Ingersoll Rand Gas Compressor Issues...help please

[maxpower_hd]

OK. Some of you may have seen parts of this in another thread. I got a model 2475 T30 Ingersoll Rand Gas compressor given to me but it was missing a lot of parts. Basically it was a tank and the compressor head.

I got a parts list thanks to another thread and a member who was kind enough to post it.

I ended up buying after market or different brand parts than IR. I got the unloader valve, throttle control valve (not attached to engine yet), relief valve, engine, engine pulley, belt, regulator and misc plumbing. I got it together enough to run it and prove it builds air. I still have some final plumbing to do but for now I just have a hose going from the head tot he tank input until I work out the bugs.

My issue is the belt will not stay on the pulleys. From the parts list it looks like there is supposed to be a belt tensioner and/or tightener on this that I don't have. I have exhausted my searching skills. The closest I can find to a picture of this tensioner is a threaded rod with a bolt welded to it. I am guessing that adjusts the actual tensioner but I have no way to know what the original one looked like. The parts drawing does not show this part of the compressor.

Does anyone happen to have one of these that could maybe take a photo for me so I can see what I need to do to make or buy a tensioner assembly?

Here is a pic before I put all the additional parts on it and got it running for reference. I don't have one of the belt side yet but since it is missing what I need I'm not sure it would be all that helpful anyway.

Thanks for any help you can offer.

 

[jallyn]

So the engine is mounted on the frame. The long slots on the frame are for sliding the engine over to set the belt tension. Are you not able to slide the engine over any further to tension the belt?

 

[Monkey Milk]

Its not a tension problem, that's an alignment problem with the pulleys. Check to make sure you're running true.

 

[maxpower_hd]

There are slots and I am able to slide it back but I am not sure it is staying tight enough. I have checked the alignment but I will do a better job to make sure I am not off a tad. I used a level but I will try a straight edge instead. It comes off mostly during idle. I also didn't re-check it so it is possible it moved a little.

I may also build a better mount plate to see if I can slide it more. So is there not a tensioner? I'm curious to know what it looks like and if I need it.

Thanks for the input. I will double check those two things tomorrow night since I have to work tonight.

Thanks again.

 

[Monkey Milk]

Some machines have the tensioner, both of mine don't. It fairly easy to make but I just put a screw type bottle jack between the motor and pump. Keep in mind if you do it this way you could be exerting a lot of force and not realize it.
Another thing it could be is the v-belt is to large to fit in the pulley and jumps out when there is slack.

 

[jallyn]

Yeah, check alignment with a straight edge. Once you are sure it is straight tighten it by sliding the engine over. If you can't get the proper tension and run out of slot, buy a smaller belt so you can.

 

[maxpower_hd]

OK. I double checked the alignment with a straight edge and it is dead on. Unless we are looking for thousandths of an inch... I cannot see any misalignment.

I am not quite at the back of the slots with the engine. I have about another 1/2" to go but I can't physically pull any tighter. Maybe if I get someone to help me so I one can tighten while the other one pulls or something that might help a little. Or maybe I can try the bottle jack idea. I don't have one small enough though I might have to try a block of wood a little too big and tap it in with a hammer like a wedge.

The belt will jump out in either direction so that also leads me to believe it may not be related to alignment. I would think it would jump out the same direction every time if it were.

The belt is the size IR specifies so it is a correct match for the compressor side pulley which is where it is coming off. It is perfectly flush to the top of the pulley.

The manual for this model with my engine lists a belt tensioner and a tightener clip so I'm assuming it has one for a reason. I have found literally hundreds of pics on line but NONE of them show the area I need to look at. That is why I was hoping someone on here might have the same one as a reference. Mine was originally equipped with a Honda GX340 11 HP. The only part I was able to find a pic for was the threaded rod used to adjust the tensioner which I can easily make. It is the where and how it mounts and works that I need the most. I may end up just having to invent one on my own I guess. I don't even know if it is supposed to apply pressure to the top or bottom of the belt.

