3,2 engine problem
yep
05-23-2014, 01:11 PM
#18
It's not just a matter of rebuilding the heads, the engine should come apart and be rebuilt.
The 3.2's have relatively weak rod bolts, due to their size, and typically stretch during such an over-rev. Another form of damage related, is that the rod ends can get "ovaled" when the over-revs hit and the bolts stretch, requiring the rods to be reconditioned. As part of the rebuild, one can use ARP rod bolts to beef up the bottom, and Ti valve spring retainers and racing valve springs to help keep down any high RPM "valve float" in the future.
Sorry, but your friend is looking at a rebuild.
The 3.2's have relatively weak rod bolts, due to their size, and typically stretch during such an over-rev. Another form of damage related, is that the rod ends can get "ovaled" when the over-revs hit and the bolts stretch, requiring the rods to be reconditioned. As part of the rebuild, one can use ARP rod bolts to beef up the bottom, and Ti valve spring retainers and racing valve springs to help keep down any high RPM "valve float" in the future.
Sorry, but your friend is looking at a rebuild.
His original plan was to localise the cylinders with lower comp, and just do the ones he finds with low compression.The engine is quite good the way I understand it, and he have threw 13 grand into the car uptil now in brakes, full repaint and lots of other bits and pieces, so this summer he was planning just to have fun with it, and now he`s a bit down.. When you say rod ends- you mean the big end right?
Cheers
Jørgen
05-23-2014, 01:26 PM
#19
Team Owner
Ed knows more than any of us unfortuantely the costs in repairing the money shift so i would heed his words carefully. I think your friend could possibly sink what he has put into his car over again to fix this .. and of course he is going to update the shifter after . Ed can probably tell you what to use for that too.
05-23-2014, 01:28 PM
#20
Rennlist Member
Yes, it's the big end. Truthfully, with rod bolt stretch and rod deformation, if your friend doesn't address it now, it could be ugly in the end.
Maybe Steve knows a way to do this in-situ. I believe it's entirely possible to remove rods without splitting the case, although probably not real easy. I used ARP rod bolts, and those check with a stretch gauge-I don't believe you can do that working through the spigot holes if you don't split the case.
Maybe Steve knows a way to do this in-situ. I believe it's entirely possible to remove rods without splitting the case, although probably not real easy. I used ARP rod bolts, and those check with a stretch gauge-I don't believe you can do that working through the spigot holes if you don't split the case.
05-23-2014, 01:30 PM
#21
Team Owner
Yes, it's the big end. Truthfully, with rod bolt stretch and rod deformation, if your friend doesn't address it now, it could be ugly in the end.
Maybe Steve knows a way to do this in-situ. I believe it's entirely possible to remove rods without splitting the case, although probably not real easy. I used ARP rod bolts, and those check with a stretch gauge-I don't believe you can do that working through the spigot holes if you don't split the case.
Maybe Steve knows a way to do this in-situ. I believe it's entirely possible to remove rods without splitting the case, although probably not real easy. I used ARP rod bolts, and those check with a stretch gauge-I don't believe you can do that working through the spigot holes if you don't split the case.
know any ?
05-23-2014, 01:37 PM
#23
Rennlist Member
When I did mine, I was redlined in third going for 4th, and hit second. I thought I caught it very quickly, but that was quickly proved wrong! I bent all of one side, and even spun some elephant foot retainer nuts off-they went into the motor, but thankfully, did no damage.
Seine Shifter, is a unit that adds a pseudo-gate to the 1-2 gear plane, thereby keeping 1-2 and 3-4 movements fairly separate, and avoid the same in the future.
It is simple, yet effective:
http://www.seinesystems.com/GateShift-1.htm
I thought I caught it very quickly, but that was quickly proved wrong! I bent all of one side, and even spun some elephant foot retainer nuts off-they went into the motor, but thankfully, did no damage.Seine Shifter, is a unit that adds a pseudo-gate to the 1-2 gear plane, thereby keeping 1-2 and 3-4 movements fairly separate, and avoid the same in the future.
