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Scared to loosen 18 year old thermostat bolts!

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Re: Scared to loosen 18 year old thermostat bolts!

Post by 98V70T5 » Fri Dec 09, 2016 10:52 am

I can't say my memory serves me well on the size. I have a full set of Torx bits, so it may be a T-40, I just typed the wrong size. Just for the record.

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Re: Scared to loosen 18 year old thermostat bolts!

Post by osmium » Fri Dec 09, 2016 11:07 am

98V70T5 wrote:I can't say my memory serves me well on the size. I have a full set of Torx bits, so it may be a T-40, I just typed the wrong size. Just for the record.
Did this job earlier in the year, but had the same concern about the bolts.

I PB blasted the bolts everyday for about a week.

Bought the correct size Torx bit from Home Depot (Husky?) Had no problem getting the bolts loose after giving them a few taps.

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Re: Scared to loosen 18 year old thermostat bolts!

Post by sleddriver » Fri Dec 09, 2016 11:51 am

My soln was to buy a long-shaft Torx screwdriver with a flat on the handle. Even then I bent the male driver end! Used AL anti-sieze upon reinstallation. No worries since.
1998 V70 T5 226,808 miles. Original Owner.
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Re: Scared to loosen 18 year old thermostat bolts!

Post by 98V70T5 » Fri Dec 09, 2016 1:33 pm

sleddriver wrote:My soln was to buy a long-shaft Torx screwdriver with a flat on the handle. Even then I bent the male driver end! Used AL anti-sieze upon reinstallation. No worries since.
How did you get leverage using a screwdriver?

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Re: Scared to loosen 18 year old thermostat bolts!

Post by abscate » Fri Dec 09, 2016 1:39 pm

Clean out the bolt head with a dental pick - really dig all the stuff out.

PB blaster or your favorite brew applied every day for a week before, then put the bit into the head and give it light taps with a hammer to work the solvent into the the heads

Go out and buy a brand new Torx bit, a good quality one (not HF) and even think about ordering a SnapOn if a stripped head will be a real problem.

Get the bit absolutely straight in and up/down before applying torque.
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Re: Scared to loosen 18 year old thermostat bolts!

Post by BEJinFbk » Fri Dec 09, 2016 2:20 pm

+1 for Liberal and Long Term application of PB Blaster and getcha one of these:
image.jpeg
Don't cheap out at Harbor Freight... Get a GOOD one!
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Re: Scared to loosen 18 year old thermostat bolts!

Post by erikv11 » Fri Dec 09, 2016 4:44 pm

98V70T5 wrote:
sleddriver wrote:My soln was to buy a long-shaft Torx screwdriver with a flat on the handle. Even then I bent the male driver end! Used AL anti-sieze upon reinstallation. No worries since.
How did you get leverage using a screwdriver?
With palm-heel of left hand, push the screwdriver straight down. Hard.
With right hand, use channel locks on the handle to rotate the screwdriver.

My "long torx" for this application is actually a T40 screwdriver, that's exactly how I do it when a new (old) P80 comes into the fleet. Pliers will mar the screwdriver handle a little but that's OK. Second time around they are easy to turn, I just use the screwdriver by had. If I haven't swapped in cam cover bolts already.
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Re: Scared to loosen 18 year old thermostat bolts!

Post by 98V70T5 » Fri Dec 09, 2016 6:13 pm

Wow, that's a way of loosening them (screwdriver+channel locks), that I would have never considered. Is there an advantage in using the screwdriver vs. just using a ratchet and Torx bit?

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Re: Scared to loosen 18 year old thermostat bolts!

Post by cn90 » Fri Dec 09, 2016 8:09 pm

When dealing with stubborn bolt, there are 2 different problems:

1. Broken in half: since the tstat bolt has a Torx head (and not a hex head), this is not going to happen b/c the Torx head will strip first as it does not have good bite like a normal hex head.

2. Stripped head, no worry, just drill it out.
Lowes Hardware sells good drill bits made by Bosch (made in Germany).
Robert DIY posted this video a while back:






Get 2 spare bolts ahead of time either from dealer or local hardware store.
Home Depot has these bolts: 7mmx1.0mmx30mm.

During installation, apply some anti-seize.
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Re: Scared to loosen 18 year old thermostat bolts!

Post by rspi » Sat Dec 10, 2016 4:53 am

Please don't hit it with force. Changing the housing is no fun.

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