Changed oil & broke the engine

[Bianca1973]

Hello folks,
I’ve got a bit of a head scratcher for everyone.

I bought a 72 (originally thought it was a 73) 124 spider about 4 months ago. Replaced the front calipers, rebuilt the driveshaft and had the coolant flushed before bringing it from Redding Ca to Sf where I currently live.

Driving to and from work (about 4 miles daily) discovered that the charging system was weak, radiator fan was shot, and had the carb float needle housing unscrew itself resulting in carb flooding. Fixed all of those issues as they arose and was starting to comb through the rest of the car.

This weekend I changed the oil. Drained out some very dark, thick …oil, but didn’t see much in the way of metal particles. I then filled her up with Rotella 15w40 and went for a short drive.

The engine was significantly louder than before, sounded like a room full of typewriters. It seemed to rev a little quicker, and I wasn’t overly concerned as it sounded a lot like my bmw e30, only louder. I figured that the new oil had simply made it very apparent that I needed to adjust the valves. No problem, I ordered the full gasket kit and put the car away.

Yesterday, I was driving back from work, up a short hill and ‘Tackity-tackity-tackity-SMACK!’ The engine died immediately.

Now when I turn the engine over, it sounds like a pair of dice in a tin can. I will be taking the engine apart bit by bit this week, and was hoping for some suggestions on what to check first.

What I do know:
Both camshafts move correctly when turning the engine over.
Distributor shows no signs of damage.

Thanks in advance for your help.
David

[Nut124]

Was oil pressure good after the oil change?

Does the engine start and idle now? What does it sound like?

[Bianca1973]

Oil pressure was about the same~ 40 psi while driving after the change.
No engine does not start, starter will turn it over without too much straining but it sounds like a pair of dice being shaken around in a tin can.

[Bianca1973]

After a little more investigation, I discovered that the intake cam sprocket bolt had worked its way almost completely out. This caused the belt to jump a few teeth. I was really hoping it hadn’t damaged any valves, and put the sprocket back on, set the timing and installed a new belt. The car barely ran at all, so I have now removed and disassembled the head. Surprisingly only 1 valve was not seating correctly, but I ordered all new valves anyway.

After cleaning the head up, I noticed that most of the valve guides have tiny cracks in them- doesn’t look fresh, but I can’t say for certain.

Has anyone else come across this issue? I assume I will need to have them replaced & have ordered new guides from AR, should arrive this week.

I’m currently looking for a good machine shop in the SF Bay Area, any recommendations?

I’m also wondering what the scope of work will be- can I have them just remove & install new guides, or do the seats all need to be re-cut? Thinking I will require new shims after this as well.

Thanks for your thoughts,
David.

[18Fiatsandcounting]

I’m currently looking for a good machine shop in the SF Bay Area, any recommendations?

Yes. Send me a private message and we'll go from there. I'm in Livermore (East Bay).

-Bryan