Hi I had watched this thread from reading a while ago, just interested in anything engine(call me geek
) great read.
Never seen one of those Honers before. Only seen/used the long block ones.
Can I ask did you just hone up? I was always under the impression you needed the cross hatch type pattern.
Asking no criticism of your work.
J
) great read.Never seen one of those Honers before. Only seen/used the long block ones.
Can I ask did you just hone up? I was always under the impression you needed the cross hatch type pattern.
Asking no criticism of your work.
J
jamesmartin
Well-Known Member
ideally when hone you would remove some material,a quick surface scoring will polish off fairly quickly your better a thou over size but decent hone
jamesmartin
Well-Known Member
they give a cross hatch as long as you match speed and strokeHi I had watched this thread from reading a while ago, just interested in anything engine(call me geek
Never seen one of those Honers before. Only seen/used the long block ones.
Can I ask did you just hone up? I was always under the impression you needed the cross hatch type pattern.
Asking no criticism of your work.
J
Ok I can understand that.but looks only upward stroke used here.
But is a cross hatch required/better/not needed ?
J
Henry_b
Think outside, no box required.
The above is a brush hone, or as i like to call 'em dingle ball hones
The correct angle for cross hatch lines to intersect is approximately 41-45 degrees. Too steep an angle promotes oil migration down the cylinder resulting in a thin oil film which can cause ring and cylinder scufflng.
Too flat a cross hatch angle can hold excess oil which conversely causes thicker oil films which the piston rings will ride up on or hydroplane. You'll also get excessive oil consumption
A "cross-hatch" pattern is used to retain oil to ensure proper lubrication and ring seal of pistons in cylinders. A smooth glazed cylinder wall can cause piston ring and cylinder scuffing, it'll also cause an improper seal which is bad
jamesmartin
Well-Known Member
the correct angled cross hatch is essential
Thanks @jamesmartin & @Henry_b
Just wanted to understand if modern thinking had changed things from my old fashioned learnings.
Obviously not
J
Just wanted to understand if modern thinking had changed things from my old fashioned learnings.
Obviously not
J
Bennehboy
Well-Known Member
@marjon the cross hatch is there, but the photo was from before I wiped the bore out, so you only see the exit angle of the brush in the atf/slurry which looks like a single line.
@jamesmartin I'm probably going to give it another blast anyway. It's had three sets of 12 strokes in opposite directions up to now. The drill I'm using is probably slightly too high rpm so I've to go at it like billy-oh to get the right angle.
@jamesmartin I'm probably going to give it another blast anyway. It's had three sets of 12 strokes in opposite directions up to now. The drill I'm using is probably slightly too high rpm so I've to go at it like billy-oh to get the right angle.
TorsionBhudda
Well-Known Member
Excellent thread just spent last 2 days at work reading it. Good luck with this engine rebuild
Bennehboy
Well-Known Member
Cheers buddy, glad I helped you pass the time
Bennehboy
Well-Known Member
Looks like I need at least 1 new piston.....
This is No5. I know what caused this, I had a failed injector about a year back - self inflicted because numb nuts here didn't tighten the injector clamp down... this was when I'd done the injector seals 3 times in a row chasing an imbalance. Must've dropped part of the tip into the bore :/
This is No5. I know what caused this, I had a failed injector about a year back - self inflicted because numb nuts here didn't tighten the injector clamp down... this was when I'd done the injector seals 3 times in a row chasing an imbalance. Must've dropped part of the tip into the bore :/
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Bennehboy
Well-Known Member
OK, so more problems....
Pistons 2 & 5 have excessive wear around the edges of the piston crown... but it's not on the thrust side, having given the pistons a wiggle test on the wrist pins I think the small end bushings in the conrods are shot. No2 is worn on the front side, and no 5 on the rear side - I reckon this is probably piston slap due to the piston rocking on the wrist pins. All 5 pistons & pins were new at the last rebuild (60k miles ago), looking back at the pics 2 & 5 had the same sort of wear on them. Clearly I missed this at the time.
Anyhow - 2 new conrods required.
Pistons 2 & 5 have excessive wear around the edges of the piston crown... but it's not on the thrust side, having given the pistons a wiggle test on the wrist pins I think the small end bushings in the conrods are shot. No2 is worn on the front side, and no 5 on the rear side - I reckon this is probably piston slap due to the piston rocking on the wrist pins. All 5 pistons & pins were new at the last rebuild (60k miles ago), looking back at the pics 2 & 5 had the same sort of wear on them. Clearly I missed this at the time.
Anyhow - 2 new conrods required.
Bennehboy
Well-Known Member
For the cost of some petrol & some red wine I now have in my possession 5 x replacement pistons & rods, a spare crank, a spare oil pump, and assorted other D2 parts. This down to the amazing generosity of a member on another forum. It's this type of spirit and generosity that makes these forums & the land rover owners community so fantastic!
So, you might ask why these were going spare? The original engine had shredded a valve spring, pretty much destroying most of the top end, and leaving a nice stamp mark on no 4 piston crown.
All of the small end bushings on these seem really nice and tight compared to mine, I dropped a conrod out of each set and mine are way more worn.
I'd love to swap all 5 rods in but I'm not sure I can trust no4, so will keep the best one from my set & swap 4 out.
I may also swap my 2 'slapped' pistons with 2 of these, and resell the brand new ones that I just purchased - we'll see.... I can't get the vehicle back together this weekend because I'm waiting on an AP Racing clutch plate & Helix cover to arrive.....
Anyhow, some pics:
The pistons are now having a nice paraffin soak.
So, you might ask why these were going spare? The original engine had shredded a valve spring, pretty much destroying most of the top end, and leaving a nice stamp mark on no 4 piston crown.
All of the small end bushings on these seem really nice and tight compared to mine, I dropped a conrod out of each set and mine are way more worn.
I'd love to swap all 5 rods in but I'm not sure I can trust no4, so will keep the best one from my set & swap 4 out.
I may also swap my 2 'slapped' pistons with 2 of these, and resell the brand new ones that I just purchased - we'll see.... I can't get the vehicle back together this weekend because I'm waiting on an AP Racing clutch plate & Helix cover to arrive.....
Anyhow, some pics:
The pistons are now having a nice paraffin soak.
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Are those thrust faces on the piston skirts impregnated with anything?
Hope it wasn't a cheapie £2.99 bottle of plonk
Hope it wasn't a cheapie £2.99 bottle of plonk
Bennehboy
Well-Known Member
Are those thrust faces on the piston skirts impregnated with anything?
Hope it wasn't a cheapie £2.99 bottle of plonk
I've no idea if they are impregnated, the pads look no different post clean to before...
And no it was 3 quite nice bottles
Anyhow I'm going to use 3 of these + the 2 new ones, most of mine have signs of some slap around the top - I may need to buy a rod yet, or chance the one from no4... I'll measure it up first though.
Mainly just need to clean everything down now but don't have the energy.
Also looks like I could do with a new viscous pulley bearing.
