Cracked Engine Case @ Oil Pressure Sender

[gvee]

Building up the engine yesterday and right at the end I realised we'd left the oil pressure switch off.
I have a Germanwagen T-Piece so I can have both pressure and temperature in the same place.

I screwed this in nice and slow and it never seemed to get any tighter at any point. So I wound it to nearly as far as the threads would go (didn't want to put it in too far) and then I noticed this...

3 f**king cracks appeared around the hole. One of the cracks goes the full length of the threads.

What can I do?

Current thought is to get some pipe and thread it in and have this welded to the case. Then tap the sender in to the end of this extrusion? Really don't want to have to split the case. Can all this be done "in-situ"?

After this I only had the exhaust left to fit before putting the engine back in the bus :suicide:

 

[subheatadey]

Hi George, must have been a tapered thread maybe? Anyway I would think it best to strip it down and get it welded back up and re-tap it, probably cost to have it welded about £25-30

 

[gvee]

"Strip it down" - ancillaries or split case?
I really don't want to have to split the case. But if I re-tap it, I guess I will have to anyway?

 

[subheatadey]

You would need to take it to a decent engineering company or someone who is good at Tig welding maybe you could find someone who has some portable equipment and would come out and do it 'in place' but you would have to make sure no swarf was going to get into the engine becasue then the fun would really start. Early cases I think were Aluminium so easier to weld mine was a AS41 case so lots of magnesium and a bitch to weld but they did it after two attempts and me rebuiling it after each attempt by the end the engine got slapped back together in less than a hour - still going

 

[gvee]

How do I ID the material of the case then?

 

[gvee]

Engine number (on a plate under the alternator pedestal): B5545 AD/AS 293894
Under cylinder 1&2: 13 11 (or IL?) 1602
Under cylinder 3&4: 10 11 6 1601 601 A
Near flywheel: 50M and 24

 

[Happystamps]

it should be written on the side of the crankcase, under one of the cylinders. Most cases are AS41 (Some magnesium), some are AS21 (little bit less magnesium), some replacement cases are pure aluminium.
That's your problem- most welders don't want to touch mag, and either way you may have a problem finding filler material. I've heard of people using slivers cut from scrap cases before, might be worth suggesting if you find someone.

 

[gvee]

Added a few more numbers to my previous post...

 

[gvee]

Took the engine to a fabricators near where I live and they're going to sort me out. Totally unphased about the material, be it ali or an alloy as "this is [their] bread and butter".

Gave them the a couple of pressure senders and the T-piece I was using today so the chap can make something up out of a "spare" block of aluminium which will screw in to the case as a bit of an extension piece and allow the pieces to still be fitted.

They're exceptionally busy at the moment but they're being proper awesome and the young lad is going to stay on after hours tomorrow to weld it all up.

<link removed>

 

[Happystamps]

If they think it's made of bread and butter you might have a problem.
Are you sure you took it to a "fabricators", not a "delicatessen"?

 

[jerupke]

Friend of mine had tge same problem, went to a welder, did not work. In tge end the company tried every kind of welding, to no result.
In the end we glued in a helicoil and it has been running ever since (approx 20k)

 

[gvee]

If they think it's made of bread and butter you might have a problem.
Are you sure you took it to a "fabricators", not a "delicatessen"?

Friend of mine had tge same problem, went to a welder, did not work. In tge end the company tried every kind of welding, to no result.
In the end we glued in a helicoil and it has been running ever since (approx 20k)

Glued?
More details please!

 

[Zcat7]

I was thinking that JB Weld or epoxy might be a solution to set a new mount/helicoil into the existing hole.

 

[K@rlos]

Cases are prone to this. When we built my motor I had the area built up with weld to be stronger. Not pretty but it stops the case cracking.

 

[jerupke]

I will ask him what glue he used

 

[gvee]

Was let down by the engineering company for a second time so following advice of a local spares place I have used QuickSteel for a not-so-pretty-buy-hopefully-effective fix.

I have also bonded the T-piece in to the case, which is probably overkill, but the last thing I want is to have to do this again.

Fingers crossed.

 

[Trikky2]

That looks very neat. Nice work. Fingers crossed it holds for you.

 

[drmuddle]

I did exactly the same and yes it is tapered. I tried every possible option but in the end I had to change the casing. Every welder told me the case was made of monkey metal! Nice. I was devastated! This was on my 73 bus.

 

[gvee]

Update time...

Ran the engine in on Sunday. There was a small leak from this repair.
It appeared to stop before the end of running things in. Father suggested that the case might have expanded with the heat?

I believe I have spotted the troublesome area and added more QuikSteel. It was on the underside of the repair, the hardest bit to see/access... naturally :roll:

Should find out tonight if that has resolved the drip :msn4:

 

[Zcat7]

I used high heat JB Weld to try to repair a major crack near the oil cooler mount and it lasted until the engine got really hot then let go. It was always a bit of a long shot but I would imagine that there is little scope for movement and flex in the oil pressure switch area compared to the cooler mount so I imagine that it should work. Fingers crossed for you mate!