This article is very timely for me because just yesterday,Ihad to take my daughter's '02 Dodge Neon in to my mechanic for a similar issue. My daughter told me a loud squealing had abruptly started 2 days ago.Examining the belts, I could see that they were (over-)due to be replaced. It's good that I let her drive my car to school and take hers into the shop, because I soon discovered the problem went significantly deeper.The belts were shot because the pulley tensioner had frozen and was no longer turning. The Serpentine was dragging over the tensioner, causing extreme friction and now, a catastrophic failure. The heat destroyed the tensioner pulley which had literally melted off its shaft bushing.
All of this happened because about 12 months ago, he (my long-time trusted mechanic) had advised that the center engine mount was broken, and needed replacement. Since it was estimated to cost several hundred dollars to replace due to the transverse mounted orientation, I asked if she could continue to drive it without risk. His professional response, was "Yes, but the engine torque will eventually cause other, seemingly un-related complications at any time". I had forgotten about the advice until yesterday.Today, My daughter has a new tensioner, new serpentine, and a new center engine mount, and the car runs smoother than it ever has. And the cost to replace the mount was "parts" only, since the major labor cost was already incurred in the tensioner repair.
Ouch! That reminds me of my own engine mount nightmare on a Nissan Sentra some 20-odd years ago. I was pretty broke, so could not afford expensive car repairs. Apparently, a transmission fluid leak was slowly destroying first one, and then two of my four engine mount gaskets. For reasons I still can't understand, my mechanic decided to interpret my "I can't afford expensive car repairs so whatever can wait should" statement to mean these, also. But he also didn't tell me about the problem! I discovered it when I moved to Northern California, got a new mechanic, and asked why there was this vibration at 65 mph. It was pricey to repair, but sure made a difference.
It's my impression that engine mounts always fail sooner or later, because of the decay of the rubber that's involved. I had a reliable Camry where one of the mounts was bad, and it was too expensive to fix, so I just left it. But it definitely left an imbalance.
The other point is that real-world engine mount experience is never like those car shows on Spike TV, where they make a really nice bracket with a couple of bolt holes so it can't torque, and then they cushion it with a rain forest's worth of rubber. On real cars, most of the engine mounts don't seem to be all that well made.
It seems that motor mounts can fail quickly in a highly stressed racing application; however, usually in a more modest street application it seems that the rubber holds-up well; unless, exposed to oil or other petroleum based liquids. Lacking that degrading oil or ATF element, I have seen motor mounts last for the life of very high mileage cars.
The wide range in design seems to be whether the motor mount solely relies upon the bonded rubber to hold the engine assembly, or if there is an interlocking metal feature to back-up the connection. The Chevrolet V8 "Safety Mounts" from about the mid 1970s on have that interlock. The Chevrolet Corvair flat 6 mounts had that interlock. The Ford Taurus sub-frame has that interlock (they just have a corrosion salt trap that makes the steel portions potentially unreliable; unless, the galvanized recall part is installed.) The 1964 Oldsmobile V8 mount had no steel interlock, just the bonded rubber. From the readers comments it sounds like other vehicles such as the Econoline van also had no metal interlock back-up of the rubber attachment.
Clearly, it could be very bad when engines or sub-assemblies fall-out onto the road, or even when the engine can shift causing the throttle to pull-on harder and the transmission linkage to lock-up. This is why there were NHTSB discussions with GM in the early 1970s. This regulatory oversight probably facilitated the upgraded Chevrolet V8 motor mount design in the late 1970s.
This story brings to mind my father's 1970 Olds Delta 88. He got the smaller engine, a 350 V8. It had an automatic and all the other power options. I drove a 1969 Austin Healey, a 1969 MG B and a 1973 Triumph 750. All very small engines. When all of those were down, I would borrow the Olds (which by then was my parent's third car). My father offered to sell it to me for $25, but I declined. Whenever I borrowed it I would run out of cash. I was used to getting at least 25 MPG in the city and the Olds got 10.
Well, being used to manual transmissions I was at a light and wanted to rev the engine to impress someone. So, i put it in neutral and revved it. It didn't run well for a week after that. We had to do a complete tune-up.
We never had the engine mount fail, but I did burn out a wheel bearing trying to get out of a snowy parking lot once. The weight distribution was just terrible for that.
The Station Wagon ran smoother with good engine mounts too.
Yeah, it was a "big engine" by many of today's automobile standards, but not near as big as some of the V8s in that era. The 1964 Vista Cruiser Station Wagon I was driving had the high-performance 330 cid Cutlass Rocket V8 . . . not near as big as the 385 hp 425 cid (predecessor to the 455 cid) V8 in my Dad's 4600# Toronado.
