Ok, so, I do a bit more than beekeeping. We have an arrangement at our house that seems to work – Beloved ensures that the offspring are generally fed and cleanish and stuff, and I fix stuff – pretty much everything that gets busted. The amount of stuff that gets broken increases exponentially with each child. Possibly factorially – which is why many of my sentences to them end with a !. I have not yet repaired the dent in the plaster (drywall), or the broom which is in two pieces outside.
Lately, I have had to fix other stuff, busted through no evil device or scheme of my own offspring, but rather caused by some other muppet who has no business being near a tool. My Isuzu Bighorn (1996, 3.1 Turbo Diesel, for those who need to repair the same sort of thing) developed an exhaust leak, and failed its WOF (same as an MOT in England). I have replaced manifold gaskets on Holden engines before, and provided the studs are less than 25 years old (I mean the manifold studs – google will probably redirect some unusual traffic my way based on that sentence!), it generally takes about 1/2 hour. So, 2 and a half nightmarish days later, I finally have my WOF.
As it is so traumatic recalling, I will now put in a picture taken by my lad of a shooting trip we took a couple of days ago. He had some issues with aiming the camera, so missed the lineup of guns. The scenery was pretty epic though. It calms me to get out into the mountains.
The following details how to replace the exhaust manifold of a 1996 3.1 L Isuzu. If you don’t care about the details, just skim or skip, or read War and Peace instead (it is shorter).
- Remove the pipes on the intercooler – I used adjustable pliers for this, to squeeze the joiners together.
- Remove the intercooler – four 12 mm bolts. Don’t let the little rubber shock absorber pads drop down, they vanish in the blink of an eye. I found an extension bar with a snakey end piece was just the thing.
- Remove the battery – mainly for access and so you don’t incinerate your car by dropping a tool on the positive.
- Remove the exhaust to intake pipe (I don’t know what that thing does, possibly warms the fuel on cold days?), 2 bolts, 2 nuts. 12 or 13 mm. Will need a spanner rather than socket on one nut as the dipstick pipe gets in the way.
Up to here, I was going fine. This is where it started to get frustrating.
- Remove exhaust section – I went for two pieces – the connections are 4 nuts on the turbo, and two nuts on the exhaust flange. Plenty of WD40 or CRC may help. I didn’t need to, AS HALF OF THE NUTS WERE MISSING! The rest of the exhaust nuts were mix and match, some 14mm flange, 12mm flange, 5/8″. This was where I began to mentally curse the muppet who worked on it previous to my ownership. Thankfully, because the manifold gasket was so destroyed, there was no scouring of the flange metal.
- Remove turbo – to do this first remove two oil pipes and two water hoses. I used vice grips to gently squeeze the lower pipe, or you will lose your coolant.
- The top oil pipe, held on with a banjo, was easy – the lower one is a real pain – it is the long pipe thing going from under the turbo to the base of the engine. It is held in place by two 10mm bolts. I recommend a 3″ extension bar on a short socket driver. There is not much room, and unless you are 6’5″ or taller, you will need some sort of step. I used my chopping block, Pinus Radiata. Having 3 elbows on each arm also helps. There is a rubbery gasket on it, try not to lose. This procedure had me yelling the purple uglies something chronic. My helper, D, who was really good at giving me a 13 mm socket or 1/2″ driver or stuff, left at this point. This was probably wise, as a grown man with no skin on his arms or knuckles, leaning in an engine for a significant length of time while grunting and cursing on ribs bruised from leaning on the stuff in the engine bay, is not a pleasant picture.
- Mine had 3 13mm nuts, and one bolt, holding the turbo on.
- Gently remove the turbo.
- Remove heat shields from manifold – the right hand one has one nut into the manifold, and one at right angles to it, under the turbo attaching mount.
- Remove iron bracket from under the right hand of the manifold. Two nuts under the manifold outlet, and probably 2 (mine had one) bolts into the engine block.
- Remove 8 nuts from the manifold – this is where mine was interesting – the studs in mine had been replaced with cut down mild steel bolts.
Here is where the previous owner cursing really began – the top left bolt had broken, as it was probably over tightened. The reason it was over tightened would have been the bottom left bolt – which was only gently holding on by 2 threads, a special, cutdown bolt – as there was a snapped stud – STILL IN THE FRIGGIN ENGINE BLOCK. The muppet had just filled the hole, and over tightened the top bolt to compensate, RRRAAAGHHH!
