![]() |
|
|
|
|
![]() |
|
LinkBack | Thread Tools | Rate Thread |
Author of "101 Projects"
|
![]()
On the right of this photo are the remains of what happens when a rod bolt fails (red arrow) in one of the later-style engines (1977-89 Turbo and 1984-1994 911). The rod bolt failed, and the end-cap of the rod twisted off. The rod then smashed a hole in the side of the engine case, basically destroying the entire engine. The photo on the upper left shows the carnage that resulted from the a valve head falling off of a 2.7L engine. It is theorized that the valve guides were so worn that they did not dissipate heat away from the head of the valve. This caused the head to snap and fall off. The two rods in the lower left are from the same engine.
![]() All of you with 1984-94 911s should look carefully at the frame on the right before over-revving your engine! -Wayne
__________________
Wayne R. Dempsey, Founder, Pelican Parts Inc., and Author of: 101 Projects for Your BMW 3-Series • 101 Projects for Your Porsche 911 • How to Rebuild & Modify Porsche 911 Engines • 101 Projects for Your Porsche Boxster & Cayman • 101 Projects for Your Porsche 996 / 997 • SPEED READ: Porsche 911 Check out our new site: Dempsey Motorsports |
||
![]() |
|
Senior Member
Join Date: Jan 2001
Location: Left Coast, Canada
Posts: 4,572
|
![]()
__________________
'81 SC Coupe "Blue Bomber" "Keep your eyes on the road, and your hands upon the wheel."- J.D.M. |
||
![]() |
|
Senior Member
Join Date: Nov 2000
Location: Great NorthWest
Posts: 3,944
|
Hey, I'm trying to EAT over here!
So how much are these test pilots paid to create these pics for you? Must be fun! John ![]()
__________________
'78 Targa in Minerva Blue |
||
![]() |
|
Registered
Join Date: Oct 2000
Location: Nor-Cal
Posts: 4,403
|
Disgusting
|
||
![]() |
|
Registered
|
![]()
Some day I will post a pic of an exhaust valve that came from a recent set of heads I rebuilt. The stem is truly in the shape of an "S". Needless to say, the remains of the valve guide were found in the muffler.
Good luck, David Duffield |
||
![]() |
|
Senior Member
Join Date: Apr 2002
Location: NY
Posts: 1,368
|
Here's one for you. A friend sent this to me recently. A little piece broke off the valve and rattled around in the cylinder causing the damage shown. This is from a stock 964 engine used in a racing (sustained high RPM) application. A rare failure?
|
||
![]() |
|
![]() |
Registered
Join Date: Jun 2000
Location: bottom left corner of the world
Posts: 22,741
|
Yeah, disgusting
![]() Bill 79SC |
||
![]() |
|
Registered
|
![]()
At least those rods got to lead a productive life ... even if short by 3.0 standards!
I remember a BMC 1275 cc racing engine for a H-Production Bugeyed Sprite in 1973 ... that lived less than two minutes, and the rods ended up in very similar shapes! The sound profile of that short run-in went like ... Vroom, vroom, rap, rap, rap, rap, rap, rap, rap, rap, rap, rap, RAP, RAP, RAP ... CLUNK!!! Owner/builder spent something like $1800 on rebuild parts and several weeks of rebuild time on Saturday afternoons/evenings with drinking buddies to put that engine together. I always wondered if it was beer or inexperience that contributed to that particular rod bolt failuer? Whether builder had ever had Briggs & Stratton experience is unknown ... but, six months prior he needed considerable assistance from yours truly to rebuild a pair of Zenith 32NDIX carbs from a '65 356C!
__________________
Warren Hall, Jr. 1973 911S Targa ... 'Annie' 1968 340S Barracuda ... 'Rolling Thunder' |
||
![]() |
|
Hilbilly Deluxe
|
John, that pic reminds me of the Miata guy who accidently dropped a bunch of BB's (yes, BB gun BB's) in his intake. I can't find the pictures, but there was a thread on it a while back.
