Thread: Isuzu Engine Swops for Dummies

Originally Posted by 123rover50

Great thread. You guys sure can work

Damien drags his heels a bit, but the rest of us aren't so bad....

Originally Posted by mike_ie

....
I initially thought that I could cut and shut it, but it turns out that the R380 tranny tunnel is made from fibreglass for God-knows-what reason, so for now I've just pulled it out, and will figure out how to fix it later.
....

The 86 120 I bought came sans engine and gearbox (owner had transplanted them into a rangie). Because of the modifications to the fibre glass trans tunnel (and the KLR stickers on the windscreen and tray), I presumed the original LT85 gearbox had been swapped for an R380 at some stage.

The surround for the gear levers had been cut out of the fibre glass tunnel and a couple of pieces of aluminium sheet pop riveted to the tunnel and the surround pop riveted back in the new position.

Originally Posted by mike_ie

Damien drags his heels a bit, but the rest of us aren't so bad....

Hey, I just go to work to keep you in this lavish lifestyle you like to keep

Originally Posted by Bush65

The 86 120 I bought came sans engine and gearbox (owner had transplanted them into a rangie). Because of the modifications to the fibre glass trans tunnel (and the KLR stickers on the windscreen and tray), I presumed the original LT85 gearbox had been swapped for an R380 at some stage.

The surround for the gear levers had been cut out of the fibre glass tunnel and a couple of pieces of aluminium sheet pop riveted to the tunnel and the surround pop riveted back in the new position.

Yep, was discussing this with Steve and we pretty much came to the same conclusion - cut out the opening, with a lip to work with, move it forward the inch and a half or so it needs on a piece of aluminium, and rivet in place. Much less work for me than the other way round like your setup, as my tunnel is already plenty big to take the LT85...

I don't suppose anyone can grab me a photo or two of an LT85 transmission tunnel, particularly an overhead shot, and a measurement from bulkhead to the shifter opening, plus the dimensions of the opening itself??

Originally Posted by mike_ie

I don't suppose anyone can grab me a photo or two of an LT85 transmission tunnel, particularly an overhead shot, and a measurement from bulkhead to the shifter opening, plus the dimensions of the opening itself??

Sorry camera betteries need charging, however:

Opening is 16.5 cm W x 25 cm L - note these are ODs measured with the boot still on.

Firewall to front edge of opening = 6 cm. Note that was with carpet and fuse box in place. I tried to account for the carpet...

Next step is to get the big, bulky items into the engine bay, so that everything else can be worked in around them. First in is the new radiator and intercooler. Since I couldn't source an Isuzu radiator for decent money, I picked up a new County V8 radiator instead. Almost identical to the Isuzu radiator, just the inlet and outlet need to be swopped around and brazed back in, it's a straight fit into the Defender.



The intercooler is another matter though. At 602x300x85mm, it's not exactly small, and even though I have an extended front shroud, the intercooler still needs to sit inside the crossmember to that the intercooler inlet and outlet can pass through the wings.

Now seems like a good time to show the results of Steve's handiwork with the TIG...





...and here is where my intercooler needs to go - obviously not enough room.



Obvious solution is to move the radiator back further into the engine bay, but my Isuzu came with a viscous fan, the front face of which sits out 92mm from the front of the fan pulley, and already close enough to the radiator without running the risk of sending jagged bits of plastic through it.



Standard Isuzu fan sits 32mm closer to the engine, so in the end, I swapped mine out for a standard bolt-on fan. I'm sorry to lose the viscous fan, but I need the room, so....



A quick check with the measuring tape tells me that moving the radiator back 35mm will give me enough room to sit the intercoller back enough that the inlet and outlet will run through the wings. This still gives me 55mm between the fan and the radiator, which seems reasonable.



Radiator mounts set back 35mm...





County radiator seems to be 10mm shorter than the 300tdi rad/intercooler combo, so top radiator brackets need to be extended 35mm and cut down by 10mm accordingly.



Radiator and slam panel dropped in to test fit everything...





In order to run the intercooler lines, they need to run through the Defender wings. However, there isn't a whole lot of room to work with. Within the wing itself there are two baffles - one below the headlight, and one about 76mm lower, presumably to add rigidity and keep dirt out.

My intercooler has 2.5" inlets, which seems pretty standard. With silicon hose around it, that gives us a 76mm requirement. Nearest bigger holesaw I had was 85mm, which is perfect as it gives some breathing space for the intercooler lines. I don't usually like chucking out measurements because everyones needs are different, but the following measurements might come in handy for someone doing the same, as there really seems like there's no other place to run them.



I didn't want to go through the upper headlight baffle, but going through the lower baffle didn't seem to be a problem. First, drill and rivet the lower baffle to keep the holesaw from mangling it, then centre the holesaw 5mm below the keyhole cutout




Come up from underneath with the same holesaw, file the edges, and job done. As you can see, there's bugger all room. I'll run some trim around the edge of the cutout later to stop the edges from cutting the intercooler line.



Test fitting radiator 35mm further back...





...now mounting up the intercooler....







Plenty of room around the intercooler lines so hopefully no chafing...



I want to keep the factory aircon at some stage, so the aircon condenser will sit behind the extended shroud in front of the intercooler. I was planning on using the condenser that I had taken out, but after a chat with JC on the phone, who told me in no uncertain terms that the Defender condenser was a , I'll hold out for something better further down the line.



Sump welded up and painted...





The AH19066 air cleaner. Just a bit bigger than the stock 300tdi one... To modify it, the inlet will be removed and covered, and the dust outlet will be modified and used as the inlet.



The housing and twin filter elements...



Never fun taking a grinder to a spanking new piece of kit.... :/




more to come later....

The sump looks like a bought one!

I think that the D1 condenser is a lot better than the thing they put into the defender. Mine is a locally installed condenser, that together with the terrible placement of the evaporator in the passengers foot well make the whole thing very average.