which main and rod bearing to check first?

pmrphil · 02-06-2016, 10:26 PM

Normally I'll look at #2 and #4 mains, as any crank flex usually shows up there first.

Dave Gantz · 02-07-2016, 10:37 AM

I have a 350 in a work truck with a knock. A friend who owns a repair shop told me to pull the ones farthest from the oil pump first.
I haven't been able to do it yet. I had shoulder surgery in the fall and can't work over head. Something tells me a new short block is in my future...

V M Kauffman · 02-07-2016, 12:32 PM

2 and 4 on mains due to crank bending on rods I was taught to do the first pair of rods that get oil from pump. Reason if pump sucks air (runs out of oil) it will show up there rod journal 1 & 5 on a small block Ford.

Quote:

Originally Posted by Dave Gantz

I have a 350 in a work truck with a knock. A friend who owns a repair shop told me to pull the ones farthest from the oil pump first.
I haven't been able to do it yet. I had shoulder surgery in the fall and can't work over head. Something tells me a new short block is in my future...

Tom Goldman · 02-07-2016, 01:37 PM

Quote:

Originally Posted by pmrphil

Normally I'll look at #2 and #4 mains, as any crank flex usually shows up there first.

Always #2 & #4 on the mains ,even if the rods look good ,which they sometimes do, those two mains are the precursors to doom !

MAURICE BLENDHEIM · 02-07-2016, 06:03 PM

If the pan is off. Why not check all of them for the time it takes? That way you won't be wondering. MB.

Dyno · 02-07-2016, 09:23 PM

I used to buy 454 core Chev engines. If 5 & 6 rod bearings were good, the rest were good. If they were bad, you usually would find a burned main bearing.

Mike Taylor 3601 · 02-08-2016, 09:50 AM

Quote:

Originally Posted by MAURICE BLENDHEIM

If the pan is off. Why not check all of them for the time it takes? That way you won't be wondering. MB.

The ones you don't check will be where a problem is.

jims5600,
If have thrust trouble may want to increase converter/pump clearance, that is one thing that is best to have at maximum clearance.I have always been told from 1/8 to 3/16,bottom converter in pump and come back out 3/16''. If doesn't have enough clearance when on the brake and converter balloons and puts more pressure against thrust. if auto is wearing thrust it is most likely that converter needs more clearance between it and the pump.
Mike Taylor 3601

02-06-2016, 10:26 PM	#1
pmrphil Member Join Date: Aug 2010 Location: CT Posts: 464 Likes: 1,844 Liked 348 Times in 152 Posts	Re: which main and rod bearing to check first? Normally I'll look at #2 and #4 mains, as any crank flex usually shows up there first. __________________ Phil Molski PMR Performance S/C 1623

02-07-2016, 06:03 PM	#5
MAURICE BLENDHEIM Senior Member Join Date: Jun 2011 Location: Langley (no igloos), British Columbia, Canada Posts: 569 Likes: 311 Liked 285 Times in 87 Posts	Re: which main and rod bearing to check first? If the pan is off. Why not check all of them for the time it takes? That way you won't be wondering. MB.

02-07-2016, 09:23 PM	#6
Dyno Senior Member Join Date: Dec 2002 Posts: 920 Likes: 1,149 Liked 695 Times in 206 Posts	Re: which main and rod bearing to check first? I used to buy 454 core Chev engines. If 5 & 6 rod bearings were good, the rest were good. If they were bad, you usually would find a burned main bearing. Last edited by Dyno; 02-08-2016 at 03:15 PM.

02-07-2016, 10:37 AM	#2
Dave Gantz Senior Member Join Date: Nov 2005 Location: Verrry South Jersey Posts: 537 Likes: 134 Liked 251 Times in 125 Posts	Re: which main and rod bearing to check first? I have a 350 in a work truck with a knock. A friend who owns a repair shop told me to pull the ones farthest from the oil pump first. I haven't been able to do it yet. I had shoulder surgery in the fall and can't work over head. Something tells me a new short block is in my future...