Tom |
||
![]() |
|
Registered
Join Date: Jul 2000
Location: So. Calif.
Posts: 19,910
|
Does anyone have the pic of the cylinder head after the guy accidently deposited a package of bb's into the engine?
Sherwood Lee http://members.rennlist.org/911pcars |
||
![]() |
|
Hilbilly Deluxe
|
Sherwood,
I looked all over the place, I can't find them, even searched for every thread with "miata" in it, I don't see it anywhere. Hopefully Doug Zielke has it in his archives-o-doom. Tom |
||
![]() |
|
Registered
Join Date: Apr 2002
Location: Santa Clara, CA
Posts: 5,668
|
Wayne
For the dropped valve head on the left, how did two rods get twisted?
__________________
Chuck Moreland - elephantracing.com - vonnen.com |
||
![]() |
|
![]() |
Registered
Join Date: Jan 1999
Location: Roseville, CA
Posts: 393
|
__________________
'48 Willys CJ-2A / '55.1 Chevy 3600 / '66 Austin-Healey 3000 / '72 Porsche 911T |
||
![]() |
|
Team California
|
Tom, Probably a dumb question, but what was the guy doing holding loose BBs near the snorkle of his car while it was running?
![]()
__________________
Denis Trump uses an autopen and votes by mail, in case anyone wonders. ![]() |
||
![]() |
|
Registered
Join Date: Mar 1999
Location: Vancouver,Wa.
Posts: 4,457
|
As I recall, he did it on purpose (the bbs)......God only knows .......
A mans gotta' have a plan, I suppose. ![]()
__________________
JPIII Early Boxster |
||
![]() |
|
Registered
|
Gawd,...... someone please REPORT this thread!?!
This is worse than Wayne's cut hand. ![]()
__________________
Cheers, Sean. 94 911 Carrera 2 993 Cab http://www.pelicanparts.com/gallery/Sean_Hamilton |
||
![]() |
|
Unregistered
Join Date: Aug 2000
Location: a wretched hive of scum and villainy
Posts: 55,652
|
Those pictures bring back some bad memories.
Many years ago when I was young and stupid I built up a blown Chrysler hemi running 118 octane for a flatbottom drag boat. I spent every penny I had on the boat, and went into debt up to my ying yang. i guess i got a little carried away with the overdriving the blower pulleys. about 7 seconds into the run I heard a loud bang, the sound of my drive line ratcheting (a safety feature) and felt 16 quarts of motor oil running over my feet. Pretty much the same as the pictures above, a con rod stuck out the side of the block, holes in the donovan heads, etc. Talk about an expensive 1/4 mile. I was almost over the nightmares, now thanks to Wayne the therapy will have to continue :-) |
||
![]() |
|
Registered
|
The BB's go back to the old days of flathead engines.
The BB's were introduced slowly to de-carbon the cylinders. In days of old they were made of copper...not copper plated steel like today...that's the problem with old wives tales....the tale lives on long after the old wife has died!! LOL Old flatties had low compression..big chamber surfaces...and large valve openings (for their time)...so the trick mostly worked. The reason for using trick was that you were about to sell (or trade in) the car...other tricks were - heavier oil (quiet the knocks)...sawdust int the trans & rear end (quiet the cluncks)..sometimes banana skins in there too. Some of us old guys knew all the tricks...they worked long enough to sell the car...then it was your problem!!! LOL Bob
__________________
Bob Hutson |
||
![]() |
|
Hilbilly Deluxe
|
Thanks Boyo, that is it. For a description of what happened by the guy who owns the car, hit the link in Boyo's thread.
The short version is, engine apart to replace timing belt, intake sitting on workbench, BB speed loader of some sort sitting on top shelf, somehow fell of shelf and landed in intake. Drove for 2 days before loader came open. Klunk. Tom |
||
![]() |
|
Registered
Join Date: Jun 2002
Location: PNW
Posts: 2,753
|
Sick and wrong.
This is all just sick and wrong.
__________________
gary |
||
![]() |
|