# Engine swap ~ pulling a gas, installing a diesel



## Melensdad

Just curious about the practicality of doing something that might be fun.

But it is WAY OVER MY HEAD mechanically so I'd need to find a shop that could actually do this.

I'm giving some serious thought to buying an older SUV type vehicle and having the gas engine swapped for a diesel engine.  At the same time I'd have the interior modernized a bit and basically bring the vehicle up to more modern standards.

High on my list of choices of vehicles are a 1980's (or somewhat newer) Mercedes G-class "g-wagon" and a similar vintage Toyota FJ.  Also possible would be an older Land Rover.

My engine of choice would be a Mercedes 320 diesel for the G-class or the FJ, but I'd probably find a diesel Rover engine for the Land Rover since I know those conversions have been done many times.

My question is, how feasible is this project or is it just a huge money pit?


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## muleman RIP

You will most likely need to beef up the front suspension to take the extra weight. As long as you stay pre85 you should not encounter all the sensor BS that modern computers like to read to let a vehicle operate. You will need a real good shop to make it something you will like long term.


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## sleeper

You should check your State's Emissions laws to make sure such a swap is legal for the combination you're considering. Some states may require a re-constructed title for such a swap depending on the year of the vehicle in question. Other states may not allow it at all. 

Good Luck if you decide to go ahead with it. It's a good project if you can locate the donors and the right wrench turner.


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## Melensdad

Indiana will allow it.  But there are laws that need to be followed.  

I'm curious what the real pitfalls would be.  Seems like a no brainer in terms of longevity, efficiency, flexibility, etc.  If it can be done right.  

How do I find a shop that can do this?  Internet searches are not turning up much information (other than for the Land Rover swaps because those are common).


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## Cowboy

Melensdad said:


> Indiana will allow it. But there are laws that need to be followed.
> 
> I'm curious what the real pitfalls would be. Seems like a no brainer in terms of longevity, efficiency, flexibility, etc. If it can be done right.
> 
> How do I find a shop that can do this? Internet searches are not turning up much information (other than for the Land Rover swaps because those are common).


 Your best bet would be a good reputable custom rod shop MD that does all of their own fab work in house they would have the knowledge of all that needs to be done to make it not only right but safe & up to date for ease of maintenece down the road . 

  You might also find someone that works at one that would be willing to take on the job at home on the side . Just a thought .


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## DaveNay

You could always contact these guys and see if you can get it done as one of their projects....

http://searchandrestoretv.com/


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## bczoom

I know it wouldn't be as fun, but if you want such a vehicle, why not just buy a diesel G-wagon?  They've had diesel power plants for most of their history.  It'll probably be a gray-market vehicle so you just need to confirm the emission changes were performed.


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## Melensdad

Finding a diesel G Wagon in the USA is very very difficult.


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## waybomb

Them G wagons are the shit!. There's an ex-mil diesel on ebay in PA now : http://cgi.ebay.com/ebaymotors/Merc...8126545?pt=US_Cars_Trucks&hash=item33659d1951

Now, when taking a say a 350ci chevy gas engine out, and putting in, say, a C15 cat engine, you can expect to tear up transmissions, driveshafts, and differentials quite regularly and with ease. Might make for some good YouTube fodder though.

Watch the torque ratings, not the hp ratings. And you will need different differential gearing unless you get something like a high speed yanmar engine.


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## Av8r3400

Bob, here is a better idea for you, I was (and still am) considering this one.

Locate an older ('74 - 91) GM Blazer or Suburban.  Pull the gasoline or (crappy 6.2) diesel and replace it with a Cummins BT4, 3.9L 4-cylinder diesel.  These can be had with an intercooled turbo setup that makes good power and will provide ~35 mpg to a vehicle as listed above on the highway.

Combine this motor with a 5-speed new process transmission and transfer case (if you want 4wd) and it will be durable in the extreme.

All of the parts needed for this are easy to come by here in the us and will be easily worked on by any competent diesel mechanic, unlike the Mercedes or Toyota units which are very, very uncommon in the US.

Most of the conversions like this start with a surplus "bread van" as the engine donor.  These Grumman vans were converted from gas to diesel on mass years ago and are now easy to come by on the 'surplus' market.


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## Melensdad

I currently own a Bread Van with a diesel engine.  Mid 80s vintage but the engine is strong and reliable.


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## Av8r3400

Cummins 4-cylinder with a GM T400 3-speed auto trans?

Some of the more popular conversions set the engine at an angle to make for turbo clearance on the doghouse.  

Is this what you have?


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## Melensdad

I dunno.  Its a GMC bread truck.  I bought it so I could paint it many colors to piss off the town of Schererville and get around a sign ordinance.  The fact that it ran well was just a huge bonus.  Its been sitting in the back of one of the stores for the past 2 years.


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## Av8r3400

That is probably what it is.  Now you are well on the way...


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## Snowtrac Nome

if it's an inline 4 it would be a 4b but alot of gmc step vans also came with a 6.2 diesel which isn't a bad engine it's just not the work engine the 6-b is 6.2' are reliable and start quite easy the stanadine db-2 fuel pump was the weak part of the package they are good only for about 60 k miles than need to be rebuilt the 6.2 with pump adjustments and advanced timing is capable of 175 hp and the engine will fit any place you can put in a big block because of the fact it's natural asperated it will require a larger cooling system but they will do 20 plus mpg in a 1 ton truck loaded or empty with proper throttle management i have gotten mine up to around 25 mpg


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## Av8r3400

Here is a real good source for 4BT conversions.

