SBC Oil Pump Bolt Torque

Dave Gantz · 03-11-2016, 11:39 AM

7/16-14
Several online sources say 65# for a SBC oil pump bolt. A bolt torque chart says 70# dry and 55# oiled, for a grade 8 bolt, which it is. (6 radial lines)
The bolt started crushing the oil pump before the wrench clicked. It's the same pump I took off.
I yam con-fused.
It's a 94-ish 350 crate motor in a work van.

richie 2 · 03-11-2016, 11:58 AM

#50 oiled is my number. check yer wrench...

Ed Wright · 03-11-2016, 09:19 PM

You should also have the part of an oil pump bolted to the rear main cap when you have it align honed. The better shops I have been to all do that. Same torque on the bolt when installing the pump. I always used 50lbs, lubed.

Adger Smith · 03-11-2016, 10:40 PM

Ed is spot on.
The rear main will go out of round just like using or not using a TQ plate on the deck for the cylinders. I always align hone with 55 & oil on a bolt, a stud @ 50 with moly lube when I align hone and assy. I use my same assembly TQ wrench on it, too It is critical. Why even bother align honing if you are going to pull it out of round when you put it together??

Ed Wright · 03-11-2016, 11:47 PM

I always use a stud for the pump. Should have included that.

Dave Gantz · 03-12-2016, 10:25 AM

I will check the wrench. It's a Snap On, I guess I could give it to the local Snap On guy for calibration. It's never given me any issues, and I had just torqued the rods previous to "torquing" the pump. But, anything can happen.
I'll try 50# oiled, when I get the new pump.
Thanks for the advice on the align honing. It's in a work van.

richie 2 · 03-13-2016, 07:03 PM

I cant imagine crushing the pump housing...where did that pump come from?

Dave Gantz · 03-14-2016, 08:54 PM

Quote:

Originally Posted by richie 2

I cant imagine crushing the pump housing...where did that pump come from?

It was on the engine when I got it. I could feel it giving as I pulled on the wrench. It didn't feel as if the bolt was breaking; it just kinda kept going. Hard to explain. The area that crushed is right under the bolt head. It's why I kind of figure the wrench is okay. It feels the same tightening other bolts as it aways has. -Certainly not a calibration test.
I haven't looked at it closely yet. I'm working under the truck and was more than ready to quit when I felt that!

I have the new one. I'll try posting pictures of each.

richie 2 · 03-16-2016, 04:58 PM

sneak up on the #50. let it sit for 15 minutes before heading to the final number. Im hearing horror storys on the redesigned & fragile sbc M55 pump housings from mellings....

BillK · 03-16-2016, 10:46 PM

Dave,
Probably too late now but the factory spec is 65 lb ft. The bolt is almost identical to a short head bolt so it makes sense that the torque would be close.

Bolt charts are ok for "generic" fasteners but most engine fasteners are designed for a specific use and the factory torque specs should be used if available.

I have probably done a hundred of them and never have had the issue you mentioned with the bolt crushing the pump. I really think it would be a good idea to get your torque wrench checked or at least compare it to another one. If it is one of the Snap On wrenches with the little knob on the side I have had two of them start sticking and not releasing properly. One was a 3/8 and the other a 1/2" drive. I have replace both of them with "traditional" Snap On wrenches, I just could not trust them

Just my opinon,

03-11-2016, 11:39 AM	#1
Dave Gantz Senior Member Join Date: Nov 2005 Location: Verrry South Jersey Posts: 537 Likes: 134 Liked 251 Times in 125 Posts	SBC Oil Pump Bolt Torque 7/16-14 Several online sources say 65# for a SBC oil pump bolt. A bolt torque chart says 70# dry and 55# oiled, for a grade 8 bolt, which it is. (6 radial lines) The bolt started crushing the oil pump before the wrench clicked. It's the same pump I took off. I yam con-fused. It's a 94-ish 350 crate motor in a work van.

