1976 Mercedes w115 OM605 swap

[classicbenz]

Hey guys, 

thought I would start a thread to document the build of my om605 swap on my w115. 

the current om617 runs perfect. It’s just abit slow and the 4 speed manual makes the gearing terrible on the motor way. 

I know most people go for 606’s. But the car is currently 5 cylinder diesel so I want to keep it 5 cylinder and it also sounds awesome as a 5 pot. 😬 

[classicbenz]

Here is the car currently, looks the part but it’s not the fastest thing in the world 😂

[classicbenz]

Sourced a 605 from a 98 w210 with 100k miles on. Engine is super clean too which is a huge bonus. Come with the engine loom for the glow plugs too which will make life easier. I know it’s an na. But for the power planning on running the na engine will handle it fine. I'm only looking around 230-250 hp. I don’t want it to be ballistic, but having abit of get up and go will be mega.

I’ve ordered a full gasket kit, metal impeller coolant pump, small coolant pump pulley, throttle cable kit, om603 fuel filter housing, 6mm mechanical pump, injector rebuild to 150bar pop pressure,

Also ordered a 6 speed manual from a 2006 slk, it should fit the engine (hopefully) lol. Just hoping it fits in the tunnel as I don’t really want to start hammering or cutting the shell too much if I can help it. The slk box is quite small very similar in size to w123 gearbox. And looks smaller than a w124 box. So hopefully that will fit 🤞🏻

[classicbenz]

Picture of the fuel filter housing, will make piping up the mech pump easy peasy.



Gearbox arrived today and I’m happy to say it fits the engine perfect, just have to hope it fits the tunnel now and the box will be strong enough to handle the power and torque. Will order the budget clutch kit from dpuk and the shifter setup should be an easy job to install once I know lengths.

[classicbenz]

Current engine in the bay, will be for sale soon if any one is after a good running 617, not sure on mileage, but the inside is clean, I’ve done the valve clearances, it’s been serviced with genuine parts around 400 miles ago, has 5 new glow plugs fitted, new injector spill pipes, has an 80 amp alternator upgrade fitted too.

Also have a good 4 speed manual, with new clutch kit and new slave cylinder, new shifter bushes.

So if anyone has a 617 with huge blow by or a 616 that wants an upgrade. Drop me a message.

[giuliettaevo]

The om605 is a very nice engine, you'll be very happy with it.

We've put one in a w123 for a friend. Mechanical pump and om606 turbo, probably just over 200bhp now. Drives very nice.

[jjeffries]

Cool project!

John

[classicbenz]

Haven’t done much with the car yet, been working on the engine though.

Got the engine on the stand and stripped down. I’ve replaced every gasket in the engine other than the head gasket. The engine is really clean inside too, looks like it’s had a well maintained easy life 😬

New metal impeller water pump, with a billet smaller pulley. Painted the housing too. And fitted the block cooling mod.

Hot washed the rocker cover so it’s ready for paint. Hot washed the sump too whilst it was off so I can drill out the block for the turbo oil return.

Replaced the glow plugs and thank the lord they came out easily. (Which is rare with these engines)

Injectors were removed and sent off for cleaning, testing, and opening pressure changed to 135 bar turbo specs.

All new alternator belt tensioner, pulleys, belt etc for the front end.

6mm mechanical pump had arrived to fit too.

Om603 fuel filter housing with banjos so it’s easier to pipe up the mechanical pump.

New manifolds from kangaroos team racing, both inlet and air exhaust.

That’s about at the minute. Will get the pump on this week and get it back together. Will run it up on the floor once it’s together to make sure it runs right and has no oil leaks

[classicbenz]

If you want to follow the progress over on my instagram my user is @banks.164

[joe1976]

This is gonna be awesome.

I mean more awesome.

awesomer...?

[biturbo228]

Love a good 5-cylinder diesel. Drove my dad's Alfa JTD around for a while and you get a little hint of Audi Quattro warble near the upper rev range, and that was full factory silenced.

[legend]

Love this, those manifolds are beautiful

[stealthstylz]

I'm sure I've seen you knocking around in this but can't remember where.

Conversion looks great.

[mato1844]

I like that strategy, how does the engine fit on the subframe, does the 5Cyl require modifications?

[classicbenz]

Sept 26, 2024 12:03:45 GMT stealthstylz said:

I'm sure I've seen you knocking around in this but can't remember where.

Conversion looks great.

I’m based around Stafford area, midlands. If you have seen me it would be around there I would of thought

[classicbenz]

Sept 27, 2024 23:21:55 GMT mato1844 said:

I like that strategy, how does the engine fit on the subframe, does the 5Cyl require modifications?

You have to modify the subframe slightly, nothing major though. Just some cutting out and boxing In. Then custom mounts 

[classicbenz]

Rocker cover is back from paint now, so I can finish putting it together with the fuel pipes and leak off, can run it up on the stand then to make sure we have no oil leaks before putting it in. Turbo should be here next week too 😬







Drilled out the block and tapped the threads for turbo oil return

[classicbenz]

6mm fuel pump now fitted, along with 603 fuel filter housing so I can use the banjo fittings instead of the plastic ones.

refitted all the front end of the engine. New tensioner kit, and ribbed belt, new vacuum pump gasket, etc,

also Drilled out the inlet bolts and tapped to 8mm as the 7mm threads are notoriously bad for pulling the threads out. 

[stealthstylz]

Oct 7, 2024 12:56:30 GMT classicbenz said:

Sept 26, 2024 12:03:45 GMT stealthstylz said:

I'm sure I've seen you knocking around in this but can't remember where.

Conversion looks great.

I’m based around Stafford area, midlands. If you have seen me it would be around there I would of thought

Ah that's where it was, not local to me we were on a family day out and spotted you lol.

[classicbenz]

Fitted the rocker cover today and test fitted the injector lines as they need slight modifications to fit with the new pump. I’ll then remove them and clean them up. Although you won’t see them with the inlet on. Still want it to be right.

Oil feed and returns for the turbo arrived today, so just waiting on the wuhan war whistle now 😬