Diesel Runaway Description:
- Thread starter Darrin Tosh
- Start date
Depends on the engine, your screaming jimmies that you're always working on/with may not, but some of the smaller ones will easily pass 10K in a runaway. Remember some diesels run 6K+ on fuel.
trapper
Boom Boom
I have seen a detroit suck a nice perfect hole out of a clipboard, never skipped a beat, pieces camee right out the turbo, thich aluminum plate got her stopped.
rckslash2010
Registered User
I remember reading a post on here, or the other site, about a guy expirencing a runaway situation on his rig. He panicked and called 911. I could only imagine what was going through the operators mind when they received that call...
redmondjp
Full Access Member
This used to happen all the time with worn-out VW diesel engines back in the day - there would be so much blowby past worn rings and valve guide seals, and this of course was routed right into the intake manifold by design (no road draft tubes due to emissions laws). Once you got above a certain RPM, the engine would then run (away) on its own oil.
Smart people (or rather those who were aware of what was happening and knew what to do) kept the car in gear and braked it to a stop (I know somebody who actually ran their car into a wall at very low speed because the brakes wouldn't completely do the job), while others put the car in neutral and watched the engine grenade itself.
The later VW turbodiesels (including the TDIs) also have a potential runaway situation that is caused by ingesting a slug of oil that has accumulated inside of the intercooler. Apparently extended idling allows oil to leak past the laybrinth seal on the turbo shaft, and this oil builds up inside the intercooler (a small amount of oil always remains in there regardless). Once enough oil is in there and the airflow picks up a bit to draw this into the intake, watch out!
When I worked for a heavy truck manufacturer, we installed on any fuel tanker truck a system which mechanically shuts off the intake air if the engine RPM exceeded a certain value (usually set a couple hundred RPM above engine redline). This in case the truck was in an area with sufficient fuel vapors (such as from a large gasoline or propane leak) which could cause an engine runaway.
Fun stuff!
Smart people (or rather those who were aware of what was happening and knew what to do) kept the car in gear and braked it to a stop (I know somebody who actually ran their car into a wall at very low speed because the brakes wouldn't completely do the job), while others put the car in neutral and watched the engine grenade itself.
The later VW turbodiesels (including the TDIs) also have a potential runaway situation that is caused by ingesting a slug of oil that has accumulated inside of the intercooler. Apparently extended idling allows oil to leak past the laybrinth seal on the turbo shaft, and this oil builds up inside the intercooler (a small amount of oil always remains in there regardless). Once enough oil is in there and the airflow picks up a bit to draw this into the intake, watch out!
When I worked for a heavy truck manufacturer, we installed on any fuel tanker truck a system which mechanically shuts off the intake air if the engine RPM exceeded a certain value (usually set a couple hundred RPM above engine redline). This in case the truck was in an area with sufficient fuel vapors (such as from a large gasoline or propane leak) which could cause an engine runaway.
Fun stuff!
sootman73
Registered User
Exactly why I was taught that if we hit a gas line digging with a backhoe just run away. as soon as that engine grabs a whiff of gas its gonna run!
My friend had a quantum that would run away in nearly every gear, he said it was from an oil leak but i think it was bad sealing.
My friend had a quantum that would run away in nearly every gear, he said it was from an oil leak but i think it was bad sealing.
I play around with a bunch of the Volvos that use the larger VW industrial diesel ( high RPM diesels
and they had the same breather system, but I always upgrade them to the later style crankcase breather they had that had a little cap with a bit of internal baffeling to route the oil back into the valve coverIf you use dino oil on those things , the rings pack up and they will inhale insane amounts of oil in a fairly short period of time. Blowby would get mind boggling on the things. They were already running really low sulfur fuel in Europe when those things were built and they also had better oils , so in the us market we had crappier oils that had to deal with oodles more soot. Not a recipe for success . It's a wonder any of them survived.
Don't know if it was one of the links but the YouTube vid of the engine on the stand scattering parts is a good example of why I've resigned my self to briskly walk away in most run away situations. A run away is like a random variable fused grenade, you never know how long you got before it scatters.
flareside_thun
Reviving The General Tao
Killing a runaway is about the only thing a phonebook is good for anymore.
FordGuy100
Registered User
Newer TDI's have "anti shutter valves" that close during shutdown to help for a smooth shut down. Dont know if they will cure a runaway though.
redmondjp
Full Access Member
Yes, they will, IF they don't stick open
(engine is still shut off with the fuel solenoid on the IP, they added the mechanical air shutoff primarily to stop the "death rattle" shake that the engine made when turned off).Black dawg
Registered User
I had the 7.3 in my crewcab run away one morning. It was very loud and very scary. Getting away from it was my only reaction, never even tried to shut it down.
6.9poweredscout
Bleeds IH red...
my friend told me a story he heard of a 6-71 running away, it was sucking oil past the seals and took off, the guy working on it started throwing rags in the intake, the blower was making the noise of a wood chipper as it ate them, finally enough rags got packed into the cylinders it could no longer compress them and stopped. a full rebuild was in order to say the least!
scary incidents posted above!
Years back when the 6.0's first came out I was at a Dyno day event and a brand spanking new 6.0 that had all the latest and greatest power bolt ons with it. 2nd pull on the dyno and the turbo called it quits and it started drinking it's own oil. Watching those 20-30 guys that were in the shop at the time bolt out of there like lightning, you would have thought they were running towards the KMart blue light special on free beer or something. I never met the guy again that had that 6.0. Rumor has it Ferd warrantied it. I'm guessing the owner omitted key information like the power adders and that it was sitting on a dyno when she died.....
Years back when the 6.0's first came out I was at a Dyno day event and a brand spanking new 6.0 that had all the latest and greatest power bolt ons with it. 2nd pull on the dyno and the turbo called it quits and it started drinking it's own oil. Watching those 20-30 guys that were in the shop at the time bolt out of there like lightning, you would have thought they were running towards the KMart blue light special on free beer or something. I never met the guy again that had that 6.0. Rumor has it Ferd warrantied it. I'm guessing the owner omitted key information like the power adders and that it was sitting on a dyno when she died.....
