Hey guys, looking for all the parts that I'm going to need for my daughter's Fiero once I have it pulled, and it occurred to me that I was never too pleased with the old belt system on my 84 Fiero. It was ALWAYS squealing... like, constantly. I know the 87 Fieros had the newer belt system which also included a belt-tensioner. Is there any reason why I shouldn't expect that I can simply upgrade the 84-86 (specifically my daughter's 85) with the new belt system?
I'm guessing I'll need the following:
- belt tensioner - new water pump w/ 87 pulleys - new alternator w/ newer pulley - belts
Anything else I'm missing? Is there anything that's going to prevent me from doing this?
By the sound of it you want a brand new car when your finished. Haha.Did Rodney D. not have all those bits? If it was v6 i could help as I've got spares of most original parts.
By the sound of it you want a brand new car when your finished. Haha.Did Rodney D. not have all those bits? If it was v6 i could help as I've got spares of most original parts.
Haha, yeah... pretty much. We're not just fixing things, every single mechanical component will be gone through. Everything will be "like new."
I have Rodney's kit for my V6 too... I installed it years ago, but totally different concept for the 84-86. If I'm not mistaken (I need to look), I think it uses a V-belt for both...
Is there any reason why I shouldn't expect that I can simply upgrade the 84-86 (specifically my daughter's 85) with the new belt system?
"Simply"? No.
Finding a way to effectively deal with loose V-belts on the '84-'86 duke has been a topic of discussion many times here over the years. I don't recall a viable solution ever being offered.
Well, the '87+ 2.5 belt tensioners aren't available anywhere that I'm aware of at this time, so that will make it harder.
The AC compressor was also on the same belt on the '87+, so you would need to replace that as well, if equipped.
I don't have any late 2.5s around to look at, but the brackets likely have a different offset for the components as the early models ran 2 belts and the later ones only ran 1.
It is certainly possible to convert to a single auto-tension belt. Unless you can find a complete take-off set of accessories and brackets it will probably require a lot of custom fab work.
Finding a way to effectively deal with loose V-belts on the '84-'86 duke has been a topic of discussion many times here over the years. I don't recall a viable solution ever being offered.
quote
Originally posted by FieroJimmy: Unless you can find a complete take-off set of accessories and brackets it will probably require a lot of custom fab work.
Thanks guys, I guess that's kind of what I'm asking. Are the engine blocks the same at least from 86-87 so that, should I find an 87+ motor, I can basically swap everything over using the newer parts? If that's a yes, then that's probably the direction I'm going to try to go...
Are the engine blocks the same at least from 86-87 so that, should I find an 87+ motor, I can basically swap everything over using the newer parts?
I believe there's more to it than that... otherwise I suspect it would've been an option mentioned here numerous times over the decades. The Ogre probably knows a reason or two why it wouldn't work.
[This message has been edited by Patrick (edited 06-10-2023).]
Thanks guys... it seems that the engine casting itself has actually changed to be able to support the serpentine belt system. I did find an engine for sale that I was just going to buy so I could take all the stuff off of it, but from the link that Shemdog posted (which I apparently responded to many years ago), Ogre states the block is actually different in this case, and aside from all the bolt on stuff, lacks the necessary holes to install the tensioner. So... I guess that's that. It can definitely be done (appears to be a single bolt), and we can modify the bracket to support it... but the juice is definitely not worth the squeeze as they say...
Ok, so, I never updated this thread, and figured I would do it now, while also asking a question (next post).
I was able to upgrade to pretty much everything on the 87-88 engine... this is what I did (I'll update this later with more detail when I have time):
- Kept the upper and lower alternator bracket for the 1985-1986. That's because I cannot install the 87-88 belt tensioner on an 84-86 block. So... the alternator becomes the belt tensioner.
- I used the waterpump pulley from a 1987-1988 (6-groove serpentine pulley)
- I swapped out the pulley on the alternator with a 6-groove serpentine pulley from an 87-88. (I actually upgraded to a CS130 and installed a decoupler pulley)
- I replaced the crank pulley and hub with a brand new General Motors harmonic balancer for a 1989-1991 Iron Duke, which I was able to find online. (but you can just swap over the 87-88 6-groove pulley and hub.
- I used 1987-1988 A/C compressor brackets, and installed an 86+ L4 A/C compressor with a 6-groove serpentine pulley.
