Thread: My Mercedes' Dead Motor

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Here in OZ Fords are both rare and expensive to buy parts for,The real hot Fords arn't the 5.0 V8 but the local XR6 Turbo ,which is both faster and cheaper to run than the V8,which in the eyes of the young is 20th century technology and no longer relevent.The Use of Jap technology is popular because :1,toyotas are very reliable and 2,Toyota and Nissan build enourmous horsepower for peanut money and spares are as close as the nearest dealer,who has them onthe shelf,Unlike ford who never seem to carry anything but filters and plugs. http://www.webwombat.com.au/motoring...s/xrt_xr6t.htm

Originally posted by Kimbrelljk
Matt167 & drg84 - Yea, that is/was our intent. Either rebuild what we got or find another engine. A rebuilt engine is a little expensive. I'm trying to convince my wife (it is her wheels) that we should buy an old junker with a decent engine and put our engine on the stand and rebuild a little at a time - plus we got our own MBZ junkyard for parts. The "302" idea just seems cool,especially against a 5000.00 rebuit and install. I'm a prev hot rodder (my love was my '70 chevelle malibu BUT was ordered new with SS "stuff" (Muncie 4sp, buckets, factory guages, 12bolt rear,etc). But, honestly, the diesel with the injection junk along with the MBZ vacuum stuff??????? A little intimidating. So, I had heard that swithing to the Ford V8 was not too bad and there was a kit that really helped make the swap do-able. Now I think it would be more project than what it is worth.
So, more than likely, we will find a used engine or junk car to work with.
What's wrong with my engine? Our son checked and added oil and did not put the cap back on. The next day my wife called me and said there was a puddle of oil under the car and that the cap was gone. She keeps oil in the car. I told her to add oil and go to a parts store and buy a generic cap (Help!). Well, the clerk could not think independently of the computer and told her they did not have anything that would work. It is just a plain two pronged cap that goes in the slots and turns! So, I told her to put a cloth in the hole and go to work, that evening we would fix it. Well, the cloth (MY MISTAKE) was too close to the overhead cam and was drawn in the engine and quikly starved something(s) of oil. The chain is broke, it was squealing like a stuck pig B4 it died.
WHEW!!!
It is a beautiful old car, and my wife's heart is broken. We bought the car from the original owner for a grand!
So, to finally sum up - Yea I think we will go back with a diesel and keep "original" as possible.
Thank-you to all those reading and helping!!!!

If ya were a little closer, I'd sell ya the short block, cam, chain, butthe shipping would be killer and you have a MBZ junkyard right where you are so it makes no sense. Actully, my uncle who lives in Georgia ( pretty close to stone mountian, can't remember the town ) said he knew about an all MBZ junkyard and he was going to get little parts I needed for an interior resto like, door handles and a new lock cylender but, they didn't have those parts, probably the same junkyard.

Hey everybody! Thanks to all of you who are taking time to offer help and advice. I even learned about the "Holden".

Well, for anybody interested, my wife and I started pulling junk of the Benz motor yesterday to see if we could figure out what stopped spinning and broke the chain. Now, any motor expert / diesel experts / MBZ people out there?

The chain is snapped. Doesn't that indicate that something being driven by the chain stopped and the crank kept going and the chain gave way. The car last ran while sitting in the driveway. The engine had been squealing when running. I was trying to hear where the noise was coming from and shut off the car, and it would not crank back up. Only later did we notice a hole in the rocker cover and discovered the chain had broken. We have removed the rocker assemblies and the cam spins like a top. Could it have seized up, and now months later be free to spin with no resistance at all? The vacuum pump is chain driven, but it is just a sprocket with a disk on it with a lobed surface that pushes a small pring loaded wheel in the housing that pumps. All that seems free. The tension sprocket spins. Next we are going to look at bottom of the motor. The oil pump has its own chain down there. ??? All this is being done while the engine is still in the car. We hoped that we could find the culprit and repair right in the car.
Any thoughts?

