The story of "the toy"

[Agnem]

What happened was simply the fullfilment of the prophecy which we all proclaimed. Everything has a cause and an effect. If you make one change, you tip the balance in one direction, and if you do nothing to compensate then equilibrium is lost and eventually death will ensue. You can see it everywhere... turn up the fuel - install a pyrometer.... open the intake - open up the exhaust... increase the boost - install head studs... and so on and so on. You cannot simply replace a govenor spring and run the snot out of it and change your motto to "it likes 4400 PRM" and expect that to be sufficient compensation. Too bad you never pulled the valve covers to at least check the springs. You might have seen the sludge, and started running AutoRx or something to clean it up. I bet even though you had good oil presure, there were parts of your engine where it wasn't good enough. A blocked passage down stream of the presure gauge is not going to effect the reading enough to tell you there is a problem. We will all be interested to hear what you see when you pull the pan and flip the engine over. One thing is certain.... we told you this would happen, and you failed to defeat conventional wisdom. I'm disappointed!

 

[DeepRoots]

i thought that were there is no combustion chamber in our heads that if the valves ever float then they would hit the pistons?

I thought you had the heads off?
What I mean to say is, how can you ask this question if you have the engine in pieces in front of you?

 

[nappy nate]

Heres a sketch of our prechamber I ran across somewhere, from the drawing it really makes no difference whether we have one or not when it comes to floating valves contacting pistons. Dyoung did you ever get that motor on a dyno? Are you installing the governer spring into the replacement motor right away ?nate

 

[oldmisterbill]

As Albert once said "for every action there is a reaction". I think this may help prove his theory.

 

[gatorman21218]

Imma go out on a limb here and say redlines and goveners are there for a reason. correct me if i'm wrong

 

[icanfixall]

In our motors the pistons pop up out of the cylinders as much as 31 thousands. Now a felpro head gasket is around 72 thousands crushed so... That leaves around 41 thousands clearance from the piston to head but wait........ All the valves are sunk into the heads too. The intake as much as much as 54 and the exhaust as much as 63 thousands....So add 63 to 41 and you have 104 thousands clearance at top dead center when the valves are..... Closed...... Where and when do you have float... Maybe at wide open valves and top dead center.... Surely you can see a hit... But like Calvin has already stated... Float does not mean you contacted a valve to a piston....... Glad all this is getting some expousre..... Not busting anyones chops either so don't get a rope yet.....

 

[dyoung14]

I thought you had the heads off?
What I mean to say is, how can you ask this question if you have the engine in pieces in front of you?

Yes the heads are off, all the pistons look perfect minus #2 which ate a glow plug tip, all the valves are perfect, the engine had the IP maxxed the hole time and the timing really high, not a single piston had any corrosion or even attempted to melt, when the engine made the rattle and smoke what towcat is saying is valve float it lasted long enough that i would think a piston would have hit a valve clearly not, maybe it didnt float maybe it did who knows cause i wasnt riding on top of the piston at the time

 

[dyoung14]

Heres a sketch of our prechamber I ran across somewhere, from the drawing it really makes no difference whether we have one or not when it comes to floating valves contacting pistons. Dyoung did you ever get that motor on a dyno? Are you installing the governer spring into the replacement motor right away ?nate

never had a chance to dyno, i hope to when i get the psd turbo and the other goodies i have for it on it
high rpm spring is in the only working pump i got, and its not working to well so it will be on it

 

[dyoung14]

In our motors the pistons pop up out of the cylinders as much as 31 thousands. Now a felpro head gasket is around 72 thousands crushed so... That leaves around 41 thousands clearance from the piston to head but wait........ All the valves are sunk into the heads too. The intake as much as much as 54 and the exhaust as much as 63 thousands....So add 63 to 41 and you have 104 thousands clearance at top dead center when the valves are..... Closed...... Where and when do you have float... Maybe at wide open valves and top dead center.... Surely you can see a hit... But like Calvin has already stated... Float does not mean you contacted a valve to a piston....... Glad all this is getting some expousre..... Not busting anyones chops either so don't get a rope yet.....

gary i always love to here your input and advice you are a waterfal of knowledge in the IDI world, you have never one time made me mad in any way, please continue to post interesting facts about this, and when im building my mean 7.3 in the near future i may have to ask alot of questions

 

[sle2115]

Valve float is a temporary thing...it's more of a bounce or multiple bounces from the spring not having the tension to keep them shut when it should. Just saying, it may not occur with the piston where it can make contact, then again, it could.

 

[sootman73]

I guess the question i have is what happens when the valves float? what are the concerns other than the piston and valves meeting? What damage can it cause?

 

[sle2115]

I guess the question i have is what happens when the valves float? what are the concerns other than the piston and valves meeting? What damage can it cause?

If no contact is made, generally none, continued floating though can cause seat damage, keepers to exit the retainer, etc. It's mainly a sign that you are working outside the limits of the engine and if you do it often enough, eventually the piston and valve will find true love and marry!

 

[SparkandFire]

If no contact is made, generally none, continued floating though can cause seat damage, keepers to exit the retainer, etc. It's mainly a sign that you are working outside the limits of the engine and if you do it often enough, eventually the piston and valve will find true love and marry!

Very well said!

If IH had designed these engines to rev above 3500 they would have governed it at that speed. At high rotational speeds all sorts of tolerances have to be considered, frequency harmonics and vibration are totally different at high speed. The torsional flex on the crank may become more than the damper can deal with. Nothing wrong with pushing the envelope from time to time, tho... As long as you have the time and money for it.

We have these extruder presses here that have a 7.5 HP motor that normally runs at 1750 RPM. We had a junk motor, and I was bored on a saturday (bad combination) I hooked it up to a 400 Hz drive and revved the motor up to about 7000 RPM It ran like that for about 30 seconds before it unwound! Sounded like a bomb went off, but it was a hell of a show from a safe distance.

 

[sootman73]

okay thats what i was thinking. thanks guys

 

[dyoung14]

My diagnosis: hydrolock while running because of to much either being sprayed into the intake then when the truck fired up it couldnt compress it all and bent the rod then shattered it into pieces then ran until it punched a hole in both sides of the block then finally coming to rest and locking the engine up, here is the rod, what do yall think?

Edit: i cant get the picture to post right now, for some odd reason, but when i get it i will post it, but it was a picture of the bent rod