More Haynes manuer!, says get slack out of T belt by putting 18 ft-lbs torque CCW on Cam sprocket bolt = impossible!

[Craigar]

These camshaft sprocket bolts only get 7ft-lbs torque! how can you "un-torque or torque it counterclockwise "  to 18 ft-lbs? it will unscrew! It's in section 34 from page 2B-6 - Haynes manual 89003

 

Subaru FSM says use a "belt tension wrench" that spans the sprocket (I assume?) & torque on it to 18 ft-lbs counter clockwise, then tighten tensioner..

 

so how do you guys get the tension right?

Thanks

again

Edited November 5, 2018 by Craigar

[idosubaru]

1. Throw away the Haynes manual. 

2. It’s not 18 pounds at the cam bolts as you’re assuming. It’s 18 pounds from the center, but the cam bolts are off center and therefore the torque value at the cam bolts would be less than the torque value at the center line where 18 pounds is intended. 

What is the value?  Measure, study some leverage calculations and do the simple math, or just ignore it, it doesn’t matter.  You just need to get the slack out of it. 

3. Just try to put a few pounds on it and do your best.  Not a big deal. I’ve probably done 100-200 timing belts and don’t need a torque wrench. 

[DaveT]

I made a wrench from a thick piece of aluminum and a couple of bolts.  Square hole in the center for my torque wrench years ago.  I use the fsm numbers.   Once they are on, run it for 20 seconds or so.  Re check the setting, as they often drift into place where they want to run, and the tension changes.

Watch ebay for a used fsm.

[Craigar]

I agree with everything you guys said - including throwing away the Haynes manual - AND FOUND ANOTHER ERROR (wrong distributor firing order) , but that will be a new topic..and I actually (embarrassingly misplaced) have a printed FSM manual set I bought off fleabay about 2 years ago - I am so grateful we have the old online FSM manual for this car (nad Ej22 &EJ25) at http://jdfinley.com/file-downloads/subaru-manuals/  , I downloaded the .pdf and can flog myself with them at my leisure, even view them in my cellphone

I *think* Subaru is probably trying to reproduce the spring tension of the valve springs pushing against the cam at the point of highest spring pressure (for either cylinder 1&2 passenger side, or 3&4 driver driver side at) if examining passenger side cylinders, it would happen at the instance that the intake stroke of valve of cylinder 1 is lifting, while the exhaust stroke valve of cylinder 2  is lifting - and about the same time cylinder 3 will be starting it's power stroke.

So *if I thought this out right* now that I already have the belts on in the proper position cam timing wise I can rotate the crankshaft pulley bolt with a socket (clockwise to get tension on correct side of belt, opposite of the side with the tensioner) and feel this resistance (of course got to pull the spark plugs so the compression doesn't get involved.. and take cap off rotor to roughly calculate where the valves are)and I really don't want to pull them or the cap, cause I'm so lazy ) and it should even show on a "deflection" torque wrench.... I may even be able to show a "reproducible" deflection of the belt itself using a musician's tool for determining tension on a drum head/skin - or a banjo (which is my current obsession) it's called a "drumdial" it's just a dial gauge (with a heavier spring on the plunger) mounted through a hole in the center of a 2" circular base that has a flat bottom. 

-=- I want you guys to know this is more focused thinking that I have done since I can remember -=-

so I'm gonna go and try it and maybe even shoot one of my infamous "technical vids.." if it shows on the torque wrench - then I'll hold it there & tighten the tensioner bolts.

I'm sure Abraham Lincoln got much more profit and satisfaction out of splitting logs, than I will ever get out of ending up looking like I'm working on "splitting hairs"..

 

Edited November 5, 2018 by Craigar
typos & brainos

[jono]

I made a timing belt tension tool by using spare cam wheel adding four M6 x 20 bolts through from back of each the four holes secured with a nut so bolts extend beyond nut

Then make tool as it is now kiss face to face with cam wheel align bolts into matching holes then a ccw torque wrench ( better known as wrist)

Oh yeah, a short M10 bolt and nut through centre hole to run 'torque wrench' on centrally

Edited November 5, 2018 by jono
sessual pleasure

[Craigar]

Ya all will never guess what THIS is ??

My local "independent Subaru Repair" guy, Chris Raffi LENT IT TO ME!  What a nice guy and he keeps up a nice looking shop too, so if anyone is close to 90260 and they need pro service give him a call 310-674-5226 Raffi Motors. I'll also still see if my "DrumDial" shows differences in deflection. Now the only problem I have is I only have 3/8" torque wrenches - why they used a 1/2" female for just 25 ft/lbs. max is serious overkill IMHO.

[Craigar]

well I tested the belts "deflection"  with the drum dial and it really responded to the tension on the belt that remained after the tensioner is locked down - my "guesstimate"  by pushing pretty hard with my hand on the tensioner before I tightened showed 78 on the drum dial , without tensioning the belt and only letting the spring in the tensoiner apply the force , it showed 75 - measuring after following the FSM manual it was at 81(all on the passenger belt)

 

here's the tool (red plate on the left) with the torque wrench on it - the torque wrench on the right is for the tensioner bolt.

if the drum dial is sitting on a flat surface like a mirror, it should be at zero, here it is on a mirror

 

Edited November 7, 2018 by Craigar