Club immediately. CLC forums could be productive. Any car club near you has a good chance to provide who you need. And although employment is high right now, plenty of people can use a side job. You  are in an absolute epicenter of car enthusiasts, therefore this can be done. This is a perfect level of job to see how you take to dirty fingernails and skinned knuckles. No exotic equipment needed, your toolbox, enthusiasm, and new friend should do the trick ! The satisfaction you will get will be worth thrice the price you will pay. Take the time to find a patient TEACHER , and do explain it THAT way.  Go for it !          Almost 74 year old,      -  Cadillac Carl 

 

P.S.  1980 Sevilles are a totally different platform. FWD, 368 that they are, they are 4 door brothers to the Eldo of the period.

[C Carl]

On 5/10/2018 at 1:42 PM, Rusty_OToole said:

 

 

How many miles on your Seville?

 

Rusty, I went back and see that this is a garage kept car with 36,000 miles, and is in astonishing cosmetic condition. Add the fact it is in exactly the colors Wes wanted, and you have a keeper here. Running the high ZDDP Amsoil Z-Rod will be good insurance. Also as long as regular preventative maintenance is done, particularly staying ahead of potential known fuel leak issues, this will be a good toy. Yes, it will need more attention than many cars, but they were cool cars in their time, and still are ! I enjoy driving them very much. Some may call them a "heavy Chevy", but what a plush one ! I did get quite a kick out of these  being a compact (!) Cadillac at the time, but of course they are a rather large car in today's context. ?   -  CC 

[Rusty_OToole]

36000 on an Olds 350 is nothing. If well maintained it should go over 200,000 miles without major repairs. I have seen them with that many miles and more.

 

I also agree about the timing chain and gears. They were a well known failure point on all engines that used them, and the failure was as likely to be time related as mileage related. In other words the nylon gets brittle and fails with age as much as with mileage. This to me is a much more likely fault than a worn cam. Unlike Chev V8s the Olds is not known for cam failure.

 

It would be easy to check by taking off the valve covers, turning over the engine and observing the valve motion. You could put a dial indicator on any that look like they are not opening all the way. If it turns out to be just a timing chain and gears we are talking about under $50 for parts and a couple of hours of labor.

 

Incidentally you are NOT going to get a used engine with that few miles. Putting in a junkyard engine is a definite step backward for this car. Compared to fixing the engine you have.

 

Later... did a quick search and timing chain and gears available from $18 to $29, the more expensive kit includes all needed gaskets and seals. This is a MUCH easier repair than a cam change.

 

Incidentally you can get a solid steel roller chain that has no nylon teeth. It will last the life of the engine but is a little noisier. On the other hand the stock nylon one lasted almost 40 years. How long do you plan to keep the car?

Edited May 12, 2018 by Rusty_OToole (see edit history)

[C Carl]

You have had your problem diagnosed HANDS ON by old mechanics. Get a new camshaft installed by whatever  means appeals to you. DO NOT REPLACE NYLON WITH NYLON. Get the very best, most expensive timing set you can find. NOTHING made in china will do. AND RIGOROUSLY MAINTAIN SPECIFIED TORQUE FOR ASSEMBLY. Now go DO it. But not until you join CLC. Tell 'em Cadillac Carl sent you !      -  He Himself ,  CLC 10797 , Life 

[JACK M]

I often try to explain to a customer that he already has a used one.

To replace that engine with used would be a can of worms in my opinion.

This engine is a bit complicated for most of us old guys but I don't think spending $1400 on a cam replacement is out of line these days.

It would certainly be prudent to inspect that plastic cam gear for missing parts, but this engine doesn't have very many miles on it and most likely the plastic will still be intact.

Then would be the time to consider pulling the pan.

I'm my opinion unless most of the plastic teeth are missing I would live with it. A couple of small pieces of that gear wouldn't hurt anything if they got to the oil screen..

[JACK M]

4 minutes ago, C Carl said:

DO NOT REPLACE NYLON WITH NYLON. Get the very best,

Tru dat.

Most prudent to replace gears and chain on this job.

[C Carl]

Although I couldn't carry his toolbox compared with his experience, I emphatically disagree with my friend and "neighbor", Jack. Get that nylon outta there ! As Rusty correctly said, these plastic gears have a "shelf life". Past their pull date now, and in any case you will be right there anyway. You don't want to do this again do you? Good chance you need radiator work, and since it is out, DO IT. Might as well put the very best water pump possible in it at this time too, along with all new hoses and belts. (As long as nothing is made in china). I MEAN it. I have been flopping around with these cars since BEFORE  they were BORN !     -  CC 

[C Carl]

Oops ! I see Jack has clarified, and now we all agree. And Wes, we will always have your back here !   -  CC 

[cheezestaak2000]

i really didn't try to pass judgement on the caddy owner, but imho, (for whater that's worth  lol). but the satisfaction derived from doing as much of your own work on your car is very rewarding. and yes, the folks on this site are all very willing to help you. if i might make a suggestion, watching a youtube video of the job you might or might want to tackle is invaluable. as an example, my background was as a buick and olds mechanic in the late 60's and 70's. i've rebuilt just about every component on those cars. recently i needed to change a headlight bulb in my jeep. when i saw all of the stuff i had to remove to do it, i freaked out. then i looked it up on youtube, and found all i had to do was remove 2 screws. the moral is, it's never to late to learn something. as a side note, your car will be far more valuable with the original engine, than what little you would save with an engine replacement.

