Dawg’s idler pulley project
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Topic: Dawg’s idler pulley project
Posted By: Dawg
Subject: Dawg’s idler pulley project
Date Posted: 16 January 2011 at 11:16pm
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I've decided to start building one of those idler wheels for the alternator belt. I have a belt on the car now that is much less than a year old and it's starting to squeal already. What a pain. So here we go. Because I already had the bearings and steel, I decided to make a dual bearing wheel. Should last forever that way.   Here is the shoulder bolt I made from a larger bolt. It's shoulder lets it act like an axle without "pinching" the bearings.  Next I need to make the bracket. Then I will trial fit everything to determine where I want the wheel to sit and how thick the spacer will need to be to center the belt. Ideally a simple washer will do. Stay tuned. ------------- You dream it up....I'll make it |
Replies:
Posted By: kharmata
Date Posted: 17 January 2011 at 11:41am
| Looks Heavy Duty. |
Posted By: Capt Fiero
Date Posted: 17 January 2011 at 1:08pm
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gesus man is that a pulley or a flywheel LOL. :) Ya I'd say that will last forever, and probably keep the engine running if it dies for a second. ------------- Capt Fiero 88 Fiero GT 5spd V6 Eight Fifty Seven GT V8 5spd. |
Posted By: Dawg
Date Posted: 19 January 2011 at 3:48pm
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Hehehe Perfect....next time the fuel pump dies I can just coast all the way home.....Bonus! The Dawg
------------- You dream it up....I'll make it |
Capt Fiero wrote:Posted By: Dawg
Date Posted: 19 January 2011 at 4:19pm
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I'm coming down the home stretch. I finished the bracket this afternoon but then realized the water pump is worn out. So installing the idler will have to wait till I get the new pump in there tomorrow. A note to Kevin: bolts are rated by their shank diameter's, not the head sizes....:) Here's the final assembly. Look closely and you will see that I slotted the mounting holes. This will allow some up and down adjustment which could come in handy. If I make more of these I'm considering slotting them even more. We'll see.   I can't wait to see it all finished. Anything like this that makes the car more reliable is such a feel good project. Wasn't expensive either. Well, after I pay for the the new water pump and alternator I may not feel quite the same....:) The Dawg ------------- You dream it up....I'll make it |
Posted By: kharmata
Date Posted: 19 January 2011 at 5:04pm
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Thanks Damien - I think I noted the head sizes from when I
wrenched it on. I didn't realize I left them on the picture in the post. LOL! As for your design - it looks great. 'My personal concern' would be the likely hood of twisting the thin cross bracket. With the small diameter standoff that looks to give it a fairly good mechanical advantage and may not like tight belts or quick throttle ups. I would suggest a wider base that the bearing sits on. But that's just from what I see in the pictures. Cheers |
Posted By: ZeroC
Date Posted: 19 January 2011 at 7:39pm
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i have the rodney dickman one on my car ....and honestly it works great for a week ..then i have to tighten the alt agian ...starts to get a lil squeek in the rain ...very annoying..im going to look at an actual tensionor now ...one a side note that looks well built :)
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Posted By: kharmata
Date Posted: 19 January 2011 at 7:52pm
So you are saying ... bolts don't have head sizes...? 
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Posted By: Dawg
Date Posted: 19 January 2011 at 9:16pm
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You could be right Kevin. On the day I'll have to keep an eye on the flexing for sure. It feels pretty darn rigid however. Like most days, I built it with what I had in the metal bin....:) It would be easy to modify either way. If you look at your diagram, which I used as a guide thank you, you mention drilling clearance holes for 17 and 15mm bolts. Those would be huge bolts indeed. I believe those bolts are 12mm actually. (shank diameter) ------------- You dream it up....I'll make it |
Posted By: kharmata
Date Posted: 19 January 2011 at 9:20pm
9/16 would also work.  Nothing to hurt by trying.
Just make it work however you can i say. 
