'86-'94 Jeep Renault Alliance XJ\MJ Model 77, 78

Hi all - an old noob here - any XJ\MJ Diesels out there? Is there a dedicated section for these rarities on this board?

Purpose and scope of this post is reliable information and data on the Cherokees and Comanches with the Renault J8S 2.1L TurboDiesel engine - any input is appreciated, even negative owner-experiences - NO flame wars, please - I'll start off with my discoveries during the four days I've owned this one...............:compwork:

Just acquired an '86 XJ and am doing in-depth discovery even as I type - the '86 is a Renault 2.1L 126cuin 85hp Turbo Diesel, tilted ~15* to the left - has a small ~6" shock-absorber mounted between the chassis and a bracket on the lower right front of the engine (Diesel shudder, anyone?) - instrumentation is coolant temp, oil press, combo 15psi Boost\vacuum, and tachometer - Diesel Fuel Only, of course - preliminary findings indicate a Garret\AirResearch wastegated turbocharger - OHC engine is all aluminum, 2v head and block, replaceable cast-iron cylinder sleeves - crank-driven toothed rubber timing belt drives the camshaft and German-made Roosa Master IP (a Stanadyne Brand) - IP and injectors are mechanical - Bosch timed-glow system - Stanadyne fuel filter\manager with Fuel heater, W-I-F and Vacuum sensors - have not located a fuel lift pump, tho have not been long under the vehicle - Donaldson air filter housing - engine-driven diaphragm-type vacuum pump, for vacuum brake booster, cruise, and HVAC system, is mounted on the left side of the engine block - charge-air cooler behind the right headlite, ducted to area between lite and radiator - engine oil cooler between a\c condenser and grille - remote oil-filter assy on the right fender well, incl bypass valving and oil press switch, via neoprene rubber hoses - engine-coolant reservoir similar in shape, size, and position to KJ unit - v-belt driven clutched fan, CW rotation - CCV draws from the aluminum valve cover thru a rectangular thermo-plastic vapor-separator box to the 'charger inlet, precip box has a bottom drain connected to the oil pan (hmmmm, where have I seen that config?) - at 90kmi, 'charger inlet and cac hoses are not exceeding oily, as has been seen on the KJ, tho the Cherokee has been in storage since 1993 - Aisin Warner AX5 5sp manual trans - Girling hydraulic clutch setup - and, of course, the coil-sprung four trailing-link trackbar-located Dana straight front axle, minus the drive diff - easy change-over to 4wd, by subbing-in the Dana 30\44 drive front axle and adding the NP\NV xfer case, for the intrepid gear-head - as I earlier stated, application of care and thrill of discovery - more later..............

Later - found it, low driver's side behind the vacuum pump - vacuum pump is driven by a timing-belt driven intermediate shaft, which in turn drives a gear on a common shaft between the vac pump and engine oil pump - intermediate shaft also has a cam lobe at the rear to operate a diaphragm-type fuel lift pump, which, as we all know, is designed for pull-type service, pulling fuel from the rear-mounted fuel tank to the engine - more even later.............

Later: whups, my bad! What appeared to be the fuel pump from beneath the XJ was just a dirt-grease-grime distorted underside view of the vacuum pump - Stanadyne fuel-manager fuel outlet connects directly to the IP fuel inlet - if there is an auxiliary fuel lift pump it must be in the tank - so far, I've found only one wire to the tank, which would be the fuel level gauge - also, IP may be Bosch unit: OEM markings are difficult to read\decipher at this time - later..........

'05 KJ CRD Limited
Pricol EGT, Boost, Rail Pressure, Trans Temp
Inmotion SII; EDGE Trail
SEGR; Provent; Magnaflow;
Suncoast T\C, Transgo Tow'n'Go switch;
Cummins LP module, Fleetguard filter, Filterminder
2.5" Daystar f, OME r; Ranchos; K3199's, Al's lifted uppers
Rubicons, 2.55 Goodyears
Four in a row really makes it go

89gmctd said:

Hi all - an old noob here - any XJ\MJ Diesels out there? Is there a dedicated section for these rarities on this board?

