March serp belt pulleys with factory brackets

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rmchrgr

rmchrgr

Skate And Destroy
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Anybody use March serp belt pulleys with factory accessory brackets?

I'm asking because I took my Duster to the drags the other day and tossed a belt at 7,000 rpm. I started looking at the March stuff since they have V belt pulleys but they told me they don't really offer any advantage over regular v belt pulleys.

The guy on the phone suggested going to a serp belt set up using the factory style alternator bracket as the tensioner. Anyone do this? Just looking to prevent tossing the belt next time out.

Pics are good if you have 'em.

- Greg
 
I don't know anything about the March pulleys, but I spent the better part of 1.5 years chasing down what I thought was a pulley alignment problem, because my car would toss the belt on every pass. I used to go racing with a minimum of 4 extra belts on hand every race. A lot of times I would not lose the belt, it would just pop off and hang around the water pump...but other times it would get stuck between the balancer and the block and get fried. When I would get down to my last belt I would have to go home :banghead: (only happened once that I ran out of usable belts)...

Anyway....LONG story short, my issue was not all in the pulley alignment...I solved the issue by using a thicker/stiffer and wider belt than normal. I forget the exact size, but I went up from like 0.8cm to 1.1 or 1.2cm width. Problem solved.
 
flyfish said:
.LONG story short, my issue was not all in the pulley alignment...I solved the issue by using a thicker/stiffer and wider belt than normal. I forget the exact size, but I went up from like 0.8cm to 1.1 or 1.2cm width. Problem solved.
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Huh. I used a Dayco 7460. Not sure how wide its supposed to be since it's kinds destroyed.
Didn't realize there were wider V belts available.

I also thought about going to a shorter belt?
 
flyfish said:
.LONG story short, my issue was not all in the pulley alignment...I solved the issue by using a thicker/stiffer and wider belt than normal. I forget the exact size, but I went up from like 0.8cm to 1.1 or 1.2cm width. Problem solved.
Click to expand...

Huh. I used a Gates 7460. Not sure how wide its supposed to be since it's kinds destroyed.
Didn't realize there were wider V belts available.

I also thought about going to a shorter belt?
 
flyfish said:
.LONG story short, my issue was not all in the pulley alignment...I solved the issue by using a thicker/stiffer and wider belt than normal. I forget the exact size, but I went up from like 0.8cm to 1.1 or 1.2cm width. Problem solved.
Click to expand...

Huh. I used a Gates 7460. Not sure how wide its supposed to be since it's kinda destroyed.
Didn't realize there were wider V belts available.

I also thought about going to a shorter belt?
 
So anyone else have any input on this question?

Got a shim kit and a new V belt put on. It's all lined up and square but I am still thinking about the serp belt idea with the factory brackets. Just seems like an easy deal but it might look weird on an older engine.
 
I would have thought try a narrower belt so its sits deeper in the pulley. My brothers 451 kept tossing belts. We tried a narrower belt problem solved.
 
moparspares said:
I would have thought try a narrower belt so its sits deeper in the pulley. My brothers 451 kept tossing belts. We tried a narrower belt problem solved.
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I got a different brand belt, a Dayco top cog.

Before the belt flew off, I had never noticed that the belt was twisted because of pulley misalignment and a poorly machined water pump pulley that was thicker on one side of the groove than the other. Only after I really looked at it did I see it was crooked. I spent a lot of time lining up the pulleys and getting them as close to perfect as possible.

Serp belt has more area and flatter grooves, just seems like it would probably be more likely to stay put at 7 grand.
 
I'm running March serpentine pulley's with stock brackets and have had no problem, but I also don't spin it past 6500. It's a street car more than race car but I still run the crap out of it. Have approx. 15,000 miles on it with the 1st belt I started with and it has never tossed it and still looks like new.
 
fishy68 said:
I'm running March serpentine pulley's with stock brackets and have had no problem, but I also don't spin it past 6500. It's a street car more than race car but I still run the crap out of it. Have approx. 15,000 miles on it with the 1st belt I started with and it has never tossed it and still looks like new.
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Sounds cool. I'd like to see pics if possible!
 
I saw a dude with a skateboard wheel on the end of a stud acting as a tensioner (although it was static, doesnt move) he put it against the belt on the outside of the belt path as belts like to grow there when they get humming. I didnt ask what it did as I kinda figured it out by looking at it. Doing some math, I figured the 54mm skateboard wheel would rotate at ~28000 RPM at cranks 7000 RPM, with a belt speed of about 233 ft/sec. really was a simple idea, just find a 5/16 bolt that you could extend out and bolt a skateboard wheel to.
 
I have spun my 360 to 7K with the March serpentine pullies on a stock Alt. bracket, the P/S is on the March bracket set up. The 6 rib belt is 1 inch wide.
 
rmchrgr said:
Anybody use March serp belt pulleys with factory accessory brackets? I'm asking because I took my Duster to the drags the other day and tossed a belt at 7,000 rpm. I started looking at the March stuff since they have V belt pulleys but they told me they don't really offer any advantage over regular v belt pulleys. The guy on the phone suggested going to a serp belt set up using the factory style alternator bracket as the tensioner. Anyone do this? Just looking to prevent tossing the belt next time out. Pics are good if you have 'em. - Greg
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Would these be some thing to consider ?

http://www.ebay.com.au/itm/VALIANT-...=AU_Car_Parts_Accessories&hash=item2ed59cecf9
 
fishy68 said:
Have a ton of pics of the car but nothing really showing the serpentine setup good. I'll take some tomorrow and post them
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That would be awesome Tracy, looking forward to it.

