gumby's '79 X-1/9

May need to do some basic engine setup / timing checks just to get a sense of what happened. Have you tried rotating the motor CCW? Get the timing covers off & see if there is evidence of stripped belt teeth, sheared cam pin, etc... Even if the piston smacked the valves, it should still go CCW away from the event, unless something else locked the crank (bent a rod, locked against the block?). With the t belt off, you can gently try rotating crank and the cam independently. Probably worth dropping the pan to look for chunks of piston, metal shards in the oil pick screen, etc. Since it was a low mileage rebuild, hopefully the damage is limited to the one cylinder & you can get away with minimal work. If the crank is locked solid both ways even with the belt off it doesn't really sound good at all though.

Could easily go from just needing head work, to block (resleeve) & rotating gear if a bore is significantly damaged..
 
I was next in line behind you to get this X. If your plans change, give me a call :)

I recently picked this 1974 X1/9 up from California. One owner rust free car with original paint. Been in his garage since 1984. The battery was dated 1981!

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Here is the plug from no.1
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So, we had a date with the bore scope tonight.
Starting from number 4 to get an idea what things are supposed to look like, we didn't get a good pic. I think the piston was all the way up and the camera just wouldn't focus

Number 3 looked normal
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Here is #2, looks like some possible PTV contact
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And #1, JUNKED
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The camera body wouldn't fit past what appears to be an upside down valve, so it is difficult to say what is beyond it in the pic here, but it doesn't look pretty. End of the rod? Broken piston parts?

Doesn't really matter at this point. Gonna move the spare motor into the shop and look it over next. Roll it over and leak it down to make sure I am not wasting time installing another junk engine.
 
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Since this car and PO are known around here, does anyone know who Mike bought the spare engine from? I am looking for a bit of history on it if it is available.
The info I have been given is that it has forged Probe pistons and may have bigger valves in the head. I can see new pistons thru the spark plug holes, double valve springs, clean ports and valves(maybe new), and that it was never started after assembly. There is still assembly lube in the head, and the sealing washers on the plugs have not even been crushed.

I do not know how long ago Mike purchased the engine, nor who put it together. It rolls freely, and builds compression as pistons come up to TDC. There is no cam box on the head, so all valves are closed. I am debating tearing it down to inspect everything so as not to have a valve smashing re-occurrence.
 
Diving into the broken motor. I can get used to this mid-engine deal with a built in work bench!
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One of these things is not like the others!
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Now, on the end of this cam there is A-411 engraved. I'm hoping I can use that to figure out what cam this is?




And a couple random shots of the spare engine
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You will want to freshen that motor. Water pump, crank, cam and aux shaft seals. New timing belt and tensioner pulley obviously. And, as you probably already could tell, that side motor mount is junk.
 
Pic for future reference
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Carnage pics
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Lots of broken pieces in #1, and the HG was pushed out too.

#2
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Valve contact marks, and a bent valve.

This gasket match-up doesn't look right either
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So then I played a bit of musical engines in the parts dept to free up a stand. I could see some sharp edges in the valve reliefs of the spare engine that need to be dressed down and I have decided it is worth eating the cost of gaskets to know that it went together correctly and isn't another valve eater.
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Here are the guts of the new "spare" engine

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Bottom side is just as pretty. Balancing marks abound
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The pop-up portion of these pistons is roughly .125" tall. I am going to re-measure everything and try to make a determination, but any guesses what the static CR might be?
 
Has it been determined what caused the damage to begin with?

At least your back-up engine looks good inside (at first I wasn't so sure just judging by the appearance of the out-side). Was it done by the same builder as the first engine? Like you, I'd certainly hate to see the same thing happen for the same reason (which is why I wonder the cause of the failure).
 
I don't know which came first, chicken or egg.
The builder of the first engine was the PO of the car.
I too assumed the spare engine was simply a take-out. Not sure why someone would do or have done this much work and not paint the outside of the block. It is my understanding that this engine was purchased complete from another X1/9 enthusiast.
 
gumby23 said:
It is my understanding that this engine was purchased complete from another X1/9 enthusiast.
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That could help reduce the chance of a similar failure; for example if a bad batch of valves had unknowingly been purchased and used in both engines, then it could do the same. But not likely if from two sources. I agree, it is odd to let the outside get so rusty on a newly built engine. It almost looks like it was submerged under water, but no signs of water internally (that i noticed in the pics).

