Page 6 of 7

Re: Oil Smoke driving me crazy

Posted: Thu Jun 18, 2020 12:28 pm
by BillK
The main bearing looks like the clearance was too tight.

Something still does not look right to me on the oil ring. Can you take a picture aimed straight at the side of the piston instead of at an angle ? Mainly of the oil ring.

Re: Oil Smoke driving me crazy

Posted: Thu Jun 18, 2020 12:50 pm
by Belgian1979
Raybo wrote: Wed Jun 17, 2020 9:46 pm
BillK wrote: Wed Jun 17, 2020 9:06 pm
Raybo wrote: Wed Jun 17, 2020 5:26 pm E509C536-E731-45D8-86AC-62A9446555B2.jpeg
Pistons 1 and 2 didn’t show this. Almost all others did.
Hard to tell for sure by your picture but is there a support rail under the oil ring ? The scarring is usually from detonation.
Support rail is in place. Totally detonated. 10.5:1 on 93. Not sure what happend there.
Oil will make it detonate faster.

Re: Oil Smoke driving me crazy

Posted: Thu Jun 18, 2020 1:26 pm
by Raybo
BillK wrote: Thu Jun 18, 2020 12:28 pm The main bearing looks like the clearance was too tight.

Something still does not look right to me on the oil ring. Can you take a picture aimed straight at the side of the piston instead of at an angle ? Mainly of the oil ring.
.0035” .0040 on rear

Re: Oil Smoke driving me crazy

Posted: Thu Jun 18, 2020 1:27 pm
by Raybo
Belgian1979 wrote: Thu Jun 18, 2020 12:50 pm
Raybo wrote: Wed Jun 17, 2020 9:46 pm
BillK wrote: Wed Jun 17, 2020 9:06 pm

Hard to tell for sure by your picture but is there a support rail under the oil ring ? The scarring is usually from detonation.
Support rail is in place. Totally detonated. 10.5:1 on 93. Not sure what happend there.
Oil will make it detonate faster.
I’m trying to figure out what came first,oil or detonation

Re: Oil Smoke driving me crazy

Posted: Thu Jun 18, 2020 5:35 pm
by Raybo
C06ADC29-1FD3-49F2-B988-66E6CADFE14C.jpeg
BillK wrote: Thu Jun 18, 2020 12:28 pm The main bearing looks like the clearance was too tight.

Something still does not look right to me on the oil ring. Can you take a picture aimed straight at the side of the piston instead of at an angle ? Mainly of the oil ring.

Re: Oil Smoke driving me crazy

Posted: Thu Jun 18, 2020 9:05 pm
by BillK
Ok, Oil ring looks fine :) Must have been the angle in the other pic.

The main bearing looks like it is contacting almost 100% of the bearing diameter. Usually there is an area near the parting lines where the bearing is thinner and there is no contact. I think Clevite says it should be about 80% contact ? That's why it looks like there was not enough clearance. Still does not explain the oil issue.

Re: Oil Smoke driving me crazy

Posted: Thu Jun 18, 2020 10:42 pm
by Raybo
Bores have anywhere from .0005-.0010” egg shape. Some of the skirts on pistons collapsed too.

Re: Oil Smoke driving me crazy

Posted: Fri Jun 19, 2020 6:18 pm
by gmrocket
Raybo wrote: Thu Jun 18, 2020 10:42 pm Bores have anywhere from .0005-.0010” egg shape. Some of the skirts on pistons collapsed too.
Not enough clearance, it scuffed the skirts and pinched the oil ring.

Re: Oil Smoke driving me crazy

Posted: Fri Jun 19, 2020 10:48 pm
by MadBill
How do all the other bearings look?

Re: Oil Smoke driving me crazy

Posted: Sat Jun 20, 2020 11:47 pm
by Raybo
gmrocket wrote: Fri Jun 19, 2020 6:18 pm
Raybo wrote: Thu Jun 18, 2020 10:42 pm Bores have anywhere from .0005-.0010” egg shape. Some of the skirts on pistons collapsed too.
Not enough clearance, it scuffed the skirts and pinched the oil ring.
.0035” skirt clearance. Calls for .0025”-.0045

Re: Oil Smoke driving me crazy

Posted: Sat Jun 20, 2020 11:48 pm
by Raybo
MadBill wrote: Fri Jun 19, 2020 10:48 pm How do all the other bearings look?
Trashed at the back of engine. Progressively better as you get to 1,2 rods.

Re: Oil Smoke driving me crazy

Posted: Sat Jun 20, 2020 11:55 pm
by gmrocket
Raybo wrote: Sat Jun 20, 2020 11:47 pm
gmrocket wrote: Fri Jun 19, 2020 6:18 pm
Raybo wrote: Thu Jun 18, 2020 10:42 pm Bores have anywhere from .0005-.0010” egg shape. Some of the skirts on pistons collapsed too.
Not enough clearance, it scuffed the skirts and pinched the oil ring.
.0035” skirt clearance. Calls for .0025”-.0045
Maybe you had fuel wash on initial start up..they do look scuffed which will pinch oil ring first.

Fuel in the oil too by the looks of the bearings.

How did it start up, quick with minimal cranking and fuel?

Re: Oil Smoke driving me crazy

Posted: Sun Jun 21, 2020 11:08 pm
by Raybo
gmrocket wrote: Sat Jun 20, 2020 11:55 pm
Raybo wrote: Sat Jun 20, 2020 11:47 pm
gmrocket wrote: Fri Jun 19, 2020 6:18 pm

Not enough clearance, it scuffed the skirts and pinched the oil ring.
.0035” skirt clearance. Calls for .0025”-.0045
Maybe you had fuel wash on initial start up..they do look scuffed which will pinch oil ring first.

Fuel in the oil too by the looks of the bearings.

How did it start up, quick with minimal cranking and fuel?
Fired right up. I didn’t do my normal break in though. Since it has a roller cam I didn’t run it 20 minutes at 2500 RPM. Then I had to break the gears it before I really put it through the paces. Baddies it in the beginning.

Re: Oil Smoke driving me crazy

Posted: Mon Jun 22, 2020 3:27 am
by Belgian1979
Any chance that it's sucking oil through the rocker studs?

Re: Oil Smoke driving me crazy

Posted: Mon Jun 22, 2020 5:35 pm
by gmrocket
Raybo wrote: Sun Jun 21, 2020 11:08 pm
gmrocket wrote: Sat Jun 20, 2020 11:55 pm
Raybo wrote: Sat Jun 20, 2020 11:47 pm

.0035” skirt clearance. Calls for .0025”-.0045
Maybe you had fuel wash on initial start up..they do look scuffed which will pinch oil ring first.

Fuel in the oil too by the looks of the bearings.

How did it start up, quick with minimal cranking and fuel?
Fired right up. I didn’t do my normal break in though. Since it has a roller cam I didn’t run it 20 minutes at 2500 RPM. Then I had to break the gears it before I really put it through the paces. Baddies it in the beginning.
Oh well then, You seem have the answer for everything and every suggestion to why it shouldn’t have ate itself up.

Break in what gears and what’s a baddie?