Ironically with lower gearing and 3600# weight, that 1964 station wagon was actually quicker than the Toronado, or my 1995 Cobra Mustang. (But it was not near as quick as my 3000# 327cid SB Chevy V8 powered Corvair.) It's worth noting, with it's higher-compression engine (10.25:1) using 97 octane premium, the station wagon got as high as 24 mpg on the highway with a fresh tune-up and keeping my foot out of the 4 barrel carburator.
Hey, Dave, you really has a V8 Corvair? How on earth does a V8 engine fit into a Corvair engine compartment. My first car was a Corvair, and it had a tiny engine compartment. I loved that little car, but it certainly had a handful of its own problems.
Had. Yes, I had a V8 Corvair. From 1974 to 1976, I built and painted the 1969 Chevrolet Corvair with the Kelmark Conversion Kit (Later renamed Mid-Engineering) to put the 327 Small block Chevrolet V8. This increased the horsepower from the stock 110 hp 164 cid flat 6, to 325 hp, 327 cid V8. I rebuilt the suspension, rewired the dash, repainted it red, and installed a black interior. The V8 Corvair in it's heyday was a daily driver, autocrossed, run at Lime Rock, and entered into shows. 0-60 mph was around 5.2 seconds.
The configuration had the engine in a cut-out where the back seat had been, on a steel box tube frame under a van type engine cover that I fiberglassed-up and carpeted. The radiator was in the old rear engine compartment, but was marginal on cooling above 50-55 mph even with three electric fans in the fiberglass shroud. The kit used the Corvair manual transaxle, turned-around and running backwards. (The V8 ran clockwise, while the Corvair flat 6 ran C'Clockwise.) The 1966 to 1969 four speed saginaw transaxles were the strongest, but even with the custom input shaft, racing u joints, four spyder differential gearset, and special oiling provisions, the transmission would fail about every 3,000 to 5,000 miles. I twisted 1 input shaft, 2 mainshafts, 4 clutch gears, 1 ring & pinion, and one set of u joints out of it from 1975 to 1984.
The engine went into a 1969 Camaro project in 1984. I was in the process of matching a 1985 4 bolt main 350 cid SB V8 to a 1966 Olds Toronado 425 THM Transaxle to the set-up, with a front radiator, when a job and location change encouraged the car projects sale. I sold a 1958 Devin (Triumph frame and 1974 Capri V6) to a stranger, the Corvair to a buddy in 1990 without the engine and transaxle. I believe the body was stripped and scrapped. I later sold the 350 engine and Transaxle in Memphis, TN. Alas, the break, and part-out demise of many project cars.
Wow, that's an amazing story. I can understand the difficulty with the cooling, since it had to be built into the back. I would imagine you didn't take corners too sharply. I'm sure you're aware Corvair's are weak on sharp turns. It's the car Ralph Nader cut his teeth on. I enjoyed mine, though.
While not as energy absorbing as rubber, polyurethane resists breakdown from oil. Aftermarket motor and transmounts are available in polyurethane. Cost is a little higher and installation is identical. I just did a froint end rebuild on my old 89 honda accord. Most all of the replaced bushings got poly instead of rubber. Only the upper control arm bushings stayed OEM rubber. My 67 Plymouth barracuda will be getting poly motor mounts, trans mount, and suspension bushings too. Sources are Energy suspension and Prothane.
I tend to challenge engineering done by an attorney trying to make a name for himself (Ralph Nader). His book "Unsafe At Any Speed" came out in 1966 after the handling problem was virtually fixed, and was full of questionable evaluation and conclusions. Like most believable lies, it had just enough truth to be difficult to challenge.
The early Corvairs from 1960 to 1963 had swing arm suspensions which could travel into positive camber causing weight jacking, but so did Porshe, VW, Lotus, and Corvette among others. From my observations, the VW Bug and VW Bus had far worse handling problems in this area than any of the others.
In 1964 Corvair added a suspension component that limited the down travel and potential negative camber.
From 1965 to 1969, the Corvair had a full independant rear suspension which virtually eliminated the issue. Corvette made this upgrade around the same time. Later on, Porshe and VW made these upgrades as well.
Rearward Weight Bias:
The stock Corvair had a rearward 30/70 weight bias that could create oversteer, which the typical driver is unprepared to deal with. So did VW Bug, VW Bus, Karman Ghia, and Porshe. Chevrolet largely tuned-this-out of the Corvair with a very low front suspension roll center design, a very stiff front sway bar, and specified low front tire pressures. This car actually had more understeer than preferred for best race handling. It could still transition to oversteer in poor traction turning conditions such as snow, ice, or sand. Naturally other cars have trouble in these conditions with poor driving techniques as well.