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No, but there almost should be given how few are likely to still be running

Just acquired an '86 XJ and am doing in-depth discovery even as I type - the '86 is a Renault 2.1L 126cuin 120hp TurboDiesel, tilted ~15* to the left - has a small ~6" shock-absorber mounted between the chassis and a bracket on the lower right front of the engine (Diesel shudder, anyone?) - instrumentation is coolant temp, oil press, combo 15psi Boost\vacuum, and tachometer - Diesel Fuel Only, of course - preliminary findings indicate a Garret\AirResearch wastegated turbocharger - OHC engine is all aluminum, 2v head and block, replaceable cast-iron cylinder sleeves - crank-driven toothed rubber timing belt drives the camshaft and German-made Roosa Master IP (a Stanadyne Brand) - IP and injectors are mechanical - Bosch timed-glow system - Stanadyne fuel filter\manager with Fuel heater, W-I-F and Vacuum sensors - have not located a fuel lift pump, tho have not been long under the vehicle - Donaldson air filter housing - engine-driven diaphragm-type vacuum pump, for vacuum brake booster, cruise, and HVAC system, is mounted on the left side of the engine block - charge-air cooler behind the right headlite, ducted to area between lite and radiator - engine oil cooler between a\c condenser and grille - remote oil-filter assy on the right fender well, incl bypass valving and oil press switch, via neoprene rubber hoses - engine-coolant reservoir similar in shape, size, and position to KJ unit - v-belt driven clutched fan, CW rotation - CCV draws from the aluminum valve cover thru a rectangular thermo-plastic vapor-separator box to the 'charger inlet, precip box has a bottom drain connected to the oil pan (hmmmm, where have I seen that config?) - at 90kmi, 'charger inlet and cac hoses are not exceeding oily, as has been seen on the KJ, tho the Cherokee has been in storage since 1993 - B\W T5 5sp manual trans - Girling hydraulic clutch setup - and, of course, the coil-sprung four trailing-link trackbar-located Dana straight front axle, minus the drive diff - easy change-over to 4wd, by subbing-in the Dana 30\44 drive front axle and adding the NP\NV xfer case, for the intrepid gear-head - as I earlier stated, application of care and thrill of discovery - more later..............

Later - found it, low driver's side behind the vacuum pump - vacuum pump is driven by a timing-belt driven intermediate shaft, which in turn drives a gear on a common shaft between the vac pump and engine oil pump - intermediate shaft also has a cam lobe at the rear to operate a diaphragm-type fuel lift pump, which, as we all know, is designed for pull-type service, pulling fuel from the rear-mounted fuel tank to the engine - more even later.............

Later: whups, my bad! What appeared to be the fuel pump from beneath the XJ was just a dirt-grease-grime distorted underside view of the vacuum pump - Stanadyne fuel-manager fuel outlet connects directly to the IP fuel inlet - if there is an auxiliary fuel lift pump it must be in the tank - so far, I've found only one wire to the tank, which would be the fuel level gauge - also, IP may be Bosch unit: OEM markings are difficult to read\decipher at this time - later..........

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OK, here's what I can tell you about these engines. Note that this is based on my experience in Europe with them in mostly pre-1999 Renaults; I've only ever seen maybe two or three of these XJs in the flesh in the US and have only driven one.

The Renault 2.1TD is not a bad little engine, particularly for the time that it was in production - it powered a bajillion Renault Trafic vans as well as some passenger cars, and in some ways was better than comparable offerings from the competition. Having said that, there are three things you need to keep in mind with it:

The XJ was not the best application for it. Compare performance figures for the 2.1TD against the 2.5 gas engine and you'll see why. The 2.1TD gets better mileage, but in real-world usage against the 2.5 gas the tradeoffs in performance and capability are very noticeable.

The only other vehicle in the US to use this engine in any appreciable numbers was the Winnebago LeSharo / Itasca Phasar motorhome. My understanding is that there is one parts source for these motorhomes that has replacement parts for this engine in the US, but they're apparently it. It also says a lot that most of those motorhomes have long since been converted to Chrysler 3.3V6s, though I'd argue that that's down to parts availability rather than any shortcomings (other than power) on the 2.1TD's behalf. Essentially, you're on your own.

The timeframe that this engine comes from is interesting in terms of the history of diesel engines - it's from the period where diesel engineering started catching up to their gas counterparts performancewise, but it's still a far cry from modern diesels in that regard. From what I recall there is some aftermarket for them in Europe, but given the now-dwindling numbers of them in use even there your options may be limited. Don't know if this is a consideration for you or not, but thought it was worth mentioning.

Having said that: nice find I'd like to get my hands on one myself just for the oddball value.

One thing you may want to look into if it ever comes down to it: swapping the Renault 2.1TD for the 2.5TD with intercooler from a late Peugeot 505. The reason I mention all of this is that the intercooled Peugeot engine makes decent power (and a 505 weighs about the same as an XJ, so performance should be about comparable), but it's still possible to get Peugeot parts here, albeit not as easily as a decade or so ago. Then again, intercooling the Renault lump may also be an option. Or a VW TDi swap.