Its a 1500 (non-interference) so not timing belt related. Could have been a retainer failure, just a faulty valve stem, or possibly the guide got too tight with heat? Although did you say another cylinder also has damage from the valve touching the piston? Maybe there isn't quite enough valve clearance to the pistons and too soft of springs, allowing float at higher RPM's?
 
1500cc engines are interference free when stock. But hi-comp pistons and shaved head could change that. Don't ask me how I know.
 
Good point Daniel. I guess that would be related to the thought: "Maybe there isn't quite enough valve clearance to the pistons and too soft of springs, allowing float at higher RPM's?"

Gumby, you might have covered these questions already. Was there a timing belt issue? And is it a heavily shaved head? Just eyeing the photos above the head does appear to be shaved a bit (recesses appear shallower).
 
I have no way to know if it was caused by a timing belt slip as I could not roll the motor over to check the timing without disassembly. I can say the belt looks fine. The head is shaved; my forum sleuthing says probably .060"
Piecing together a rough timeline overlaid with the parts on hand vs. pics in threads, this engine was built in 2012 after an attempted rebuild of the original engine resulted in smoke and oil consumption. Between 2012 and 2014 there are a handful of topics not engine related that lead me to believe this engine was doing fine. There is complete radio silence from 2014 thru 2017, at which point the car was listed for sale as reliable and ready to go. Was the car fine thru the whole black-out? Was it parked? The engine looks well run, more than 800miles I'd guess.
The 2017 sale was immediately prior to a scheduled back surgery. Having exchanged many emails with Mike, I knew if the car did not sell it was slated for storage until he would be physically capable to get back to it. I also know that before the surgery/storage the car was taken out for a drive, and **** hit the fan. The car was later relisted at a reduced price with the resultant engine damage.
I believe this was an acute failure caused by either a slipped adjustable cam gear or a big over-rev(missed shift?), combined with the reduced clearances of a big cam, shaved head, and small relief pistons.
 
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Fiataccompli said:
Which adjustable cam gear did it have?
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Miller's Mule adjustable cam gear


I am holding off on ordering any gaskets until all the measurements are complete. I want to get an idea of static CR before I commit to a HG thickness. Same goes for the cam box gasket; I need to check lash and inventory all my shims before deciding on a thick or thin gasket there. Broken engine was thin, new engine was thick.

Looking at pictures on the MWB site, it appears the broken engine had a 14-bolt HG. Both of these engines are 10-bolt versions. The locating dowels were also MIA. I found them in the stock head. I imagine the HG mismatch and missing dowels played part in the leaky HG situation evidenced on the gasket.

I probably need to call MWB and find out if there are any differences between the carb and FI gasket kits beyond the intake manifold and ancillaries. Looking at some write-ups on here, it appears the new engine has a FI water pump, housing, and pipe. I am not sure if any of this should affect my gasket choices just yet.

The "while it's apart" list is growing as well.
I broke the frunk lid cable day1, and popped the trunk cable yesterday. Better get those. I need to learn these levers have more travel than the latches they are connected to!
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Also, the shifter has quite a bit of slop. I disassembled it today. Slop at the connection to the linkage, as well as slop in the center pivot. I don't see any rebuild parts for the shifter itself on MWB. What options are available to tighten this thing up?

Is there anyone recurving distributors for these engines?
 
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The original engine could have been over-rev'ed and caused a nic'ed valve and thus the failure. Assuming the belt was intact and the timing accurate that's what I would assume. Valve failures from healthy valvetrains are very rare.

The hi-comp pistons from the second engine are similar to others I have seen. My guess would be 12:1 compression. Clearly, somebody put some time and effort into building the engine. A balanced crankshaft and high compression, forged pistons would tell me there is likely an upgraded camshaft as well. Have the ports been worked?
 
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