WBX 2.1 DJ Rebuild

[Wilber]

So after just installing my newly rebuilt 2.1 DJ I went for what I thought was a final test drive on Tuesday eve. Going up a large hill near me tested the engine under a little load called gravity, kept it in 3rd and was pulling well around 3750 rpm doing 35 odd mph.

Until; what seemed to be a tappety noise coming from the engine.

Pulled over, lifted the lid and at idle all sounded fine, but over 2K rpm a bag of bolts.

Pretty sure no. 4 cylinder big end has gone and feeling pretty gutted about it all.

Thinking it could be a con rod bolt either snapped or worked loose, but will not know until the engine is split.

So I'm going to take your "Itchyfeet"s advice and document the saga for other to know the steps.

Lets start at the beginning, getting the van into position and heading out into the snowy weather to jack her and start draining the fluids.

[itchyfeet]

Gutted for you Will
Have you checked the waterpump, they sould pretty bad when impellar hits the block , worth ruling out broken tappets too before stripping, you can crush push rod tubes out I have plenty.

[Wilber]

I'll do a sound recording in the morning and post it here to see what you guys think.

Loving your optimism but pretty sure I can hear a double noise, the piston hitting the head then the slap of the con rod and crank.

Well that's my thoughts anyway.


Sent from my iPhone using Tapatalk Pro

[Mr Bean]

I have one of those beasts and out of interest I would be be keen to how you arrived a your diagnosis. My failed big ends - and I have sadly done a few in my time - have always bonked rather than tapped. Did the oil warning light come on?
The only way I could think of sussing that without stripping it would be to remove all plugs, turn the engine over slowly by hand and measure the lag or lost motion of the piston movement in relation to crank angle over top and bottom dead center. I Would hate to strip down and find something which could have been fixed without doing so.
Cheers
CS

[Wilber]

Hi CS,

That's a good point and will spend some time tomorrow on your recommendation as when a big end went on a WBX I had a few years ago that also bonked.

Only difference is that was an MV and this is a DJ.


Sent from my iPhone using Tapatalk Pro

[itchyfeet]

Did you reuse stretch bolts in con rods, fit non stretch or buy NOS con rods with stretch bolts?
New stretch bolts are NLA

[Wilber]

The same stretch bolts for the con rods were reused.

You think one of the nuts may have worked loose?


Sent from my iPhone using Tapatalk Pro

[itchyfeet]

Not supposed to reuse them, they could have been reused before also.
I suppose once over stretched they no longer hold a torque or snap.

[Wilber]

Managed to get a mate round to help get the engine out this afternoon, something didn't want to do but was sure the the issue it has is more than just an auxiliary component.


Getting the van prepped for surgery.


Engine ready for component removal.


Selecting the right tools.






1 hour later and it's out!




Naked engine!



http://i812.photobucket.com/albums/zz50 ... 0Issue.mp4" onclick="window.open(this.href);return false;

If you click the image above it's a link to a video showing the cause of the knock. As you can see, a little more movement on no. 3 piston proving a big end issue. Now just need to find out why it happened!

[itchyfeet]

I guess that was origionally a DG?
Very interested to see what is was.

Not the best weather to be doing this
does it have an oil cooler?

[Wilber]

The van was originally a DG until a few weeks ago.

Still using the early water system and have plumbed the DJ oil cooler off the engine bleed valve block as mine had 2 x 16mm connections that was looped. I believe this originally fed an auto box so a little confused why it was on my bus?




In this image you can see the oil cooler hanging down and connected to the bottom of the engine bleed valve block

It ran perfectly for 2 weeks, even whilst going through the teething stages so happy with the final setup.

Anyway the engine is out and know what the issue is, just need to strip it down, split the case and carry out a post mortem.

[itchyfeet]

Ah yes I see the oil cooler now but pic above has oil filter on engine with no cooler which is confusing?

[Wilber]

I removed the oil cooler as couldn't get any oil pressure on Wednesday night. Was trying to confirm that the oil pump was working as it should so eliminating one thing at a time.......

Oil pressure was wasn't even reaching 0.3 bar when turning the engine over on the starter without it firing. This was the origin of my doubts.

[itchyfeet]

ahh OK I see now.

stripping the engine is the easy bit, putting it back is what takes time as I'm sure you know.

Think of it as a learning curve

[Wilber]

So it's been a while but have an update on the low oil pressure and knocking.

Basically one of the bolts on #3 big end had worked loose and fallen off! This meant the conrod was loose on the crank and the noise was the piston hitting the head at the top of the stroke,

Luckily the shells hadn't been damaged and the oil flow to the big end was good. Also the bolt was sitting on the bottom of the engine and hadn't caused any damage.

A spare conrod was fitted with the original shells, checked for play, then torqued up. While I was in there checked the torques of all the other bolts which were fine.

Since the re-rebuild I have covered nearly 5K miles without a glitch and the engine pulls like train.

Did a 3 week round trip to South France, Italy, Switzerland, Germany Belgium and also many destination in the IK over the summer and couldn't be happier with the setup.

Hope all those other engines out there are doing as well as mine.