Oil dump from top end on fresh rebuild - Thoughts?

[17alloveragain]

So, I'm less than 1k miles off a fresh, comprehensive rebuild. Everything was running great and clean. There were no leaks, and no indications of anything wrong. Until Friday.

Going uphill at freeway speed, spinning at about 4k RPM, temp good, oil pressure good (I just looked at both), smoke started coming from under the hood, looking behind to make my way off the freeway there was a huge cloud of smoke behind me. As I got to the shoulder, the oil gauge still showed good pressure, and the engine was not making any noises at idle, so I thought it must be a gas fire, and it was the end of the Spider. I shut down, jumped out and started to call 911, but the smoke started to dissipate.

After a few minutes, I popped the hood, and oil was everywhere, even pooled around the no. 1 plug. It seemed like it was coming from the exhaust side, but I can't be sure. I haven't run it since getting it towed home.

I can't tell where it came from. My guesses are (in order of "f my life"): (1) front exhaust cam seal failure, (2) front main seal going bad and oil riding up the timing belt, or (3) something internally went very bad (total ring failure/hole in a piston) allowing blow by to blow the oil and blow by forcing it through the filler cap. I am going to do a compression test, but I'm almost afraid to turn it over - really I guess I'm more afraid that it is no. 3 and it's back to the drawing board.

Thoughts?

[ORFORD2004]

It happen to me once, i forgot to put back the oil cap... Drive 1/2 mile and i look like cheech and chong up in smoke. Oil everywhere. Clean your mess with engine degreaser, fill your oil and start the car to find the leak.

[18Fiatsandcounting]

I wouldn't assume the worst. Oil leaking onto a hot exhaust manifold looks pretty dramatic, but while not harmless, the cause should be fairly easy to determine by cleaning the engine and running it again. It could be something as simple as an issue with the oil fill cap as Orford suggested. Check also that your dipstick tube isn't leaking, but I kinda doubt this since the oil leaks appears to be on the exhaust side.

Another possibility is that one of your exhaust manifold to head bolts/studs came out. The two top ones (#2 and #4) out of the 5 go directly into an area where oil pools up, so if one of those fell out, oil will come streaming onto the exhaust manifold. Another source of leaks is the distributor base gasket or internal seal, but these usually result in slow drips rather than large amounts of oil.

So give it a visual inspection, and if nothing seems amiss, clean the engine off (in particular the exhaust manifold) and start it up. I doubt at this point that you have anything internally going on. Oil leaking into the combustion chamber will be burned and so the only evidence you'd see is greasy blue smoke from the tailpipe. External oil leaks are usually a gasket, seal, or missing bolt issue. Or an issue with the dipstick or oil fill cap as mentioned.

-Bryan

[17alloveragain]

It happen to me once, i forgot to put back the oil cap... Drive 1/2 mile and i look like cheech and chong up in smoke. Oil everywhere. Clean your mess with engine degreaser, fill your oil and start the car to find the leak.

LOL at up in smoke! That is EXACTLY what it looked like!

[17alloveragain]

Thanks guys. I've got it cleaned up, and this weekend, I'm going to fill it with oil, run a compression test just for peace of mind and, if things look good there, will fire it up and see if I can find where things went "up in smoke." I'll post what comes of that!

[17alloveragain]

Update.

Bad news.

I topped off the oil and fired it up. It seemed to run fine, and came up to temp with good oil pressure. There were no visible leaks. I ran a compression test, and it read 125 on all four. I put the plugs back in, fired it up, and it ran fine for a minute or two. Then it made an audible "tick" and started knocking badly.

I am perplexed, though, why it would happen that way. Could it be that the oil blow-out starved it of oil, and a bearing that was ready to go let loose after a warm up, cool down cycle?

Absolutely heart-broken.

[18Fiatsandcounting]

Where are you located?

Again, I wouldn't assume the worse. Engines usually don't run fine one moment and then suddenly crap out. A few possibilities:

1) Your auxiliary shaft pulley is timed wrong, and the lobe on the aux. shaft is hitting the #2 connecting rod once the engine warms up.

2) You've got an incorrect tappet clearance on one (or more) of the valves and that tappet(s) get(s) noisy when warmed up.

3) The engine is desperately in need of an oil change using the right oil and filter. Has the oil been changed after the rebuild? 10W-40 or ?

All of these are easily fixable. There are other possibilities, but it's hard to say based on what you've told us.

-Bryan

[17alloveragain]

Thanks Bryan!

I am in Orange County, CA.

I changed the oil about 100 miles ago to 10w-40 conventional after about 400 miles on the break-in oil.

I'll check the aux. shaft timing (the one I had when I was 17 had that happen) and do another oil change and see how it looks.

Let me know if there is anything else I could tell you that might help with figuring out what to do next. I really appreciate the replies, advice and positivity!

All the best,

Sean

[18Fiatsandcounting]

Sean, can you describe the "knocking"? That would help us narrow down the possibilities. Is it knocking like a 1972 AMC Pacer on bad, very low octane gas? As in pinging? Or a deeper knock in the engine? Only at idle, or only when you rev it, or all the time? It's not something rattling against the engine like a loose timing belt cover, alternator mount, radiator, etc? With the engine off, feel around on the engine and see if anything feels loose.

