I thought it’d be a good thing to address a lot of the comments and questions that I get on this site in a “Newsletter” type format. I apologize in advance for any delays in replies to my comments. I have been a little busy lately. Without going into too much personal detail, my life has been full with work changes, home projects, my baby girl and soon-to-arrive baby boy! As a result, I figure it’d be easier to do a bulk reply to the stuff I get versus emailing each one individually – plus, it would give others more information and insight on our wonderful rides.
I can’t promise any schedule that I’ll follow for these updates. It will vary based on the questions I get, and my free time. For now, I’ll say an update every month, and maybe I can stick to that! Without further ado, these are the backlog of questions I have received from a few months back to today.
A client of mine out here in Mumbai, India has a 1972 280 SE W108 car whose original engine has gone bust and is beyond repairs. He is interested in retaining the car and souping it up a bit. I came across a article in Mercedes enthusiast magazine Issue 6 of April 2012 where someone has retrofitted a 6.3l V8 engine into a 108 chasis. Would like to know if it is a viable option to do the conversion and if so what all is involved. If not what is the most powerful engine that can be transplanted in this chasis easily. Obviously we would also need the complete refurbished engine along with all the necessary parts to do the conversion.
Well, let’s start from the perspective of the 6.3 in a 108. It will fit. You’ll need the engine, trans, and rear axle to do this right. Anything less would be a very high-revving engine with a slow top speed and terrible economy. You will need V8 front springs (3.5/4.5) to deal with the huge iron lump, although it shouldn’t be too heavy for these it will be too heavy for the 6-cyl springs. Now, the 6.3 was a low-production vehicle. The engines are rare and costly, as are parts, and rebuilding can cost tens of thousands. I’d guesstimate that this endeavor in the US would run a solid $10k without touching the trans or rear axle and hoping they are in good used shape. Since you aren’t keeping it original, here are other options that will also fit and be a lot less of a headache: A 4.2 M116, a 5.0 M117, a 5.6 M117, and if you feel daring, an M119 (any displacement)… other engines will fit, it sounds like you want V8 power though, so this is why I stuck to these. These are all readily available, parts are as well, and a rebuild would cost a fraction of what that of an M100 and its transmission would. The 5.6 in euro-spec would be MORE power than the 6.3 while giving better performance from the lighter aluminum block – you may even be able to keep the 6-cyl springs. Use the 4.5’s rear axle for econ or the 3.5’s for acceleration. I could go into it further but a search on the MB vintage forums can show you other people who have done this swap type and some who have gone even further to bore/stroke a 4.5 iron block into a 5.6, and pop it into a 280 SE/C! As far as most powerful… that’d probably be a supercharged SBC like DEBENZ has done.
I bought my father’s low mileage 1967 250s 4-door sedan. Water pump failure forced significant down-time now the carbs are plugged with alcohol induced sludge. My dad had always wanted a 250se and I a 4.5. I now have a good friend into swapping GM fuel injected engines into older cars. He prefers LS v8 but I want a Atlas I6 DOHC 4.2l trailblazer transplant.
Well, to each his own! I mean, if you’re going to swap in a GM engine, personally I would do a SBC or an LS but… hey, if this is what you want, it’s your call. I have no experience with this engine, so I can’t say if it’s a wise choice or a fool’s errand. I also have no idea if that would even fit in the 108. Just keep in mind it’s a truck engine, so it’s probably designed for low-end torque… you can pull stumps, but don’t enter any drag races! As far as what engines I would personally use, see my suggestions above. I can go into a bit further here: I really, really would love to try a swap to an M119 with its matching trans. You’re going to have a wiring nightmare either way, and the M119 is a fairly reliable, well-respected engine, and in “E500E” format, quite a powerhouse.
I am looking to purchase a 1973 280SE 4.5 located in Greensboro NC. I need to have the car inspected. Any reccomendations on who may be able to look over the car?
Thanks to my delay in the reply, I am assuming this has already lapsed – sorry! But if not, the best thing to do is to post a thread in the Vintage MB forum and ask. there are likely members in or around any given area on the planet that a vintage car can be found that can look for you. This is possibly the next best thing to finding a pro mechanic well-versed in these old girls (rare find, impossible in some areas) that can look for you.
hi thinking of buying a 250 se yet it has the later 3.5 v8 ? would this devalue the car or poss a good thing cheers Frank
This is an opinion thing, honestly. Some may argue the original engine has value for purists while others would say the 3.5 makes it way more usable in the modern world while maintaining MB heritage. To me, I’d much rather have a 250SE 3.5 than a 250SE – but if the 3.5 were a rustbucket and the 6 were pure and unmolested with great original body lines, no rust etc…. I’d choose the 6! As far as value, it really boils down to what you (or any other person buying it) would actually pay. I assume the swap is done correctly with the 3.5 rear and proper speedo and gearing.
I am looking for yellow fuel injector for mercedes 1970 300sel 3.5l chassis 109.
I have not had any of these in years, sorry! You can use the Vintage Forum, check ebay, or check a wrecker. This brings up a good point: I don’t actually have a stockpile of 108/109 parts (anymore). I would always suggest starting a forum thread. In the rare case I DO have a part, I will reply and let you know, but you’re reaching a lot of people on the forums and you may be able to get the part you need in a few days.