 

0

[Rusty_OToole]

Up until now I have been taking it for granted that the OP is right about the worn cam. Now I am having doubts. He says the compression is good, I am not sure that is possible with a bad cam. Also the Olds 350 is not known for bad cams but nylon cam gears are a known weak point.

 

If I was there I would not be investing in a new cam until I made some simple no cost tests. Like taking off the valve covers and watching the valves go up and down.

Edited May 12, 2018 by Rusty_OToole (see edit history)

[C Carl]

Rusty,  I am sure this all has been done. The search for, purchase, thrill of acquisition and agony of reality, has been thoroughly discussed on at least 4 or 5 different threads over some time. Some 80 year old mechanics dismantled it almost to the point of being able to drop new bumps in it and start zipping it up. For some reason (arthritis, age, whatever), the old boys sent him down the line after putting in a day of dismantling and evaluation. I sure hope they didn't waste time re-assembling everything (well maybe), but in any case it is time for Wes to have at it, dnd pluck all low hanging fruit in the process. Using the very highest quality parts, for example water pump regardless of cost, will pay off in the long run. Especially if the intent is to drive the thing. Oh yeah, speaking of enjoying driving, nobody but NOBODY does air conditioning systems like a Southern California specialist. Oh, alright, any Southern Boy, Texans and others, but Wes ain't there ! Do it ALL NOW,  or I guarantee you, cheezetaak2000's wise admonition will become YOUR nightmare. Nickle and dime, time after time. You want this car RIGHT, so you can drive it anywhere, any time, in style and comfort. Hey, man  : I prepared this '77s granddad, exactly 1/2 century older, to do exactly that. Of course the A/C is simpler !  See how the windshield lifts ?    -    CC

 

 

[C Carl]

Oh, and please correct me if I am wrong  : If an EXHAUST lobe is worn, conceivably the cranking compression could actually go UP ! This could reduce the duration and overlap , right.?   -  CC 

[Rusty_OToole]

If I could look over the engine I could tell what was going on in minutes. One test like I said, is to take off the valve covers and watch the valves. Another is to pop the distributor cap and turn the engine back and forth by hand, and note how far you turn the engine before the rotor moves, to assess wear in the cam drive.

 

If the engine is already torn down it should be a piece of cake to figure out if the cam and sprockets are good or not. However, a lot of mechanics don't like to work on an engine someone else took apart, for good reasons. It's too bad he let Mr. 80 do that but too late now.

 

Considering the low miles I wouldn't be too hasty to replace the water pump or other parts unnecessarily. However now it is in the OP's hands and it is up to him what he wants to do. He certainly has enough information to make an informed decision.

[Bloo]

3 hours ago, C Carl said:

Oh, and please correct me if I am wrong  : If an EXHAUST lobe is worn, conceivably the cranking compression could actually go UP ! 

 

Maybe but I doubt it. Maybe if it were just partly worn down. They don't stay like that long enough to mention. It is an exhaust lobe for sure (rather than an intake), given the symptoms

 

1 hour ago, Rusty_OToole said:

If I could look over the engine I could tell what was going on in minutes. One test like I said, is to take off the valve covers and watch the valves

 

There was an earlier thread. Although these engines are not as prone to flat camshafts as some other GM brands, this one does indeed have a flat cam lobe.

[Bloo]

13 minutes ago, mike6024 said:

I guess what Carl was saying is that a worn exhaust lobe would not cause a drop in compression. I think he is correct on that. A worn lobe would mean less lift and the valve would have a shorter open duration, spend more time in the closed position.

 

Was one of the diagnosis findings that this cylinder had low compression? If so that in itself would not imply a worn cam lobe.

 

 

 

I'm gonna have to go find the thread.

 

In theory a halfway worn lobe could increase compression. In practice, you aren't going to make it to the next town before it goes the rest of the way flat. Nailing this down requires watching the valves open and close.

 

The car has the classic symptom of an exhaust valve that does not open, an unwillingness to rev up (similar to plugged exhaust), but accompanied by a rhythmic snapping in the intake. Anything that causes an exhaust valve not to open could do this, including broken valvetrain, bent pushrod, etc. IIRC a mechanic verified it was indeed a flat lobe, but would not do the cam job.

Edited May 12, 2018 by Bloo (see edit history)