A confession here,Mercmad is my nickname because i'm MAD on MERCEDES.I have .besides a couple of rods,5 mercedes.I did have 8 but it was getting embarressing to have all these cars parked around the street.
OK,to your timing chain problem,
It's common on high mileage mercedes because the chain is a service item that is supposed to be changed every 100,000 miles.
These engines are known to cover up to 1,000,000 miles
Yes i million miles,the world record is held by a taxi,the same model as yours with nearly two million miles with the one driver. So the timing chain is nothing to get concerned about.
To fix the problem,remove the aircon if it has it,under the water neck is a large bolt device,thats the tensioner spring housing,remove the water neck,remove the tensioner housing to take the pressure off the tensioner.If the chain is still in place,buy a new chain and connect it to the old one so it feeds down through the engine on the "DRIVERS SIDE".
Never turn a mercedes engine backwards,toomany things like tensioner rails and injection pumps can be damaged.
Next,before you attempt to turn the engine,you must remove the rocker arms under the cam.You can push the valve springs down carefully and remove the retaining clips and the arms.Once the arms are out of the way(it's easier than it sounds) you can rotate the engine with out worrying about the valves being damaged.Then you must fit a 27 mm socket to the nut in the middle of the crank pulley,someone must lay under the car and turn this,another person must feed AND keep the chain tight at the top.
It is important to keep the chain tight as it can bunch up in the bottom and damage the slides.
when it comes to the top ,up the other side, connect it on the cam wheel with the spring clip facing in the direction of travel which is clockwise.
I do this with two people on top,one to feed the chain and one to pull the old one through.
No danger of it getting bunched up.
BUT,if you have lost the chain down eitherside,get a light to see and a hooked wire to pull the chain back up. carefully and very gently rock the engine back and forth with the crankpully while keeping the chain tight.This is to clear any bunching of the chain.
It is simple to remove the bottom of the sump,which you may have to do if the chain has dropped to far,but it must still come out the top.
Ihave joined flexible wire like heavy guitar strings to broken chains that have dropped from sight,wound the wire around until I COULD HOOK A NEW CHAIN ON THE END AND PULLED IT THROUGH.
thats being drastic .but it works out in the end.
Once you have the chain hooked up then it's time to check the injection pump timing.
I'll leave it there,let us know how you got on.Any major difficulties and I'll fax the work shop manual pages to you.

Wow mercman! Generous of you.. kudos.

But... didn't he blitz the valves when the chain broke while the engine was turning?

Sometimes...sometimes... it happens,but on the fours ,fives and sixes they usually just seize,it's the alloy block V8 that grenades when the chain breaks,then you start looking for a later 500 series engine or ....small block conversion.I have 1983 380,which has every single merc option,i bought it for $200 dollars because the chain had broken and destroyed the left hand bank,i fitted a second hand head ,valves etc and a second hand piston, rod & BEARING!,and got it going for under a grand.Super luxo sedan for 1200 bucks!!.reminds me of the days when i built flatties,

KUDOS from me as well mercmad!!! I will print your advice and proceed. Thank-you again for the input and knowledge. This is the only forum I've been involved with........IMPRESSIVE!

Also, remember that a rag was eaten by the engine via the oil fill hole. So, I assumed that something had seized up. Do you think it is possible that a chunk of rag got between the chain and a sprocket and that broke the chain? The engine developed a squeal (bearing?) a day or so later. While the car was sitting in the driveway idling, we were trying to find out about where on the engine the noise was coming from. Then it got a little louder and I ask my wife to shut the engine down. It would not turn over after that. No loud bang or grind or anything b4 shut down. And, oddly it wasn't until way later (we shut the hood and walked away from the dead) that we opened the hood to tinker with it and discovered a hole in the rocker cover and subsequently the broke chain - so I don't think the valves or pistons were hurt (any further at least) Anyway, we have taken the rockers off and the cam spins freely. The vacuum pump shaft seems to be ok. The tension sprocket between the cam and vacuum pump turns ok. Our next step is to go to the bottom of the engine. We can only get to (and see) the chain on the driver's side and of course as it disappears around the vacuum pump sprocket down to the crank. I think it is bunched up down there.
MERCMAD and all ya'll - THANKS!

Check the water pump,They will squeel.and you can drop the front half of the sump really easily,it's held on with 5 mm allen head bolts. I honestly cannot think of anything inside a merc engine that wopuld cause the squeeling noise unless it was the chain being forced against the side of the chain housing.
Good luck!

Kimbrelljk: Absoluteley the chain could be broken by injesting the rag. I would expect the rag to be reeeeeally screwed up too. What is directly below the hole in the rocker cover? I presume this hole aint spoze to be there?

I'm looking at doing something similar, but I would like to go diesel-to-diesel with a lot more torque and climbing power. When I was stationed in Germany I saw all manner of 'tuned' 123-body Mercedes. I'm wondering if anyone knows any good links like 'how-to-put-a-mercedes-truck-engine-into-your-240D'? I live on a mountain, so a transaxle for the front wheels would be nice... probably not gonna happen though.

http:/home.earthlink.net deton 8r/benz.htm

This site lists the parts used. There is not a kit available from this individual, however it does list the parts used in this conversion.

hope this helps!!!! will be doing a 302 conversion on a 450 sel soon.

Robert

saw a 300 TD on a toyota 4X4 truck chassie, the sub frames were removed and the entire unibody was bolted to those mounts, on the chassie. Why MB diesel. you could find an old powerstroke or cummings from older used trucks, easy to find, cheaper parts. I used to have a '83 240D, had a disassembled motor, was going to put in 350 Chevy but lost interest, ended up tearing it apart and junking the remains. My dad still has a mint original '83 W/ 4spd.

Originally posted by jramshu
I found a site that sold the exact conversion you are looking for but I can't seem to find it again. I also have a 76 240D. I was thinking about a 302 myself, such a small car. Drive train set up off center also.
www.benzbin.com has tons of harder to find parts, might be able to find something thru them.

here is a good site for all European cars
Shoreline

The 123 Merc You can fit a 302 in with slight engine crossmember mods.
However, the steering linkages will run into the starter. You have to build yourself rack steering system or do a complete "subframe".