cracked case
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cracked case
Recently I found a crack on my 2L engine case, where a stud screws directly into the magnesium. I really need some advice on how best to deal with it and prevent it becoming a serious problem. I could leave it, seal it or perhaps use JB weld, I just don't know.
I’m guessing to fix it properly would require an engine strip, but that may or may not be possible this year and be frighteningly expensive.
I’m guessing to fix it properly would require an engine strip, but that may or may not be possible this year and be frighteningly expensive.
1969 911E
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- Nurse, I think I need some assistance
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Re: cracked case
If you cant strip the engine to have it welded and tapped true after then if it isn't leaking oil I would leave it alone, but protect that crack from corrosion (which will make the welding so much harder later on) and JB would be a good material to use after really cleaning the area and the crack as deep as possible.
As it has cracked I presume there is a tread issue or over tightening responsible and you don't want that crak propagating further so a strip wilbe due soon.
Welding magnesium castings is a specialist job, but quite easy to find people to do this usually in the motorsport industry.
As it has cracked I presume there is a tread issue or over tightening responsible and you don't want that crak propagating further so a strip wilbe due soon.
Welding magnesium castings is a specialist job, but quite easy to find people to do this usually in the motorsport industry.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Re: cracked case
I suspected it had been over tightened, not by me but by someone who thought they were helping. For now I’ll give it a good clean and use the JB but, I guess I’m looking at a rebuild, something I was trying to avoid.
Thanks for your advice.
Thanks for your advice.
1969 911E
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- Put a fork in me, I'm done!
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Re: cracked case
Speak to Alan Barker from EMP engineering, they weld both aluminium and magnesium crankcases - he'll advise on best way forwards.
65 911 FIA race car
66 911 RHD restoration
67 911S LHD
74 911 Carrera 2.7 US Spec
79 Aistream Excella 28 MH
97 Bimota Vdue
14 KTM 690R Duke
83 RD350 YPVS
08 Ducati M900
00 Ducati 996SPS
944 T, 3.2 RSR, GT3 - SOLD
66 911 RHD restoration
67 911S LHD
74 911 Carrera 2.7 US Spec
79 Aistream Excella 28 MH
97 Bimota Vdue
14 KTM 690R Duke
83 RD350 YPVS
08 Ducati M900
00 Ducati 996SPS
944 T, 3.2 RSR, GT3 - SOLD
Re: cracked case
I can't actually see a crack in the photo ? ............ I see what looks like two casting "lines" - above and below threaded hole . Maybe just photo angle or my bad eyesight ??
If it's just a crack on the bottom - you MAY get away with an "in situ" spot of TIG (loosen bolt - good clean,weld and refit bolt to a lower torque ?) , to hold things together , untill you get opportunity to strip , fix properly and rebuild ??
If it's just a crack on the bottom - you MAY get away with an "in situ" spot of TIG (loosen bolt - good clean,weld and refit bolt to a lower torque ?) , to hold things together , untill you get opportunity to strip , fix properly and rebuild ??
Royal Enfield .. still in India
GL 1800 Tour DCT, for pleasure / Fantic 240 Professional - play
Rally 911 (1966) build parked for a while
Rally 928 (work started again - inc serious weight loss programe !)
.... and now another VW Up GTI owner.
GL 1800 Tour DCT, for pleasure / Fantic 240 Professional - play
Rally 911 (1966) build parked for a while
Rally 928 (work started again - inc serious weight loss programe !)
.... and now another VW Up GTI owner.
Re: cracked case
Yes, looks like that to me. Would need a photo of the other side of the raised casting line. Or even file off the casting line to get a better view?Cortina wrote:I can't actually see a crack in the photo ? ............ I see what looks like two casting "lines" - above and below threaded hole
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- Nurse, I think I need some assistance
- Posts: 18973
- Joined: Mon Mar 10, 2008 6:26 pm
- Location: West Midlands
Re: cracked case
Razor blade.
If you can get some in along the line...it's a crack.
If you can get some in along the line...it's a crack.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Re: cracked case
..... and even if you can't ..... it could still be a crack !!! (Razor blades go in straight lines ... sometimes cracks don't)911hillclimber wrote:Razor blade.
If you can get some in along the line...it's a crack.
Royal Enfield .. still in India
GL 1800 Tour DCT, for pleasure / Fantic 240 Professional - play
Rally 911 (1966) build parked for a while
Rally 928 (work started again - inc serious weight loss programe !)
.... and now another VW Up GTI owner.
GL 1800 Tour DCT, for pleasure / Fantic 240 Professional - play
Rally 911 (1966) build parked for a while
Rally 928 (work started again - inc serious weight loss programe !)
.... and now another VW Up GTI owner.
-
- Nurse, I think I need some assistance
- Posts: 18973
- Joined: Mon Mar 10, 2008 6:26 pm
- Location: West Midlands
Re: cracked case
OK, the corner of one!
Could be the casting flash 'line' but if oil tight I would leave it.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Re: cracked case
Thanks guys. I've made plans that will lead to a rebuild later this year, it was always on the cards. I'll keep an eye on this crack and if it gets worse I'll use JB weld to hold it.
1969 911E