I have a 109.057. It seems that in the winter months a warm start issue appears. I have replaced seals and the like, but still it persists. My german mechanic says it may have something to do with california winter gas? In any event, it hates a 20 minute warm start. Secondly, I am looking to start buying interior replacement, for the carpet, seats, etc. Do you have any recommendations on who to go for quality original workmanship? And what of the undercarpet rubber spongelike things, are they to be reused? or can they be bought new? In any event, I am a newbie. thanks much
Believe it or not, the warm start issue is actually common on these D-Jets. There are tons of speculative causes. The most likely is that some gas blends (especially those with ethanol content) actually boils in the fuel rails during heat soak, causing cavitation in the lines. There can be other causes as well, such as leaky injectors, leaky CSV, etc. If you are sure your injectors aren’t leaking, where I’d start is by putting a fuel pressure gauge on the lines and measuring pressure in the rails before / during those start attempts. If you aren’t around 30PSI, your D-Jet pump may have a bad check valve. Easy fix is to install an aftermarket check valve in the engine bay. You can also try raising the pressure to about 32-35 PSI for those warm starts to prevent the vaporization of the fuel – if the pressure indicates 28-30 when you try to start but it doesn’t fire, this can help. The downside is you may need to then dial back your mixture. As far as interior replacement, I hear a lot of positives about GAHH. You’d typically re-use the rubber-foam mats from under the old carpet unless they’re in terrible shape and need replacement.
I have a 1972 250C in need of restoration it is a on owner car and has been stored in my garage for about 14 years and has not been driven it was running and driving when parked but has many issues now due to the neglect and chipmonks etc …
Honestly, I don’t know too much about the 114/115 chassis. But speaking from experience in ressurecting my 108 after sitting: Fuel lines, hoses, belts, brake lines (hard and soft), calipers, door seals, window/windshield seals, engine mounts, subframe mounts, and anything else that’s rubber or protected by rubber will probably need replacement. You will likely need to shop vac the HVAC and even then you may not get all the squirrel/chipmonk/misc rodent nuts etc. out of the system without pulling it all. The seat padding may have holes and missing padding as well. Take your time, go through everything, change every oil/fluid, let it warm up fully OUTSIDE the garage, and then check all the fluids after a good 30 minute idle and change again if needed. Don’t be in a hurry to drive it around the block before you sort everything you need to go, turn, and stop. This includes tires! Old rubber dryrots and belts separate even if they look fine.
I have a 1973 MB, 280 SE 4.5 l. Im looking to put 15″ rims on it. Im running P20570 R 14 inch tires. MB has a lot of their cars with 5 X 112 mm bolt pattern. Im looking everywhere for my factory offset on my rims – the number somewhere between 25 and 40 mm and If its negative or positive. This info is really hard to find. can you help me ? Please email it to me. Im in Ontario Canada and I see for example quite a few 1990 ,, 15″ rims for sale off a 190D car. That car has 5 X 112 mm bolt pattern and data is easy to find on the internet (such as the offset). My concern is will this rim fit. ?Or should I be taking the original spare tire out of the trunk , find a way to measure the offset and then stick to that. ? Accordinging will 15 X6″ rim with tire size P20560R15 ” with a 5X 112 mm bolt pattern with its offset (depending on the car) fit my 1973 Original rim with tire size today of P20570R14 and lets say an Offet of 30 mm ?
Well my research may be wrong but it LOOKS like a positive offset around 23-30mm. If you want to play it safe, I have seen 14″ bundt wheels stock on the 126 chassis AND 15″ wheels on the 126 so this leads me to assume any 126 chassis wheel will fit the 108 as far as offset, clearance etc. I have seen pictures of 108s/109s with these wheels as well but I can’t promise they will fit and work fine without spacers but I assume that this would be fine. The only “Safe” option otherwise is the super-rare 15″ bundt wheel – you have to be a big bundt fan to spend that much on those, IMO, vs 126 wheels. FWIW, I don’t think the 107 (280SL / 450SL / 380SL / 560SL) ever changed the wheel offset specs, and these came with anything from 14″ steels with caps to 14″ bundts to 15″ alloys – maybe even 16″ alloys. As far as tire size for those 15s, I’d do 205/65/15. They’re negligibly larger (818 revs/mile vs 822 for 205/70/14 25.5″/64.77cm dia vs 25.4″/64.516cm), so you will not have any clearance issues with those. I ran 205/70/14 on my 108 too, slightly taller and wider than stock FYI but they rode and handled very well!
Looking for a diagram of wiring harness for a 71 280se Mercedes. Can you help me
I do not have one, and I don’t know if the FSM(s) do either. You can ask on the Vintage MB forum, but it may be better / easier to help with your specific wiring issue and tell you what wire(s) go where on the plug(s) you are having issues with! Post a thread on the forums with specifics.
Fyi, i own a 1970 Mercedes w108-2.8cc. (108.016-60-0xxxxx). Recently my Merz was a little slow in moving on the highways…I checked the carbs and found one of it was looks a dirt and I planned to change both the zenith carbs to new units (Is it advisable?) and if I wanted to purchase two zenith carbs how much would it cost me and do you have them for sale?) or any other twin Carbs like solex will give my s280 w108 more strength Please advise and Thank you very much.
Having no experience with the carb setups, I can only speak from what I’ve seen on the forums. Most people do Weber conversions unless you can find a Zenith/Solex guru. Pretty much everyone who has done the conversion to Webers has praised them and the improved drive and economy. It may wind up costing less to get the conversion plates and rebuilt Webers than it will to get those other pesky units rebuilt. Because not only do you need them rebuilt, you need someone who can then sync them, and get the setup just right, and this is easier to do with the Webers. But again, either do a search or make a post on the Vintage MB forum, because you will get direct answers from those with firsthand experience.