It is simple, yet effective:
http://www.seinesystems.com/GateShift-1.htm
05-23-2014, 01:58 PM
#24
RL Technical Advisor
Maybe Steve knows a way to do this in-situ. I believe it's entirely possible to remove rods without splitting the case, although probably not real easy. I used ARP rod bolts, and those check with a stretch gauge-I don't believe you can do that working through the spigot holes if you don't split the case.
You cannot use the stretch gauge in the case, but you can measure stretch on the ARP bolts and the required torque on the bench so those values can be used during reassembly.
05-23-2014, 05:07 PM
#25
Yes, it's the big end. Truthfully, with rod bolt stretch and rod deformation, if your friend doesn't address it now, it could be ugly in the end.
Maybe Steve knows a way to do this in-situ. I believe it's entirely possible to remove rods without splitting the case, although probably not real easy. I used ARP rod bolts, and those check with a stretch gauge-I don't believe you can do that working through the spigot holes if you don't split the case.
Maybe Steve knows a way to do this in-situ. I believe it's entirely possible to remove rods without splitting the case, although probably not real easy. I used ARP rod bolts, and those check with a stretch gauge-I don't believe you can do that working through the spigot holes if you don't split the case.
Jørgen
05-23-2014, 06:41 PM
#26
Rennlist Member
Indeed, its quite possible to remove the rods from the crank without splitting the case; we've done this for 35+ years.
You cannot use the stretch gauge in the case, but you can measure stretch on the ARP bolts and the required torque on the bench so those values can be used during reassembly.
You cannot use the stretch gauge in the case, but you can measure stretch on the ARP bolts and the required torque on the bench so those values can be used during reassembly.
BEST!
Doyle
05-23-2014, 06:47 PM
#27
Rennlist Member
Sorry, no offence for not replying to your post! I have told him what you wrote, and he`s prepared
His original plan was to localise the cylinders with lower comp, and just do the ones he finds with low compression.The engine is quite good the way I understand it, and he have threw 13 grand into the car uptil now in brakes, full repaint and lots of other bits and pieces, so this summer he was planning just to have fun with it, and now he`s a bit down.. When you say rod ends- you mean the big end right?
Cheers
Jørgen
His original plan was to localise the cylinders with lower comp, and just do the ones he finds with low compression.The engine is quite good the way I understand it, and he have threw 13 grand into the car uptil now in brakes, full repaint and lots of other bits and pieces, so this summer he was planning just to have fun with it, and now he`s a bit down.. When you say rod ends- you mean the big end right?
Cheers
Jørgen
BEST to you!
Doyle
05-23-2014, 07:47 PM
#28
RL Technical Advisor
06-12-2014, 12:39 PM
#29
Part 2:
No luck so far finding anyone to do the disassembly/ assembly job, just a few who says yes, and then we cannot get in contact with them anymore..
So, we have decided to go ahead and do it ourselves, hence the following questions:
Are there any special tools needed for removing the heads?
Stretch bolts; do they HAVE to be changed?
Heads; do they need a surfacing job nevertheless?
Anything else?
I`ve had my head in quite some motorcycle engines through the years, but never a Porscheboxer, so I`m really hoping for some good advices here
Thanks in advance
Jørgen
No luck so far finding anyone to do the disassembly/ assembly job, just a few who says yes, and then we cannot get in contact with them anymore..
So, we have decided to go ahead and do it ourselves, hence the following questions:
Are there any special tools needed for removing the heads?
Stretch bolts; do they HAVE to be changed?
Heads; do they need a surfacing job nevertheless?
Anything else?
I`ve had my head in quite some motorcycle engines through the years, but never a Porscheboxer, so I`m really hoping for some good advices here
Thanks in advance
Jørgen
06-12-2014, 02:54 PM
#30
Team Owner
i think the special tool may be in gtting the cam nuts off while holding the cams.
I definitely suggest Wayne dempseys engine rebuilding book . Will give a ton of usefull information.
I definitely suggest Wayne dempseys engine rebuilding book . Will give a ton of usefull information.