I just did my T-belt and seals, but I'm leaving the covers off because I'm a little woozy over something and figured I'd search/post a question.

My Accord has 191k and this is the second t-belt, the springs on the tensioners are originals.

Well here's my issue, all the other t-belts I've ever done with automatic tensioners, once you release them, the belt is very taught...however, on my honda, the timing belt is a little snug but still kinda loose. And the balance shaft belt WAY loose. I've got springs pulling the tensioners...but...I'm not convinced they are automatic ones...are they?


The 10mm bolt that goes in the block that locks the t-belt tensioner in it's tightness was missing when I took my covers off. The spring is pretty good though (still kinda tough to pull, I used pliers to place it).

On the balance shaft tensioner...I bolted everything up and was able to put the spring on with no effort at all...the balance shaft belt is VERY loose. But the spring is in decent shape...it's almost fully compressed and doesn't pull.

So here are the questions...do I have to leave the tensioners at the mercy of the springs (assuming they are reversed I guess I could swap them back and they would be kept tight)? Why not just make the belts tight and then tighten my 10mm bolts and not rely on the springs at all?

Of course as the belt ages it could get slack...and since these springs don't seem to be tight..my belt won't stay tight right?

Also...according to haynes and a fsm I downloaded, you can adjust the belt tension by adjusting the 14mm bolt that holds the tensioners on...just how does this bolt do that? All it does is keep the tensioners from coming off the bolt they slide onto...from what I see the tension is "adjusted" via the springs and held by either the springs or by retightening the 10mm bolts.


My manuals aren't very helpful at this point because neither shows how the 14mm bolt does any adjusting and I don't see how it could...nor do they tell me whether or not I should tighten (and to what torque spec) the 10mm bolt on the timing belt tensioner and the 10mm bolt on the balance shaft tensioner (it's actually inbetween the tensioner and the spring on a metal arm)

 

Few years have automatic tensioners. I think yours are like most; the spring is only working when you loosen the tensionerbolt. Then you tighten the bolt to lock the tensioner into position. That spring isn't strong enough to maintain tension while the engine is running.

If the tensioner bolt is missing, you better get one quick.

Finally, the belt isn't gonna be TIGHT like an alternator belt. You shouldtake the long span (exhaust side) & you should just barely be able totwist it 90 degrees in the middle.

 

THANKS for the reply JimBlake,
I believe what I was looking at is actually the place where a cover bolt goes...wierd design if you ask me.
There is a 14mm nut that keeps the tensioners in place, it also keeps them from moving/loosening.

The manuals I've read (and other how-to's) never specifically address the proper procedure for manually tightening the belts, the best I've seen was a guy on another forum said to turn the cam three teeth counter clockwise and then tighten the adjusting bolt...but again...this is going to rely on spring pressure to tighten the belt.

I will retry the steps in the how-to I found (www.honda-tech.com) some time later, but most likely I will have to tighten the belts by hand somehow.

thanks again though!

 

Take a look at what deserthonda has to say about that tensioner boltin this thread:
https://www.hondaaccordforum.com/m_47917/tm.htm

Also in that thread there's the Honda procedure for adjusting belt tension. While your covers are still off you might want to give that procedure a try so you'll see what's happening.

 

The tensioner nut is #26, it's actually ouside the lower timing cover. It locks down the 2 tensioner pulleys (#10 & #17). The pivot bolt is #23 and that one won't lock down the tensioners because it's a shoulder bolt.

Some people have used a coathanger to pull & help the tensioner springs beforethey tighten #26. Don't overdo it.



PS... To tighten things, the timing belt tensioner pullyneeds to move upwards & the balancer belt tensioner pulleyneeds to move downwards. Pay attantion to the arrangement of their levers & pivots.

 

I ended up going back over the steps I've found and tightening the t-belt just a bit (and I do mean just a LITTLE bit) more than that spring did by itself, about to where the other belts I've done on other cars were.

On the balancer shaft belts I realize it was not meant to be too tight. I tightened it enough to take out the slack really, but nothing excessive.