And to 67GT, thanks for the link but I don't need a gilmer belt setup. Perhaps if I was running a supercharger but I just have a little old alternator.

I ran the car a little this morning and watched the fan belt. You can see it vibrating between the alternator pulley and the crank pulley at idle and then it smooths out as the revs climb. I don't think the vibration necessarily goes away either, it's just going faster. Not sure if that's right or not. It's curious what you see when you start really looking at this stuff.

Car tends to vibrate though when it's cold like it has a miss but there's no misfire. It's just high strung I guess. The belt is tight, it only deflects a little when there is tension on it. There's probably a wobble in one of the pulleys.

The March stuff is looking better and better.
 
rmchrgr said:
.

.............

I ran the car a little this morning and watched the fan belt. You can see it vibrating between the alternator pulley and the crank pulley at idle and then it smooths out as the revs climb. I don't think the vibration necessarily goes away either, it's just going faster. Not sure if that's right or not. It's curious what you see when you start really looking at this stuff.

................
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My car did this same thing....I'm just sayn, I would try a wider belt before you drop $$$ on a March setup, unless you are just trying to justify the cost of buying the March setup. Take your belt into Autozone, hand it to the parts guy and tell him you want a belt like this (V-belt, approximately the same length) only wider. You should be able to get 1 or 2 different sizes to try out. New V-belts are only 5-10 bucks and a March setup is over 350 bucks...I know what I would try first.

On the RPM front, mine will stay on the car at 7k, although I think surviving the converter flash is probably what's hardest for the belt....especially with an 8" converter that flashes to 5000+ almost instantly (using my car as an example). JMO.
 
flyfish said:
My car did this same thing....I'm just sayn, I would try a wider belt before you drop $$$ on a March setup,
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I get what you are saying but just by looking at it, the current belt seems to be a tad wider than the one I had in there before (Dayco top cog vs. Gates bottom cog). It also appears to sit flatter in the groove. Could be just the outside of the belt, not sure. Again, I've read where people suggested to go with a Dayco top cog belt over other brands, perhaps this is why.

Regardless, there does not appear to be much extra room for a wider belt to sit in the pulleys without riding up on top of the groove.
 
Just looked up the 3 pulleys from March - crank pulley is around $89, WP is $95 and the alternator is $56 which = $240. Pricey for a set of 3 pulleys? Of course, but, all the extra belts can add up quick @ $12-18/ea. A single 45" serp belt would cost around $30-40 depending where you get it so you're all in for just under $300 bones.

Based on watching the belt vibrating this morning, I guarantee it will come off again at the wrong time. Thinking about this scenario from that angle, $300 seems reasonable to correct an age old problem that could potentially cause way more than $300 worth of damage from tossing a belt at high rpm.

Plus, I can always reuse the pulleys on another engine so it's basically a one-time investment.

Just a better mousetrap I guess. New cars have not had v belts for years.
 
Ram. Are V belts even in stores around us anymore?
 
rumblefish360 said:
Ram. Are V belts even in stores around us anymore?
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Yeah, definitely. I just bought the last belt at Car Quest here by me in Huntington. Still plenty of cars on the road with V belts but yes, serp belts are of course more common now.

Another reason to switch to a serp belt, v belts are probably going to start getting harder to find in the coming years.
 
More looking on the internets, found this on a brand-X page but this is pretty close to what I'm looking to do, albeit without the chunky billet brackets like this one.
57203d1229707850-how-do-i-run-serpentine-belt-w-standard-pump-no-p-s-waterpump2.jpg
 
Here's 3 pics Greg. With it all put together that's the best I could do. In the third pic it looks like the belt isn't running straight. Must be just the way I was holding the camera because it is running straight
 

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fishy68 said:
Here's 3 pics Greg. With it all put together that's the best I could do. In the third pic it looks like the belt isn't running straight. Must be just the way I was holding the camera because it is running straight
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Looks great. Thanks for taking those pics, I appreciate it. Sometimes its hard to visualize what it would look like without them.

Which belt did you use? Do you know what size it is? I have a 46" belt on the car right now with the Denso alt which seems to work well. It charges and cools fine under normal driving conditions.

I tend not to like mixing outwardly appearing modern stuff like this on an older car and I try to keep the car looking vintage but sometimes you gotta make a concession in the name of better performance and reliability. The 100% vintage vibe is already out the window anyway on my car with the Denso alternator, K&N filter and giant aluminum radiator.

I'm pretty much sold on this deal. I realize the cost seems fairly inflated for what the parts are and what they do, but again, I believe it's a better mousetrap. Even the brand new pulleys I have on there now have some run out which makes it almost impossible to eliminate the belt tossing issue. You can align them until you're blue in the face but the run out is still gonna make them wobble which obviously increases the potential for tossing the belt again. I would think (hope) there is negligible run out on billet aluminum pulleys.

Thanks again Tracy!
 
Glad to help Greg. I have a Napa right down the road and I used their brand of belt which the counter guy said was made by Dayco. The instruction sheet that came with the pulley's said to use a 45-1/2" belt and I could get it on but it was real tough. Had to take out the alternator adjustment bolt to let the alternator over far enough to get it on. I swapped it for a 46-1/2" belt and the alternator adjustment is perfectly centered in the adjustment range and no longer have to remove the alt adjustment bolt to get the belt on an off.

I didn't check them with a dial indicator for runout because they look good by the naked eye. If there is any runout it's negligible
 
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