In any event, expect to become the de facto resident expert on regarding these models if you aren't already - in the seven years I've been hanging around here, you've just given the most in-depth overview of them that I've seen.

BTW: this engine was never fitted to the Alliance or Encore, and IIRC the largest-capacity diesel fitted to an R9 or R11 in Europe was about a 1.7 - at least, that's what I recall being in the farm van R11 I used to drive. Could be wrong, though; Irish-market cars were typically notoriously stripped-down compared to everywhere else up until about 15 years ago.

I'm rather jealous...

My only worries would be the timing belt (apparently pure unobtainium as casm noted, if you find a source for them buy several so you have spares) and the transmission. Don't know what other vehicles the T5 went into that had the NP231/207/209 cases in them, but you will have to scrounge up a 4wd tailshaft and case adapter to mate the transmission to the transfer case.

kastein said:

(apparently pure unobtainium as casm noted, if you find a source for them buy several so you have spares)

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Expand that to include any Renault parts. I can usually get Citröen stuff without too much trouble, Peugeot bits with moderate effort, and items for Renaults only if the phase of the moon is right and I make the appropriate blood sacrifices. It's a large part of the reason I gave up on owning Renaults here even as an enthusiast vehicle.

and the transmission. Don't know what other vehicles the T5 went into that had the NP231/207/209 cases in them, but you will have to scrounge up a 4wd tailshaft and case adapter to mate the transmission to the transfer case.

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I'm really drawing a blank on that one. But: as counter-intuitive and contrary to common sense as this is going to sound, you may want to check if the BA10/5 from an XJ would fit, or possibly the BA7/5 (IIRC) from a Peugeot 505.

The BA10/5 has a bad rep in XJs, but, similar to the 2.1TD, the XJ was just not the right application for it - at least when it was behind the 4.0. You'll be stuck with the BA's internal slave cylinder (yep, it sucks, went through that on my 505...), but should be reasonably reliable behind the 2.1TD. You'll want to double-check that the bellhousings will mate up, but it may be a possibility.

casm said:

Renaults only if the phase of the moon is right and I make the appropriate blood sacrifices. It's a large part of the reason I gave up on owning Renaults here even as an enthusiast vehicle.

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I concur, My first car was a 1966 Renault Dauphine, I did a full resto on it and it took a month just to get parts from France.

Thanks, guys - all very helpful, tho somewhat scary on the parts situation - I thought I had noticed, in my searching, that the Renault 2.1L was categorized with a 1.6L, 1.9L, and a later 2.5L for parts sharing\availability, but have not found much further info on that - the XJ 2.1L is 'cooled, but where the Peugeot 505 cac is long and thin, the XK 'cooler is short and thick, mounted in the area where a battery might reside, behind the passenger-side headlite - probably very suitable for the oem 8psig Boost limitation, but would need much expansion to handle 1Bar and higher Boost levels, particularly since it is not engine-fan drafted - pics of the piston crowns appear to suggest they could take increased pressure, but have not yet determined if the aluminum head is secured with 5 bolts per or 6 bolts per cylinder - if 6, I can be more aggressive with the mild upgrades - there is a dedicated piston-spray system in the crankcase for oil-cooling the crowns, and there is a quite large engine oil cooler mounted in front the a\c condenser, fed by 3/4"dia hosing, so that's promising

GM used the B\W T5 extensively in their 1500 and S10\S15 4wd trucks with the NP series xfer cases - the S10\15 front drive output was on the driver's-side, like the KJ\MJ - so there are output shafts and housings, adapters, and xfer case input gears to convert the T5 - the XJ main case is different than those others, where the bell housing attaches to become part of the front bulkhead of the case - the clutch slave cyl attaches to the outside of the bellhousing, indicating separate throwout bearing like the GM units - that could be problematical if the input shaft collar is aluminum rather than cast-iron, as the t\o bearing easily eats away at the aluminum sleeve as it slides back and forth, with resultant binding and loss of disengagement - note that this is experienced speculation, as I've not been into it at that depth - possibilities, probabilities, etc................

xjtrailrider said:

I concur, My first car was a 1966 Renault Dauphine, I did a full resto on it and it took a month just to get parts from France.

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Interesting choice for a first car; I approve They're not anything you'd call fast, but have a definite charm. Wouldn't mind a Caravelle or Floride if a decent one turned up at the right money.

