mercedes 709d... more power

[eyesaw]

I own a 709d that I have converted into a motorhome with the intent to travel europe.. problem is it is very slow to the point of being dangerous..

It currently has at the om364 4L Engine with auto box..

50mph top speed but if I hit any inclines I can just watch the speed drop off which I consider dangerous when motorway driving some times I can be doing 40/35mph

I need more power...

I'm looking at replacing the engine,gearbox and rear axle for a 814d om904la, wondered if anyone has done anything like this before and knows if it is a relatively easy task.. or if anyone knows if there are any other solutions that may help me squeeze some more power from the engine i already have.

I know there is a om364la which is a turbocharged and intercooled version of the engine I have but can't seem to find much about it...

someone please help..

Thanks in advance

es

 

[turbopete]

often the turbocharged versions were only available in LHD because of the position of the turbo relative the the steering column in a rhd vehicle

first off, how much weight has the 'camper' conversion added to the weight of the vehicle?
are all the brakes etc free? none of the older MB 'vans' were quick, even compared to similar vehicles of a similar era BUT they would usually run at UK motorway speed limits all day (although very few that im aware of ran auto gearboxes in 'van' form)

as for changing the engine, gearbox AND diff, im not sure how much you will gain compared to the amount of work that would need to be done to get it all fitted, and unless you happen to have a scrap 814d lying around complete, id imagine the cost of buying the engine etc would get quite eye watering!

as for getting more power from your own engine, well it depends what exactly you are wanting it to do. most people with a camper van are in no rush so power isnt really top of their priorities list HOWEVER there are a few things that could be done.

start by checking the engine is correct for the vehicle (not been changed and not declared on the V5) and also that the gearbox and diff ratios are correct.
check brakes are free and not binding (sticking on or over adjusted)
check filters are clean and that the injectors are giving a good spray pattern (remove and have them tested)
you could have a diesel specialist open up the injector pump to get a bit more fuel in there (it should be resealed) and check that the pump is correctly set up and not been screwed down for economy (like parcel firms etc often do) or the max rpm turned down (to limit top speed) etc
then you could look at an aftermarket or even DIY (done by a garage if necessary) turbo conversion, or scour places like ebay (europe) to try to source the 'official' parts for an 'official' turbocharged version of what you already have.

personal experience tells me that making sure that everything on your current engine is 100% efficient could be far more cost effective than replacing the engine/adding things to your current engine.

 

[eyesaw]

Thanks turbopete I will have to investigate further...

As the vehicle I have is an old ex-service platoon beaver bus... so chances are it has been restricted for economy..

After striping all bus seats and replacing most of the glass with sheet aluminium the full conversion has not added too much weight, tho i'm yet to weigh the vehicle fully laden.

I know the breaks are ok because I have overhauled all of these myself and am confident there fine.

I also believe that these buses had a crap rear diff ratio not sure what it is or what i should be looking for.

The engine does feel like it has more to give but seems like the auto box is changing up gears at low revs...is it possible to have this looked at..?

Think i'll get the injector pump looked at to start with.. thanks for the advise

Any more help would be good..

Cheers

ES

 

[lwbnick]

I own a 709d that I have converted into a motorhome with the intent to travel europe.. problem is it is very slow to the point of being dangerous..

Cummins B-Series would be a good swap, cheap durable engines, far better than any Mercedes engine durability wise, far more powerful.