Flyingfish wrote:
It is quite possible that an external cause is there.
Highly unlikely unless your mags have been timed by an imbécile.
Flyingfish wrote:
only option in stock is ECI and I don’t want them
And why is that ?
Flyingfish wrote:
The coolant was getting hotter and hotter (yellow arc)
Isn’t the coolant temperature gauge located after the radiator? If the coolant temperature was increasing, then the coolant was circulating and the pump is probably not the cause me thinks… Is there a thermostat that restricts circulation until the engine has warmed up that could be blocked shut?
@Aviathor: “Is there a thermostat that restricts circulation until the engine has warmed up that could be blocked shut?”
Actually there is one (as in a car engine) – but why would ONE cylinder go hot while the others are perfectly happy.
The theory with the coolant pump is:
We are losing cylinders 5 and 6 which are in the front and are the last ones served by the coolant flow.
The coolant setup is such that cylinders 1,3,5 are cooled in this sequence (in series, so to speak) and another (parallel) circuit is serving cylinders 2,4,6 in another series.
If the pump is misbehaving, maybe it is not “pushing” the coolant through the last cylinders of each circuit, i.e. cylinders 5 and 6?
@Michael the timing of the mags has been checked early on – no findings.
@ all: Can you think of something in the BOTTOM end (crankshaft, bearings…) that could cause pistons 5 and 6 to lose alignment and start grinding into the barrel? The fact that until now the problem is at the frond end of the cylinder array could support that.
The crankshaft has been repaired (eliminated light pitting, balanced, nitrided)
The camshaft is new (from RAM with a different valve timing supposed to improve performance).
Flyingfish wrote:
cause pistons 5 and 6 to lose alignment and start grinding into the barrel? The fact that until now the problem is at the frond end of the cylinder array could support that.
This is just plain nuts. Send the engine back to the builder for re-work under Warranty.
Stepping back a bit:
1) Did the engine loose coolant? If so, how much?
2) Do you definitely know that the cylinder cracked and then lost coolant, not the other way around?
Data logging of coolant system pressure would be really useful here, commonly used in race car engines.
Michael wrote:
This is just plain nuts. Send the engine back to the builder for re-work under Warranty.
Michael, removing / reinstalling and shipping back and forth is very expensive (> 10 K Euro) – last resort.
ortac – not much coolant, no visible drop in level. It cracked first and lost coolant (into cylinder) next.
Flyingfish wrote:
removing / reinstalling and shipping back and forth is very expensive (> 10 K Euro) – last resort.
That may be the case, but even the smallest defects in the bottom end should not be tolerated, period.
I cannot even fathom something sooo wrong that it’s causing the pistons to “grind” the barrels
To be honest, none of this makes any sense whatsoever.
Flyingfish wrote:
no visible drop in level.
lost coolant (into cylinder)
How can you know that it lost coolant if there is no visible drop in coolant level? And how can you know, even if it definitely did lose coolant, that it lost it via the crack and into the cylinder / combustion chamber? I don’t understand how you have jumped to this conclusion.
Flyingfish wrote:
Michael, removing / reinstalling and shipping back and forth is very expensive (> 10 K Euro) – last resort.
That may be the case but it really looks like someone has goofed massively on this engine. And whoever that was has to take the full cost of whatever happens. That is what warranty is for.
If a newly done engine behaves like this and on top you find out that key components such as the coolant pump have NOT been done as it was claimed, then a lot more can be wrong. I think that in the end, a complete re-overhaul or replacement of this engine will be the best solution.
Michael: at this point we have absolutely no hint of a defect at the bottom end – My question: "Can you think of something in the BOTTOM end (crankshaft, bearings…) was meant to ask for “creative” thinking or own experience with cylinder problems having their cause in the bottom end.
To all: thanks for your contributions. It looks like this discussion has had the unwanted effect of making the whole thing look more dramatic than it may be.
Just as a reminder: the engine was running very smoothly and making normal power between the cylinder failures.
At this point I’d like to wait for the report back on the condition of the pump. Thanks for your understanding.
