Argo clutch center to center distance, belt too tight?

[olargo]

Hi all
There was a thread on here regarding argo center to center distance between clutches, but I cannot find it. Any help would be appreciated.
I have a '99 Vanguard 2, model 699-55. The transmission cannot be shifted unless I shut off the engine. The idle is a slow as I can set it. It has the proper belt, 125-56 and it is proper width. Each clutch is functioning properly and not sticking.
At idle, the drive clutch is not gripping the sides of the belt - there is approx. 1 mm of space on each side of belt to the sheave, at idle.
It would appear to me that the belt is gripping the inner diameter of the drive clutch just enough to keep strain on the driven clutch.
I am contemplating removing the engine and trans so that I can elongate the trans mounting holes in the mounting base, to decrease the center to center distance. I will make some type of solid stop, or adjustment so that I can fine tune the center distance.
I understand that the quick fix would be to buy a new clutch with a bearing that would permit the belt to spin freely at idle, but I'm too cheap (frugal?!) to do that...I'd much rather spend untold hours removing and re-installing the power pack!
Does any one have advice or another idea that may help?
Thank you in advance.

[Mike]

If you get your hand around the top and bottom of the belt between the two clutches, how much can you move the top and bottom of the belt in, towards each other? As a general rule, you should have about 2" of deflection. Your Vanguard may have slightly different specifications.

If the belt is new it may not want to let loose as easily. Also, if the belt is the wrong size (too short) then it could possibly be too tight. Otherwise, I would find it hard to believe that the belt would be too tight. You say that the drive clutch is not engaging and gripping the belt at idle. Is the belt still turning at idle? Is the driven clutch turning?

[olargo]

Hi Mike
Thank you for your reply.I will have to see how much deflection I have.
Correct - the drive clutch is not engaging/gripping the sides of belt. At idle, the driven clutch is turning slowly. At other times, for example, forward motion stopped on a slight grade, the driven clutch does not spin but at idle there seems to be enough 'strain' on the belt to prohibit shifting the trans even with the brakes on. When I shut off the engine, I can see that slack is created on the top run of the belt.
I even went so far as to 'shave' the ribs on the inner diameter of the belt in an attempt to slightly increase the belt inner diameter, to create some clearance around the driver clutch's smallest diameter. Thought I'd sacrifice the belt just to see if it would help...but no luck.
I find it difficult to believe that the smallest inner diameter of the driven clutch can grip the belt enough to create the strain that exists at idle, due to the relatively small surface contact area involved - but I see it happen.
Is it possible that there would be slight variation in belt length from one belt to the next, within one belt part number? The belt has about 100 hours on it. I have a new spare - maybe I should put it on and try it to see what happens.
It is my understanding that the trans should shift as smoothly and easily while the engine is at idle as it does when the engine is off - is this correct?

[moos-a-boo]

I posted about two years ago about the center to center distance between the clutches, my belt was LOOSE. It was on a conquest, different engine and belt, I think.. My opinion, you need to pull both clutches and clean and inspect. Rock Doctor posted couple videos on this site that helped me and my friends with clutch tear down, maintenance, adjustment. Please try this before you modify the bolt holes.

[olargo]

Thank you for the advice. I've had the driven clutch apart and cleaned/lubed it, bit not the driver. I will do this.

[ARGOJIM]

Thank you for the advice. I've had the driven clutch apart and cleaned/lubed it, bit not the driver. I will do this.

The trans in the pre Avenger/ Frontier models has straight cut gears so it never shifts easily, ie. shut off reverse to high there will be some bind when shifting, minimal but some as the gears mesh. A rolling machine stopping with the brakes on to shift can be a pain if not impossible as the gears need to slightly move to mesh.
I've seen some Conquests with rotten power packs in them so check that, but unless the engine is falling forward the force should suck it in and not push it out.

It sounds, without full info, to me as if you have a Briggs that needs to have the "forced" idle adjusted. This is common to some Van.s and have a factory provision for it. If you can't get it to stall when adjusting idle I'd suspect that. 100 rpm will make all the difference in those.

[olargo]

Thank you Argojim - I was hoping you'd weigh in! Is there any other info I can provide?
I should have mentioned-my machine has a B&S 16hp. I will read up on idle adjustment for this engine.
With that being said, when you mention 'rotten power packs': as a machinist, I understand tolerancing, and sometimes when working on my own stuff, I wish I didn't know what I know about the subject. Maximum material condition, for example - it's really nice when it works in your favour, but then not so nice when it doesn't. Case in point: I have wondered - are the hole locations in the power pack 'frame' at one extreme end of it's tolerance, and the holes in the trans and/or engine are at the other extreme...and are the holes diameters on the large end of tolerance? Are they straight?! And then when the power pack was assembled, were things set/tilted 'j u s t' enough to put the center to center distance slightly out of tolerance? Yeah, yeah, yeah I know - it was ENGINEERED and TOLERANCED to perform flawlessly regardless of however it was assembled, and whenever it was assembled - day shift, afternoon shift, Monday morning or Friday afternoon! No disrespect intended to the fine employees of ODG - a good friend of mine used to work there. It's simply that sometimes the tolerance stack-up can lead to problems.
I will look into the idle issue.

[msafi65]

I've found that if you can pinch the belt around the drive center and pull it away from the driven clutch. You need at least 1/16" clearance at the center of the drive clutch. Any tighter than that and belt will drive at an idle and usually squeal at idle. 3/16" is probably not to loose but getting there. Most Argos have to have idle set very low to shift without clashing gears.