predetonation?

[Quickstop [UK]]

I was driving the other day and put my foot down and only got to about 80kph when the car started shaking and vibrating quite badly.

It was quite disconcerting. Initially I thought I had lost a wheel balance weight but it got worse and worse and I began to think it was the road. I was very nervous and pulled over to see if it was a weight or if a wheel was flat. Nothing.

Could I have been having engine knock? What might have caused it?

thanks

Q

 

[bezerk]

Re: predetonation?

you are really asking for a engine rebuild.
didn't we told you already to get that wastegate working good, and wait till you can datalog with datamaster?

 

[Robert Lone]

Re: predetonation?

Did you PMCS or Pre-Flight your Ty before you put your foot in it???

It could be retreating blade stall...

You may want to practice auto-rotations for a while and then try it again. :2cents:

(dumb ole boys from SC know some stuff too :rotf: )

 

[Robert Lone]

Re: predetonation?

Seriously though, was it raining? Sounds like the symptoms you sometimes get when the ignition system breaks down. Just my :2cents:

 

[Flyin Ryan]

Re: predetonation?

If not ignition related and gets worse with higher speeds possibly the Propshaft is out of balance?

 

[bezerk]

Re: predetonation?

feulpump

 

[SEL777]

Re: predetonation?

Propshaft is out of balance?

X2. This is my guess. If the TRUCK is shaking at higher speeds. Or maybe an alignment issue.

 

[Quickstop [UK]]

Re: predetonation?

hmm...it stopped when I did and then never happened again...my poor truck

T-56 I was incipient vortex ring perhaps

 

[DynaGlide]

Re: predetonation?

Detonation feels more like a sputter than a shaking. Was it only under throttle? Was it just because you were driving at a certain speed? It could be a lot of things. We need more info to make our long-distance diagnosis.

 

[Quickstop [UK]]

Re: predetonation?

I am inclined to think mechanical rather than knock. It only happened at about 80 kmph and got worse and worse until I slowed down. It never happened at that speed before and has not happened since. It was really weird

 

[gkrcr882]

Re: predetonation?

something is definately out of balance, either the front propshaft, the rear driveshaft (unlikely), or something is on its way out in the front drivetrain somewhere. Might also want to check tire pressure and look for thrown weights as you previously mentioned.:2cents:

 

[Quickstop [UK]]

Re: predetonation?

dammit

 

[DynaGlide]

Re: predetonation?

Drive thru mud lately?

 

[Quickstop [UK]]

Re: predetonation?

Not that i am aware of. You thinking mud stuck on the rims causing imbalance?

 

[DynaGlide]

Re: predetonation?

It could very well be. All it takes is a little bit of mud settled in there to throw the balance off. I had a friend (cough, cough), who was borrowing a friends car, and got it stuck in the mud. When he got the car out of the mud, he noticed a shake immediately drove to the dealership to have an alignment done before I... er, he returned the car to his friend. When he got there, the mechanics told him that he had mud on the inside diameter of the wheel that was causing the shake. They then proceeded to laugh at this said friend, and send him on his way... thankfully without a bill.

 

[Flyin Ryan]

Re: predetonation?

It could very well be. All it takes is a little bit of mud settled in there to throw the balance off.

That reminds me of a classic movie "my cousin vinnie"

 

[berzerker]

Re: predetonation?

my ty did the same shudder / shaking when i lost a cylinder due to a broken rocker stud . might look into it alittle further then something out of balance. does the engine seem low on power ?