89gmctd said:

I thought I had noticed, in my searching, that the Renault 2.1L was categorized with a 1.6L, 1.9L, and a later 2.5L for parts availability, but have not found much further info on that

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Be careful to double- and cross-check references when dealing with Renault engines, particularly from this period: it was made at a time when they were keen on sharing production costs with other manufacturers by building several engines in a 'family' arrangement. As an example (and if memory serves): the 2.1TD is considered to be part of the Douvrin family (named after the town it was built in), which includes both gas and diesel engines of varying capacities in inline-4 and V6 configurations.

However, not all versions of those engines are mutually-compatible, even if basic layouts and capacities are similar. Probably the best example of this is the PRV (Peugeot / Renault / Volvo) V6; you can pull one out of each of its respective namesake manufacturers' vehicles and play spot the incompatibility, both internally and externally. For this reason, it's very important to know exactly what you're dealing with in this context as well as which application it was intended for.

the XJ 2.1L is 'cooled, but where the Peugeot 505 cac is long and thin, the XK 'cooler is short and thick, mounted in the area where a battery might reside, behind the passenger-side headlite - probably very suitable for the oem 8psig Boost limitation, but would need much expansion to handle 1Bar and higher Boost levels, particularly since it is not engine-fan drafted - pics of the piston crowns appear to suggest they could take increased pressure, but have not yet determined if the aluminum head is secured with 5 bolts per or 6 bolts per cylinder - if 6, I can be more aggressive with the mild upgrades - there is a dedicated piston-spray system in the crankcase for oil-cooling the crowns, and there is a quite large engine oil cooler mounted in front the a\c condenser, fed by 3/4"dia hosing, so that's promising

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Pay attention to cooling on these, especially at higher boost pressures. My one overwhelming memory of them was that they'd run reliably pretty much forever when stock and serviced to requirements, but like to blow head gaskets if constantly pushed to their limits and/or neglected.

Yep - that radiator and fan seem awfully small

the 2.1 was an option as late as 1994 over here. I have one on 31"s that's going to get a 8.8" rear, lower geas and some 33" or 35"s eventually.
Stock 4.10 axles aren't quite deep enough for the 31's..

I might have a link for the JS8 (2.1) manual if you need it.

89gmctd said:

the '86 is a Renault 2.1L 126cuin 120hp TurboDiesel,

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120hp??? With turbo and intercooler the 2.1 only produces 87hp stock.
Did i miss something here?

Norwegian said:

the 2.1 was an option as late as 1994 over here.

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But only in LHD - the first year or so that the XJ was on sale in Ireland and the UK, we didn't get a diesel option. It wasn't until the VM 2.5TD hit that there was a diesel option in those markets.

Norwegian said:

120hp??? With turbo and intercooler the 2.1 only produces 87hp stock.
Did i miss something here?

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Evidently I did, too - that engine never went much over the 87bhp mark in the XJ, and I don't think it ever really went much higher than that in other vehicles either.

No - that's another my bad - saw several figures while searching for the power output, began to see most indicating ~85hp, but the original entry was posted, fait accompli - thus, to make scarce info easier to find I maintain all pertinent data in that first post, which I continually edit with ongoing updates - any interested reader will then get the whole feast in one fell swoop - can sorta tend to make the contributing posters look like idiots, but the scope is to get the info in one place and out there and useable - hope this method doesn't put anyone off, but this scarce documentation is needed, particularly from and for those international readers, where this Diesel is more prevalent - ever onward and upward.....................


Hmmmmm............seems that I've lost editing function on that post - how rude..................

89gmctd said:

I maintain all pertinent data in that first post, which I continually edit with ongoing updates

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Just FYI - the forum software only allows members to edit a post for the first 45 minutes after it's made. The time limit on the editing window may be different for non-members, but the same restriction applies. Once that window has elapsed, the post is set in stone in perpetuity; you cannot go back and edit it. Because of this, it helps to have everything verified in advance.

Yep - figgered as much - been forum member on various Diesel forums for over ten years - difficult to verify, all in one spot, data that just trickles in during on-going discovery - here in the later I can see misinfo in that post that downright begs for correction - f'rinstance, after severe cleaning-up, I can see that the trans is an AX5, not a B\W T5 - bummer on the misinfo, and double-bummer on having the weak-sister trans...........

At least it isn't a pugeot tranny! Though with 85bhp it might live longer. I can edit the original post to update if you want, unless someone else beats me to it.

Ok, that'll work - thanks
- change "120hp TurboDiesel" to "85hp Turbo Diesel"
- change "B\W T5 5sp" to "AX5 5sp"
- add "J8S" between Renault and 2.1L in the first line

TurboDiesel is correct for some marquees, but AMC\Jeep seems to have liked Turbo Diesel

Nobody liked the 85hp..............