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Left pistons and connecting rods on the right side...

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  #11  
Old 10-01-2014, 10:20 AM
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I've never had one of these engines apart but can the engine be inverted and the pistons and rods pulled out through the sump?
 
  #12  
Old 10-01-2014, 10:20 AM
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My motor is running good with the same gaskets and I pulled the heads before firing. I used arp studs and tossed the stretch bolts. Plus I bumped up the compression by shaving the heads .60 thousands. 7 months daily in hot bumper to bumper traffic. No issues. I talked to many engine builders about this also. Some said no but they were higher paid shops who will replace anything ( money is no issue). The other shops said its ok and they done it many times with no issues. If you fired up the motor then change. The heads and block have expanded and shifted and have crushed the gasket further.
 
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Old 10-01-2014, 10:21 AM
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i would just replace them for peace of mind. would hate to have to tear it all down again.
 
  #14  
Old 10-01-2014, 11:04 AM
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Originally Posted by Richard Moss
I've never had one of these engines apart but can the engine be inverted and the pistons and rods pulled out through the sump?
Yes, that's the other option. But on some engines, that requires a bearing replacement. I don't know if that's the case on these engines or not so I can't say for sure.

*Edit*
Then again, if the piston ring compressor cannot fully seat against the bottom of the bore, this may not be a viable option.
 
  #15  
Old 10-01-2014, 12:06 PM
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silly question; but did you check to see if the holes in the bearings line up with the holes in the rods. I'm just wondering if the rods are in backwards do the supply ports still line up? if not no oil to the wrist pins, rings or piston.
 

Last edited by drowssap; 10-01-2014 at 12:45 PM.
  #16  
Old 10-01-2014, 12:59 PM
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Originally Posted by drowssap
silly question; but did you check to see if the holes in the bearings line up with the holes in the rods. I'm just wondering if the rods are in backwards do the supply's ports still line up?
I think this^ would be the greatest determiner of whether the engine can be ran as it is or not. I know the bearings are offset as seen in this poorly sketched diagram:


The pistons and con rods are all balanced, so balancing isn't an issue.

And the issue with an offset on the pistons is nullified because the arrows on the pistons are all facing toward the front of the engine, so the offset would be identical regardless of the connecting rods.

Here's more detail given to show what I did:



And this is what RAVE says:


And the orientation that RAVE directs:



So, the real question in my mind is if the offset of the bearings in the connecting rods puts the pairs of bearings close together or far apart, and if the oil hole would be aligned in any specific way. I'll check that this evening because I can, or if someone else knows, please share!
 
  #17  
Old 10-01-2014, 03:37 PM
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Might effect the thrust bearing ???? also
Originally Posted by RSPTex
I think this^ would be the greatest determiner of whether the engine can be ran as it is or not. I know the bearings are offset as seen in this poorly sketched diagram:


The pistons and con rods are all balanced, so balancing isn't an issue.

And the issue with an offset on the pistons is nullified because the arrows on the pistons are all facing toward the front of the engine, so the offset would be identical regardless of the connecting rods.

Here's more detail given to show what I did:



And this is what RAVE says:


And the orientation that RAVE directs:



So, the real question in my mind is if the offset of the bearings in the connecting rods puts the pairs of bearings close together or far apart, and if the oil hole would be aligned in any specific way. I'll check that this evening because I can, or if someone else knows, please share!
 
  #18  
Old 10-01-2014, 04:09 PM
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"So, the real question in my mind is if the offset of the bearings in the connecting rods puts the pairs of bearings close together or far apart?"


The short answer is the offset would put the bearings closer together.

The long answer is:

In your first picture of the engine you show the dot on cylinder #1 rod to the front of the engine and the dot on cylinder #2 rod aiming to the back of the engine and that would be incorrect and would have the offset areas to the inside between rod 1&2. same with 3&4, etc. that would put your bearings farther apart.

So if when you pull the pan and the rods are not in the correct direction with the dots facing each other on rods 1&2 and 3&4,etc. then the offsets are aiming the wrong direction.

If you did manage to get the pistons in correct with arrows aiming forward and then the rods in backward with the dots not facing each other then seems like you would have pulled the rods out of square with the crank when torqued and if torqued down while miss-aligned like that you may have squeezed the bearings too much on one side of each bearing (one side squeezed on top bearing and the other side squeezed on the bottom bearing) since one rod in each pair would be leaning forward a hair and the next backward a hair. Wrist pin bushing could have been squeezed on opposite sides top and bottom as well.