My V8 Corvair was mid-engine with about a 40/60 weight bias. If I moved the radiator to the front it would have been about 55/45 to 50/50 weight bias depending upon my final engine relocation. I had slightly stiffer springs for stock ride height even with more weight, I also had had wider tires in the rear for a balanced tire contact patch and horsepower to the ground. I also added a rear sway bar. This car was VERY stable and did well in the snow (unusual for a muscle car). The car still had more understeer than desired and ideally needed closer to neutral quick-transition handling by a stiffer rear sway bar, a softer front sway bar, adjustable racing shocks, and new upper A-arms for a higher front roll-center. I would joke that my Corvair was "Unsafe at Every Speed" because it could get to speed so quickly, but it was actually very safe.
Exhaust Fumes in the Car:
The heater on air cooled engines could pump oil or exhaust fumes into the car. This was true of VW, Porshe, Corvair, and others. This was worse by oil leaks from Butyl rubber O-rings on the Corvair push-rod tubes. Enthusiasts later determined that Viton O-rings effectively fixed this problem. Naturally, other oil or exhaust leaks, would need to be fixed to avoid this problem.
My Corvair had a SB Chevrolet V8 water-cooled engine with a 1967 Mustang heater mounted to the cowl below the windshield; so, this extra risk of exhaust fumes was a moot concern for my application.
Through the years the Corvair model was successfully raced by the Yenko Team and others with exceptionally good handling. I believe that Corvair was killed by the economics of manufacture, and the fact that it did not fit into the Chevrolet portfolio of products, NOT legitimate safety issues. The stripped-down economy end was better handled by Vega, Monza, and others to compete with Ford Falcon and Pinto. The marketed performance banner was to be carried by Corvette and Camaro with more horsepower than even the 180 hp turbocharged Corvair. The marketing of the Corvair was also damaged by Ralph Nader, so the "American Porshe" was discontinued.
David12345: It's not hard to find people who restore Corvairs, and there must be a good reason why that restoration market has continued successfuly for four decades. Regarding the Vega: Wasn't that the one that used an aluminum cylinder block? Didn't the block have warping problems?
My understanding is that the Vega was using an innovative high-silicon content aluminum block without steel sleeves (Except the Cosworth Version Engine). I'm not sure about block warping problems worse than other engines machined from fresh castings; however, the Vega definitely had more issues with cylinder wear until the rings were no longer sealing well, with the resultant burning lots of oil.
That's pretty good, David. I hadn't heard the counter argument to Nader's book. Thanks for the detail. I very much enjoyed my Corvair -- my first car. I can't remember why I switched to a Rambler after a couple years. I was probably facing a pricy repair job and a new used car was less expensive.
In 1964 Corvair added a suspension component that limited the down travel and potential negative POSITIVE camber.
Oops. My error.
Additional Suspension Design/Set-up Background:
The suspension design changes were to get rid of the possible heavy positive camber weight-jacking on the outside loaded wheel that could contribute to roll-over tendencies when hitting rough pavement in a hard turn with a swing axle suspension.
Street suspension alignment calls for 1 degree positive static camber, presumably for better wheel bearing load balance and tire wear. Race handling is improved by setting the camber with 1 to 2 degrees negative static camber. This could just be set on the front and independent suspensions. This negative static camber was done with lowering springs on the swing-axle suspensions.
I liked your look at the old Corvairs. Growing up, we had two of them. Aside from the constant fan belt issue, they were in fact very good cars, even in stock trim. We didn't have any other problems with them. My mother's was a '64 stock-o and my father had a '66 (?) Monza. His got hit hard three times and was repaired fine each time. Later on, my brother had a Monza Spyder Convertable. That was a pretty quick little thing. He later sold it for large $$.
Ever notice that Ralph Nader never once commented on the burning Pintos (had one - terrible car) or other deadly Ford products? Just wondering out loud here. I also agree that the Corvair was pretty safe, but different enough in handling that a poor driver often would get themselves in trouble. Just like with a Porshe or "bug". We had a car lot, so had experience with just about everything.
Your V8 Corvair must have been a heart stopper.! I had a '67 Cutlass that I installed a (real) 450 bhp 327 come 331 cid engine in. It was difficult to turn over due to the high compression. It also went through engine mounts until racing mounts were installed. I can't blame GM engineering for broken motor mounts, they were due to my abusive situation. Even stock Old's would eventually break engine mounts if you kept jumping on the gas. The early "rocket" motors really were different than a Chev. engine. All in all, the 60's and early 70's were a fun time to be a driver.
