Water in engine: 500SL

[chrisbamford]

Hi. I have just had the head gaskets replaced, and the heads skimmed on my 1991 500SL. There was water in the engine not surprisingly, but the engine ran relatively smoothly, without knocks, when I had the garage look at the car. The garage have just informed me that there is a noticeable knocking sound coming from the engine after they put it back together. The knock is related to the engine speed. They tell me that as there was water in the sump it would probably be cheaper for me to buy a new/recon/secondhand engine. Obviously I am absolutely staggered to hear this. Particularly as the head gasket work has already cost a small fortune. I'm not sure I can even afford to have any more work done. Equally I can't afford to just scrap the car either. Does anyone have any idea what the best course of action is, or how much it would cost to replace this engine? Has anyone any advice, or comments about what the garage have told me? I am so disappointed I cannot even describe how I feel. Any advice would be gratefully received. b4mmy@mac.com

 

[ant500sl]

I have a great deal of sympathy for you, I once had my SL at a dealer for six weeks to rectify a fault. They couldn't repair it and wanted £1600 for "diagnostic work". Turned out to be a faulty distributor cap which I replaced myself for 50 quid. Take a bow Mercedes of Mansfield I'm sure if you employed mechanics and not "technicians" you might understand the workings of the cars you sell a little better.

Following a blown head gasket and oil in the water, any garage of even basic capability I imagine would check to make sure the bearings aren't shot before doing a several thousand pound job.
I would say you have good cause for complaint although where garages are involved it can be a rather laborious and unpleasant process.

I would recommend getting a second or third opinion before taking a particular course of action as work on these engines can be horrendously expensive, which you probably already know.

There are a number of special tools required for these engines, if you didn't use a specialist or dealer could it be possible they made a mess of the rebuild?

Good luck and try not to lose to much sleep over it.

 

[Arnie]

Do not fit a "replacement" engine as in most cases these are just "working" engines taken from scrapped cars. However, maybe you can reconsider a fully reconditioned engine from a reputable place.

There are some places that will recondition your existing engine and do a good job, but first get expert help to determine what exactly is wrong. It may be something simple, like the timing chain replaced incorrectly

All anyone can do on this forum is to give you some ideas and maybe's, but without looking at the car it will be hard to tell.

The V8's are very robust and I would get some epert advice before making decisions.

 

[Andy]

Hi

Sorry to hear of your problems. The problem here is that if there was so
much water getting into the cylinders. There would not of been any way they could of run it for any length of time to acertain if there was any other damage. With out running the risk of hydrolocking. The water which can not compressed could cause servere damage to the block.

To acertain the problem,would be to to remove the pistons & check. The cylinder heads has to come off. The sump removed. Easier with the engine removed. To push out the piston from the top. So you have stripped the engine & encured more expense before even getting any where near the problem. So it would be
easier & quicker & probably cheaper the fit an engine in this case.

Good luck

Regards

Andy @ www.mercedesservicing.com