WBX-Unknown

[itchyfeet]

Just for interest this is the fastest WBX powered vehicle at 165.5mph
8.031 1/4

https://youtu.be/LnvzCUIgXTQ" onclick="window.open(this.href);return false;

and people say that diesels are better

[937carrera]

Nope, not biting.

Don't know if I'm giving the wrong impression here, but my ambition is limited to a somewhat half decent rebuild on this occasion.

[itchyfeet]

Don't know if I'm giving the wrong impression here, but my ambition is limited to a somewhat half decent rebuild on this occasion.

Not at all, I don't pretend to be an expert but I did manage to rebuild an engine which has proved reliable (I just did 800miles in France with no problems for the second year).
I only did it by learning from here and discussing and applying that knoledge to my best ability as you are doing.

The other engine rebuild I have done hasn't been fitted yet.

done several top ends and they have been ok too so far.

[937carrera]

I haven't been able to find the specs for the length of the single piece thrust bearing, so time to turn my head to other matters.

Con rods, not the best picture in the world but I believe I do have TTY con rod bolts at the moment. The difference being longer threads ( about 22mm) on the non stretch bolts. It's easier to look at the non threaded portion where the difference is exaggerated ?

My rod


Some other blokes picture I borrowed, thanks itchy

I think the rod has stretch/TTY fitted while the collection to the right is the replacement 8



Have I got that right ?

[itchyfeet]

yes stretch long threads
I pinched a set of non stretch from an early engine I had those are on the right as you say with short threads.
You can't buy stretch anymore on their own and you can't reuse but you can buy non stretch.

Or you can still buy NOS con rods with stretch bolts.

[937carrera]

Thanks, late bolts in an early case, following a VW rebuild. More is known than before.

That con rod bearing looks really nice, so I'm assuming they must have been replaced. I think I need to check number 3 con rod for straightness, the one with the wear on one side. That may be a job for the machine shop, I'll see if I can do a check by comparison first.

[itchyfeet]

I have two used bearings and they are pretty much the same

P1100422 by Paul_Barr, on Flickr

[itchyfeet]

. I think I need to check number 3 con rod for straightness, the one with the wear on one side. ]

Wouldn't excessive end float do that?

[itchyfeet]

Bearing sits proud, this is a larger diameter 0.4 shim and it clears the case so I can't see why you can't use 3 off.

P1100424 by Paul_Barr, on Flickr

[937carrera]

. I think I need to check number 3 con rod for straightness, the one with the wear on one side. ]

Wouldn't excessive end float do that?

I was thinking that at first, but why just that one con rod, the endfloat goes to all the journals, I do however realise it is the nearest to number 1 main.

In my reading around looking for bearing dimensions I came across a big end shell inspection chart which showed similar but much more excessive wear caused by a bent rod. As I don't know the history it is possible a rod has been bent and not replaced. I still need to check little ends and gudgeon pins too, but didn't notice anything when pulling them off. The wear is consistent with forces from the combustion stroke, no unusual wear on the other shell.

http://www.speedperf6rmanc3.com/content ... arings.pdf


Is that a picture of an early bearing with the 0.4 shim, useful to know if so, thanks. If you have it physically can you measure it, even if worn ?

[sarran1955]

Hello,

Just for comparison:

]

Here is the same view of a CT crankcase:


Cordialement,

[937carrera]

Just seen your earlier post Paul, your used ones 25.93 vs mine at 25.89mm, not too far away, thanks.

I've still got to work out how the late 3 piece bearing can be 1mm wider with the same crank and flywheel as the early one piece bearing. I'm missing something.

[bigbadbob76]

Doesn't make sense does it.
Just a thought... is the outside diameter of your CU flywheel boss smaller than the inside diameter of your DG shims?
If they're riding up the flywheel it would screw up your measurements.
Doubtfull I know but anything's worth a try.

E D I T- ignore that, I'm talking pish!!! haha
the crankshaft sits in the recess in the flywheel so shims can't ride up the boss.

[itchyfeet]

please can you repost the picture with the wear?*

I have to admit having to hammer out some gudgeon pins and it;s just possible it could bend the conrod, I have heard that said but what choie do you have?
I have had some sucess with a reamer but as they are tapered it's not the right diameter, I don't suppose the VW tool is available.

I have to admit also not checking for wear marks on the conrods of WBXMayo, WBXlog had new rods


*(As your pics are so big at around 1MB each they take forever to load on my 3G mobile devices and they do not seem to cache them so its hard to go back and reread the thread as it's sooooo slllooooooowwww, if I didn't have unlimited data I would avoid your thread on a mobile.)

[937carrera]

Con rod first. Remember axial play at 0.4mm is within spec so that isn't causing the side load



and main bearings, the wear / heat marks on number two are adjacent to cylinder 1 rod, I probably need to identify where they are in relation to the case, but these are not too bad, probably caused by clearance being too tight following a little lateral movement of the crank



I wouldn't have thought that hand tools could bend a con rod, it's generally sudden deceleration through impact or hydraulic locking that can damage them. There's no evidence of recent hydraulic locking as there's no rust on the barrels.

I haven't removed the shells to inspect the rod mounting faces yet, less confusing to leave the shells in place for the moment