Author Topic: 1975 450se.....should I?!  (Read 1610 times)


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Re: 1975 450se.....should I?!
« Reply #30 on: 04 July 2020, 04:03 PM »
..So would a river..
And.."it running fine"  sat in garage"'.. Tell me about people selling cars.. It brings out the worst people, and the worst IN people. That's why people like me always pay double. i am gullible and passionate enough to believe them, again and again, and not vicious enough to ever sell a car without telling the truth, or wanting someone else to "just get a good deal for once"


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Re: 1975 450se.....should I?!
« Reply #31 on: 04 July 2020, 07:26 PM »
Well, I got the car home.  I spent the rest of the day on the engine.  It's as I suspected......the engine has seized.   I mean really bad.  I removed both cylinder heads, and ALL 8 cylinders had severe rust in them.  I have never seen anything like this.  Being a 1975 U.S. model, it has the secondary air injection on it for the catalysts.  When I remove the pipe from the air pump to the chain tensioner water came out of it.  I'm not sure how water got in the engine, and in all 8 cylinders. Even if I were able to free the engine, the cylinder walls are so bad/perforated with rust that it would destroy the piston rings.  So I'm going to have to put another engine in.  This is going to be fun. haha  But I knew the risks from the beginning.

Hmm that sucks :-\  Is there an option to hone the cylinders or bore to oversize?  My rebuilding knowledge is non - existent pretty much so excuse me if this is a stupid tangent ;D
1977 450 SEL 6.9 - Astralsilber

TJ 450

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Re: 1975 450se.....should I?!
« Reply #32 on: 04 July 2020, 11:23 PM »
Sounds like it’s time for an engine tear down. Being an M117, oversize pistons/ rings should be available so if the damage is within any of the repair stages it should be good. The heads might be rotten though.

1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500


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Re: 1975 450se.....should I?!
« Reply #33 on: 05 July 2020, 04:29 AM »
So I removed both cylinder heads, and both are not corroded or rotten.  Something bad happened somewhere though.  When I drained the oil it was full of coolant.  Naturally the inside of the block was just as filthy/rusty. 

I have three spare engines here at home.  It'll be less costly to put new rings and bearing in one of the engines that isn't seized.  I suppose the original engine could be bored and fitted with new oversized pistons, but that'll be a last resort.  This block is really a boat anchor.  Though, if the rust/perforation in the cylinders is too bad the block could always be sleeved.  But again, that would be an expensive last resort.  I'm not concerned with keeping the original engine with the car, so I don't mind the engine having a different engine number from the original. 
1966 250se coupe`, black/dark green leather
1970 600 midnight blue/parchment leather
1971 300sel 6.3, papyrus white/dark red leather
1971 280sel Black/black leather
1973 300sel 4.5, silver blue metallic/blue leather
1976 280s astral silver/blue MB Tex


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Re: 1975 450se.....should I?!
« Reply #34 on: 24 November 2020, 11:40 AM »
Hi, what's the update on this car? I was reading through and came top the end with no real ending.  ;D