SKcats fleet. Taxi spec 250D barge.

[Skcat]

4 hours ago, Talbot said:

Got any underbonnet shots?  Can work out if it's an OM602 or an OM605.

It's a om602

 

[Talbot]

Lovely!  With the worlds most complex accelerator linkage.  Quite why a cable wasn't acceptable is anyone's guess!

[HMC]

Just now, Talbot said:

Lovely!  With the worlds most complex accelerator linkage.  Quite why a cable wasn't acceptable is anyone's guess!

They seem to have really gone to town with those linkages in period- IIRC the M104 straight 6 twincam had a bewilderingly complex set up, partly buried under the inlet manifold so usually neglected and stiff.

[DavidB]

I was in two minds over buying that when it for sale in Chester - mind won over heart in my case.

[Peter C]

I bought this:

About ten years ago, a full fat 500SL, with what should have been a very potent V8. However, I got it cheap because it couldn’t pull skin off a rice pudding. Turned out that a plastic clip was broken on the throttle linkage, which only allowed about 1/4 of the throttle to open with the accelerator pedal fully depressed. 

I fixed the clip with a cable tie and on the test drive I was taken back by the V8’s power to the point that I shot past a speed camera and gained three points in the process.

[Skcat]

Started changing so bits on the 250D starting with the waterpump;

It was pretty bad, it said INA on the impeller so I don't think it was orginal. 

All back on, so I got started with the intake manifold gasket and glow plugs, the intake was on extremely tight. Not sure who put it on, every bolt came loose apart from the final one. Thankfully the bolt grips got it off. Not sure what I would do without those. 

All the glow plugs came out without any issue. They all varied in resistance and seemingly manufacturer. Although none of them had any text on them, so who knows who made any of them. 

I've bought all bosch replacements as recommended by @Scrubworks. It's was already getting dark so I just stuck the pulleys back on and left it for tomorrow. 

[Scrubworks]

That's one good thing about north-south engines with timing chains, the water pump is generally pretty easy to access.  I went for a Graf pump when I did mine. I hope you'll be going round those intake ports with some degreaser and a little brush, it's filthy.

[Skcat]

All five glow plugs are back in; 

Now on to the leaking injector:

My only worry is what is the plastic ring that goes around the injector. It's not on the diagram. 

Going to need to chissel whatever that crap is off and keep the head undamaged! 

Next job is too change the thermostat. 

[beko1987]

That looks like silicone or something equally horrible. Good luck! 

[Skcat]

I've been incredibly busy with work so the merc has gone unloved with the intake off. I went to out the serpentine belt back on and when tensioning it it I used a bar and smashed a vacuum hose:

The big pipe goes too the brake booster and the smaller bit (I smashed off) goes too all the vacuum funtions for the drivetrain such as the engine shut off valve. I'm no diesel mechanic but it's just a hose with a check valve. 

I gave up trying to get the pipe off so took it off with a grinder. The little check valves are a little awkward to buy so I bought a generic one. Did some testing and it turns out the 33 year old one had failed anyway. I bought a T pipe thing and some new clear line, This is the result.

I will probably try to fit it all better and replace the legnth of yellow pipe as it looks a bit naff against the new bit. But all the funtions seem too work again. 

I managed to find the rounded intake bolt from mercedes on ebay for a couple pounds, as it was so cheap I snapped it up. Decided to clean up the old fixings while it's all apart.

Hopefully it will all be back together tommrow! 

[Skcat]

I put all the injectors back in and new line to the injectors but I still have a leak. I think my pre chambers are leaking. I have ordered a splined attachment to tighten the prechamber lock rings back down, hopefully that will solve the issue.

 

[Skcat]

I ordered the prechamber locking tool from ebay, I will just have a go tightening It down, maybe thay will solve the leak. Failing that I will pull it out.

At least I found time to change the rest of the vacum pipe. I've got the only old diesel mercadies with a clear tube now. Probably will yellow fairly quick!

[Nullzwei]

On 11/01/2025 at 18:59, Skcat said:

I've been incredibly busy with work so the merc has gone unloved with the intake off. I went to out the serpentine belt back on and when tensioning it it I used a bar and smashed a vacuum hose:

 

The OE Mercedes wheel brace/ wrench end fits exactly into the black plastic block that moves the metal spring that tensions the aux belt tensioner. Makes putting the fixing bolt back in place nice and easy. User friendly design back then.

Good idea also to check the damping is still working on the little aux system shock absorber. Few years back i cracked a power steering pump mount because of a duff aux system damper.    

[Skcat]

7 hours ago, Nullzwei said:

The OE Mercedes wheel brace/ wrench end fits exactly into the black plastic block that moves the metal spring that tensions the aux belt tensioner. Makes putting the fixing bolt back in place nice and easy. User friendly design back then.

That's smart, sadly I dont have any tools with mine untill tonight. Went on a big trip and picked up loads of good parts for mine! 

Got a pair of rot free orginal front wings, sacco panels, tool kit, drivers electric window motor and mechism, drivers mirror, interior vents that are broken on mine, dash pad, tool kit, washer nozzles, interior light unit. Probably loads more, the guy told me It was getting scrapped on Tuesday so I've been on a 350 mile trip after work tonight to get as many parts for mine as possible. 

[Skcat]

After getting this tool and wrenching on the prechamber my diesel leak is now gone! Finally time to go back together. 

Fitted the washer jets from the donor car and they all seem to work now! 

[Skcat]

I think that's the leak sorted, so it went all back together, I went to the jet wash and cleaned up the block as good as I could. Looks far better and ive not seen any oily puddles under it so far. 

Took some time to fit a drivers mirror in the correct colour. 

Much more to carry on with but it's getting better 

[yes oui si]

Lovely old thing, that

[Skcat]

next job was putting the used but much newer bonnet pad from the donor car on the 250d

when i get more time i will have a go getting the drivers window fixed!

 

[Schaefft]

Love seeing the progress on this!

[Skcat]

I had some spare time last night so fitted the donors cars electric window and linkage. I would recommend it should be done at day, especially if the window quit working in the up direction and sized up. still another broken thing fixed!