The car runs great, no noises, no problems. Runs like a champ still. Runs a little bit better but that's because my spark plugs and plug wires were old and worn not because of the belt change. Actually I think it's idles a bit more smoothly though...but I think that's just my imagination...I was pretty **** about lining up that balancer shaft housing (redid the o-ring on it) though.

I do recommend that anyone else in this position replace those springs, ESPECIALLY if this is t-belt in multiple of 2. This isn't my first rodeo so I had some exp. to draw on but not everyone does...so it's best to play it safe.

Another fella on a different forum noted that he had a similar issue with that spring, he went to the dealer and had them double check the part numbers, the spring was too long but showed up as the right part...odd

Thanks for all your replies!

 

I think the important thing for usDIY'rs to appreciate is that, unlike other smooth drive belts, these Honda timing and balance-shaft beltsdo their"work"at the sides of the teethof those pulleys. The side of eachtooth of the belt literally pushes against the side of the corresponding tooth in the pulley. Theyexert force through tension only andnot by anycoincidentalfriction force such as that occuring between the smoothexternal alternator and steering pump belts and the correspoinding smooth pulleys. (For example, in the latter, without friction the beltswoulddo no work. In the former, one could likely pour Mobil 1 on the belts and they'd still do their work -probably even better.)

The two tensioners serve only to minimizeexpansion of their belts' "circuit" (the shape and size of the path of the belts) due to the centrifugal force exerted during operation. Such a change would of course affect the ignition and balancer "timing".

In this regard it should alsobe notedspecifically wherethe belts do thier"work". In the case of the timing belt, the work occurs in thevertical path between the 9 o'clock position on the cam gear and about the same on the crank timing gear. The crank gear"pulls down" on the belt, rotating the cam gear. At the same time it "pulls up" on the water pump gear.The timing belttensioner is placed in the circuit where the beltis not doing any work. Its sole function is to keep the timing belt "wrapped around" the pulleys to design specification, and no more. (This "wrapping" is readily apparent on the crank timing gear

- more than 180 degreees).

The balance belt tensioner, however, does indeedsit in the belt's working path tothe rear balance shaft gear. But the rear balanceshaft spins much more freely than thecam and water pump do, and, therefore,the balance belttensioner does not have to resist much tension force.

Because of the more or lessunifiedconfiguration of the tensioners, forcing more tension on onetends toloosen tensionthe other.

All of the above must be why Honda designed their non-friction-belt/tensioner systemthe way they did,and must alsobe why they wrote their belt-tensioning procedure they way they did (unfortunately,without elaboration).

IMO, adding tension beyond the smallamountnecessary to resista change in the belts' design paths, will only serve to place an unnecessary, counterproductivestretching force on the belt - possibly leading tothe belts'premature failure.

Although these belts stretch very little during operation, over time any working, moving belt will permanentlystretchtoa predictabledegree. This is why Honda recommends performing theirbelt tension procedure at specific intervals.

 

Yeah...in some since they are similar to a chain...it doesn't have to have a hundred pounds of force on it...it just needs enough to take out the slack. Of course enough tension to prevent those teeth from jumping.

But no fears...my springs were pretty worn and I just didn't have time to replace them.

It's not anywhere NEAR as tight as a drive belt...whoo...no way The t-belt is tight enough to keep it from jumping teeth but not so tight that it's torqing on the belt...in other words it's not pulling the belt more than enough to keep the slack out...

 

I see in one of the threads above, bcjammerx mentioned the balance belt tensioner spring appeared to be 'too long'. And the Honda said it was the correct part. I have done three timing/balance belts on my 93 Accord SECoupe. All three times, I got new Honda tensioner springs. The balance shaft tensioner spring is literally just hanging off the water pump bolt / upper spring retainer....its loose to the point it might fall off hitting a bump in the road. And that would be a mess under the timing cover. I bent the top spring hook (water pump end) into a tighter 'loop' and installed it. Has just enough tension to tug on the balance shaft tensioner. Been working on cars over 30 yrs (and this one over 17) and the spring appears to be too long to exert any real tension or cause the balance belt to stay tight. Should have take a pic of my modification but I just bent the spring hook enough to stay on its top mount. Will find the one I took out (put it in the box with the old tensioner 'just in case' its needed. I think the Honda spring 13407-P0A-000 is too long as supplied.