Embarking on an engine rebuild journey - some advice needed

[Crasher]

I have used Red Line assembly lube for decades and hundreds of engines but I could not get any and used Torquo, then found an unopened post of RL in the stores in the wrong place.

 

[siLc]

OK, so the pistons are now all in. Was tightening up the conrod bolts 30Nm+90 degrees. I used Kolbenschmidt 50009202 bolts and I went a bit over 90 degrees with one bolt, so it's best to replace and re-do that one? Those were 0,76€/piece so rather cheap compared to Elring at 2,5€/piece or original 3,5€/piece - to be honest, it didn't feel all that good when doing the 90 degrees with a 1/2" long breaker bar. Maybe re-do the whole thing with original bolts?

 

[RGH0]

I always use the best available bolts on conrods. Typically I use ARP bolts. I don't know if they make them for your engine. Conrods bolts are not normally torque to yield but torque to get the correct stretch within the elastic range which for a normal conrod design is around 5 to 6 thou ,a slight extra few degrees of turn should normally be withing the stretch tolerance

 

[siLc]

RTMG seems to be a provider for EA111 series engines but they don't have conrod bolts for that. I'll just get the originals...

 

[Crasher]

I only use genuine rod bolts if not using ARP.

 

[siLc]

My ordered genuine rod bolts arrived. When I first assembled all the big ends, I noticed that the first cylinder had a bit more side to side play on the crankshaft journal. When moving the big end on the crank journal end to end, there's a slight metallic noise at the wrist pin when bottoming out at each end. So I took piston one out again, took out the wrist pin and re-inspected the small end bushing - there is some wear. Since there's a metallic noise, the conrod would probably have to be replaced?

 

[Crasher]

The rod can be rebushed by an engineer

 

[RGH0]

is the metallic noise due to wear clearance of the wrist pin and con rod small end bushing or due to something else hitting as you move the rod ? I would get measured the wrist pin and small end bush versus the specifications and get it re-bushed and honed if needed

 

[siLc]

is the metallic noise due to wear clearance of the wrist pin and con rod small end bushing or due to something else hitting as you move the rod ? I would get measured the wrist pin and small end bush versus the specifications and get it re-bushed and honed if needed

I figure it's wear clearance of the wrist pin and small end bushing, as the big end wasn't hitting the ends of it's crankshaft journal. None of the other pistons had this metallic noise in their installed state. For good measure, I took the other pistons out again and they had less wiggle at the small end bushing. Going to seek the help of a machine shop for this.

 

[RGH0]

I was just trying to reinforce that without precision measurements you dont really know what is the issue. Taking it to a machine shop should confirm the issue. But it could be something else like the wrist pin moving in the piston and hitting the locating clips. The wrist pin should be a smooth sliding fit into the rod with no side movement when inserted. If you can feel any side movement at all then it is probably worn and machine shop measurements should be able to confirm that

 

[siLc]

I consulted with the machine shop who measured the cylinder bores. Since the engine wasn't making a ticking noise previously, this noise would probably be fine. But if I wanted to be sure, just replace the conrod. Shop hourly rate of measurement and replacement of only the bushing is much more costly than just buying a new conrod.

 

[RGH0]

if buying a new rod make sure it weighs the same as the old rods both ends

 

[siLc]

if buying a new rod make sure it weighs the same as the old rods both ends

So the rod should weigh 514g according to https://www.autodoc.co.uk/et-engineteam/15928183#connecting-rod
Will need to get a scale appropriately accurate for that.

Anyway I talked to a familiar mechanic, who handled the offending piston, another piston for comparison and confirmed the offending piston having more play in the small end. Also received a inch-scale 0-1" micrometer to carry out measurements of the wrist pin and small end bushing. Since I'm not in the US, metric is my usual thing but I made it work. The mean diameter of the wrist pin is 0,7476", decreasing to 0,7475" (1 line difference on the Vernier scale) where the beads of small end wear spots are. As for the conrod small end inside diameter, I only have a Vernier caliper, so that's not a lot of help. Anyway I set it to 19mm and moved the jaws inside the bushing - some side-to-side play was present.

Will measure other pistons soon.

 

[siLc]

So I took the other pistons apart, cleaned the oil off and measured the wrist pins. Those were between 0,7477" and 0,7476" in outside diameter and when I put those into piston one conrod, some of the previously noted play was taken up. So I must conclude there is some wear both in the small and and in the wrist pin. Will replace the conrod and see if play becomes acceptable. I'm guessing wrist pins aren't readily available seperately?

