Lessons Learned Rebuilding 5.0 V8 2012 LR4 Engine

DGAP

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What a great write up. I currently have an LR4 which had the the crossover pipe split down the seem and have been told by LR it’s a new engine or new car. I am currently tearing the engine apart to determine the extent of the damage. Can anyone recommended a machine shop or an engine supplier (or both) in the Savannah/Jacksonville area? I really want to get this British lady back on the road.
 

AGLR4

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I'm glad to see more people tackling this project. Thanks for posting these lessons. The more often this is done the greater the collective knowledge about this process which should make it much easier for those in the future. When I did mine a few months ago I could only find one good thread of someone rebuilding JLR 5.0 and that was in a Jag. Since then I've seen at least 2 or 3 others like you getting it done. Just more proof that it can be done. I don't think any of us will say it is easy, but I do think it is worth it.

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gsxr

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What a great write up. I currently have an LR4 which had the the crossover pipe split down the seem and have been told by LR it’s a new engine or new car. I am currently tearing the engine apart to determine the extent of the damage.
Why exactly is the dealer saying your engine is junk? Tearing it down yourself is a good start, btw.



Can anyone recommended a machine shop or an engine supplier (or both) in the Savannah/Jacksonville area? I really want to get this British lady back on the road.
You should post a new thread for the shop recommendation, not many people are going to see your post here.
 

johnnwalters

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Red Top Engine, thank you for being candid and helping us all learn from errors made. That's what makes this forum so good!
 

Red Top Engine

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What a great write up. I currently have an LR4 which had the the crossover pipe split down the seem and have been told by LR it’s a new engine or new car. I am currently tearing the engine apart to determine the extent of the damage. Can anyone recommended a machine shop or an engine supplier (or both) in the Savannah/Jacksonville area? I really want to get this British lady back on the road.

The crossover pipe is relatively easy to replace. Less the car was driven extensively while overheating and the heads are warped (and even that is not possible as it will shut itself off), I don't see the logic behind replacing the engine.
 

DGAP

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I have a question about Tappets. All of mine got knocked on the floor, needless to say I don't know where they go. They all look and fit the same, but do appear to have different part numbers. I really don't want to buy new one, is there a way to figure out where they came out of?
 

gsxr

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I have a question about Tappets. All of mine got knocked on the floor, needless to say I don't know where they go. They all look and fit the same, but do appear to have different part numbers. I really don't want to buy new one, is there a way to figure out where they came out of?
If you can post the part numbers, we may be able to figure it out via Microcat (the LR dealer parts catalog). Or look up the number and see if there is useful info on the interwebs.

It's not ideal to have a used tappet/follower moved to a different cam lobe, but if all the lobes and tappets have even wear and are generally in good condition, I think the risk of failure is pretty low. The only other option is buying all new ones ($$$$).

:help:
 

AGLR4

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I have a question about Tappets. All of mine got knocked on the floor, needless to say I don't know where they go. They all look and fit the same, but do appear to have different part numbers. I really don't want to buy new one, is there a way to figure out where they came out of?
Short answer = NO

Long answer: The intake side should not matter because those are hydraulically adjusted. It is best to put them back where they came from since they have worn in to a comfortable position, but ultimately they will probably all fit interchangeably and adjust correctly with oil pressure.

Your problem is going to be related to the exhaust side. These are not hydraulically adjusted so they must each be appropriate for the tolerance at their location. The measurement is on the inside for how thick each one is (see my first photo). If all of them measure the exact same (which would be highly unlikely) then the location wouldn't matter. Assuredly though, there are going to be several of different thicknesses, as even brand new from the factory the engine was not perfect at every valve.

The exhaust valve clearance is 0.25mm +/- only 0.02mm. This gives extremely small room for error. If you put a tappet too thick in then there will be no valve clearance and the valve will not fully close even at the lowest portion of the Cam lobe. Incomplete closure will allow the valve to burn quickly as it cannot transfer heat to the seat.

No one can tell you where they belong because no 2 engines are the same. You can figure it out though, it will just take time. Put them in and install the exhaust cam. Then use a feeler gauge to see if you are within spec. If not, do some math to figure out how much additional thickness you need where they are too loose or how much to take away where too tight and move them around until you get as close as you can.

To be honest, you may not want to use all of them anyway if you are rebuilding this engine. I reused as many as I could and still bought about 10 new ones.

Good luck, and let us know how it goes!
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greiswig

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To the OP: I had a love/hate relationship with my Unimog 416 Doka that sounds a little like this. Thank you for sharing your journey!
 

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