You mentioned the engine was rebuilt. Can you describe what was done?

A few possibilities:
1) Your ignition timing slipped, and it's too far advanced so it's truly knocking as in detonation, pinging, etc.

2) It doesn't sound like you ran out of oil, so I'm not thinking it's something like rod knock, but maybe.

3) Piston slap? Usually more of an issue with cold engines, but if the pistons are too loose in the bore, especially at the top, they will "slap" from one side to another as they rise to TDC and then start the downward motion. Unusual in a Fiat, but I suppose it could happen.

4) Bad alternator bearings, or a bad water pump (either bearings or the impeller is knocking the side of the block as it spins).

-Bryan

[17alloveragain]

Hi again, Bryan.

It sounds like metal beating on metal, relatively fast, and is at idle and mild revs. I do not, however, hear it spinning the engine with just the starter. Everything external is tight, and it does not appear to be external. It's pretty loud and jarring and the engine seems to be stumbling, so I don't run it long, which does make it a bit difficult to pin, but as best I can tell it is driver's side, lower end.

The engine rebuild was comprehensive. It started to address multiple oil leaks, but on disassembly, cylinders 2 and 3 had some scoring, so it got a bore to .6mm over, so new pistons, rings, bearings, crank was good/no machining, wrist pin bushings. Head, valves and cams were gone over and cleaned, adjusted, no machining or milling was needed. Internally, it also got a new oil pump. All gaskets and seals replaced with new. Externally, it got new: water pump, fuel pump, smog pump, sending units, thermostat, mounts, timing belt, timing belt pulleys, timing belt tensioner, clutch, hoses. Unrelated to the engine, the trans was gone over and was found to be fine, it got new gaskets seals. Same for the rear end, and all suspension bushings were replaced.

Here is what I did for further exploration today: oil and filter change, no sparkles in the oil; another compression test, same 125 across all 4; checked plugs, look fine; the timing belt still had a little oil residue on it. I am thinking maybe (hopefully?) the oil dumped all over the belt caused the aux shaft timing to slip? But since I don't hear it spinning with the starter, I am only cautiously optimistic. I haven't pulled the timing cover off yet to check that, but it is next. I'll also check the ignition timing. I'll post an update.

I can't thank you enough for your time and advice, Bryan. I really appreciate it.

Sean

[18Fiatsandcounting]

This is helpful, thanks. Well, it is beginning to sound like something isn't quite right internally, and it could be something was missed when doing the rebuild. Like a rod cap was put on backwards and it spun a rod bearing.

But before diving into the engine, I would check that your auxiliary shaft pulley didn't get mis-timed somehow. With the crankshaft at TDC on the #1 and #4 cylinders, and the camshaft pointers lined up, the timing mark on the aux. shaft pulley should be at about the 1 o'clock position when viewed from the front. It doesn't need to be exact; you just don't want it drastically off.

Did a repair shop pull the engine and rebuild it? If so, I'd talk to this shop.

-Bryan

[Pr124spider]

So sorry to hear. Hope you can figure it out and it is t too costly.

[17alloveragain]

Update:

I checked the aux shaft, and it is in time. Camshafts are in time as well.

Turning the motor over by hand produces a very tight spot with 1 and 4 at about TDC, when the pistons are changing direction.

Back to the shop that did the rebuild it goes....

Thanks for all the responses, advice and well wishes.

Sean

[18Fiatsandcounting]

Turning the motor over by hand produces a very tight spot with 1 and 4 at about TDC

Hmmm..... Very tight spot, like something is hitting? Or just gets harder to turn as you compress the air in the cylinders as the pistons reach TDC? This would also happen when pistons #2 and #3 reach TDC at 180 degrees later.

If you remove all 4 spark plugs and spin the motor by hand, or using the starter motor, it should spin freely around without any appreciable changes in resistance. I think you did this at one point but didn't hear any knocking. So, either something changed or something fairly odd is going on.

Any chance the pistons were installed backwards, so that the cutouts for the intake and exhaust valves are reversed? I have never done this, but it might be possible to have the intake valve hit the piston slightly if its cutout is not the right size. I would have thought that would have bent a valve, but your compression is OK (but not great). By the way, bending a valve usually doesn't result in a lot of noise, but the engine runs pretty poorly afterwards (if at all).

Odd. Keep us posted.

-Bryan

[17alloveragain]

Hi.

I should have added that spinning it by hand was with all the plugs out, and the "tight spot" is only at about TDC 1 and 4 - at around 5 degrees before TDC and only when the timing mark on the crank is in that position. It spins with slight resistance from that point all the way around until it gets back to that point. At that mark, the cam marks are lined up correctly, and the aux shaft is at 1 o'clock.

When it gets to that point, it almost feels like something is hitting, but I can't hear anything actually contacting anything or scraping past that point. I can turn it beyond that with effort, and it frees up again immediately after that spot.

I saw the engine before the head was put on, and the pistons were in correctly, with the larger reliefs on the intake side.

I am fighting every urge to take the head and pan off to explore further, but I don't really have the space or time to do that myself.

Thanks again!

Sean