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Posted By: Dawg
Date Posted: 23 January 2011 at 12:54pm
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I went to put the assembly on last night and I ran into a few snags. For starters, I think I'm going to have to back pedal a bit regarding the offset. With the water pump off, it sure looks like the bolts indeed are offset by quite a bit after all. I measured a little over 3/8". Originally I placed the bracket on the bolt heads and looked down to see if it was parallel to the belt. It seemed to be. I'm going to wait till I actually get it mounted before spewing numbers this time....:) A couple more snags came up also. I tried to remove the lower bolt with a large 3/8 ratchet and no way. I was pressed for time so decided to tackle it another day. I had already installed a new water pump and alternator and it was getting dark and spooky. Then I noticed the bolt right below it was not tight.  I've never been down this low on the motor. Could my problem be that the weight of the motor is sitting on the top bolt? I tried to tighten the bottom one but it appears to be bottoming out. I'll have to dig a bit when the sunshine returns. The Dawg ------------- You dream it up....I'll make it |
Posted By: kharmata
Date Posted: 23 January 2011 at 3:32pm
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ok - good to know, I will update my sketch too when you
measure an offset. Not sure why you can't get it out. Other than being in a really tight spot to reach. So too confirm the offset is inwards at the bottom right? or is it out...i forget. 
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Posted By: Dawg
Date Posted: 23 January 2011 at 8:29pm
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Yes, the bottom leg will need to be longer. The Dawg ------------- You dream it up....I'll make it |
Posted By: kharmata
Date Posted: 24 January 2011 at 6:00pm
Can you clarify - whats a little over 3/8"? Thanks. |
Posted By: Dawg
Date Posted: 24 January 2011 at 11:15pm
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I'm estimating 3/8. It really isn't that critical. The Dawg ------------- You dream it up....I'll make it |
Posted By: Dr.Fiero
Date Posted: 25 January 2011 at 5:41am
The entire weight of the engine bears on those two bolts! (on an early car) So, you need to prop it up on a jack (etc) if both are coming out at the same time. |
Posted By: Dawg
Date Posted: 04 February 2011 at 10:11pm
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I had some spare cash last week so I was able to fill up my Argon tank. This means TIG welding time! I modified the bracket to include a 3/8" offset between the two mounting points. It sure looks like a lot but the ruler don't lie. Hopefully this will lend itself to perfectly even pressure across the whole belt. Also, since I was making a fairly major modification anyway, I decided to add some rigidity as Kevin suggested. This came in the form of two gussets. Rather than upload the images in this message I simply updated the originals above. If it's nice this weekend, I'm going to try and get it all installed. The Dawg ------------- You dream it up....I'll make it |
Posted By: kharmata
Date Posted: 05 February 2011 at 9:18am
It sure looks custom now.  Nice Job!
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Posted By: Dawg
Date Posted: 05 February 2011 at 2:45pm
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Thanks! I'll get it right eventually...:) The Dawg ------------- You dream it up....I'll make it |
Posted By: kharmata
Date Posted: 06 February 2011 at 10:10am
Won't we all.
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Posted By: Dawg
Date Posted: 12 February 2011 at 2:52pm
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I was man handling my fancy project this afternoon and it suddenly occurred to me that the idler wheel itself was indeed a bit on the heavy side. You see originally I was going to make it out of aluminum. But I couldn't find a piece big enough in my goody bin. So a chunk of steel was used. Anyway.....here is what I did:  Nice and light now, and looks cool to boot....:) The Dawg ------------- You dream it up....I'll make it |
Posted By: kharmata
Date Posted: 12 February 2011 at 8:00pm
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Looks great. Was thinking about this suggestion for better cooling effects.
Cheers |
Posted By: Dawg
Date Posted: 08 March 2011 at 7:16pm
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Here's an update. I finally got the chance to install my idler wheel. Just for the record, the 3/8" offset looks good. *** EDIT - Lets call it 5/16" actually *** Michelle took it out to work a few hours ago and I didn't get a phone call to rescue her. So it must be working....:) I used the belt suggested by Kevin and I guess the wheel I made was bigger than a normal idler wheel because it was tight. I had to wrap the belt around the alternator pulley, then slide the belt onto the idler. This was the only way to get it on. I tried the next size up and it was way too long. Another win for the good guys! The Dawg ------------- You dream it up....I'll make it |
Posted By: kharmata
Date Posted: 22 March 2011 at 5:59pm
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Curious... Cheers ------------- Kevin 08GSXR1000 |
Did you install the idler with the orientation as shown in the picture of your fully assembled unit here on this page? ...if so - is likely why the belt was tight.Posted By: Dawg
Date Posted: 22 March 2011 at 7:17pm
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Nope....it's upside down on that image. The wheel is closer to the bottom leg. Have a look at the new and improved design on the tech session page. The wheel is even lower on that one. The Dawg ------------- You dream it up....I'll make it |