Un-doing a 88 Trooper II CrankShaft Bolt

Use an air impact gun. Set it for max torque. Turn on your compressor and let it build up to full and shut off, and set your line pressure gauge at

150 psi. Use an impact socket, not a regular socket. Do not use an extension. If necessary, take out the radiator to get more room. The bolt turns out counterclockwise, looking from the front of the engine. Put in a set of foam earplugs. Hold the impact gun tightly, make sure it's set to turn counterclockwise, and let it hammer... and hammer, and hammer away, until your compressor kicks in... then do it again, and again, and again.... it will come off. Been there, done that. Trust me, it works. r/ SPR

Thanks for the reply. Unfortunatly I do not have access to a air gun ): I will try my Impact Driver with the rght adapter on it.Just not to sure how well the breaker bar will stay in were the starter was. All I need to do is check that the work done preveously have the crank and cam shafts lined up corectly... Three times now the Head has blown... Two NeW Heads and this one has less than 500Kms on it. Just replaced the water pump only tohave the pump be faulty with the wrong impelar and lookslike the head gasket betwen 2+3 has gone. So far all the bolts I have had to undo for the work done by 4 other mechanics has been loose (less than 5lbs) Just at the intake common and head point.Ready to take then all off in one piece as my manual tells me. Do you recall where the CamShaft Sprocket should be with Cyc 1 @ TDC ? I have 1 @ TDC and the Rotor Pointing to #1 on Dist But the Notch on the CamShaft is 180 from the mark on the Head(Pointing Down) is this correct ! Did I miss something in the manual ?!

Regards..

Slowly becoming a Trooper II Expert.

Thomas, see my comments in your text...

Is it possible for you to rent one? I see them all the time in second-hand stores - just recently, I saw a very good Craftsman (Sears) model for $25. If not, can you borrow one from a friend?

I don't think that will work as well as this.... try reinstalling the starter, then using a very very stout breaker bar with a very good socket on it, hold the breaker bar against the frame, with the socket completely covering the balancer bolt head. Then have your wife/girlfriend/helper turn the key on and crank the engine ever so gently. As long as you haven't disassembled the timing belt (which I don't think you have), you should be ok. The goal is to use the starter to provide the turning force, whilst the breaker bar does the work of turning the bolt. I've done that before and it's worked. However, the air impact is the way to go, if you can.

Sad but true. You are your own best QA....

I distinctly remember the mark on the camshaft has to be pointing at the mark on the sheetmetal pointer, and the mark on the crank has to be pointing at it's index mark. If you are 180 out on the cam, then rotate the crank another turn. Remember, the crank turns 2 times for every one camshaft rotation, so if you're 180 out, then the crank needs to go around again. If I remember right, the distributer is driven off the camshaft... so it is matched to the cam.

I hope this helps. If need be, I'll go dig out my old Haynes manual for you... let me know. r/ Steve

Thomas, Isuzu sets the initial alignment with #4 cyl on TDC compression stroke, not #1, thus the confusion. If you rotate the crank 180 deg you should find proper alignment. Note that at this point the dist. rotor will be pointing at the #4 spark plug wire's contact in the dist. cap.

Regarding your crank bolt, I've used the breaker-bar-on-the-frame trick many times and it's always busted the bolt right loose. As you're looking at the engine, the breaker bar would be over to the right, or driver's side, resting solidly on the frame. You can also put a block of wood between the bar and frame if you want to cushion it. All you have to do is 'bump' the key and it should bust that bolt right loose.

When you're doing the gasket replacement, check block/head for straightness as a warped surface will cause problems. Check for proper placement of the dowel 'split' pins, one in front and one in back of the block. These locate the head and it'll jump around on the block if they're not in place. Given the 'high quality' repairs done to your rig so far, it's certainly possible they left them out!

Chase out the head bolt holes in the block with a 12MMx1.50 tap, this'll give consistent torques on the head bolts. Holes full of crud may not even tighten down fully and can cause a blown gasket.

Do use an Isuzu head gasket, not aftermarket, which are more prone to blowing than the factory item.

is a good source of new parts, as is Isuzu Guru Jerry Lemond in Dacula, Georgia. Jerry was a factory rep and knows these critters inside and out! Great guy to deal with, too. snipped-for-privacy@bellsouth.net

Re-torque the head after 500 and 1000 miles, then do it with every valve adjustment (10,000 mile intervals). You'll have to do the KM conversion, my brain ain't up to it tonite!!!

BTW there are several very active Isuzu groups on the 'net and you can search past posts for more detailed answers to your difficulties:

HTH............ed '90 Trooper LS 3.4 '89 Spacecab 4X4 2.6 '89 Trooper RS 2.6 '89 Trooper LS 3.1

Very Sorry about taking so long to get back to you Ed, Have had health issues with family members so the trooper has been on hold. Back to it this week.

Distributor Rotor is pointing to position #1 with the crankshaft pulley mark @TDC 0 when i pulled the head off. I will check alignment when i get the head back on.

I have given up on this side of the repair. I wanted to just see if every thing is lined up correctly, but if figure if I can not get that bolt off then the odds are it has not been messed with.

I have seen the two dowel pins still in the head, so they are there (: This is a new head with less than 5k on it.

I will have a close look and see how they look before the head goes on, picked up a tap and die set in anticipation of needing to do such a thing. !

This has become a ISSUE. I have a new headgasket from FEL-PRO that says its for; Honda Truck 4, 2.6l(4ze1) Eng. 1994-1997 Isuzu Truck 4, 2.6l(4ze1) Eng. 2559cc 1988-1997 Replaces No. 8-94174279-0

I had orderd and picked this up before i had taken the head off. Now when i got the head off i noticed that there was (three) more oil feeds on the gasket that came off the trooper than the NEW one. Back to the supplier i go with the OLD and NEW gasket in tow. I was told and shown by the parts person that the NEW one IS the right one. This makes me very concerned. My BLOCK has the THREE oil feeds, my HEAD has the THREE oil feeds, the Blown HEAD GASKET HAS the THREE oil feeds. So i drilled out the MISSING three oil feeds on the NEW gasket. Now i do a search of Isuzu parts on the net for the HEAD GASKET cause i am concerned with whats going on here. I find lot's of head gaskets for the trooper all with the THREE oil feeds MISSSING ! Another concern i have with the headgaskets; All the holes on the NEW and OLD gasket are smaller than the holes on the BLOCK and HEAD, varying from 1 or 2 mills to 12 mills in some places. When I removed the Blown OLD head gasket i enlarged all the holes to match the holes on the BLOCK and HEAD, WHY..... I thinking is this... If the Holes are smaller;

1)This will raise the PRESSURE at that Point. 2)Fluids flowing through the smaller holes will over time remove (disolve) the gasket until the hole is the right size. Contaminating the OIL and Coolant with the Gasket Material.

Maybe i am just being picky or the head gaskets both OLD and NEW are the WRONG ones. !

This is going to happen. Almost every Bolt I needed to undo to this point has been lose, no more than a gentle pull or push with the wrench.

Thanks again for all the help with the Trooper, I really do Appreciate your time and effort.

Jim AKA Thomas