The Detroit 6.2 is a fair motor.  175 hp without a turbo will go through a LOT of fuel and push that motor well beyond the 110-120 it was designed for.

The P7100 injected 4BT is well capable of 200 reliable, efficient horsepower, weighs near the same as a bigblock gas motor with similar torque numbers, but easily double the economy.


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## Snowtrac Nome

mine still did 20 plus but i dont drive over 40 up here it's not a comercial engine but for a basic transportation rig it's not a bad unit cheap to buy and cheap to run pulling a 5th wheel trailer i would expect a drop in economy when using all 175 hp


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## RNE228

Have an acquaintance that that converted a 80's Chevy 1-ton dually crewcab from  gas to Cummins 12v. From what I gathered, the biggest issue was rebuilding the radiator support and moving air conditioning stuff around. The engine is long, so it was a decision between messing with the radiator, air conditioning, and intercooler, or rebuilding the firewall. 

The 12v is cranked up a bit too; it is a cool sounding truck!


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## Adillo303

Bob,

You can get in tough with Diesel Transmission Technology or ATS Diesel Performance they make diesel performance products, especially transmissions. 

I would say +1 to the Cummins idea. Either of these folks can steer you to a shop that can do the work as they both have dealer networks. 

I have owned tow Dodge / Cumins trucks (Bigger engine that you are looking at) Cummins is generally recognized as a great motor.


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## ben2go

www.4btswaps.com all kinds of swaps-look for Tenessee diesel on here-good info and good guy to deal with
www.superturbodiesel.com for Mercedes
www.dieselbombers.com

I am doing a Mercedes OM617 inline 5 super turbo diesel in my 2001 Ford Ranger.I am considering the same engine or the inline 6 OM606 for my 1990 Mercury Blue Max Cougar.It is feasible and if done correctly will improve performance and fuel mileage.I know guys that use Cummins 4bt in their older Chevys and get into the 20mpg range.


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## waybomb

I have a lot of experience with a 617 Turbo. Some pointers, some learned the hard way.....

Keep the valves adjusted. It is easy with the correctly bent wrenches you can find on ebay cheap. Before winter and before summer, every year.

These are old technology engines, but no reason you can't get 500,000 without any internal work other than a timing chain {AND GUIDES!} every 150k or so (you'll need the chain tool, again, ebay).

Glow plugs and relay, if you are in cold climates, just change them every year for a trouble-free winter.

If north of I80, I would install either an OEM Mercedes block heater that screws into the screw-type freeze plug, or, if you way north, a 1500 watt zero-start and a full voltage timer at the house outlet to energize the heater about an hour or so before you get up in the am. 

I also learned to use a wrap-around battery heater. Keep the battery warm, and you'll have all the cranking power you'll need, even at -20f. (That's the worst I ever experienced, but I'm sure it could go lower)

Injectors- save yourself headaches and have them rebuilt every 100k or get exchange units.

Oil - Delo 400 or Rotella T. 5000 mile interval ok if most is highway. If all in town, maybe 3000. Use premium oil filters (mann).

And if you want a bit more boost, drill a 1/16 hole in the reference line to the ALDA on the injection pump.

OEM parts, cheap, at buymbparts.biz. Deal with Rusty on the phone.

Technical advice, go to the diesel section on the forum at peachparts.com.


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## snowtrac jim

hello all.i have had land rovers for 20 years done lots off engine swops.have six of the things [thay breed] .i think over 25 years old ones are emishions exempt in us.200 tdi good engine 30 mpg .111bhp but best is aV8 on lpg .there easy to work on[ built by hand] and have no computors.pics of land rover 110 with discovery 200tdi was petrol. and a 1963 l/r 109 with 60 bhp n/a 2.25 .my next 200tdi candidate.


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## ben2go

snowtrac jim said:


> hello all.i have had land rovers for 20 years done lots off engine swops.have six of the things [thay breed] .i think over 25 years old ones are emishions exempt in us.200 tdi good engine 30 mpg .111bhp but best is aV8 on lpg .there easy to work on[ built by hand] and have no computors.pics of land rover 110 with discovery 200tdi was petrol. and a 1963 l/r 109 with 60 bhp n/a 2.25 .my next 200tdi candidate.




How did the TDI pull that Rover around?I considered one for my Ranger but they're made to pull around a 3500lb car,a not a 4000lb truck with a 3500lb loaded trailer.


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## Av8r3400

(I don't think that's a VW TDi motor, but a Rover TDI.  I could be wrong, though...)


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## ben2go

Av8r3400 said:


> (I don't think that's a VW TDi motor, but a Rover TDI.  I could be wrong, though...)



It's kind of hard to see on my puter.


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## snowtrac jim

hello ben. the rover 200 tdi was fited as standerd in late range rover classics.my engines are ex L/R discovery which have the same running gear as rangie. disco's are all rotten so cheep. aprox £500 .fit engine and gearbox rad and intercooler.this is a nut and bolt job more time than diffecult. manule better for towing .my 200.000 mile disco still dose 95mph and 30mpg at 70ish mph. jim.


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## Av8r3400

Boy, it would be nice if we could get diesel vehicles like this in the US.

(Thank the misguided ecco-nazis and liberals.)


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