… or as I heard someone say, many years ago… “All I know is that if I put gas in it, it goes”.
If I was repairing or replacing an interference engine which had interfered, I’d have the machine shop order a set of custom pistons and connecting rods, which lower the maximum travel below the maximum valve opening, plus some margin of error for thermal expansion. Next time the timing belt fails, it will be worry-free.
But, that would lower the compression ratio and reduce the power output.
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I’d be raising the compression and making more HP… lol
I’d think if you asked a machine shop to lower the compression on an otherwise stock engine that they would look at you cross-eyed… I hate to even see what that would even cost…
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Additionally, reducing the power output of that tiny engine would likely make it a hazard on the entry ramp of a superhighway.
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I know I need to decide now whether to pay to repair or scrap I think I will see what quote I get for the new engine and then make a decision from there.
The suggestion the garage could contribute to fixing it (if their error) was something I had considered but I didn’t want to suggest this to them before first of all getting opinions on here as if this is our fault and not there’s I wouldn’t even mention it to them and I of course would then foot all the cost.
Thanks everyone for your input I think I’ve established the garage shouldn’t have turned the engine on but that I also should have got the car seen to quicker so were both somewhat at fault.
I think for now I will await this quote and then make any further decisions from there.
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Just as a consumer and not a mechanic, while I think it was unwise for the shop to start the car, you will need to explain what the rattling noise was when it first stalled? Likely those were the valves being bent from the pistons. The damage was done. Now you want to blame someone else?
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No they’re not.
I can’t tell you how many timing chains I’ve replaced over the years either because the timing chain was stretched or the timing chain guides failed.
And some of these failures caused major engine damage.
Tester
Or just have a machine shop mill some valve reliefs into the tops of the pistons. As far as I know, that can be done, and it’s what makes a lot (all?) of non-interfence designs non-interference.
Dished pistons for standard compression (8.5:1ish) mostly
Is the car solid or already heavily rusted?
The oil pump drive belt may have broken first, operating the engine without oil pressure will damage the crankshaft bearings and cause engine noise. Or the timing belt particles were blocking the oil pump pick-up screen and caused the loss of oil pressure. For some reason they wanted to replace the oil pump, but the damage was already done.
With no oil pressure, the camshaft will eventually seize and cause the cam belt to break but the damage to the crankshaft was already done, a tear down of the engine would have proved the engine to be beyond repair.
What are the timing belt service intervals? The North American models show 150,000 miles in the maintenance guide.
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… or, every 10 years, whichever comes first.
It appears that this Focus is 12 years old.
It’s pretty optimistic to place all those particular items in the “every 150000 miles” category, imo
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Re: Should it have happened?
I’m a diy’er & visually inspect my Corolla’s dry timing belt every 30K miles for any signs of deterioration. Relatively easy to do. If I noticed any problems w/the timing belt I wouldn’t even start the engine, let alone try to drive it.
In your case though, given the engine’s wet-timing belt, which probably isn’t easy to inspect, and presumably you aren’t a diy’er, I’d give the shop a pass. Unless you asked them to not start the engine, they were doing the best they could. There wasn’t any easy way for them to know the timing belt was about to break. Just b/c the rubber is deteriorating doesn’t mean the belt is about to break. In most cases there would have been no problem. .You just got unlucky is all.
And a replacement engine comes with certain benefits. For example, suggest to ask the shop to visually inspect the replacement engine’s timing belt, and if any signs of deterioration, ask them to replace it before installing the engine. It’s probably much easier to replace w/the engine not installed. Another upside, you have the option to replace the next timing belt more frequently. Best of luck.
Once you get the car w/replacement engine back, make sure there are no diagnostic codes and all the emissions readiness monitors are in the “complete” state.
Some suppliers of used engines require the installer to replace the timing belt, water pump, thermostat and rear crankshaft seal.
Reading this leads me to believe Nevada’s analysis above is likely what happened, (oil pump drive belt breaking first leading to damaging the engine).
Ford did issue a recall for newer Ford Focus models (2016-2022) for premature engine oil pump drive belt or tensioner failure. In the recall, Ford offers to replace the engine.
OP’s is a 2012…
Could you also grind the cam lobes down so the valves don’t open as far?