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What else to do while replacing the head gaskets

Old Sep 29, 2025 | 05:42 AM
  #1  
DiscoOslo's Avatar
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Three Wheeling
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From: Oslo, Norge
Default What else to do while replacing the head gaskets

Thanks to some help from this site, I know I have a bad head gasket (only a bad head gasket, I hope). I am thinking I will just order the Lucky 8 top-end rebuild kit to save the hassle of collecting all the parts here in Norway. While I am at it, I will put in a flowkooler water pump. What else would be good to do while I am in there? I have thought about the camshaft, lifters, etc., but I am not sure if it is worth it. Also, would it be wise to tear it down and make sure there are no cracks, etc, before buying everything?
The truck runs fine, there is very little coolant loss over time, but I have green dye coming down the front behind the AC pump and the tell-tale white cloud out of the tailpipe. I have EU control due in a few months, and I doubt it will pass as is, so I need to stop stalling and just do it.
 
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Old Sep 29, 2025 | 06:54 AM
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skim the heads, valve job, new hoses everywhere as needed, plugs, wires, coil packs depending on age
 
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Old Sep 29, 2025 | 09:12 AM
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Relocate ignition coils ?
 
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Old Sep 29, 2025 | 09:42 AM
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Of course there’s a possibility of a cracked block, but I doubt that it’s very likely. It’s probably just the HG’s. Personally, I would order the parts and then disassemble it.
 
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Old Sep 29, 2025 | 10:39 AM
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When I did my heads I remember the "kit" was missing some items. Intake gasket and the o-ring that goes on the coolant pipe. ARP head bolts incase you need to break it down again. X2 on resurfacing the heads and a valve job/hoses. I also took the opportunity to change the timing chain and oil pump gears / reseal the front cover. Fuel injectors could be sent out and rebuilt. I used these guys (www.mrinjector.us)
 
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Old Sep 29, 2025 | 10:46 AM
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Richard Gallant's Avatar
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Check your wiring harness and re-wrap and re-cover as required. Most of the wire wrap will be rotten. AVOID soy based products the rats and squirrels love that stuff.
 
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Old Sep 29, 2025 | 02:24 PM
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Extinct's Avatar
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Several good recommendations from the group I will second:

1. Wire wrap.
2. If SAI, convert to flex hoses
3. If you are going to run the cooling system pressurized going forward (I do not recommend: https://extinctmotorsports.com/the-e...-min-read/)and they have never been replaced then a good time to replace the heater hoses.

A couple of other points:
1. I don't recommend the studs, write up here: https://landroverforums.com/forum/di...92/#post786998
2. I don't skim the heads if they are flat (normally they are flat unless severely overheated), less risk of a machine show screwing up the job (it happens). Same with the valve job (BTW, my three personal trucks all have over 220k, I restore and sell the low mileage ones).
3. I have a truck in the fleet currently with the crower cam in a 4.6, I cannot feel nor measure any significant power improvement. I tow, drive mountains, etc. Three with 4.0, two with 4.6 currently. IMHO not worth the money and break-in hassle.
4. Injector o-rings sometimes give trouble on very high mileage trucks, you can change those if you like. Injectors almost never go bad, I think I might have had one bad injector in 25+ trucks.
5. I would do the exhaust gaskets with these : https://a.co/d/g87U9T0 and these: https://extinctmotorsports.com/exhaust-studs
6. PCV mod if you have not already done it.
7. I would replace the throttle body heater plate with the billet one here: https://www.sportscarcentre.ca/MGM000010K Factory are known to warp and leak. Also replace the hard lines with ATF hoses.
8. PS pump?
9. I don't recommend timing chain, gears, nor oil pump if yours are fine. Replacement parts quality is questionable at this point and if your mileage is reasonable the probability yours are worn out is very low.
10. I like to wrap the AC hoses in foil tape as the factory shielding is sometimes in bad shape.
11. Fan clutch depending on age.
12. Consider idler pulleys, at a minimum plan to check bearings.

Feel free to ask if you have questions on the list.
 
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Old Sep 29, 2025 | 04:14 PM
  #8  
keninnc's Avatar
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From: Charlotte, NC
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Replace heater hoses.

1. They are not expensive
2. They get in the way putting the heads back on and tightening up the head bolts.

Remove them during disassembly makes the job easier.

 
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Old Sep 29, 2025 | 06:14 PM
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The above are all good ideas. Extinct has a lot of experience on these vehicles so his opinion is worth a lot, but I would disagree on the timing chain. They do stretch and rob power due to the valve timing going out of its ideal range. It is very unlikely to ever fail catastrophically though. I agree with everything else (including don’t replace the timing gears.
 
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Old Sep 29, 2025 | 09:38 PM
  #10  
whowa004's Avatar
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From: Denver, CO
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I did see TWS has a pricy timing gears that they look to make themselves? or someone other than poor chinese castings at least. So if your factory ones are totally shot then that might be an option. Can confirm the replacement gears from AB or RN or L8 are crap, reused stock gears with new chain on both my discos when I rebuilt them.
 
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