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Willard
03-13-2007, 09:00 AM
Ok so i am really torn up on this. I am seriously thinking about putting a Diesel in my Rover. It would be a 5 cyl Mercedes diesel out of a 300d.
Or should i just rebuild my engine. the Rover has about 60K on the clock and the engine, like most old uncared for British engines, looks like it was dipped in oil, odd as it does not drip any and yes it has oil in it.
It is a 109 with the original 3 bearing (per the serial number) engine. I will be converting to 12 v either way so that is not an option to keep the 24V.

My only thing is as i do not have an overdrive this thing will move like a slug being a 109 with the full hard top.
I would prefer not putting a V8 into it as, well i just do not want a V8.

So any ideas, help, suggestions would be great.

solihull109
03-13-2007, 09:18 AM
Go diesel!, but why would it move like a slug....you're fitting a diesel and you already have 4.7.1 gears ....without overdrive, you'll redline the oil burner very early.....If you go diesel I would suggest an overdrive....not a Roverdrive from R.N, however, because that is a "fixed" gear, with an aux. overdrive( one that's not built in) you can shift in and out of it when needed, however, with the Roverdrive unit, you'll have a gap between third and your final drive....just my thoughts.:)

Willard
03-13-2007, 09:46 AM
Go diesel!, but why would it move like a slug....you're fitting a diesel and you already have 4.7.1 gears ....without overdrive, you'll redline the oil burner very early.....If you go diesel I would suggest an overdrive....not a Roverdrive from R.N, however, because that is a "fixed" gear, with an aux. overdrive( one that's not built in) you can shift in and out of it when needed, however, with the Roverdrive unit, you'll have a gap between third and your final drive....just my thoughts.:)


Thanks. I meant moving like a slug with the 2.25 not the diesel. That should be a little better. I will get an overdrive eventually.
I also agree with you on the Roverdrive, i have heard good and bad things about them, especially off road. people do not seem to like them very much. but thats is what i heard. i prefer the overdrive.

Tom109
03-13-2007, 11:12 AM
Solihull - are you refering to the RN high-ratio t-case? The Roverdrive is a high-quality (and expensive) OD unit for a Series, that fits more-or-less as the Fairey does (take grain of salt now). It's built by Rocky Mountain.

Willard - I run a (7:1) 2.25p in my 12V GS109. For the limited HP is has, I'm surpised how well it pulls. I do have an OD for the highway, but overall it does well except in the 48-55 range. Above/below that range it will hold well, even on moderate hills.

I'd love the increased range from an efficient diesel. But there are decent costs involved in the conversion if you fit an engine with more HP. The 200tdi is apparently the simplest to fit (not considering a LR NA diesel). Then you wonder about the transmission...

I'm going to keep my 2.25p for a while.

Tom P.

spechols
03-13-2007, 11:30 AM
I am replacing my 2.25 gas in my SIII 88 hardtop with a 2.5na diesel soon (I hope). It will have an overdrive (I hope it works). If all goes well in the next few weeks, I can let you know how the 2.5na diesel pulls at speed. My 2.25 gas works – I just want a diesel. Not sure what I will do with the 2.25 yet – first I want to get the diesel running in my SIII 88.

kirkt
03-13-2007, 12:05 PM
I suppose the answer to your question depends on the application. What do you intend to use the vehicle with the proposed engine configuration for? Are you considering the switch to diesel for performance reasons? Fuel economy reasons? Alternative fuel reasons? Etc.

As you are probably aware, the Merc conversion is an interesting and viable one for the Series Rover, at least the SWB one (Jim Young's SIII conversion is the epitome of the breed, IMHO). I am not sure how that conversion might work for a 109" truck, but someone has probably tried it. I know Jim was telling me about so guys in Canada tryin gto put a larger Merc diesel into a 6 cyl 109 SIII (i believe that was the conversion). Ask Jim himself about the viability - email him or post over at Guns and Rovers.

Diesel has many appealing features, depending upon the unit you intend to retrofit. The Merc unit is nice because the output is very similar to the Rover wih regard to the Rover driveline specs (rated bhp, torque, strength, etc.) and so little baseline modification is required to assure that the engine does not wind up the driveline and cause problems outside the typical failures associated with the Rover driveline and Rover petrol engine combo. Also, the removal of electrical issues and wading, low end torque, biodiesel and straight vegetable oil fuel alternatives are great. The alternative diesel power plants that are fit from the factory make things like engine mounts, suspension components, etc. fairly straightforward for a conversion.

I suppose the "cons" include moving things around and cutting and pasting chassis components, electrical and fuels systems to accomodate the new power plant. I suppose if you are going to convert to 12V from 24V you will already be doing a lot of electrical work anyway. The military dual tank system is a nice set up for running a two-tank petrodielsel straight-veggie-oil system - as long as you install a heater system for the veggie oil line. You will obviously be moving further away from Rover parts and availability, etc. But again, if you are moving from 24V-land, this is probably less of a big deal.

I would encourage you to contact Jim Young - he has dealt with 99% of all of these issues already and is super nice and willing to share his valuable expertise. He also manufactures kits for the Mercedes conversion (namely the adapter plate to couple the Merc to the Rover transmission). Look at the write up he has done on his conversion and then drop him a line. he is in CT and it may be worth a trip to meet with him and see his vehicle.

Good luck! I have wanted to to this conversion for a long time but have a perfectly good running 2.25 5-bearing Petrol in the lightweight, so I will have to wait, I suppose - unless you want to make an offer on my engine..... :-)

http://www.seriestrek.com/

will get you started.

Kirk

PS - @spechols - are you sure the n/a 2.5 LR diesel is a good replacement? There a re probably better alternatives, as what admittedly little I know about the LR n/a diesel is not real good.

KevinNY
03-13-2007, 01:27 PM
I'm going to a Perkins Prima Td in a month or 2, I'll let you know how it works out.

Willard
03-13-2007, 01:43 PM
Hi Kirt,

Funny you mention Jim, That is who got me thinking about this in the first place.
His adapter plate is interesting, i am just not sure it is worth it in the long run. fuel cost, engine life maybe, but if i rebuild my 2.25 i would get a new life out of it. After rebuilding Cruiser 3B diesel engine. I know the cost is high for these.
I know the rear diff on my Rover can handle this as it is a Salisbury Axle. I am more worried about the weight and the transmission/transfercase, again i can ask Jim on that.

For what i plan to use my Rover for, well that is a good question, Hitting that favorite fishing hole, the odd group outing, traveling to the west for some adventure. that type of thing.

Changing from 12-24 volt is no big deal for me and i think the cost of this in the long run is worth it. As i will be tearing apart the whole Rover anyways i am set to do just about anything.

You point of keeping it original as possible is a good one and one i want to do. Just the engine is my only concern and i figure it will cost about 1700 for the diesel conversion and 1200 for the engine rebuild (i will do that myself)
I love diesel engine, but maybe i will stick to the 2.25.

My other worry is if i move from Virginia to another state and as the engine has been altered it get rejected.

kirkt
03-13-2007, 02:06 PM
@willard - good luck either way.

@ kevin - the perkins will be interesting - can;t wait to see how that turns out!

kirk

pbmonk
03-16-2007, 11:46 PM
It must be in the water..... I'm just now investigating costs etc of putting a 2.5TD in my 109. I want more torque - I hope top speed is maintained (with a Fairy overdrive). But noise is a concern.

Peter