Yes, that was a fun time to be a driver . . . I still have fun with a little Cavalier. I am looking into installing a roll cage, dropping a 3.8 Liter motor and transaxle from a Pontiac, and replacing the supercharger with a turbocharger and intercooler. That combination could get me close to 300 horsepower in a 2300 pound car.
The Corvair could take quite a hit an still be "functional". In the late 1970's, a buddy bought a Corvair "parts car" that had been hit while parked. A GTO had hit it at around 40 mph head-on and pushed it on top of the Corvette parked behind it. The Corvair front was punched-in over 18" with the front suspension moved back about 8" and the steering column safety telescoping collapsed. The Corvette behind it had over $1000 damage (back then that was very big bucks), and the Corvair rear engine had been pushed forward about 2". Now here's the amazing part. We removed the front hood, opened the left front fender with a sledgehammer, replaced the left front wheel, and bent the throttle linkage until we could get about 3/4 throttle with the gas pedal down. With these relatively minor "fixes", he was able to start and gently drive this car over 20 miles down to his house in southern Delaware. Even the exhaust system was quiet with a muffler that had been punched forward about 4" and the muffler was about 1.5" shorter. I'm sure the legality of his drive was bogus with the damage sustained; even with, current registration and inspection, but it did drive! Both the GTO and Corvette needed a tow.
Good story, David. A friend of mine in the mid-1960s took his 1962 Corvair too fast around a residential corner and rolled it -- without a seatbelt. He ended up right-side up. He took a couple deep breaths and drive if home. The car was a tad scraped up on the sides, but otherwise it was in perfect working order.
In the 80s I had a buddy who was rock and roller who was "into" the 60s. He had just gotten an advance from a record deal and went out and bought himself a nice-looking Corvair convertible. Don't know what size engine it had, but in any case it was fuel injected. He knew next to nothing about cars, just knew that it looked really "cool". (And boy it sure did!)
One day he came to me complaining that there was a strong gas and exhaust smell inside the car while driving. Could I take look at it? I'm not a hard-core mechanic like you guys, but I knew enough... We parked it on the street and opened the hood - I had him start it up and give it a little gas. Immediately there was gas spraying out onto the (soon to be very hot) exhaust manifold from 3 leaking injectors. Yikes!
It was also easy to see that there was a huge crack in the manifold, with exhaust blasting out.
Well, there went the rest of his big advance... :-(
I believe Corvair was only offered with carburation. On the 1965 to 1969 Corvairs, they had a 164 cid horizontally opposed 6 cylinder engine. The 95 and 110 hp models had 2 carburators, the 140 hp models had big valves and 4 carburators, and the 180 hp model had one carburator and a turbocharger.
It sounds like either your buddies car was heavily modified for fuel injection, or more likely they were leaks in the fuel lines to the 4 carburators of the 140 horsepower, 164 cid engine. One other possibility was the aftermarket four barrel carburator in the center with the four legged intake manifold to the 140 hp heads.
Irregardless, he was lucky it didn't catch fire and burn to the ground with all that gas spraying everywhere. I suspect the cracks were in the overheated heads and integral intake manifolds.
I would agree that the late model Corvair convertible was a sharp looking car; although structurally, I liked the two door hardtop better. The convertable had additional bracing in the floor and 60 pound hydraulic dampeners in the four corners. (I guess the dampeners were to reduce unibody oil-canning vibration.) My modified V8 Corvair was a 2 door hardtop with additional "roll-bar appearing" door posts welded in. This triangulation provided a much stronger structure for better suspension tuning, and body stiffness.
"The engine had been sitting in the car without any attachments, except hoses and the throttle linkage." Yikes! Sounds like it was one hard expressway stop away from a catastrophe. The scary part is that engine mounts can fail so inconspicuously and dangerously at the same time.
At least the V8s usually were cradled on the front suspension in such a way that the forward and back movement of the engine and transmission seemed to be limited by exhaust systems, block shape, oil pan, and bellhousings nestled between the firewall and the cross-frame members. Forward and back, the worst I ever saw was a radiator "decored" by the fan and engine pulleys. The engine torque on the other hand could have the engines get positively UNGLUED. The misalignments could take-out drive shaft U-joints or unplug the spline from the back of the transmission.
Buddies that modified thier engines for more horsepower and raced them at the track often installed chains or metal turnbuckles at the front of the engine to limit travel. This chain was the cheaper recall fix that GM chose in the 1970s before the improved motor mounts came from the factory. The more serious racers would go to solid metal mounts or front plate mounts, but that added a whole new dimension to the vibration in the car.