Although it looks bad, it's actually the same surface area as the previous V-belt system had. I'm looking for a solution to install somee kind of idler pulley to give me a little bit more surface area on the crank.
So, quick question... I was looking on some website about Iron Dukes, and found this image of a 1991 Iron Duke from a Chevy S-10 Pickup.
Right there in the lower left-corner of the engine block, there is a belt tensioner. I'm wondering how this installs, and what the brackets look like... anyone have any idea?
Although it looks bad, it's actually the same surface area as the previous V-belt system had. I'm looking for a solution to install somee kind of idler pulley to give me a little bit more surface area on the crank.
I think you're absolutely going to need an idler pulley or tensioner mounted on there. I suspect with any kind of a load on that belt (ie A/C turned on and/or heavy electrical draw), especially if/when wet, that the belt will slip badly.
[This message has been edited by Patrick (edited 10-13-2024).]
So, quick question... I was looking on some website about Iron Dukes, and found this image of a 1991 Iron Duke from a Chevy S-10 Pickup.
Right there in the lower left-corner of the engine block, there is a belt tensioner. I'm wondering how this installs, and what the brackets look like... anyone have any idea?
Oh wow, that's fantastic! Thanks Patrick! That thing looks like it can easily be cut (at the bottom) and installed in place of the lower alternator bracket!!!
Looking more at it, I would need to modify this bracket, and the tensioner itself can't be used as a tensioner (so to speak), and that the alternator still needs to be used as the thing that "tensions" the belt, but I have a spare stock bracket, and I'm wondering if I can't simply just drill a hole in the spare lower bracket I have, and install a tensioner on there?
I'm going to have to try to find one of these guys... but It may be as simple as drilling a hole in one of my spare brackets, and then a smaller hole for the tensioner mount, and then using it all the same. The rest of it doesn't seem to add any strength to the tensioner part... just to hold the alternator.
[This message has been edited by 82-T/A [At Work] (edited 10-13-2024).]
I would need to modify this bracket, and the tensioner itself can't be used as a tensioner (so to speak), and that the alternator still needs to be used as the thing that "tensions" the belt...
If that bracket seen in the image could be adapted to fit on your duke, why couldn't the tensioner be used as it was designed to be used for? What am I missing?
If that bracket seen in the image could be adapted to fit on your duke, why couldn't the tensioner be used as it was designed to be used for? What am I missing?
Difference is, in the S10, the alternator sits really high up on the engine, since it's in a rear wheel drive configuration. In the Fiero, it sits down low. So I'd have to cut the S10 bracket to lower the alternator.
But I don't think that's totally what you're asking. I suppose I COULD use the dog-bone bracket from the 88 engine that I had (if I can still find it), and then use the bracket. I think it was quite literally just a steel rod with a hole on either side. I can't remember. It would require me to have to get another new CS130 alternator though. Not a huge deal though, because I can use this one for my 87. Something to think about.
Difference is, in the S10, the alternator sits really high up on the engine, since it's in a rear wheel drive configuration. In the Fiero, it sits down low. So I'd have to cut the S10 bracket to lower the alternator.
Cutting the S10 bracket was what I was actually thinking of, as all you really need is the lower part to mount the tensioner to... however, it appears that the lower part of the bracket is basically just hanging there (it's hard to tell), and that the upper part of the bracket is required in order to bolt to the side of the head (as indicated with red arrows) for support. Hmmm...
Cutting the S10 bracket was what I was actually thinking of, as all you really need is the lower part to mount the tensioner to... however, it appears that the lower part of the bracket is basically just hanging there (it's hard to tell), and that the upper part of the bracket is required in order to bolt to the side of the head (as indicated with red arrows) for support. Hmmm...
The lower part of the bracket attaches to the two bolts on the block (look at my picture), where the Fiero's lower alternator bracket attaches to. Those two bolt holes are still there.
I basically just need to find a way to combine this...
and this...
They both use the same bolt holes in the bottom. My thought was to take both of them, bolt them together (back to back) when / if I can find one, and then put it on a band saw and cut them perpendicularly. Now... I'd have the top part of the Fiero's lower alternator bracket, and the bottom part of the Chevy S-10 alternator and belt tensioner bracket, and then take them to someone who knows how to weld aluminum, and ask them to weld those two halves together to get me what is basically a lower Fiero alternator bracket with a belt tensioner attached to the bottom of it.
