Convert my FZJ80 to OM603 ? (1 Viewer)

[FJ80id10t]

I don't post much, but certainly do lurk.
My FZJ80 turned 315k recently and the front axle Birfields need a rebuild.
Other than what I consider normal oil consumption out of a 31 year old motor, and the valve stem seals need replacement, my 1FZFE engine runs OK, it's just not the peppiest of engines.
My though was, while I'm at it, swap the 1FZFE engine for a diesel from a '87 300TD that runs and drives well with about 200K miles. It's the OM603 turbo charged, and I can pick it up for $1500. This is one built after the early OM603 cracked head debacle.

Given that the Mercedes engine would get a rebuild while it's out, it would be that path, or rebuild my existing engine.
As far as experience, I've done engine rebuilds, engine swaps, tranny swaps, but no swaps that cross-over manufacturer engines.
I'm asking for your opinion -- whaddya think?

 

[FJ80id10t]

I passed on the OM603 and am picking up an OM617 in a week.

 

[mudgudgeon]

while I'm at it

That's one he'll of a "while I'm at it" if you're in there to redo birfs

I loved my hdj81 5speed, loads of torque and power with a tune up and some mods.

I find the fzj80 with 5 speed not far behind it in terms of driving experience. It's definitely not as powerful, but it's also bone stock.

 

[TheBussman]

I've been around both engines quite a bit, 603>617 any-day. With a 603 3.5 better yet I have a few sets of custom H beam rods on the way for those that will be for sale soon. (the rods are the weak link in the 3.5) if your looking for power neither engine in stock form will give you what you want. Although they can be upgraded easy enough (but so can the 1fz)

 

[Dougal]

I passed on the OM603 and am picking up an OM617 in a week.

I don't think the torque, power or efficiency of an OM617 will work in an 80.

 

[AirheadNut]

A stock OM617 will be pretty slow in an 80-series, but with an upgraded injection pump, bigger injectors and a modern turbo with intercooler it should be ok. A moderately tuned 617 can easily have equivalent or greater power to a stock 1HD-T. I had a W460 Mercedes G-class with an OM617, it had 7.5mm IP elements, .314 injector nozzles, a Holset HX30 putting out 18psi with no intercooler and a 3" exhaust. It ran great and made good power, but due to gearing it ran out of puff at about 70mph. Fuel economy was usually in the low teens, the vehicle weighed 5100lbs empty and ran on 37's. I wasn't easy on the throttle.

 

[Dougal]

A stock OM617 will be pretty slow in an 80-series, but with an upgraded injection pump, bigger injectors and a modern turbo with intercooler it should be ok. A moderately tuned 617 can easily have equivalent or greater power to a stock 1HD-T. I had a W460 Mercedes G-class with an OM617, it had 7.5mm IP elements, .314 injector nozzles, a Holset HX30 putting out 18psi with no intercooler and a 3" exhaust. It ran great and made good power, but due to gearing it ran out of puff at about 70mph. Fuel economy was usually in the low teens, the vehicle weighed 5100lbs empty and ran on 37's. I wasn't easy on the throttle.

View attachment 3598088

Makes perfect sense to upgrade an existing one in a G-wagen. But not so much to shoe-horn one into a bigger and heavier Toyota first.

Indirect injection diesels are on average 20% less efficient than direct injection. The most efficient petrol engines have similar fuel economy to the worst indirect injection diesels.

 

[AirheadNut]

Makes perfect sense to upgrade an existing one in a G-wagen. But not so much to shoe-horn one into a bigger and heavier Toyota first.

Indirect injection diesels are on average 20% less efficient than direct injection. The most efficient petrol engines have similar fuel economy to the worst indirect injection diesels.

I would tend to agree, the 617 doesn't seem like it would be a good fit for an 80-series. A 603 or 606 would definitely be preferable, but with the right efforts a 617 powered 80 would likely be quicker than a 3FE. The G was a pig in terms of weight, it was only a couple hundred pounds lighter than my HDJ81, with much bigger tires and worse aerodynamics I would expect fuel economy in a swap to be similar.

IMO one of the biggest downsides to the OM617 is its age: the newest engine out there is already approaching 40 years old and quality parts are getting harder to find. A fully rebuilt engine should be good to go for quite a while though. To get the best out of it I think a manual swap would be ideal. The 617 is no torque monster and likes to rev, having the ability to hold a particular gear and avoid churning a torque converter when pulling hills would be nice. I regularly cruised at 3600-3800rpm on the highway in the G-wagen, the engine was quite happy at those speeds but it could get pretty noisy.

 

[FJ80id10t]

All useful info -- thanks.
Finding a running, affordable 606.96x (still in a car) has been a chore. I've looked at two W210s but both want >$10K for the cars. I have also seen two W210s with the NA 606, and those are $5K or less.
I haven't even looked at pulled motors.
My intent is to take my time and upgrade injectors, pump and turbo as a part of this -- over time because the hobby mad money cash flow is a trickle ATM.
Granted I've looked at a bajillion threads on this, but any suggestions on a good manual trans to mate it with?

