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Master Coalroller
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Worst honing job I’ve seen. I’d pull the compression rings and do a gap test to see what condition they were operating under. Is it likely this was a recon that didn’t get its liners honed at all?
 

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Worst honing job I’ve seen. I’d pull the compression rings and do a gap test to see what condition they were operating under. Is it likely this was a recon that didn’t get its liners honed at all?
Or in car rebuild with dunny brush hone on a drill

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Master Coalroller
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Yeah true HZ, never know what you’re opening up when it comes to TD engines.

JJJag in that pic: post #63, looks like you have an odd piston/gudgeon/conrod combination there... maybe I’m wrong, but I’d say this would cause rotational imbalance at least. Best investigate that
 

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Master Coalroller
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Ok just re read the thread. Liner protrusion is critical to head gasket welfare. Even if it’s in spec and you don’t pull the liners, use a stud kit, not head bolts. Not sure if you can get an accurate measurement on deck condition with liners in the block. These blocks can warp after overheating and head gaskets will not usually survive until recitified. Studs will give you sustainable tension.
That polished spot on one of the bores, is it #4 or #5 or between that Siamese point? Because that is where all these blocks crack behind the liners when properly overheated. Between 4&5.
Given the condition of the head gasket, poor honing, mismatched part installation, possibly cyl #4/5 have polish marks on bore, and harmonic balancer issue, you might have an engine that’s been slapped together for a quick disposal.
I’d pay close attention to block deck condition, liner protrusion and especially size all the liner bores. This will determine if you should strip the block and go the full monty.
If there’s an issue where that polish bore mark is, it may be in the parent bore behind the liner. However alternatively if that odd piston/gudgeon was in that bore, it may be piston slap induced by poor balancing that caused that polished mark. You really need someone to inspect and give a secon opinion because some things just aren’t adding up.
 

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Discussion Starter #68
thanks boundary and everyone
just trying sus it all out and give it all a measure up so i have a rough idea whats going on
it doesn't need to get straight back on the road
but I really appreciate all your valuable input.
a few respected members said I was lucky to do the lap with current internals lol
so keeping on topping up the fluids prob keep it alive
the first photos are 4 and 5
well no 4 does have slight glaze on ex side is that from big end bearings or piston pin
thought I'd post the others
all vert scores are on inlet side
 

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Master Coalroller
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Looks like your number 4 (with the fat gudgeon?) is the odd one heavier than the rest. Piston, gudgeon pin and rod. Gotta sort that out and have symmetrical piston /rod combinations only.
As far as the block goes, if the bores mike up ok and there’s no swelling areas especially at the Siamese points, your may be safe to continue. Next is the deck for square and flat, and last and equally as important liner protrusion.
If you pass all these checks, I’d still go for stud kit. After honing correctly, make sure to gap ALL your rings (including oil) in their respective bores before assembling pistons (also check compression ring installation may be directional), and once assembled check piston protrusion.
 

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Discussion Starter #70
thanks
is that rod and piston combo or a rod change
my liner protrusion isn't the best at .3mm
 

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Master Coalroller
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All the pistons rods and gudgeons should must be same family, preferably weight balanced. You’ve at least one foreign gudgeon, and as you say probably a conrod too. I’d suspect that piston is foreign also as its heavier than the rest.
I can’t remember the protrusion for TD42 it’s been a few years since the last one I recon and the specifications aren’t fresh in my head, only the process lol
 

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Discussion Starter #74
so the pins are all 30mm od and have a 7mm wall but no 4 is the full width of the pin and all the rest are countersunk
anyone had or know which is which
marking on 5 of the rods 9vh
odd rod 1 A
thanks again for all help
 

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Jeez this thing has been slapped back together in a big way.
personally. in terms of cost vs time vs result. If you wanted to persist with this motor i would be stripping the liners and checking the parent bores for damage. looks like its either been hot or sucked in a heap of water and bent a rod somehow. possibly blown headgasket. Id be wanting ensure parent bores are ok and deck is perfectly flat before going any further on this engine.

But in all honesty. You would be better off chasing down a good td from someone who is doing a conversion or similar and just bolting that in. will be cheaper and unless you want 200kw there isnt much to gain in a rebuild.

Fwiw though. when you buy piston kits it will include gudgeon pins and clips so they will all be the same. your going to need a matching set of rods of similar weight so that once balanced you dont have big discrepancies in weight removal. and only use genuine or mahle (oem manufacture) pistons and liners. i used arp race series bearings for mains and big ends. they are coated so a lot better. arp head studs. genuine gasket kit.
But your starting to find a lot of wear in timing gears and so forth. A different engine is probably a better option.
It cost me close to 5k trade prices to bare block rebuild my td with everything fully coated and balanced. the only thing i didnt replace was flywheel with alloy but i took a few kg out of my original one.
 

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Discussion Starter #76
thanks Benos
yeah what looked to be a quick hone has turned to poo lol
are the gugeon pins like that on some other motors not sure
as previous I've never really known what was the internals or if it was a t motor
does have longer squirter, 21mm oil pump gears not that this helps with anything
I'll keep pulling to bits and see what else there is to see,
the only positive I guess that even with the 50gram imbalance she still got the lap done and got to placed other cars wouldnt 😂
but will have weigh up all options even 2nd hand motor don't guarantee whats inside
strange this motor had compression up to spec and only pulled down for the loose damper(imbalance maybe) and oil and coolant leaks
thanks again for all the help and feedback
 

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Master Coalroller
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You still go alright with mismatched parts, but fatigue sets in and service life is much less. Like 100K Klm’s v 500K Klm’s from an engine.
Last TD I did was $3900 parts and machining. No fuel system work, a new head was used, a full recon kit purchased, and we reused the camshaft, water pump and most other parts from 3 donor engines. Actually the crank, cam and block were from all different engines lol.
So this was outsourced machine shop work:
Block decked and liner rebates reset; liners pressed within protrusion spec and honed; new cam bearings refitted.
In my shed I built it all up.
If your bores are in spec nice and round, and your liner protrusion is within spec I’d get a new set of pistons and match a rod to the 5 you already have and using a stud kit to keep it together nice and tight.
If your liners are out of spec it’ll start to play up at the head gasket again between 10K and 100K Klm’s.
 

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Discussion Starter #78
thanks boundry
not a fan of that rod piston combo and would be the first to be matched up
so far at first glance with gauge they fairly round
but when I pop the rings in I'll be able see any distorsion and ring gaps
 

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Master Coalroller
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I PM some info for you. Use a really thin file for gapping. The ring contact faces need to be nice and square. Using a thick file will leave the faces angled.
Obviously gap to the spec in the workshop manual for each ring, and test measure in three places down the bore using a piston to keep the ring square to the bore.
If you pay appropriate respect to ring install you will have reliable performance, skip or rush it and an engine can fail down the road as far as 5000 kms, as has been done and posted on this forum.
Never use engine assembly grease on pistons or rings, only use cheap engine oil for assembly.
 
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