03-11-2016, 11:58 AM	#2
richie 2 Senior Member Join Date: Feb 2009 Posts: 971 Likes: 426 Liked 205 Times in 93 Posts	Re: SBC Oil Pump Bolt Torque #50 oiled is my number. check yer wrench...

03-11-2016, 09:19 PM	#3
Ed Wright Veteran Member Join Date: Mar 2005 Location: Sand Springs, OK Posts: 8,132 Likes: 896 Liked 390 Times in 170 Posts	Re: SBC Oil Pump Bolt Torque You should also have the part of an oil pump bolted to the rear main cap when you have it align honed. The better shops I have been to all do that. Same torque on the bolt when installing the pump. I always used 50lbs, lubed. __________________ Ed Wright 4156 SS/JA

03-11-2016, 10:40 PM	#4
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,446 Likes: 575 Liked 880 Times in 311 Posts	Re: SBC Oil Pump Bolt Torque Ed is spot on. The rear main will go out of round just like using or not using a TQ plate on the deck for the cylinders. I always align hone with 55 & oil on a bolt, a stud @ 50 with moly lube when I align hone and assy. I use my same assembly TQ wrench on it, too It is critical. Why even bother align honing if you are going to pull it out of round when you put it together?? __________________ Adger Smith (Former SS)

03-12-2016, 10:25 AM	#6
Dave Gantz Senior Member Join Date: Nov 2005 Location: Verrry South Jersey Posts: 537 Likes: 134 Liked 251 Times in 125 Posts	Re: SBC Oil Pump Bolt Torque I will check the wrench. It's a Snap On, I guess I could give it to the local Snap On guy for calibration. It's never given me any issues, and I had just torqued the rods previous to "torquing" the pump. But, anything can happen. I'll try 50# oiled, when I get the new pump. Thanks for the advice on the align honing. It's in a work van.

03-11-2016, 11:47 PM	#5
Ed Wright Veteran Member Join Date: Mar 2005 Location: Sand Springs, OK Posts: 8,132 Likes: 896 Liked 390 Times in 170 Posts	Re: SBC Oil Pump Bolt Torque I always use a stud for the pump. Should have included that. __________________ Ed Wright 4156 SS/JA

03-13-2016, 07:03 PM	#7
richie 2 Senior Member Join Date: Feb 2009 Posts: 971 Likes: 426 Liked 205 Times in 93 Posts	Re: SBC Oil Pump Bolt Torque I cant imagine crushing the pump housing...where did that pump come from?

03-16-2016, 04:58 PM	#9
richie 2 Senior Member Join Date: Feb 2009 Posts: 971 Likes: 426 Liked 205 Times in 93 Posts	Re: SBC Oil Pump Bolt Torque sneak up on the #50. let it sit for 15 minutes before heading to the final number. Im hearing horror storys on the redesigned & fragile sbc M55 pump housings from mellings.... Last edited by richie 2; 03-16-2016 at 05:01 PM.

03-16-2016, 10:46 PM	#10
BillK Member Join Date: Nov 2005 Location: Waldorf Md Posts: 230 Likes: 12 Liked 30 Times in 17 Posts	Re: SBC Oil Pump Bolt Torque Dave, Probably too late now but the factory spec is 65 lb ft. The bolt is almost identical to a short head bolt so it makes sense that the torque would be close. Bolt charts are ok for "generic" fasteners but most engine fasteners are designed for a specific use and the factory torque specs should be used if available. I have probably done a hundred of them and never have had the issue you mentioned with the bolt crushing the pump. I really think it would be a good idea to get your torque wrench checked or at least compare it to another one. If it is one of the Snap On wrenches with the little knob on the side I have had two of them start sticking and not releasing properly. One was a 3/8 and the other a 1/2" drive. I have replace both of them with "traditional" Snap On wrenches, I just could not trust them Just my opinon, __________________ Bill Koustenis

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