Engine swap!

I like the OM617 - very reliable engine. However, some might say that it's not powerful enough. If the replacement 617 is a known good engine and is included in the price, it would seem a fair price for the work. I would think that the swap should be very straight-forward.

I would take the time to to a top-end overhaul with at least new valve seals. Also, change the engine mounts whilst at it.

 

Yes, that would not be a straight drop-in replacement. However, I think that G-Restorations could advise on your options.

 

Hello I had a remanufactured 617 dropped into my SWB 300GD as a result of cylinder head failure (well cracked 5 times and still running - but struggling on the hills). So whilst the G is 1985, in effect I had a new 617 put in. I had the injectors done, The rule pump set to slightly over fuel. Had a bigger bore stainless exhaust fitted and made sure the valve clearance were done every 6-10,000 miles plus full oil change and flush with Forte at every service. And finally made sure the linkages allowed for full throttle opening.. All this and whilst the low torque was great, you always felt you were beating the G to death to get it to keep up with any sort of traffic.... and I have the 5 speed manual box in. In the end I had a 617a (turbo version) dropped in it via ScouseG - different feeling vehicle entirely. Pulls through to 80mph on the flat, will go up most of our motorway hills at 70mph. Keeps up with traffic, and all this with the fuel pump mod or intercooler. Also before I had a silencer put in - the straight side exist exhaust whistled, spat and howled :-)) All that said it has less low end torque - compromise to allow for the impact of turbo boost once you are at 1,800rpm I guess - so might be a bit less off road friendly if your doing the heavy stuff? Hope that helps. Simon

Hi Arnie Yep agree the 617 can get to 80mph.. (or even 85 :-)) takes a while, and the rev limits for 617 to 617a are about the same so even with the 617a it's not a speed that's comfortable :-). I think your point about wheel spinning on the 617 is a better way of highlighting the point about what you trade for better pick up, and a feeling of not thrashing it, when you go from the 617 to the 617a which is less low down pulling power. I always enjoyed the G on country lanes, you just learn to keep the momentum up. And for off road in particular I think the low end torque on the 617 means you can virtually use any gear... even better with an auto I assume. But then again there's low range - as long as your on the type of ground suitable for permanent 4WD. I still remember being surprised when I turned onto a mates steep drive in 2nd and the newly 617a powered just would not have it at all - had to go to first. The 617 simply used to tootle up it! So as with many things, it comes down to personal choice and end use. Do a lot of road and I suspect you'll prefer the 617a. for off road and country lanes you may well find the 617 ticks the boxes. Horse's for courses and all that. Simon

Sorry, by 'auto-box', I meant automatic gearbox. Autos go very well with diesels, though you might lose a smidgen on economy. It's a personal choice, but I would probably prefer it to a 5-speed manual. The 460, 300GD Auto cabrio now spends all of its time in the mountains in Italy, 50% of the time on dirt tracks so perhaps the standard 617 is a good choice, then. I didn't imagine that the turbo version would have reduced, low-speed torque, but I guess MB must have made the right choice when fitting non-turbo, Diesel, engines for military vehicles. I notice also that the new military Gs are now all (?) automatics - at least in the brochures.

 

 

' In-Line Pump' ??

 

Injection Pump

  you are right almost every thing is automatic even the big

   6x6 pinzgauers i know the off road boys say manual is the way to go

    my pal said that to the factory test drivers on the schockl

​    so they took him in a 4x4 pinz it was over 45deg steep over rocks

    then asked him to change down a gear WOW only the test driver was laughing

     my mate was white as a sheet as they sped back down backwards 

     then the took the 6x6 pinz easy peezy kick down and up she went

     and with the G you can lock it in any gear

     for me no option with a club foot just glad it works for me

 

Hi Ref the which box question. I found this link helped a lot - as will the ever knowledgeable Gav on here if needed : http://4x4abc.com/Mercedes-Benz.G-Class.manuals/transmissions/getriebe.html Ref speed regulation on an auto Vs manual I'm no expert (can't you tell :-)) but would not the auto version of slipping the clutch, be lightly breaking? I'm guessing most 4X4 autobox setups allow for some breaking effect to be maintained Vs the normal 'coasting' you have on road only ones - even in drive. My 85 SL used to advise using 3rd or 2nd on the autobox for steep 'alpine' hill descents to 'conserve your brakes for emergencies :-). Mind you it also said any Merc dealer would be happy to take the hard top off and store it for you so you could enjoy the soft top driving experience during summer - but I digress.. Ta Simon

Ref Auto Vs Manual - as you say personal pref, and I suspect things have moved on... But if you've a got a bit of time on your hands :-) Harald Pietschmann has a few views on the subject: http://www.4x4abc.com/4WD101/index.html I found it an interesting read. Remember to look though his links about styles & tips etc. I suspect I'll never get to the outer edge of the off-road envelope so for us mortals it will always be about what we like to drive - but a good read! Thanks Simon

Oh and to pick up on another question the IP Mod (I know the Injector Pump bit has already been explained) is a change to the (usually Bosch) pump that alters is fuel delivery characteristics/set up - There is loads on the extreme version of this on the web - the Sweds/Finish seem really keen on this. So there is more to it than just upping the fuel deliver, and I think involves, even in base versions involves lots of tinkering with the internals, But as Adrian was saying what you end up with on the 617a (it helps the 617 as well, but less so) is your turbo spooling up at 400rpm vs 1,800rpm, with if you also add an intercooler, limited to no black smoke under load. So more power earlier to offset the loss of torque (due to lower initial compression on the 617a to allow for turbo boost I think - sure more knowledgable will correct if I'm wrong). To be honest you can lost in the subject of IP mods and as I am sure Adrian would agree the best thing to do is find a specialist who understands Bosch pumps and get them to 'liberate' some more power. Again I used to have a link for the actual how to 'tutorial' on this. But a good overview can be found by reading down this merc owners club thread: http://mercedesforum.com/forum/diesel-performance-49/injection-pump-fuel... they do talk about all the things you can try yourself. Enjoy :-)) Simon

I would put your engine up for sale here, german ebay and other european sites