Even though everything may seem to line up like this and bolt in, it will not work because your rod bearings will be riding on the crank in the wrong location (about 1/4" off due to the offset being turned wrong direction) and the bearings will not be close together, like they should be, on rods 1&2, 3&4, etc..

So if you can look into the bores with a scope and the arrows are all aiming forward and pull the pan and the dots on the rods are facing each other on 1&2, 3&4, 5&6, 7&8 then you are good.

In your sketch, the right hand side that you call con rod inner surface (offset) would be the side of the rod that would go away from each other and toward the ends of the rod journal on the crank. The side you are calling offset is the side of the rod without the dot.

The dot on the rod is the side of the rod that the bearing is closer to.

On cylinder 1 the dot on the rod goes toward the back of the engine

On cylinder 2 the dot on the rod goes toward the front of the engine

So... since cylinder #1 is more forward (closer to the front of the truck) than cylinder #2, then cylinder #1 rod is in front of cylinder #2 rod and goes on the crank more forward (closer to the front of the truck) than cylinder #2 rod

Now... since the dot on the rod on cylinder #1 goes back and the dot on the rod on cylinder #2 goes front then if you have both rods #1 and #2 on the crank on a bench and stood both rods straight up next to each other then the dots would be facing each other and the bearings on #1 and #2 would be to the inside and closer to each other than if turned the other (wrong) way.

Now if the rods were put in wrong with the dots aiming away from each other then there would be a large gap between #1 rod bearing and #2 rod bearing with both of the offset areas in between the two rods and that would put the bearings closer to the counterweights. This would be incorrect.

Not sure if you can follow all of that but the bearings between #1 and #2 and are to the center.... the offset unused area would go opposite each other toward the counterweights on the crank.

same on #3 and #4 dots facing each other bearings to the center

then #5 and #6 same

and #7 and #8 same

anyway, I'm probably going around the world to try to explain this but, everything has to right so... I hope you follow me?

If the pistons all have arrows aiming forward toward the front of the engine I don't think it would matter which side of the engine the actual pistons go on as long as all of the arrows aim toward the front of the engine.

Don't matter which side the rods go on ether as long as the dots are facing the right direction putting the offsets in the right direction.

Just keep the dots on the rods facing each other on 1&2, 3&4, 5&6, 7&8, and you'll be good on the rods and the offsets on the rods will be in the correct direction. The piston arrows must aim forward.

If you do end up tearing this all back down, and buying new head gaskets and new head bolts/studs you may want to seriously consider new rod bolts as well.
 

Last edited by RicketyTick; 10-02-2014 at 07:40 AM.
  #19  
Old 10-01-2014, 04:22 PM
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If that image you created showing the position of the domes and arrows is correct then you are OK. As for the head gaskets, I would hesitate to reuse them as they do get crushed when torqued. They may work fine once re-torqued but I wouldn't risk it. Regarding the head bolts, once they are torqued the final 180 degrees they have yielded and are now longer than when hew so if you try to reuse them, they won't provide the same clamping force once tightened following the same sequence. I just bought a full set of AllMakes bolts from Miami British for $30. Get them.
 
  #20  
Old 10-01-2014, 10:59 PM
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I got in touch with the guys at BPUtah and was able to pick up a set of new gaskets and bolts for about 100 this evening. They don't have a storefront, but the guy who runs it met me at the storage facility that the parts are kept at and I bought them from him that way. Easy way to get needed parts ASAP.

I have the In-laws staying with me 'til Sunday, and they are already questioning why an engine is in the living room, exhaust is on the dryer, and transmission is in the dining room (they didn't see it disassembled on the dining room table, though!), so I'm trying not to do too much of the engine work while they're in town. I just want to get this sucker assembled and going, though, so we'll see how long my patience holds out.

End of the day conclusion: I do need to put the pistons in their correct order and orientation, so I already disassembled it all this afternoon. I probably could reuse the bolts and gasket and not have an issue for a good while. The strain in the bolts would make them a harder(that's what taking a material beyond yield does, plastic deformation) to get the full 90 degrees out of the last stage, so maybe 60 degrees instead, but I've just spent 3 months and almost 4k on this vehicle being rebuilt, and I can't pull the engine in December if an issue does come up. I need reliability from this thing. for the extra $100, it is worth my peace of mind, even if the stress strain/curve can tell me where I should expect the bolt to properly deform, and the gasket is almost certainly usable. Let's hope the threads on this block don't mind another good torquing tomorrow!
 


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