Will ARP 120-2501 balancer bolt work as a replacement for 2005 Buick Century?

[Reg Sackmann]

I replaced 3 crank position sensors over the past 20 years or so on 3 different 3800 powered cars. I have never had any issues with re-using the crank pulley bolt.

I've seen a few poeple who have said the same thing. Might have to give it a shot and cross my fingers.

 

[Reg Sackmann]

You could see whats' available on ebay or else match it up at mcmaster-carr (McMaster-Carr).

Not finding anything on McMaster-Carr, but it's a cool site, thanks for sending.

 

[StealthESW]

Not finding anything on McMaster-Carr, but it's a cool site, thanks for sending.

This part number is the most recent replacement part number due to it being the most recent production hardware. So, the Old part number 14102659 was replaced with 11570965. So, technically it is the same part.....and covers 1987-2005 GM 60 degree V6s 2.8L, 3.1L and 3.4L.

Your other option is to look for a hardened bolt at the hardware store that is M12x1.5 and 45mm long from the base of the flanged head. I would not take this option as long as the bolt at the link I listed is available. That bolt will work. It is the same bolt as the newest part number for it. Part numbers change in systems when there is a revision or a change in manufacturer. Having a part number change but be the same part is not uncommon with Automotive parts.

 

[Reg Sackmann]

Hmmm, food for thought. I'm assuming I can't order this part directly from Mike Maroone South Chevrolet? I see no actual purchase option there. I've reached out to them. Thanks again for the insight.

 

[Reg Sackmann]

Response from Mike Maroone South Chevrolet: part is no longer available and therefore not for sale.

 

[StealthESW]

You could pull a bolt from a salvage engine and use it to compare to ARP Bolts Kits. Don't focus on if it says it will fit. You just need it match the specks of the bolt you take out. ARP may not be torque-to-yield and they could be re-useable, so the 30 or so bucks could very well be worth the investment. The bolt needs to match in length with the washer installed and the threads need to match. The ARP bolts are properly hardened, so no need to worry about that. I don't carry ARP or would check this myself for you. Contacting ARP customer service at 1-800-826-3045 could be an option.

 

[StealthESW]

I think a grade 10.9 M12 x 1.5 thread bolt would work if you can find it in or cut it the correct length.

 

[StealthESW]

My understanding after some deep digging is that the original bolt on the 2005 Century is not Torque-to-Yield (TTY). I am just seeing 10.9 class fasteners were used. If this is the case, then you should be able to re-use your old bolt with some medium blue locktite after a through clean of the bolt and bolt hole. Torque should be 80 ft-lbs. Cylinder head bolts are all I show that are TTY that I see.

 

[ulycyc]

The bolt is TTY. Here are the buick century specs.

Fastener Tightening Specifications — 2005 Buick Century V6-3.1L VIN J Service Manual ~ LEMON Manuals

Repair manual for the 2005 Buick Century V6-3.1L VIN J, including electrical diagrams, bolt torques, and labor times.

lemon-manuals.la

 

[chem_man]

Here is a link to a Grade 10.9 M12x1.5x45 bolt -

M12X1.5 OEM Hex Flange Bolt - Steel 10.9 Zinc Flake

Bel-Metric sells metric hardware & specialty automotive supplies worldwide. Visit our website to purchase metric fasteners, nuts, bolts, screws, washers & more.

belmetric.com

While it is not TTY, it should be strong enough for your application.

Or, you can order ARP M12x1.5x45 bolts from Summit Racing - https://www.summitracing.com/parts/arp-664-1005?seid=srese1

 

[StealthESW]

Here is a link to a Grade 10.9 M12x1.5x45 bolt -

M12X1.5 OEM Hex Flange Bolt - Steel 10.9 Zinc Flake

Bel-Metric sells metric hardware & specialty automotive supplies worldwide. Visit our website to purchase metric fasteners, nuts, bolts, screws, washers & more.

belmetric.com

While it is not TTY, it should be strong enough for your application.

Or, you can order ARP M12x1.5x45 bolts from Summit Racing - https://www.summitracing.com/parts/arp-664-1005?seid=srese1

I think this is the best alternative. I have heard very little negative stuff about ARP, and there is a decent chance the replacement will not be TTY. A re-useable replacement would be ideal in either case. I don't do wrench work professionally anymore except for myself these days. I do deal in obsolete auto parts though.

I do know that at the dealership near by, they reuse those bolts for what it is worth. I also know I have reused them too at our shop with no issue, not to say that it can't happen. All things are possible. However, if a ARP replacement can be found, then that is great. The 3.1L was a very heavily used engine across GMs lineup for several decades, the possibility of there not being a single option makes very little sense. I know that engine was used through and may have been phased out just after the 2005 model year, which I think was the last year before it was replaced by the 3.4L. I think, it's been a minute. All that said, there were millions of those engines and it's variants floating around world wide.

If Dorman does not have one, then making a plea to ARP to produce one specifically for the 3.1L with torque specs should be considered and may take the community to back a representative or just flood their inbox.

 

[chem_man]

I think this is the best alternative. I have heard very little negative stuff about ARP, and there is a decent chance the replacement will not be TTY. A re-useable replacement would be ideal in either case. I don't do wrench work professionally anymore except for myself these days. I do deal in obsolete auto parts though.

I do know that at the dealership near by, they reuse those bolts for what it is worth. I also know I have reused them too at our shop with no issue, not to say that it can't happen. All things are possible. However, if a ARP replacement can be found, then that is great. The 3.1L was a very heavily used engine across GMs lineup for several decades, the possibility of there not being a single option makes very little sense. I know that engine was used through and may have been phased out just after the 2005 model year, which I think was the last year before it was replaced by the 3.4L. I think, it's been a minute. All that said, there were millions of those engines and it's variants floating around world wide.

If Dorman does not have one, then making a plea to ARP to produce one specifically for the 3.1L with torque specs should be considered and may take the community to back a representative or just flood their inbox.

You missed the part about the ARP bolts:

Or, you can order ARP M12x1.5x45 bolts from Summit Racing - https://www.summitracing.com/parts/arp-664-1005?seid=srese1

 

[HotZ28]

I don't understand all the hysteria from the OP about one frigging bolt in two different threads here! He has got good advice before, just use the old bolt!

 

[Reg Sackmann]

I don't understand all the hysteria from the OP about one frigging bolt in two different threads here! He has got good advice before, just use the old bolt!

Yes, two separate threads because I hadn't gotten responses until recently - for which I'm thankful, BTW.
Re-using the existing bolt is certainly a possibility, one which I'm not ruling out but it's not a slam-dunk to go that route as there is plenty of opinion out there to NOT do that.
I am heartened, however, in the number of people who have re-used the bolt seemingly without issue but I'm also hedging my bets by ordering ARP bolts just in case. The real issue is that the manufacturer has stopped making the bolt itself, with every balancer out there ships without the bolt - which just seems asinine.

 

[StealthESW]

You missed the part about the ARP bolts:

Or, you can order ARP M12x1.5x45 bolts from Summit Racing - https://www.summitracing.com/parts/arp-664-1005?seid=srese1

I didn't miss that part. The first line was me agreeing with you on the ARP bolt. ARP has a bolt that is for a Harmonic Balancer on a Ford that matches the specs exactly of the one for a 3.1L, btw.