A moment on the word compensate, I have somehow convinced my lads, who are always asking what different parts of cars are called, that the really excessively large big bore exhausts on average looking cars with fluffy dice and OOONTZ OONTZ bass speakers are called compensators. We all know what they are compensating for, don’t we (wink wink). It will be a dark day when my boys figure out what I mean.
With the manifold off I was more able to see what had been going on. It was time to remove the offending stud. I searched for about an hour for my center punch, which I haven’t used since we moved house – could be any where. By this time I needed counselling. Instead of a center punch, I used an old drill bit, as the metal is hard enough. I punched a hold fairly centrally in the broken stud and then began to drill it out. I used 3mm, 3.2, 3.5, 4.0, 4.5 mm drills. I could not use any bigger that that, as the 5mm drill bit was a half inch longer, and no longer could the drill fit in the engine bay. I had the option of cutting down drill bits, or attempting to use an easy-out (EZ-Out). An easy-out has a grippy left hand thread, which you wind in, then, as you keep winding it tightens and removes the offending broken bolt. UNLESS THE FRIGGIN THING SNAPS OFF IN THE HOLE!
At this point I admit, I did yell like a tortured Wookie, and threw the broken remains of the EZ-out somewhere. I may have kicked a few things too, things got a bit fuzzy. On doing some more googling, there are two main ways of removing a broken ezout. (I won’t even give the thing the dignity of capitals anymore.) It turns out that EZ-Outs are made from some of the hardest tool steels known to mankind. The first method involves mounting the housing in a mill and using a carbide end mill, or 2, or 3, to remove it – that required removing the engine block and carrying it to an engineering workshop – not gonna happen. The other involves using a center punch and hammer to break it up in -situ – again, not gonna happen as there is not enough room to swing a hammer in there, hammering an engine block is seldom a good idea, and I STILL DON’T KNOW WHERE MY PUNCH IS. One fellow stated that engineers he rang would suddenly disconnect when he mentioned broken ezouts. Others would laugh first, and then hang up. Other methods include burning it out with a gas torch, welding a nut to it, drilling tiny holes around the silly thing, all impractical for my situation.
I ended up purchasing a Dremel (Should have owned one years ago) and a carbide mill for it. I milled it out really slowly, on high speed, with light pressure. I recommend bunging up all visible holes, as there is a lot of very fine, extremely hard dust floating around. Just what engines love. Eventually, after perhaps an hour or two of intermittent drilling, there was a little bang, and chips of ezout came flying out of the hole, driven at 30000rpm by the Dremel. Eye protection is recommended as really, really important in the Dremel manual. I can see why.
After the ezout was out, I used the Dremel to widen the hole, until I thought it was pretty close to the hole. I did not want to stuff up the threads, or else it means precision drilling, retapping, and inserting a thread coil.
Then, I just needed to retap the thread, to clean up all the rusted in bolt. It is an M8x1.25 I think. Thankfully, our neighbour, Dazza, has a fully equipped workshop, and I was able to borrow a tap from him. From here on in, it all went smoothly enough.
- Clean up the area, place new gasket over the studs (oh, that’s right, it had bolts, not studs, which are apparently rare as hens teeth and cost an arm and a leg each. I chose high tensile M8 bolts instead, so had to insert a couple of bolts through the manifold and gasket, position on the engine, and get a few threads going. You only need three hands for this step.
- torque down the bolts to the correct amount. I don’t have a torque wrench, so went with the amount that seems to work on Holden manifolds.
- Insert everything else in reverse order.
The only other problem I had was replacing one nut on the turbo-manifold flange (top right). There was just not enough room and the SOB kept falling. In the end I used a 12mm ring spanner, circlip pliers to hold it, and my index finger. I lost one nut, lost forever between the manifold and gasket, probably to rattle for eternity. Thankfully, due to discovering the missing nuts in various places, I had purchased spares.
When started, all ran quietly, smoothly, and there was no way I could hold a rag over the exhaust – too much pressure, no leaks.
I now have a fresh WOF, and a quiet truck. Yay.
Oh, and my hive is fine.