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Discussion Starter #1
There's an early thread discussing the relative shittiness of the existing motor in my RRC. Following that discovery I was leaning towards swapping a disco drivetrain into the truck when an opportunity arose to pick up a 4.6 that had been built with a crower 229, new lifters and a cloyes chain and converted to a V belt setup. It also has a retuned ECU to take advantage of the motor while remaining OBD1. The only issue: PO got water into #8 after 5K miles. He ran it after draining it to get home and apparently it suffered a high RPM vibration but was still a runner. Deciding that having neither money nor time, this sounded like a good opportunity to learn how to rebuild a motor.

Upon receiving the motor, a compression test showed the following:
1 -- 180
3 -- 180
5 -- 185
7 -- 190
2 -- 190
4 -- 192
6 -- 182
8 -- 160

So I think we've found the culprit. Popular opinion is that it likely has a bent rod on 8, I've sourced a good piston and rod to replace it. I've now torn it down and it's now the front cover and accessories, block, and heads left. Heads are going to be rebuilt locally or sourced from Tillery. Intake, valve covers are soaking and the Headman headers are painted and ready to go on.

My question is this: what should I look for on the cam, lifters and rods before I pull the heads and everything is intact? The wear (as far as I can tell) on the cam looks diminimis and is even. Next step is, I believe, to pull the pan and investigate #8 rod to look for damage.

Advice is more than welcome here.

Thanks,
Tony
 

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Looks very clean and from what I can see of the cam, not much wear. If it were me and the heads were that clean indicating not long since a rebuild, I would't worry with them except for a close inspection especially around #8. Look for a blown head gasket, broken ring(s) on #8 cylinder and scoring in the cylinder. A bent rod may not be readily visible but I would replace it anyway along with rod bearing and bolts. If it had good oil pressure before tear-down and there was nothing else found indicating the need for further work, I would just put it all back together with new seals and gaskets unless you want to go crazy and have the engine professionally balanced etc. You will love the 4.6
 

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Since you have it mostly apart, i'd pop for some machine shop time if it were me. Have the block pressure tested, miked, and tanked. I'd have the bores lightly honed and do new rings all around. New bearings while I'm at it. Only a few hundred bux worth and a huge life extending procedure for the lump.
 

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Discussion Starter #4
Attached is a picture of one of the heads, I think it's likely well worth having these cleaned up a bit. As I pop the heads (likely later this week), beyond a blown head gasket, would issues such as a slipped liner be obvious?

Bill, I'm trying to avoid tearing this thing all the way down so I don't wind up even more over my head, but I'll certainly consider your thoughts, thanks for that.

With any luck the new transmission and LT230 will be here in the next few weeks to go behind this thing as well.
 

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Tony,
Are the heads the type with two rows of head bolts or three ? On a 4.6 block the block will only have two rows of holes. I ask because early heads have three rows of holes and later only two. The three row heads were designed for the thin metal head gaskets and have a taller deck height. The later heads are designed for composite gaskets and have a lower deck height. You loose a bit of cr if you use the early heads. Those look pretty grungy.
 

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Discussion Starter #6
2 rows, I believe them to be the original, un-rebuilt, heads to the motor, the serial number ties to a P38.
 

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Hot tanking the heads, new valve guide seals, and three angle valve job will go along way to freshening her up.
Dont think Will T is still in the Rover business, last I saw him he told me he had his building sold and was going to manage a band full time.
 

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Discussion Starter #8
Dear god those head bolts are on there. Any tricks to loosening them before I round a bolt?
 

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Dear god those head bolts are on there. Any tricks to loosening them before I round a bolt?
Tap em with a ball peen in the center and use a long breaker bar with the right size socket. They are stretch bolts so yeah they hold pretty good until you over heat one of these.
The bolts are supposed to be single use but I'll let others advise on that.
 

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Discussion Starter #10
I'll give that a try, thanks.

Oh, and as recently as 2 days ago I was exchanging emails with Will on getting both new and used parts, so I believe he's still in the game.
 

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6 point socket and 2 foot breaker bar. It should be impossible to round the head of the bolts. They will be very tight. Use new bolts. Read the genuine workshop manual.....
 

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Discussion Starter #12
looks like I'll need to lock the engine stand in place as I'm moving it rather than the bolts. 5/8" seems a bit more snug. I'll break out the 2' cheater on 1/2" drive and a hi-lift handle and see what happens (after a double bowl of wheaties).
 

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A 3/4" impact will move them nicely too.
 

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I put a 4 foot cheater on my breaker bar and got them off. I was sure I was going to break one, but didn't.

Wait until you put them back on... For what it's worth, use new bolts, everyone says use new, and for the money, just do it. That'll save you searching the threads at least for recommendations. There are differing opinions on replacing with studs as well...
 

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Buy the stud kit. It's just so much better than bolts.
 

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Discussion Starter #16
I tried briefly to put my 3/4" impact on it (with my pancake compressor, I know . . .) and the head bolts laughed at it.
 

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When you get to the install stage be sure to chase all of those threads and clear the holes prior to fitting those new head bolts. I like studs but getting a head off after the engine is back in place can be a challenge.
 

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Since you have it on a stand already, you could rotate it and raise or lower so you can use more of your body weight on that breaker bar.
 

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Helps to have somebody holding the block. You can always use the hoist to take some of the weight and stabilize it that way. Worst case you can take the engine off the stand and lay it on one of the many extra tires in your garage. Also if they are hex head I don't think those are the stretch bolts. Those should all be 12 point IIRC.
Yeah those heads need to be cleaned up good. Thought this thing only had 5k on a rebuild. Guess it was really just the cam and lifters and the 3.9 stuff getting bolted on. So much for truth in advertising.

I wouldn't do the studs.
 
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