SL/R129: Engine overhaul intervals
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From: Malaysia
'92 R129 300SL-24, '01 W210 E240, '03 W220 S320, '02 745Li
Engine overhaul intervals
The 300SL-24 is about 14 years old, with just under 100,000 miles on the clock. To my knowledge there's never been a full engine overhaul, but there has been work done whenever something's gone wrong.
Now, the car's be acting up a bit recently. Occasionally during stop-start city driving in relatively heavy traffic, the revs will suddenly and momentarily drop. The battery light flashes momentarily too. Sometimes I catch it in time, give it a bit of gas, and the car keeps on going. Other times it stalls.
I've also been noticing a bit of flutter from the engine, as if it's misfiring a bit. Not too sure what is wrong, but do you all think it's time for an overhaul, to fix this problem, and as a preventive thing, too?
Now, the car's be acting up a bit recently. Occasionally during stop-start city driving in relatively heavy traffic, the revs will suddenly and momentarily drop. The battery light flashes momentarily too. Sometimes I catch it in time, give it a bit of gas, and the car keeps on going. Other times it stalls.
I've also been noticing a bit of flutter from the engine, as if it's misfiring a bit. Not too sure what is wrong, but do you all think it's time for an overhaul, to fix this problem, and as a preventive thing, too?
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From: Manchester, UK
500 SL R129, Blue - 1991. Mini Cooper S, Works Kit Silver - 2007. Mitsubishi FTO, Silver - 1996.
Yes pressure test the heads asap, and even then you might find there is some water in the sump. I would try taking the plugs off one side at a time... get someone to start the car and watch for what comes out. If its water, or white, and your pressure test was positive it may be a tiny leak... so get the gaskets done asap or you may have to skim the heads and that would be expensive. Also, check the colour of your exhaust gas. The engine is fairly bullet proof and it takes a lot of damage to stop it... but by that time its fairly serious.
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From: Socal
1991 300sl 5 speed manual
These cars are bullett proof I agree
I had my 93 300ce until it had 150k miles on it and it still was the same compression and tightness the day I purchased it 3 years earlyer with 100k miles. I just purchased a 129 300 sl 5 speed manual with 75kmiles. I must tell You Im looking forward to the many years of reliable driving. There is a 93 300ce with the same engine as you have in your car the 3.2 strait 6 engine with (are you sitting down?) 370,000 miles. Enjoy the pics here is the link. Jeff
http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT
http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT
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Almost a Member!
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From: Malaysia
'92 R129 300SL-24, '01 W210 E240, '03 W220 S320, '02 745Li
Okay, the car's back. Initially, the mechanic confirmed it was some vacuum leak. HE finally fixed it by changing the idle hose. Car's fine now. However, it still takes a bit to start it up cold. The car will start with a turn of the key, but it would take maybe 4-8 seconds to properly start, but often it will cut out and require another restart.
It also feels a tad bit short on power these days. Anyways, the mechanic's come back with a quote for a full engine overhaul, and it's the equivalent of US$4,000. Didn't quite expect it to be that much, and it's about 15% of the car's current market value here. Dunno, really... It's not critical yet, is it? The mechanic, of course recommends it...
It also feels a tad bit short on power these days. Anyways, the mechanic's come back with a quote for a full engine overhaul, and it's the equivalent of US$4,000. Didn't quite expect it to be that much, and it's about 15% of the car's current market value here. Dunno, really... It's not critical yet, is it? The mechanic, of course recommends it...
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From: West Coast, USA
2 SL with every Brabus mods available & Class A competition sound system
Originally Posted by j0shua
Okay, the car's back. Initially, the mechanic confirmed it was some vacuum leak. HE finally fixed it by changing the idle hose. Car's fine now. However, it still takes a bit to start it up cold. The car will start with a turn of the key, but it would take maybe 4-8 seconds to properly start, but often it will cut out and require another restart.
It also feels a tad bit short on power these days. Anyways, the mechanic's come back with a quote for a full engine overhaul, and it's the equivalent of US$4,000. Didn't quite expect it to be that much, and it's about 15% of the car's current market value here. Dunno, really... It's not critical yet, is it? The mechanic, of course recommends it...
It also feels a tad bit short on power these days. Anyways, the mechanic's come back with a quote for a full engine overhaul, and it's the equivalent of US$4,000. Didn't quite expect it to be that much, and it's about 15% of the car's current market value here. Dunno, really... It's not critical yet, is it? The mechanic, of course recommends it...
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From: Maryland
'87 W124, '95 R129, '04 G35
I don't know your car well to speak for it. But engine overhaul at 100K on the M109? I think your mechanic is getting his yacht ready for the season and need a sucker to pay for it.
I would have the compression test done before an engine overhaul. When was the last time you had a tune up?
I would have the compression test done before an engine overhaul. When was the last time you had a tune up?
