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Discussion Starter #1 (Edited)
Alright everybody recently I found a source for the 4" Grade 8 flange bolts for the water pump. However there is a minimum quantity I have to purchase. So if anybody wants to upgrade their waterpump bolts from the stock grade 5 bolts (which the shaft is probably corroded on) I am putting together a kit of 4 4" bolts and 2 2" bolts for $13 shipped USPS Priority flat. Contact me either in this thread, through PM, or directly through email at [email protected] if interested.

Also please do not send payment unless I request it and give my payment email address. All sets of bolts from the current set of bolts are either claimed and waiting for payment or sold. I am keeping the GP open and when I have enough on the waiting list I will order another batch of bolts. - Peter
 

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Peter - What is the reason for Grade 8 bolts on a water pump?

I am not trying to be a PITA or diss your thread. I will be assembling my new engine VERY soon and am asking for a reason. If there is a compelling reason, I will buy a set of these bolts!

If I remember correctly, the bolt "grade" just determines tensile or breaking strength. We should never have to apply enough torque to exceed the breaking strength of a stock grade 5 bolt. I would assume that excessive tightening of a grade 8 bolt would crack/break the water pump housing if tightened too much.

I can see replacing the stock bolts with grade 8 bolts if you just want to replace them, but I don't know if it would gain you anything.

Is there any additional corrosion resistivity? I would assume that only stainless would do that.

Please let me know.

Thanks!
Tim
 

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I plan on removing my mechanical fan. Will this fix my problem of having 2 bolts that are too long?

Meaning: is the kit you offering for a car with a mechanical fan, or without it.
 

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Discussion Starter #6
Tim, The reason for the grade 8 bolt is grade 5 and lesser grade bolts stretch too much which can lead them to early failure. As we have all seen with the exhaust manifold bolts they break off easily especially #5 and #6 on the driver side(my personal car had #5 broke on the driver side and #6 on the passenger side had the head missing but shaft intact). Yes I know the water pump bolts are not in as high of stress application but still rust does develop on the threads and shaft of the bolt over time. I know looking at the bolts in my car I don't want to put them back into my car hence why I went looking for these bolts. In a quick search of the forum I found multiple people who have had the water pump bolts break on them.

Also in another application I have found that the grade 8 bolts are good replacements are in steering wheel pullers. Most bolts given with steering wheel pullers are actually less than grade five and I have had them stretch and break when pulling steering wheels and harmonic balancers so I replaced all my wheel puller bolts with grade 8 ones.

And Krazy40, Yes it will. I found some people just kept the bracket for the mechnical fan on but to me it looks cleaner and better to remove the fan bracket. The kit I am offering is for the dual electric fan setup. Also this does replace the stud on the driver side of the water pump with a bolt but the air pump bracket is still supported by other bolts as well.

I'm looking to at least get 5 takers now before I order so it won't be as much of a financial loss to me from having to order 50 bolts instead of just the 4 I need.
 

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Thanks Peter. Luckily, I have not had the corrosion issues on either of my cars, but I do see your point.

$13 is pretty easy to handle. I have bought so many $10-$100 items for this car that I stopped keeping track! :D I have an entire 6 foot wide 3 tier industrial shelf in my garage full of all of the parts I need to do my complete drivetrain swap! All I have left to buy is the transmission and then things will get interesting...

Please send me a PM with your PayPal info and I'll shoot you the $$$. May as well have these in hand when I start the engine assembly.

Thanks again,
Tim
 

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I had one long water pump bolt break.. Its a rare failure but if you reused the bolts many times perhaps one may stretch. If you run the air pump still you cant use two bolts for the 2 inch bolts. You need to reuse the factory stud

I have a thread on this matter from months ago and Purchased flange head black oxide grade 8 bolts in the store for the same price. I just bought them because I could get 6 for the price of one GM grade 5 bolt. I believe I was the only one who had one break as my block threads were poor.. You can get stainless bolts in this size as well. Once the Black oxide finish wears away, A grade 5 bolt will rust as quickly as a grade 8. Your More likely to break a Water pump bolt if the threads are dirty in the block (Which they were in my case, Packed with Rust and old sealant)
 

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Discussion Starter #10
I have a thread on this matter from months ago and Purchased flange head black oxide grade 8 bolts in the store for the same price. I just bought them because I could get 6 for the price of one GM grade 5 bolt. I believe I was the only one who had one break as my block threads were poor.. You can get stainless bolts in this size as well. Once the Black oxide finish wears away, A grade 5 bolt will rust was quickly as a grade 8. Your More likely to break a Water pump bolt if the threads are dirty in the block (Which they were in my case, Packed with Rust and old sealant)
That is true the bolt will still form rust, however grade 8 being a stronger metal than grade 5 steel is less likely to break. Thats why I am replacing any grade 5 bolts I come across with grade 8 bolts on the engine and any bolts in the exhaust system with stainless steel(ARP SS header bolts and stainless steel bolts for the cat converter to manifold bolts and the cat converter to exhaust system bolts). Also do note that standard stainless steel bolts you get at the hardware store are the equivalent to between grade 3 and grade 5 as far as strength of the bolt but offer superior corrosion resistance. As for specialty fasteners like the ARP's "Stainless 300" bolts they use a "proprietary" formula for their stainless steel that is stronger than grade 8 but much more expensive.

As for rust in the bolt holes. Clean it out using a 3/8"-16 tap(or appropriate size for the bolt hole(s) you need to clean out) and worry not about rust or other debris in the bolt holes, which will help ensure strong joints, good threads in the holes, and accurate torque readings. - Peter
 

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That is true the bolt will still form rust, however grade 8 being a stronger metal than grade 5 steel is less likely to break. Thats why I am replacing any grade 5 bolts I come across with grade 8 bolts on the engine and any bolts in the exhaust system with stainless steel(ARP SS header bolts and stainless steel bolts for the cat converter to manifold bolts and the cat converter to exhaust system bolts). Also do note that standard stainless steel bolts you get at the hardware store are the equivalent to between grade 3 and grade 5 as far as strength of the bolt but offer superior corrosion resistance. As for specialty fasteners like the ARP's "Stainless 300" bolts they use a "proprietary" formula for their stainless steel that is stronger than grade 8 but much more expensive.

As for rust in the bolt holes. Clean it out using a 3/8"-16 tap(or appropriate size for the bolt hole(s) you need to clean out) and worry not about rust or other debris in the bolt holes, which will help ensure strong joints, good threads in the holes, and accurate torque readings. - Peter
I know how to clean threads. I just used a brush and knocked out all the old sealant from the holes. It works just as good and cleaned up the threads fine. They were not damaged, Just dirty. Taps can widen the threads so I prefer not to use them if the threads are not damaged. I like the factory bolts over New bolts because all new hardware, whatever grade it is is made oversea's. :(
 

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put me down for two sets
 

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Discussion Starter #14
Alright as of Saturday May 29th around 8:50P Chicago time I have 2 maybe 3 sets of bolts not reserved yet. At this time I am only doing 12 sets of bolts due to having to purchase the bolts in sets of 50. Any over 12 I will start a waiting list for so when I get enough I will be able to fill those then. - Peter
 

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Discussion Starter #16
I will send out payment information on Tuesday June 1st. I will also be ordering the bolts then. - Peter
 

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Put me down for one set
 
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