I enjoy your meticulous work and admire your skills, subscribed.
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Hi All,
Thought i would share the process of my build and assembly of new 4.6L V8 to go into my disco 2.
We all enjoy a good build thread that is picture intensive showcasing some beautiful engineering and there hasn't been one for a while.
I do not wish to get into who or what has caused me to go down this road and end up in this position but merely to share my enjoyment of assembling my new motor and getting some constructive input and discussion going.
To start my disco 2 is a 2001 stock standard 4.0L that will now get an upgrade to a 4.6L.
I was fortunate enough to pick a complete sub-assembly at a great price from TwinDisco about a year ago.
I had a very clear idea how I wanted to go about this rebuild and I was not willing to compromise on quality or cost for the sake of getting the job done, hence it has taken the better part of a year with lots of questions to many people and hours of research.
Finally we are in the fun part and the final stretch.
So to start off I picked up my freshly re-engineered block last weekend from Miclin Motor Engineering down in Pinetown.
They were recommended by EbenH and after discussions with other engineering works I knew they were the only place I was willing to go to have the work I wanted done to the standard I was looking for and man did they deliver.
Work done:
- Re-Sleeve block with top hat liners and a viton O-ring in the bottom of the sleeve to create a complete seal behind the cylinder liner walls
- Pressure test block
- Reface block
- Fit new CAM bushes and resize mains and big-ends to match bearings (1 Thou over)
- Fit new pistons to rods and check clearance in bores
- Hone rod journals and sand blast rods
- Grind crank to 1 Thou over
Freshly wrapped like an early christmas present
Beautiful cross-hatched honing pattern
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Attention in the small details speaks to quality - all rods stamped with corresponding cylinder number.
Thats it for an appetizer to wet the pallet, I have all my parts and am waiting on some assembly lube to arrive before I start assembling bearings, crank etc.
I should get my heads back by the end of this week (more on that when the time comes)
I enjoy your meticulous work and admire your skills, subscribed.
Mitsubishi Triton DC 3.2 A/T 4X4
2007 Hilux 2.5 D4D SOLD
Subscribed, I miss my D2 V8 everyday, I should never have sold it![]()
Cruiser 76 V8
Disco 4 XS
Going to be a great thread
There is no such thing as inclement weather, only poor selection of clothing.... or Vehicle
2010 Hummer H3 5.3lt V8, 300 HP, FDL, RDL, CDL, TC and 4:1 Low Range
Discovery and Range Rovers: SOLD: enough is enough
I am going to watch this like a hawk. Would you mind sharing costs, PLEEEEEASE
Alan
_________________
Range Rover P38
Defender on Steroid's (Sadly sold)
Previous: Pajero 3.5 V6 (Gas Guzzler)
Series 3 109 SW (Tortoise)
Platkar Ford Fiesta 1.6tdi (Swambo's present)
If Eben Henning says they're good, then you believe him.
I miss his knowledge.
Also subscribed... Really wanna go this route on my V8 as well..![]()
2011 Freelander 2 SD4 HSE AT.
1999 Discovery II V8 XS AT.
2016 Campmaster Compact 100 trailer.
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And the cloves 🤷#♂️ Nice when you build it your self
1995 300TDi Defender with VGT Turbo
2002 Defender with LS1 MS3 ECU, 4L80e, LT230 1.222, Lockers and HD CW&P, 35" with 4" Lift
While I wait for the assembly lube and oils to arrive I thought I would get some of the other prep work done.
Will be replacing the rings that came with new pistons to Goetze rings, so I started fitting rings, checking groove clearance and ring gaps, maybe someone can advise here.
The spec for groove clearance is 0.05-0.1mm and I cannot get a 0.05mm feeler gauge into the gap, I dont have anything smaller but would estimate the gap to be a hair under 0.05.
From what i understand and have read some piston manufacturers and engine builders spec groove gaps starting at 0.01mm but that would be for a high powered race engine, which this is not.
Would love to get some feedback and input from anybody with more knowledge on these gaps, consequences of this gap being to tight can be pretty catastrophic.
Will continue checking rest of the gaps over next few days to get a complete picture.
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Ring gap is critical if the cap is to small the rings will hit each other due to heat expansion, as there is no where to go as ring faces are in contact then they expand out wards putting more pressure on cylinder walls resulting in more heat and then more damage, so get it into speck, also faces need to be parallel to each other you need a proper ring gap file machine to do that
like this
Last edited by clivemd; 2019/12/04 at 10:33 AM.
1995 300TDi Defender with VGT Turbo
2002 Defender with LS1 MS3 ECU, 4L80e, LT230 1.222, Lockers and HD CW&P, 35" with 4" Lift
[QUOTE=Jay_B;4283494]The spec for groove clearance is 0.05-0.1mm and I cannot get a 0.05mm feeler gauge into the gap, I dont have anything smaller but would estimate the gap to be a hair under 0.05.
From what i understand and have read some piston manufacturers and engine builders spec groove gaps starting at 0.01mm but that would be for a high powered race engine, which this is not.
Would love to get some feedback and input from anybody with more knowledge on these gaps, consequences of this gap being to tight can be pretty catastrophic.
Will continue checking rest of the gaps over next few days to get a complete picture.
During appy training we were taught to measure the ring groove in the piston at 6 places around the piston and then measure each ring thickness also at 6 evenly spaced places around the ring. The difference between the two measurements is the gap and these measurements were done with a micrometer. I have used a good quality digital vernia to do these measurements on some of the race car motors I have build over the years.
The ring end gap is measured at 4 heights in the bore after using the piston the ensure the ring is square to the block. This measurement is done with a feeler gauge.
If the new piston rings don't come with instructions for ring gaps like some of the high performance parts do, it will be safe to use the standard gaps specified in engine rebuild manual. This is what I found in copy of the manual that I have.
Insert piston rings into cylinder bore, use the
piston to hold the rings square to bore and
check the ring gap.
l 1st compression ring = 0.30 to 0.50 mm
(0.012 to 0.02 in).
l 2nd compression ring = 0.40 to 0.65 mm
(0.016 to 0.026 in).
l Oil control ring rails = 0.38 to 1.40 mm
(0.015 to 0.055 in).
The humble person makes room for progress; the arrogant person believes they’re already there.
2004 Disco 2 Td5
Suzuki SJ410 (being rebuild)
VW Touran 2.0Tdi
Lotus 7 (replica - not a kit)
Freelance Photographer (part time)
Member Of: Southern African Freelancers' Association
Thank you Clive and Paul for the input.
I am aware of how critical the ring end gap is and will still get to measuring those in the bores.
Measurement I am asking about is the axial clearance gap inside the piston grooves, it seems to be spoken of a lot less than the ring end gaps.
The one piston I have checked so far I have an axial clearance of approx 0.01mm which is tighter than the spec of 0.05
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