 

[Crasher]

Gudgeon pin old boy, wrist pin! Wear of the pin is almost unheard of, it is the rod bush and piston bore that wear but usually just the bush BUT it looks like these rods are hard to get bushes for and as new KS rod is so cheap, why bother https://www.kmotorshop.com/en/artic...-et-engineteam-03c198401a-03c198401d-50009179. I would rebore it 0.5mm and fit Nural 87-433907-10 pistons

 

[siLc]

Things have been progressing slowly. I put in one new conrod and installed the cylinder head, which I finally after one and a half months I received back from the machine shop. Before doing that, since the normal FSI gasolene injectors were removed along with the lower part of the intake manifold, they required their teflon seals to be replaced and also required a spot of ultrasonic cleaning because of deposits left behind by the oil burning. I bought four VW genuine seal kits and since I lacked the special tools, I had them replaced, reinstalled into the lower part of intake manifold and that, in turn, installed on the cylinder head.

I long mulled about whether using a updated VW genuine but very-very expensive chain kit 03C198229B or go with an affordable updated aftermarket kit, but I made the compromise to go with Febi Bilstein 181349 chain kit + appropriate INA oil pump chain kit. This is, after all, a kind-of budget build.

The second thing I mulled over whether I, without any such experience, can properly lay that 2mm bead of green anaerobic sealant on the camshaft module's sealing surfaces without it getting into any of the numerous oil passages. Factory manual also specified using silicone in some areas but diagrams were quite unclear where...

The last thing is whether to trust the T10171 and T10340 timing tools from the orient, which I used for engine disassembly. I got to comparatively measure them with genuine VW tools - camshaft angles relative to each other slighly more apart. Genuine T10340 is shorter by 1mm, so crankshaft may not be at TDC with the aftermarket tool. So I decided to have the camshaft module installed and chain kit properly timed up in the shop where I got all the other previous misc stuff done. Will cost me probably 4 hours of labor, but it will at least be done properly. Then I'm home free putting the engine back together.

 

[RGH0]

Getting a little excess anerobic sealer inside the engine is generally not a big deal as it stays liquid and dissolves in the oil. It only goes solid on the actual joining surfaces when oxygen is excluded. If joining passive surfaces such as aluminium you should use a spray activator / catalyst to ensure proper sealing as its is active ferrous metals that catalyse the anerobic solidification reaction. It is not like silicone sealants where any excess goes solid inside an engine and globules can block up oil suction strainers and small oil passages

 

[BlueR32]

I always use the best available bolts on conrods. Typically I use ARP bolts. I don't know if they make them for your engine. Conrods bolts are not normally torque to yield but torque to get the correct stretch within the elastic range which for a normal conrod design is around 5 to 6 thou ,a slight extra few degrees of turn should normally be withing the stretch tolerance

Just an FYI for anyone rebuilding a VW engine - VW has used torque-to-yield connecting rod (and in many cases cylinder head), bolts for decades. By tightening them to the specified angle they are placed in the plastic deformation range of the metal - which is why they require replacement every time the engine is disassembled. If you reuse these "stretch bolts" they will not hold the proper torque when actually in service because the metal has already yielded once.

With ARP of similar high performance aftermarket con rod bolts as noted measuring the bolt stretch places the bolt in it's optimal tension but does not permanently stretch the bolt as happens with a torque-to-yield bolt. Replacement OEM style aftermarket bolts unless specified differently are also one-time use torque-to-yield bolts like the factory bolts. The aftermarket high performance bolts are typically a requirement for higher than stock engine RPM because the OEM or aftermarket "stretch" bolts were never designed to handle the significant increase in jerk moment load at TDC that occurs with increased RPM.

 

[siLc]

Getting a little excess anerobic sealer inside the engine is generally not a big deal as it stays liquid and dissolves in the oil. It only goes solid on the actual joining surfaces when oxygen is excluded. If joining passive surfaces such as aluminium you should use a spray activator / catalyst to ensure proper sealing as its is active ferrous metals that catalyse the anerobic solidification reaction. It is not like silicone sealants where any excess goes solid inside an engine and globules can block up oil suction strainers and small oil passages

Thanks! I didn't know that. The camshaft module is aluminum and the cylinder head seems to be iron.

The thing is the camshaft timing tool probably should be installed before installing the camshaft module. If I install it with the usage of my oriental T10171 tool, chances are I will be causing the shop more work to get their genuine T10171A installed because the camshafts will be under pressure from the valve springs. Timing chain kit has new toothed gear wheels for both camshafts, so the old ones have been already removed, so nothing to grab onto to rotate the camshafts after installing the camshaft module. There are no fixing notches etc. for the gear wheels - they will only be held by their central bolt, which are torqued to 40Nm and 50Nm plus 90 degrees.

 

[RGH0]

Put in a bolt in the end of the cam shaft or grip the cam between the lobes with a set of big multigrips and you should be able to rotate the cams OK. At least I can on engines i build