You posted that while I was hunting for the following image. I was wondering where the bottom two bolts went, but your image above answers that. This is the kind of stuff I enjoy figuring out, but it would be so much easier if it was all in front of me.
Ok, so, I never updated this thread, and figured I would do it now, while also asking a question (next post).
I was able to upgrade to pretty much everything on the 87-88 engine... this is what I did (I'll update this later with more detail when I have time):
- Kept the upper and lower alternator bracket for the 1985-1986. That's because I cannot install the 87-88 belt tensioner on an 84-86 block. So... the alternator becomes the belt tensioner.
- I used the waterpump pulley from a 1987-1988 (6-groove serpentine pulley)
- I swapped out the pulley on the alternator with a 6-groove serpentine pulley from an 87-88. (I actually upgraded to a CS130 and installed a decoupler pulley)
- I replaced the crank pulley and hub with a brand new General Motors harmonic balancer for a 1989-1991 Iron Duke, which I was able to find online. (but you can just swap over the 87-88 6-groove pulley and hub.
- I used 1987-1988 A/C compressor brackets, and installed an 86+ L4 A/C compressor with a 6-groove serpentine pulley.
Although it looks bad, it's actually the same surface area as the previous V-belt system had. I'm looking for a solution to install some kind of idler pulley to give me a little bit more surface area on the crank.
I don't believe in this picture there is insufficient belt wrapped around the crankshaft pulley to prevent slippage under heavy load. IIRC there must be a minimum of 50% wrap to be effective.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
I don't believe in this picture there is insufficient belt wrapped around the crankshaft pulley to prevent slippage under heavy load. IIRC there must be a minimum of 50% wrap to be effective.
looking at this the only thing that would need to be done is to make an idler that attaches to the block off plate to wrap it around the crank and ac more if needed I would probably make a new plate since it's pretty easy to fab and could be made much thicker for modifications
looking at this the only thing that would need to be done is to make an idler that attaches to the block off plate to wrap it around the crank and ac more if needed I would probably make a new plate since it's pretty easy to fab and could be made much thicker for modifications
You and I think a lot a like... I was looking at some alternator brackets on eBay the other day... and discovered some bracket that allows you to add a second (or third) alternator to a Tahoe or something... and it occurred to me, bolting it to the block-off plate area MIGHT just work.
The biggest problem I see is that the bolt holes for the block-off plate are much, much smaller diameter than what was used in the 87-88 for the actual tensioner. The difference of course is that it's three bolts (87-88) compared to 4 bolts (84-86). My concern is the tension that might be put on these bolts, or even still, the plate underneath it, and the holes that the bolts go into. These bolt holes are not well supported, and I don't think they were originally designed to take any kind of real tension, rather... just to support a block-off plate. But I could be wrong... because I think in F/R applications (like the Chevy S-10), it supported a front-mounted water pump, which most certainly was under tension... so I don't see how that would be any different then (I apologize, I'm thinking out loud here).
My only concern is the top two bolts, and potential clearance needed for a plate to go on that. If I had a metal break or bending system, I could probably make a bracket that would sit on top / above that.
How hard would it be to then simply weld a nut on the underside of a plate to hold an idler pulley?
You might be right Sleek... I am really thinking this is the answer, and possibly the easiest to do. I'll have to hit harbor freight, as I don't have a metal cutting band saw either... I really think this might work...
EDIT: I just bought a spare 1984 Fiero 2m4 coolant block-off plate from eBay, so I don't have to mess too much with the one already on the motor. I should get it in a week, and by that point, I'll have everything else I need. Harbor freight actually has several breaks on display... so I may sneaky go in there and just use one while I'm there, hahaha...
EDIT #2: I just bought two 1/8th inch steel plates (8" x 10") which I'll use as the bracket.
Have I told you recently how much I love you, man?
[This message has been edited by 82-T/A [At Work] (edited 10-17-2024).]
Originally posted by 82-T/A [At Work]: You and I think a lot a like... I was looking at some alternator brackets on eBay the other day... and discovered some bracket that allows you to add a second (or third) alternator to a Tahoe or something... and it occurred to me, bolting it to the block-off plate area MIGHT just work.
