Engine replacement VS rebuild

pontiac
sunfire

#1

hi, i’ve a question, i have a 2000 pontiac sunfire with a tad over 218,000 miles it runs fair uses about a half quart of oil per 3000 mile (which is the interval i change the oil) i’ve been told that the timing chain is stretched and could snap and that it would cost a estimated $1200 (parts and labor) to replace it… i’ve called around and can get a used engine for about $350-450, the AC system also needs to be completely replaced do to a busted pump. would it be worth rebuilding this engine/replacing it with a used one with less miles. or just run the car till it dies and replace the whole car…


#2

Unless you really love the car, I’d just keep driving it until it dies and replace it. The cost of an engine replacement and A/C fix will likely exceed the value of the car.


#3

Is the chain rattling??? How are they determining it’s stretched. A stretched chain is more likely to slip a tooth then break.

The AC system is separate from the engine. So if you get a used engine…the AC components won’t be part of it.

The 1/2 quart oil consumption every 3k miles…while not desirable…is NOT really bad.

The two things I’d consider…is either fixing the chain and the AC…or getting another vehicle. That $350-$450 for a used engine does not include labor…Add another $1500 for labor. I doubt your vehicle is worth that much money.


#4

I agree. Too many other potential problems on a car car with little value, even with a new motor. Run it till it drops and be searching for a replacement.


#5

I’d either live with the AC or fix the AC and that decision is mostly about how hot is the climate where you live. If the loose timing chain is affecting the function of the valves then fix the timing chain. If it is just noisy, then just live with it at this point.

If you put in a used engine it might not be much better than what you have now. I doubt you can get a used engine INSTALLED for anything close to $400 so perhaps you intend to do the engine switch yourself. If it is a DIY job and you’ve tackled this kind of complicated job before then go for it, but I’d but I’d consider changing out the timing chain on that “used” engine before putting it in the car.

A 2000 Sunfire sounds like a car you just run until she quits at this point.


#6

Run the Sunfire until it will run no more. Sell it for parts…then move on.


#7

I agree, do nothing now. It’s just about fall, you should be able to get by without a/c for the next 6 months or more. As for repairing/replacing the engine, I’d run it till it breaks while putting as much money as I could into savings (make it a weekly habit) for your next car.


#8

The shop at quoted $1200 to replace the chain, what sort of place was it?
Dealer, chain, independent?
You might find a better price at a good independent shop.


#9

I never heard of a stretched chain. Belt, maybe. But chain???


#10

How has the diagnosis of a stretched timing chain been determined? If it’s not rattling how do they know this problem exists?

As to financial feasibility, the car is not worth the cost of an engine rebuild and A/C repair.


#11

If it’s the same as with bicycle chains, the chain doesn’t actually stretch, it lengthens due to pivot wear.

Sheldon Brown explains it:

“The major cause of chain “stretch” is wearing away of the metal where the link pin rotates inside of the bushing (or the “bushing” part of the inside plate) as the chain links flex and straighten as the chain goes onto and off of the sprockets. If you take apart an old, worn-out chain, you can easily see the little notches worn into the sides of the link pins by the inside edges of the bushings.”


#12
I never heard of a stretched chain. Belt, maybe. But chain????

Just the opposite. Chains will stretch over time. Usually after 250k miles. ALL chains will eventually stretch.

Belts are made of polyurethane and reinforced fiberglass. Very difficult for a belt to stretch…but they do break after. 100k miles about their limit.


#13

I agree that $1200 for a timing chain is too much. I had one done on a Chevy V8 for $250 10 years ago. Get a quote from a good independent shop. As per a previous discussion, a noisy timing chain is not about to break suddenly.

If you can’t get the chain fixed for $500 or so, forget it and just keep driving while changing oil and filter regularly till the car quits. Then sell for parts or scrap.

If you even think of fixing the AC, forget that too. My mother-in-law’s Pontiac Tempest had the same problem and replacing a compressor and purging the system will run about $1000.


#14
I had one done on a Chevy V8 for $250 10 years ago.

It really depends on the vehicle. Some vehicles you have to drop the oil pan. There are several gaskets. I replaced one on a Isuzu…Overhead cam…TWO chains. Several gaskets…Had to drop the pan because the front two bolts - bolted into the lower timing chain cover. And to drop the pan you had to loosen the engine mounts and raise the engine to remove the pan. The complexity of some vehicles can easily warrant a $1,200 charge.


#15

wow, i wasn’t expecting this many replays, the reason for the $1200 for the chain replacement was mostly labor. (and it’s a independant shop) and do to the fact that i have a jammed tranny mount that would have to be cut out. (the bolt refuses to remove even with a impact gun) anyway personally i think the rattle that the guy is hearing is a weak tensioner as the sound is in exact time with it’s movement (he argued otherwise which is why i’m not going back to that shop) as for as the AC system i’m not sure exactly what happen. it was working i was driving along the engine bucked down there was a loud BLING sound power returned and so did heat. there is no visible damage to the pump but several AC shops said it busted and the entire system would need to be replaced do to metal shavings in the system,. i can take the heat, but the engine is my primary concern, a new tensioner is only $50, and i can do that work my self. (i hope…) i will definitely be finding a new shop to take my car to for the major work. thanks guys and gals!


#16

Pretty much agree. I sure wouldn’t bother with another engine but I would double check on the cost of having the timing chain/belt replaced. You can get upwards to 3-400K with a little repair and proper maintenance.

Edit: Sorry didn’t read everything first. The noise from a timing chain hitting the case will be a little different than a tensioner noise and it will be coming from behind the case. An irregular metal tapping noise. One good mechanic that listened to mine didn’t know what it was either so it can be misdiagnosed. You can test it for a short time by taking the serpentine belt off and running the engine to see if the noise goes away. Also the tensioner pulley is really a weak point and can be replaced for about $20.