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Discussion Starter #1
Has anyone tried or are using LPG injection with diesel on OM352. I have a 1317 bus converted to mobile home and am looking for a bit of extra power and economy. Any comment would be appreciated.
Thanks. Millex
 

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U1000Ag
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Hi, not on an OM352, but LPG on a mitsubishi 3.2D. Cost a small fortune to have installed - about $5000 and not worth it at that sort of pricing. Plus the supplier did not want to provide the software for finetuning - in spite of inititial promise. Company was Dieselgas and they used italian componentry.
The engine did perform better, but oil analysis done over an extended period - before and after - did not back up their claim of lower oil contamination. All in all, a serious waste of money.

I believe CNG gives similar performance improvements - problem is supply. Here in Oz LPG is reasonably well supplied but not so with CNG. If you have CNG piped to your home for home use, you can buy a special pump that will fill your tank overnight - and then it becomes quite econimical.

So, all depends on intitial installation cost and supply - decisions, decisions......
 

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1973 416 Doka, 1978 416 Doka, 1980 416 Doka..... Help me, I can't stop buying them!!!
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Talk to Brian Bills, he has CNG on his diesel pickup, and we are adding it to his 416L that will get a 352A motor as well. If it works out, I am going to add it to my 416 Doka as well. I am going to let Brian's truck be the test bed! If he gets the same great results like his pickup has, I will be adding it as well.
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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what is your current HP and have you done any modds to the stock setup?
 

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Discussion Starter #5
DokaTD, I am unsure of hp as dyno shop too far away. I renewed turbo to original specs. Fitted an air to water inter cooler and have just done 2500 Klm, engine felt lot stronger, I am happy with that. On the way I spoke to someone that suggested the LPG injection. He knew of it being done in several cases but not the OM 352. I am keen to try it so will keep asking questions. Any info no matter how insignificant might help.
Millex
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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If you have not adjusted your IP, you likely have free power just waiting to be released. Then add the LPG at a later date.
 

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I've mentioned this in the past when gas injection came up but I don't remember what the responses were.

There is only so much you can cram into a combustion cycle baring boost and even with boost it's still proportional, so to get more of the higher energy gas in the mixture you need to lower the diesel injection.

So unless you had some kind of on the fly or computer controlled variable injection method you are going to have to detune your injection pump to gain good results and then you are stuck with running with gas all the time or suffer worse performance that to begin with if you run out of or don't need to/want to run gas. And since it's not that easy to fill up unless you can do it at home you will need a pretty big tank, especially if you are going cross county.

Perhaps converting a gas motor to propane and boosting pressure to gain more power would be the way to go. Weren't you going to investigate boosting on your 404 KC?
 

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416L Doka and U1200
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Ok here we go,
This is not bs!
On a non computer controlled turbo diesel motor you will see up to a maximum of 30% increase in HP. Two kits I would look into are Marc Deluca in Chillicothe Ohio or The Diel kit from South America. I actually would parts from both kits.

My 2007 Duramax truck has a 100hp gain and diesel mileage with parts from both kits is 30mpg city and 58mpg highway at 69mph flat land with cruise control on. You have to watch you EGT if you are going to tow. I can't tow a heavy load with the truck in the hills with the current tune.
Diel kit is about $600.00 Marc's kit is about 1,200 plus a tank, lines and fittings
 

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When making or reading about claims of great mileage with gas, be sure to take into account the cost of the gas, or the BTU equivalency of the gas. 7.2 lbs of gas or almost 2 gallons of LPG (propane/butane) has the same btu content as 1 gallon of diesel.
When I was running LPG into my Hercules powered M37, I found that "real" mpg was about unchanged. Cost was slightly higher because propane purchased at the pump into a cylinder costs only slightly less per gallon as diesel, in other words almost twice as much per btu.
If there is an increase in diesel burning efficiency, it is in my opinion a second order effect.

Charlie
 

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Less BTUs per gallon? I thought thats the way it worked better because it had more BTUs per volume and therefore creates a bigger bang.

Hercules powered M37!? You didn't happen to buy that truck from a guy named Lyle Vanwort did you? Partially orange mottled truck comes to mind from many years ago.
 

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Discussion Starter #13
TKV000 vin number34520261692399 engine number. 34495160831954
Also I have not done any adjustment to IP. Sometime ago I did follow a thread here which show some end photos of the IP.when I checked,my IP had a one piece end plate so didn't go any further. If someone could explain what to do that would be great. I do have EGT gauge that runs max of 500 and a boost gauge that shows maximum of 10 psi.
 

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I guess I am lucky I have my own gas well. My range with CNG is 300 miles in the Duramax. I have 2 tanks a total of 18 GGE (gallon of gas equivalent).

I do not want anyone to think that I am saying that your mileage doubles in town. You are only replacing what you would use in diesel with CNG. But look at the price of CNG cost per GGE and in western Pa is under $2.00 per GGE Verses $3.76 for diesel. So by the time you buy the kit and the tank. I do just because I hate the raping we get at the pump (taxes)
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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TKV000 vin number34520261692399 engine number. 34495160831954
Also I have not done any adjustment to IP. Sometime ago I did follow a thread here which show some end photos of the IP.when I checked,my IP had a one piece end plate so didn't go any further. If someone could explain what to do that would be great. I do have EGT gauge that runs max of 500 and a boost gauge that shows maximum of 10 psi.
Your egts and boost are super low. This will yield lots of durability and longevity. But, you can increase your fuel and gain a lot of umph. You need to figure out which governor housing you have and then search here for the adjustment procedures. Both typical govs are very easy to work with. it would also be good to determine if you have piston oiling jets as well. This will dictate how far you can modd your current setup.
 

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I have a Diesel Gas system fitted to my 1996 Discovery Tdi - I got a quote fro it before the rebate system came in, and they honoured the quote. Mine cost $2000 - and I got a $1500 rebate so it was worth it - then the workshops decide to pocket the rebate themselves, and the prices shot up.

The extra power when it is switched on is really noticeable, and the gains are backed up by the dyno graphs I got from the workshop with the system. Fuel consumption is basically the same for the diesel - mainly because I use the extra power. I look at the LPG as a performance boost only - the cost of LPG over here is 1/2 the price of diesel and I only use 18lt of LPG for 90lt of diesel so the extra $15 per tank is worth it.


I'm still thinking of adding a system to my Mog - I got the space for a 80lt tank planned, but I will see how well the truck performs before I commit to it.
 

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Hi Iain - I'm bringing in a U1300L OM352. Given the low price of LPG here in Oz would you go for the LPG addition over a turbo? Given the overdrive and bigger tyres I'd like the extra grunt, not that fussed about the pure economics, don't want to do anything that will trash the motor.

Thanks - Craig
 

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85' U1300L Holset Turbo VA A/C, 66' Propane 404.1 rock mog, 1975 416 Doka, G500, Volvo C303
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Hi Iain - I'm bringing in a U1300L OM352. Given the low price of LPG here in Oz would you go for the LPG addition over a turbo? Given the overdrive and bigger tyres I'd like the extra grunt, not that fussed about the pure economics, don't want to do anything that will trash the motor.

Thanks - Craig
LPG won't do much for a Naturaly aspirated diesel.
 
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