The biggest problem I see is that the bolt holes for the block-off plate are much, much smaller diameter than what was used in the 87-88 for the actual tensioner. The difference of course is that it's three bolts (87-88) compared to 4 bolts (84-86). My concern is the tension that might be put on these bolts, or even still, the plate underneath it, and the holes that the bolts go into. These bolt holes are not well supported, and I don't think they were originally designed to take any kind of real tension, rather... just to support a block-off plate. But I could be wrong... because I think in F/R applications (like the Chevy S-10), it supported a front-mounted water pump, which most certainly was under tension... so I don't see how that would be any different then (I apologize, I'm thinking out loud here).
My only concern is the top two bolts, and potential clearance needed for a plate to go on that. If I had a metal break or bending system, I could probably make a bracket that would sit on top / above that.
How hard would it be to then simply weld a nut on the underside of a plate to hold an idler pulley?
You might be right Sleek... I am really thinking this is the answer, and possibly the easiest to do. I'll have to hit harbor freight, as I don't have a metal cutting band saw either... I really think this might work...
EDIT: I just bought a spare 1984 Fiero 2m4 coolant block-off plate from eBay, so I don't have to mess too much with the one already on the motor. I should get it in a week, and by that point, I'll have everything else I need. Harbor freight actually has several breaks on display... so I may sneaky go in there and just use one while I'm there, hahaha...
EDIT #2: I just bought two 1/8th inch steel plates (8" x 10") which I'll use as the bracket.
Have I told you recently how much I love you, man?
oh I would have just welded a standoff and used a ranger v6 idler puller to do it since they are generally smaller. them again I'm extremely lazy so yeah.
oh I would have just welded a standoff and used a ranger v6 idler puller to do it since they are generally smaller. them again I'm extremely lazy so yeah.
So, when I looked on eBay right after this... I found an 84 block-off plate.
I was going to use THAT as a guide for the bracket so that I wouldn't have to tear my bracket apart. And then it hit me... I will use THAT block-off plate as the bracket! It's easily 1/8th of an inch thick (if not thicker), and it's very, very strong. I saved all the original bolts for the block-off plate, which as you know, have studs on the ends of them so that you can attach that weird plastic thing where the harness passed through. I removed them and replaced them with normal screws simply because I didn't need the studs. But I'll put those back, and I can literally just mount the duplicate bracket onto that... cut the timing guide on it, drill a hole, weld a nut to the other end, and there I go... I've got my idler pulley!!!
I can then go back to the stock 87 belt, and continue to use the alternator as the tensioner.
Note, I started the car for the first time... just using starting fluid. Started right up, but no belt squealing. I don't think it's horrible, but so un-ideal. The slightest bit of rain, or some spirited driving, and I'm sure it would probably slip unless I go insane with it. And it's probably not good on the bearings to have a belt so ridiculously tensioned. When I have more coverage on the alternator pulley and the crank pulley... it won't need to be insanely tight.
Originally posted by 82-T/A [At Work]: So, when I looked on eBay right after this... I found an 84 block-off plate.
I was going to use THAT as a guide for the bracket so that I wouldn't have to tear my bracket apart. And then it hit me... I will use THAT block-off plate as the bracket! It's easily 1/8th of an inch thick (if not thicker), and it's very, very strong. I saved all the original bolts for the block-off plate, which as you know, have studs on the ends of them so that you can attach that weird plastic thing where the harness passed through. I removed them and replaced them with normal screws simply because I didn't need the studs. But I'll put those back, and I can literally just mount the duplicate bracket onto that... cut the timing guide on it, drill a hole, weld a nut to the other end, and there I go... I've got my idler pulley!!!
I can then go back to the stock 87 belt, and continue to use the alternator as the tensioner.
Note, I started the car for the first time... just using starting fluid. Started right up, but no belt squealing. I don't think it's horrible, but so un-ideal. The slightest bit of rain, or some spirited driving, and I'm sure it would probably slip unless I go insane with it. And it's probably not good on the bearings to have a belt so ridiculously tensioned. When I have more coverage on the alternator pulley and the crank pulley... it won't need to be insanely tight.
making good progress then. maybe I should make you help me with my internationals engine swap lol. your gonna have to make a parts list of what you used so we can replicate this in the future for more dukes especially since they tend to last longer with boost (compared to a 2.8)and the serpentine belt allows a supercharger to be easily mounted
[This message has been edited by cartercarbaficionado (edited 10-20-2024).]
What am I missing?
