'79 Olds 350, Engine knock?

g0thiac

G-Body Guru
Sep 6, 2020
852
93
Hi again.

So, as some of you might know I got my Delta 88 with REALLY bad oil. I was actually pretty mad, that someone would let an engine get this bad, but have no problem installing 3rd party gauges 🙄🤦‍♀️🤦‍♀️🤦‍♀️

Anyway, I did an oil change earlier this week, some Ck4 diesel and added MMO.

Within 30 seconds of it being ran, I noticed the engine noise went from being almost spread up front to now really from the left side, especially under the valve cover.


My mechanic who saw it at first, believes it might be a wrist pin tbfh. But that was before I did the oil change.

Should I start with rocker arms, and maybe push rods? I don't want to rebuild this engine, but I don't mind throwing $200-$300 if I can make it run at least for next year lmao?

Thanks, appreciate the help.

-Chris
 

79 USA 1

G-Body Guru
Sep 2, 2011
990
93
Cheektowaga, New York
Going out on a limb here Chris but in your video it sounds like an exhaust leak and if you look close at the manifold from the first cylinder on the bank (#2 of the 4,6,8, right side cylinder bank) there appears to be a crack (Thin black carbon line) in the manifold.
 
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g0thiac

G-Body Guru
Thread starter
Sep 6, 2020
852
93
Going out on a limb here Chris but in your video it sounds like an exhaust leak and if you look close at the manifold from the first cylinder on the bank (#2 of the 4,6,8, right side cylinder bank) there appears to be a crack (Thin black carbon line) in the manifold.
You might be right, I unplugged each spark, plug while running and no change.

Oil pressure is still decent. was going to do headers, have any recommendations?
 

79 USA 1

G-Body Guru
Sep 2, 2011
990
93
Cheektowaga, New York
Can you feel any exhaust pulses while holding your hand near the area? When it comes to headers on Oldsmobile engines I have to be honest...I draw a blank. Maybe one of our members versed in Olds engines will chime in. Also fitment into the B body Delta 88 maybe different from the A/G body unless using a universal set from Summit or Jegs. If it is a daily driver I would look for a cast iron manifold if that one is in fact cracked.
My knowledge of Oldsmobile engines was mainly the 394ci that I had in my 61 Olds Dynamic 88 Bubble top. Exhaust wise from experience with that car I know the left side Dual exhaust manifold from a 63 & 64 Olds 394 will fit and work quite well in a 61 & 62.
 
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g0thiac

G-Body Guru
Thread starter
Sep 6, 2020
852
93
Can you feel any exhaust pulses while holding your hand near the area? When it comes to headers on Oldsmobile engines I have to be honest...I draw a blank. Maybe one of our members versed in Olds engines will chime in. Also fitment into the B body Delta 88 maybe different from the A/G body unless using a universal set from Summit or Jegs. If it is a daily driver I would look for a cast iron manifold if that one is in fact cracked.
My knowledge of Oldsmobile engines was mainly the 394ci that I had in my 61 Olds Dynamic 88 Bubble top. Exhaust wise from experience with that car I know the left side Dual exhaust manifold from a 63 & 64 Olds 394 will fit and work quite well in a 61 & 62.

I do, specifically right here in both areas.

At low RPM's, it doesn't even sound that noticeable. Oil pressure is always between 20-40.
 

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g0thiac

G-Body Guru
Thread starter
Sep 6, 2020
852
93
Oh, I should make it clear the end of the video the noise seems to be different, but I don't remember actually that knock sound being any less also 🤷‍♀️😂😂😂

As I am concerned because when I was recording that, I heard some metal breaking, and the starter seems to be missing now, when I crank it sometimes, itll go JRRRRRRR and I have to try again.

Could the flex plate have been an issue?!

The oil filter had too several dents, I mean I want to hope it's exhaust.

But I also want to make sure it's not rocker arm, or timing chain related either as the oil was GARBAGE 🤦‍♀️😭😭😭
 

g0thiac

G-Body Guru
Thread starter
Sep 6, 2020
852
93
Can you feel any exhaust pulses while holding your hand near the area?
If what you describe in the video, as a pulse then definitely because I felt a leak in that area on both sides.
 

78Delta88

Master Mechanic
Supporting Member
May 23, 2022
437
63
SW Arizona
Chris;
Bad oil and engine noise, not a good combination.
I have several 307s if you need parts. If it's the crank the 307 crank will fit the 350. I have ext manifolds if you need them.
Headers are a little specific I have a custom cruiser wagon, so basically same setup under the hood as Delta 88 or Regency 98. I'll have to dig up the part number for you.
Eric
 
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g0thiac

G-Body Guru
Thread starter
Sep 6, 2020
852
93
Chris;
Bad oil and engine noise, not a good combination.
I have several 307s if you need parts. If it's the crank the 307 crank will fit the 350. I have ext manifolds if you need them.
Headers are a little specific I have a custom cruiser wagon, so basically same setup under the hood as Delta 88 or Regency 98. I'll have to dig up the part number for you.
Eric
Ok. Definitely need exhaust manifolds for sure.

If it's the crank I wouldn't bother man, I hear it's not worth saving a later 70's olds block, is that true? 🤷‍♀️🤣🤣🤣
 

gp471

Not-quite-so-new-guy
Jan 15, 2022
23
8
i thought these engine were notorios for the rocker arm pivots going bad.east fix
 
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