Smart Car of America Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
I was thinking today about all the smarts that go kaput around 60-80k and the solutions of some people who add roadster parts to get their fortwo to go to 80k before grenading but... What about other options? I feel many smart owners and future aspiring secondhand smart purchasers would like to keep their car a long time and would be willing to spend the extra cash to do a rebuild right with aftermarket components that could make the engine last 150-200k before grenading. So what are and where are those components? Currently they don't exist and I don't know why. I have seen forged and ceramic coated pistons, heads, etc for mostly high end cars like the supra etc... so that those extremely stressed engines could even go 200k. So why not approach those companies that are already set up to manufacture that kind of stuff and get them to do it for the 600cc&700cc engines so that the new benchmark for smarts could be set with engines being able to last a predictable 150-200k. I guarantee if these parts were available and showed a doubling of engine life then there would be a flock of customers and rebuilding shops offering these new parts. I believe at some point some manufacturer will take on this undertaking but I see it happening more in the future as smarts become collector cars, antiques, or classics. Anyone else interested in these non-existent parts? Would you buy them if they were available?
 

·
Registered
Joined
·
912 Posts
Wow, they did all that with the engine still in the car. I would have pulled the engine complete and done it on the bench.

I'm far from an expert on those engines (never seen one - never available on this side of the pond) but from the photos above, the main problems were a snapped timing chain guide and gummed-up piston rings - which is from carbon buildup. Nothing can be done about the timing chain guide, but the carbon buildup is normally from either too much short-trip low-speed running, or from the engine running too rich, or poor atomization. Use a shot of injector cleaner in the fuel now and again, and avoid exclusive short-trip operation! Get it out on the motorway frequently.

I have heard that the roadster engines last longer because they have an oil cooler. Makes sense (and that could conceivably have something to do with that snapped chain guide).
 

·
Registered
Joined
·
5,944 Posts
I was thinking today about all the smarts that go kaput around 60-80k and the solutions of some people who add roadster parts to get their fortwo to go to 80k before grenading but... What about other options? I feel many smart owners and future aspiring secondhand smart purchasers would like to keep their car a long time and would be willing to spend the extra cash to do a rebuild right with aftermarket components that could make the engine last 150-200k before grenading. So what are and where are those components? Currently they don't exist and I don't know why. I have seen forged and ceramic coated pistons, heads, etc for mostly high end cars like the supra etc... so that those extremely stressed engines could even go 200k. So why not approach those companies that are already set up to manufacture that kind of stuff and get them to do it for the 600cc&700cc engines so that the new benchmark for smarts could be set with engines being able to last a predictable 150-200k. I guarantee if these parts were available and showed a doubling of engine life then there would be a flock of customers and rebuilding shops offering these new parts. I believe at some point some manufacturer will take on this undertaking but I see it happening more in the future as smarts become collector cars, antiques, or classics. Anyone else interested in these non-existent parts? Would you buy them if they were available?
To me it seems a fair number of the issues that people here had were from over heating and not being warned early enough shut down. If the engine doesn't over-heat, and has clean oil in it, I would suspect that there is no reason a 451 engine couldn't go to 200K+. There also does seem to be some valve guide issues as well, but I'm not sure how widespread those are; however, some robustness added in that area certainly couldn't hurt.

The 60-700cc engines are from the 450 models, and there aren't near as many of them in the states. I've read where many of them have to be rebuilt at around 60K miles, but that may also be a result of a lot of short trips that tend to be the case in Europe where everything is pretty close together. I'm not sure the US would have exactly the same issues. If the engine had clean oil and a good air filter, and isn't driven hard and put away wet, then I'm thinking 100K miles is probably doable for a 450. Again, I'm not sure what the weak points of the 450 engines are.
 

·
Registered
Joined
·
493 Posts
having many cars with small displacement engines, the key to longevity of these engines, is CLEAN OIL, CLEAN AIR, REGULAR SERVICING AND INSPECTION.

USE ONLY TOP GRADE OILS (I PREFER MOBILE ONE) AND PREMIUM FILTERS
AND SOME THINK THIS IS A PAIN, BUT PREMIUM (91 OCTANE OR ABOVE) GAS.

TIMING CHAIN FAILURE CAN BE REDUCED WITH BETTER OIL ALONE, IT PROVIDES LUBRICITY NECESSARY TO MINIMIZE FRICTION AND WEAR.
steveg.
 

·
Registered
Joined
·
4,505 Posts
The enemy is high oil temperatures and also the exhaust manifolds crack and lean out the middle cylinder, leading to compression loss though piston melting. Change oil frequently, ideally install an oil cooler and check the exhaust manifold regularly for cracks.

Ceramic coated pistons or not, the piston will melt if the cylinder runs lean all the time. The non-visual symptom of a cracked manifold is surging at steady speed. If your car is doing this, stop driving it immediately!

Metallurgy on the sprockets for the oil pump drive and cam drive are not so hot on some cars too.
 
1 - 8 of 8 Posts
Top