Valve cover grommets Q

[icey756]

So you think i would be better off just getting hex bolts, washers, and rubber grommets? I was thinking about doing that if the felpro ones i was looking at was just the rubber piece. I did already buy 6 of the 12 bolts i need from a hardware store locally and i was going to go back and get 6 more when they were in stock. Also I dont have a torque wrench. I plan on getting one next week but the think is the one im looking at is 20-150 foot pounds. So the lowest i could get in inch pounds is 240. I really dont have the money 2 of them and besides that, the lowest one they have only goes down to 20 inch pounds

[cre]

12 in lbs is equal to 1 ft lb (seems obvious but many people miss it). Just a hand tightened screw will meet this level without exceeding it by much; I suspect this is a strong reason for Toyota's decision to employ Philips screws on many of their vehicles for this purpose. If you're set on switching to bolts and don't have a suitable torque wrench for the job then I recommend you tighten them by hand using a long extension as you would a screw driver.

If you can find some resiliant rubber washers then sure, your own combination will work fine. If you're using something other than rubber such as fiberglass washers you don't need to use metal washers if the bolt has a flanged head (kind of like a washer cast into it for greater contact area). Don't use a flanged head bolt with a rubber washer without something in between to prevent the washer from "winding up".

The best (albeit overkill) setup would be a constant tension setup. Like the OEM hose clamps it's a setup that allows for the expansion, contraction and movement of the materials it binds. This would use a longer bolt and two washers sandwiching a spring. You'd want a spring which is compressed around 50% to 75% when the fastener is torqued to the desired level.

In all cases lubricating the parts prior to torquing for accuracy isn't a bad idea. I'd just use graphite... maybe moly on a constant tension setup.



EDIT: I'm not sure if there are any economic low range torque wrenches on the market. Mine is Snap-On and cost a crap load more than would be worth it to most people. As the wrench's length is a function of the torque it wouldn't be difficult to make an attachment to function as a divider..... then again, maybe you should just see if someone will rent you one.

I see in your sig that you say you have ARP headbolts at 90ft lbs.... I hope that's a typo and you mean headSTUDS.... you don't want to exceed 75ft lbs on ARP or OEM headBOLTS (unless you lubed them with something less lubricating than the molybdenum grease they originally ship with).

[cre]

Originally Posted by icey756

Also I dont have a torque wrench. I plan on getting one next week but the think is the one im looking at is 20-150 foot pounds. So the lowest i could get in inch pounds is 240. I really dont have the money 2 of them and besides that, the lowest one they have only goes down to 20 inch pounds

When selecting a torque wrench for a given job you are best choosing one where the desired torque falls within the middle 50-60% of the wrench's scale for the best accuracy. Leave a 20 to 25% margin on the top and bottom as most types of wrenches are not terribly accurate at the end of their scope. A beam type is easily one of the most consistent and accurate and calibration is a one second affair. Whatever type you get make sure to always zero it out (or set to whatever the lowest setting is) before storing. Periodic testing and calibration is recommended for anything other than a beam type wrench (You can use a beam type to test the others yourself. ).

You can extend the range of a torque wrench with a multiplier. This is an extension of sorts for the torque wrench. The basics of it are if you add an extension which doubles the length of the wrench it doubles the wrench's capacity (so you then double the reading on the scale.... for 20ft lbs you'd only aim for 10ft lbs).

[icey756]

Well i think its overdue that i get my own torque wrench anyway so I'll do some more research. When I got the studs thats what they said to torque to i think. Maybe it is a typo but i would have to double check. Pretty sure i made 3 passes of 30, 60 and then 90

[cre]

Originally Posted by icey756

When I got the studs thats what they said to torque to i think. Maybe it is a typo but i would have to double check. Pretty sure i made 3 passes of 30, 60 and then 90

We've covered this. There IS a difference depending on whether you installed studs or bolts just as the type of lube makes a difference. If you installed studs and used the supplied moly grease then you've done well and need not worry... Bolts on the other hand you would only torque to 90 if you used motor oil in lieu of a good moly lube. Follow?

[icey756]

yes i follow. And sorry i mean i have bolts not studs. We just used the stuff they gave us and torqued them to 90. No oil involved. Why is that a big deal?

[cre]

Google fasteners and yield strength. The head isn't designed for that level of torque (hell, your rims aren't and they have a beefier cross section) and the fasteners are designed to remain within a certain margin to maintain a specific level of elasticity.... Who told you to just "go ahead"? If it was in a thread on here let me know so I can remove it. If Toyota designed for using torque to yield fasteners (aka TTY) you'd be in real deep shit.


EDIT: On second thought don't Google it, you'll find all the bad info first. Go buy some mechanical engineering texts and start studying.... or read the directions next time (they're not included because the manufacturer is bored).

I posted a little more on this here: http://www.toyota-supra.info/forums/...ad-gasket.html ...and a lot more on the subject in the past.

[icey756]

what do u suggest i do then? Loosen them or what?