Thanks for your help. I will update when I figure something out so it might help someone else having this issue.

 

[Monkey Milk]

Is the pulley the type that has a sheeve? 3 bolts to draw in the taper on the pulley? Did you spin the pulley around make make sure its straight on three different points? How's the pump? turns without hardspots? If that's all good then it would have to be belt tension.

The tensioner just a bracket the connects to one of the bolts on the engine mounting points. Has a long screw (all thread)and another bracket the hooks the end of the tank mounting plate and a nut. Tighten the nut which pulls on the screw that is connected to the motor.
Hope this helps.

 

[Monkey Milk]

Or another members way

or

this for electric motor

 

[maxpower_hd]

That turnbuckle idea is perfect! I already have them too. Wish I thought of that! That's why I come here. Thanks for that link.

It is also the sheave type and no I didn't check it in three spots. Maybe I happened to check it twice in the same freekin spot! That might be it too or a combination of both that and tension I suspect now. It will stay on at higher rpm but seems to jump up and down a lot. I will disconnect the belt and run the engine and see if I have a wobble in the pulley with a piece of soap stone held against it if it isn't obvious enough for me to see. Then I will tighten with the turnbuckle. If all else fails I will build the tensioner.

Thanks for the ideas guys. At least now I have somewhwere to go with this.

 

[maxpower_hd]

Here is another update. I haven't had a lot of time but I did work out some bugs last night. I think I have more than one issue I am contending with. I was able to play with the alignment some more and finally got the compressor to run without throwing the belt. It will run as long as I need at any speed I set it at. However, now it will come off when changing speeds.

I got the belt a little tighter but still not as tight as it should be. So I am building, or having the machine shop at work build for me, a tensioning block that will mount in front of the engine with threaded rod going through it so I can easily tighten the belt by sliding the motor back with the threaded rods. It will serve more than one purpose. It will also, I think, help keep the engine from cocking one way or the other and will keep the tension under load once the desired tension is reached. Not that that part was much of an issue anyway.

Next, I did rig up a pulley tensioner which helped but I couldn't really get it mounted quite where I needed it. So now I am thinking I need to make and install a round rod at the output side of the compressor pulley, where the belt will come off, much like a snow blower or lawn tractor. So during sudden speed changes when the belt momentarily jumps it will hit the guide and not come out of the pulley enough to pop off. But it won't ride on the guide regularly either. My theory is that during the sudden speed changes I am getting slippage due to the two pulleys changing speeds at a slightly different rate because there is a moment when there is pressure still in the head causing some added friction on the compressor side. So I think it is that moment when the belt tries to pop off.

Lastly, the material on the belt I have now is sort of a cloth material. It is actually a lawn tractor belt. The material on the "compressor" belt is rubber, but the wrong length, so I can't use it. But when fitted by hand in one pulley it seems to grip a lot tighter. So I think I would get less slippage with that material. So I am going to have to order one of those in the right length.

I'll let you know how I make out in the end.

Thanks again.

 

[jallyn]

There are a couple options that you might consider to properly tension the belt...

Find a way to use a large pry bar to push the base of the engine over as a helper snugs the engine bolts. You can stack wood or metal to create a pushing point or weld a bar just inside the engine base and pry against that.

You can weld a plate with a couple threaded holes just inside the engine base. Use a couple bolts in the threaded holes as jack bolts to push the engine over tightening the belt. Snug down the engine.

 

[maxpower_hd]

There are a couple options that you might consider to properly tension the belt...

Find a way to use a large pry bar to push the base of the engine over as a helper snugs the engine bolts. You can stack wood or metal to create a pushing point or weld a bar just inside the engine base and pry against that.

You can weld a plate with a couple threaded holes just inside the engine base. Use a couple bolts in the threaded holes as jack bolts to push the engine over tightening the belt. Snug down the engine.

That is basically what I am doing. Only I am using an aluminum block and bolting it down instead of welding it and drilling/threading holes through it for the jack screws. This alone may solve my problems but if not I will add the belt guide as well.

Thanks for the idea.