I just bought a 240d with an air cleaner mount nut in the engine. (Price was appropriate for the issue.)

The PO dropped it in the intake and now the engine has a bit of a knock. I'm not exceptionally worried about saving the engine but think it's worth trying. The car is a manual transmission which is what I really want for my 300d turbo, and if I can't fix this one I'll pull the engine and transmission, transmission into the 300 and maybe down the road throw a largeish cheap gas engine in the 240 as a sleeper.

First thing though I want to see if I can save the 240. Does anyone have any good trick/suggestions for getting it out of the cylinder? I'm planning on pulling the intake and glow plugs and seeing what I can see.

I did a search and the only similar post I found suggested pulling the pre combustion chambers.

Question 1-
How long does it take to R and R a head or the pre combustion chambers? Anything special I should know?

Question 2-
Is it more likely that the engine is done (bent rod or smashed bearing)? The PO drove it a couple blocks like this, so I ran it for 30 seconds to get it on the tow dolly. Seemed to have smooth power (for what it is). Part of me just wants to drive it as a test of how tough these motors really are, but I know that's a bad idea.

To remove and refit pre-chambers you need special tools which if you ain't already got will make this a rather expensive way to do things.

I reckon you're best off removing the head and checking. You might find the nut before you get that far - you might not.

If the nut is in the cylinder expect a whole heap of damage - not much unswept volume in a diesel engine

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Other than a gasket kit and a few hours work you have nothing to lose by pulling the head so I'd go that way. There IS chance that the nut is stuck behind the intake valve in the port and that might be what you're hearing so I'd pull the intake manifold first and see what you can see. If the nut is there you just remove it and I'd run thru a valve adjustment (always a good plan on these) and see what you get - might be OK.

On making a sleeper out of the 240 - look thoroughly for rust first! These tend to rust significantly and you don't want to bolt in 300-400 HP only to twist up the chassis. The rust can be well hidden in them so start at the rear jack pockets, the rear window channel, and under the battery box as well as a general check. BTW - I'd suggest a small block Ford (a 5.0 would be a good choice) w/aluminum heads to keep the weight down. They're pretty small and fit lots of applications better than a Chevy.

Best of luck to you

Dan

Thanks for the info. Good to know about the special tools for the chambers beforehand. If I can't see it with the intake off, I'll do the head.
Dan - any swap is a ways off, but that's pretty much what I was thinking. I've been a ford guy for a while, so I'd go with what I know.

Thanks again.

It's a pretty small opening from the valve so if something made it into the cylinder I'd be surprised if it couldn't be fished out with a magnet after removing the injector/glow plug/prechamber. The prechamber opening is 14 or 15 mm in diameter round hole directly into the combustion chamber/cylinder.

Whilst the pre-chamber has a big hole at the top is has very small holes at the bottom which from a practical purpose prevent any fishing exercises

From a different thread for a different engine (OM603 3.0L to 3.5L cylinder head interchangeable?) but they look much like this

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

So I got the head off. Hopefully my pictures come through below.
As I hope you can see, a 240d can be QUITE effective at crushing a nut. The damage seems to be out of the valve travel. (Valves aren't as big as the cutout.) The nut embedded by about .07" inches the top of the piston.

My questions: How thick is a piston? Is it likely to burn through if I run it? The walls don't seem scratched and #3 seems to have MORE wobble than #2 (the nut smasher) Is it possible that the impact slightly widened the piston?

Any thoughts would be welcome.

Thanks

__________________
'83 300D turbo diesel (334k daily commuter)
SOLD '80 240D 4 speed manual, #2 piston pitted from crushing a 10mm nut. Running it 'till it burns through.
'78 F-150 300cid 4spd od (with my great unkle's original sales receipt)
SOLD '66 Ford P-350 delivery truck (almost driveable)
'49 Dodge B1D (1 ton Pilothouse era truck) not running but all there, candidate for om617 and 4x4 conversion when money permits.

Pictures

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__________________
'83 300D turbo diesel (334k daily commuter)
SOLD '80 240D 4 speed manual, #2 piston pitted from crushing a 10mm nut. Running it 'till it burns through.
'78 F-150 300cid 4spd od (with my great unkle's original sales receipt)
SOLD '66 Ford P-350 delivery truck (almost driveable)
'49 Dodge B1D (1 ton Pilothouse era truck) not running but all there, candidate for om617 and 4x4 conversion when money permits.

Picture

Attached Thumbnails

 

__________________
'83 300D turbo diesel (334k daily commuter)
SOLD '80 240D 4 speed manual, #2 piston pitted from crushing a 10mm nut. Running it 'till it burns through.
'78 F-150 300cid 4spd od (with my great unkle's original sales receipt)
SOLD '66 Ford P-350 delivery truck (almost driveable)
'49 Dodge B1D (1 ton Pilothouse era truck) not running but all there, candidate for om617 and 4x4 conversion when money permits.

Uploading from an old iPhone in the middle of the desert.

Attached Thumbnails

 

__________________
'83 300D turbo diesel (334k daily commuter)
SOLD '80 240D 4 speed manual, #2 piston pitted from crushing a 10mm nut. Running it 'till it burns through.
'78 F-150 300cid 4spd od (with my great unkle's original sales receipt)
SOLD '66 Ford P-350 delivery truck (almost driveable)
'49 Dodge B1D (1 ton Pilothouse era truck) not running but all there, candidate for om617 and 4x4 conversion when money permits.

I'm trying.

Attached Thumbnails

 

__________________
'83 300D turbo diesel (334k daily commuter)
SOLD '80 240D 4 speed manual, #2 piston pitted from crushing a 10mm nut. Running it 'till it burns through.
'78 F-150 300cid 4spd od (with my great unkle's original sales receipt)
SOLD '66 Ford P-350 delivery truck (almost driveable)
'49 Dodge B1D (1 ton Pilothouse era truck) not running but all there, candidate for om617 and 4x4 conversion when money permits.

That damage isn't good. Ideally the piston ought to be replaced.

However, I can understand why many wouldn't as people often feel they are in the realms of uneconomical repairs.

How much damage has been made to the head?

The first thing to check is the height of the piston protrusion above the block and then make an assessment from there. Compare this height with the measured heights of the other cylinders as well as the data in the FSM.

Blending the impact damage with a dremel tool might be appropriate to stop stress cracks so long as the connecting rod hasn't been bent.

__________________
1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Head appears almost undamaged. It took it like an anvil. I'll check the height tonight but will likely put it back together and run it a while. If the engine comes out, I'm going to put the 617 turbo in there instead because the interior is better than my other one. And I want a manual transmission.

Should I wire brush the ends of the pre combustion chambers or is that a no-no?

__________________
'83 300D turbo diesel (334k daily commuter)
SOLD '80 240D 4 speed manual, #2 piston pitted from crushing a 10mm nut. Running it 'till it burns through.
'78 F-150 300cid 4spd od (with my great unkle's original sales receipt)
SOLD '66 Ford P-350 delivery truck (almost driveable)
'49 Dodge B1D (1 ton Pilothouse era truck) not running but all there, candidate for om617 and 4x4 conversion when money permits.

I always like experimentation. If it were me, I'd likely reassemble it and drive it. What's the worse that can happen?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Yeah