 

[TheBussman]

All useful info -- thanks.
Finding a running, affordable 606.96x (still in a car) has been a chore. I've looked at two W210s but both want >$10K for the cars. I have also seen two W210s with the NA 606, and those are $5K or less.
I haven't even looked at pulled motors.
My intent is to take my time and upgrade injectors, pump and turbo as a part of this -- over time because the hobby mad money cash flow is a trickle ATM.
Granted I've looked at a bajillion threads on this, but any suggestions on a good manual trans to mate it with?

best would be a tr4050 but you'll need some pricey adapters in front of and behind it. they're are much cheaper cars and engines out there. there is a high miles engine near me for $2000, I've seen a number of cars for sale around $3800 all turbo

 

[Dougal]

All useful info -- thanks.
Finding a running, affordable 606.96x (still in a car) has been a chore. I've looked at two W210s but both want >$10K for the cars. I have also seen two W210s with the NA 606, and those are $5K or less.
I haven't even looked at pulled motors.
My intent is to take my time and upgrade injectors, pump and turbo as a part of this -- over time because the hobby mad money cash flow is a trickle ATM.
Granted I've looked at a bajillion threads on this, but any suggestions on a good manual trans to mate it with?

What's your end goal and reason for swapping to diesel? This is starting to look like an incredibly expensive way to get very little difference in fuel economy or range.
A maxed out OM617 with better turbo still doesn't have the power or torque your 1FZ has. You need thousands in injection pump mods too and what's the reliability like with that much money in an OM617?

OM617 Performance Review

www.4btswaps.com

Expected Performance: Looks like all we can get from a stock pump (~63cc/1000shots) is around 300Nm and 110kw (220 ft-lbs and 150hp).

 

[FJ80id10t]

What's your end goal and reason for swapping to diesel? This is starting to look like an incredibly expensive way to get very little difference in fuel economy or range.
A maxed out OM617 with better turbo still doesn't have the power or torque your 1FZ has. You need thousands in injection pump mods too and what's the reliability like with that much money in an OM617?

LOL, because I'm a glutton for punishment. Like building wildcat rifles -- you get something cool in the end, but was it really worth all that hassle? So far, the answer has been a resounding YES.
On a more serious note, I discussed this with a buddy who has done multiple conversions -- a Cat BT4 in his old Rangie, a 606 to replace the v6 in his Sprinter RV. He said the 606 would be tits, and the most costly, a BT6 was too much weight for the LC, and that the 617 would be ideal with mods.
So far, my cost is just effort and gas -- I'm trading a load of firewood for the '82 300D. Personally I don't think I'd get that much more power in a 603, and really should go for a 606 if I want something with kick.
So while I'm collecting parts, please keep the insights and suggestions coming!

 

[Dougal]

LOL, because I'm a glutton for punishment. Like building wildcat rifles -- you get something cool in the end, but was it really worth all that hassle? So far, the answer has been a resounding YES.
On a more serious note, I discussed this with a buddy who has done multiple conversions -- a Cat BT4 in his old Rangie, a 606 to replace the v6 in his Sprinter RV. He said the 606 would be tits, and the most costly, a BT6 was too much weight for the LC, and that the 617 would be ideal with mods.
So far, my cost is just effort and gas -- I'm trading a load of firewood for the '82 300D. Personally I don't think I'd get that much more power in a 603, and really should go for a 606 if I want something with kick.
So while I'm collecting parts, please keep the insights and suggestions coming!

I've put the performance review link in the post above. 300Nm and 110kw is the limit for the stock injection pump. 220 ft-lb and 150hp.

 

[AirheadNut]

I'd argue the "ideal" part, but it will definitely work just fine for a daily driver. Getting the pump upgraded will pretty much be a necessity if you want any kind of performance out of it.

 

[mudgudgeon]

For all the work in sourcing parts, modifying pumps and turbo's, finding adapters and transmissions, why not just go all Toyota.
1hd-ft or 1hd-fte, h151 5 speed.
There's nothing unknown about these combos.
Everything is bolt in.
Spare parts are readily available.
Aftermarket support is solid (even if it's in Australia)
They are built for your 80, and well suited.
With the right tweaks along the way, they make plenty of power and torque.

Sounds like you'll spend as much dicking about with Mercedes stuff as you would to go oem Toyota.

 

[FJ80id10t]

Ha! Well, with all the advice given above, plus a thank you @Dougal for pointing me to your informative post on the OM617, I passed on th3 '82 300SD.
Went to look at a 603 today and the coolant pressurized with him attempting to start. I opened the overflow reservoir and it was filled with diesel soot. No bueno, so I walked away on that one. The search continues.