I don't believe GM did the more standardized factory engines across marques until the later 1970s after the beefed-up mounts were standard equipment. Even then, I believe there were many unique engines to Cadillac, Pontiac, Oldsmobile, and Chevrolet until the V6s became more common.
My 1981 Volvo 240 estate suffered an interesting related problem. The electrically switched Overdrive (I'll get there, OK ?) was tripping out occasionally. Unsure what was going on, I changed its oil (ATF), but to no avail, and frankly I don't like getting inside gearbox assemblies. Soon enough, I lost all drive almost instantly, and had the car towed to my usual garage, offering everything I knew. Two days later, all good, the O/D being fixed by- new engine mounts ! The old ones having gone a little soft after 125,000 miles, were deflecting, chafing the O/D wiring on the transmission tunnel, causing an intermittent short which caused the O/D to trip out. The loss of drive was due to a worn out clutch, which came on so suddenly because of Volvo's outstanding build quality, which had allowed the lining to wear down to literally ten thousandths of an inch thickness, worn away all the rivets and fallen away during a gearchange; new clutch assembly, no damage to the flywheel, and away. So, an odd one on the engine mounts, but frankly a testament to the great engineering of real rear wheel drive Volvos. What these rebadged Fords are like, I don't know, but in terms of Engineering quality, that Volvo beat any of the many Fords I've had, though I confess I've always been happy with them.
I had an old Oldsmobile Omega that had that problem. The bad mounts also damaged the transmission. They seemed to fail regularly on that car. It finally cought fire and burned, which eliminated that problem for good.
I had a similar experience on my '68 Cougar a few years back. I stepped on the clutch pedal as I went to start the car, and things just didn't seem to disengage. In fact, the clutch felt like it was binding. What'd happened is that a motor mount had gone bad enough that the position of the engine had slipped to where the bellcrank linkage for the clutch -- which is mounted at one end on an inner fender panel and at the other end to a boss bolt on the rear of the engine -- had come out of alignment.
Fortunately the car was parked at the top of a hill and I was able to get the clutch to release just far enough to get it rolling downhill in neutral. I then *very* carefully felt for the opening in the dog teeth in the transmission and got it eased into second gear, at which point the engine started and I limped the five miles home in 2nd.
When I got home, two new motor mounts and a little clutch adjustment set everything to right again. This time, however, I opted for a set of racing motor mounts that didn't have rubber. The vibration is a little harsher, but the whole car is set up to be a little on the gritty side, anyway.
IF memory serves me, GM had a VERY serious problem w/ engine/transmission mount failures several decades ago. So much so that the gov't really came down hard on them as they continued to deny warranty claims & out-of-warranty claims for defective mounts. It was an across-the-biard problem, affecting just about every make & model from Chevrolet to Cadillac. Could it have been in the era when GM was cross-populating their vehicles with engines from their sister divisions?
I had this problem with my 1963-1/2 Ford Galaxy. It was after that that I noticed that engine mount were made with the metal interlocking and the rubber between. The rubber could fail and the metal would still hold it.
Why would they have to learn this thing all over again?
During the 60's and 70's when US manufacturers offered big, high torque engines, the standard bonded steel-rubber-steel mounts had a tendancy to de-bond. After some un-planned engine departures, the manufacturers started making interlocked or caged engine mounts where rubber separated the steel parts and isolated noise but prevented excessive engine movement in case of failure. Today, unplanned departures seldom occur but the bonding process to attach rubber to metal hasn't improved much. In my experience, a significant percentage of high-mileage cars and pick-ups have one or more faulty engine mounts. Leaking oil, road salt, solvents, phase of the moon all seem to cause debonding. Many suspension components are also steel-rubber-steel and debonding of them is an issue. Auto manufacturers have done well to engineer mounting assemblies that continue to work safely even after wear, rust and chemical decomposition have taken their toll.
I had the mounts on my dad's 66 Impala break in the middle of town at a stop sign. Main problem was, I had my Mom with me & I was 17! Throttle hung wide open scaring the fool out of me & Mom.Years later I had another 66 Impala, an SS 300hp 327. I broke several until GM recalled all models including Dad 69 Impala. The "fix" was a short cable with bolts that went from the head to the frame. Dad used the cable, I found some solid mounts at a Speed Shop.
I had a 89 Thunderbird Super Coupe that had Fluid filled motor mounts. They are known for failure because the tourque of the supercharged engine will tear them up rather quickly. Unfortunatly, when they do fail, they let the oil pan rest on the crossmember which will eventually rub through and cause futher problems. I guess every vehicle has their problem huh. Now every time I change the oil on ANY of my cars I check the motor mounts.
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