I looked at the online videos of how to change the serpentine belt. As usual, it looked so easy. And as often is the case when I try to work on a vehicle, nothing went right. I couldn't get the belt off, even after adjusting the tension bolt to the right so that the pulley shifted. So I took the nut off the tension pulley. I had pre-orderd my belt from Amazon, and picked the one they said fit my 2005 Prius. It didn't - way too big. So now I needed to put it back together with the old belt, so I can drive it to the auto parts store. I coudln't see very well to put the belt back on the water pump pulley, and couldn't get my hand down in there to feel it to see if it went on. Ended up having to jack the car up and crawl under to where I could get a view, but then coudln't really make it stay on the pulley from the underside. But I finally got that lined up and the flat side of the belt going up against the AC compressor pulley. Then when I went to try to put the tension pulley back on through the belt, I couldn't for the longest time get enough of the bolt through so that the nut to hold the pulley would grab the threads. I think I eventually pulled the pulley back out, and then tried one more time, and it engaged really easily! But then it wouldn't tighten up the big flat washer properly, and I realized that something was missing. Looked under the car, and sure enough, the other two-thickness washer-like thing was on the ground. So had to take it all apart again, and put that where I "thought" it went - on the bolt on the inside of the pulley. Finally got the pulley on and then went to turn the tension bolt to the left this time to tighten it back up. Nothing happened - everything just seemed to get looser, so then I turned it to the right and it snugged up a little. But the belt is still very loose - no matter how much I turn that bolt in either direction. I might have put the two-thickness washer thingy on incorrectly, but no one shows how that is supposed to go. Anyway, after working on this about 5 hours, I still don't think I can drive it with such a loose belt. Anyone have a suggestion?
Toyota’s parts catalog says the idler pulley (tension pulley) assembly is part number 16630-21020, for which there are several Google Image Search results that might give you an idea about how it goes together. A search for idler pulley on PriusChat also finds many possibly-relevant threads.
Also, I know it's water over the dam now, but for future reference, the belt is very inexpensive at my local Toyota dealership. Less than $15. IIRC, it was more like $12. Not sure what it's like in Albuquerque, since it's a smaller market. I've replaced two of them and my arm just fits in there.
It sounds like the op needs photos to show how the adjuster pieces fit together. Is it possible to post a couple of photos? IIRC your wife still has a Gen 2.
Could this be part of the issue? There's more than one thing weird in this description. Your profile says you have a Gen 2 (2005). That shouldn't have an A/C compressor pulley, it should have an electric A/C compressor with orange wires plugged into it. Even if you actually are talking about a Gen 1 (2001 to 2003) with the belt-driven A/C, the routing you describe would be backward. The A/C compressor has the V pulley that the belt goes around in the normal way (V side in). The water pump is what has the flat pulley driven by the back (flat) side of the belt. -Chap
parts.toyota.com says there is a cooler compressor.. Here is their 2005 Prius belt diagram. Perhaps the op confused that with the air conditioning compressor.
Wow ... might need to add a poll to the thread, figure out what percentage of people driving Gen 2 (2004 to 2009) Prii have belt-driven A/C compressors. Or somebody could report a catalog error to parts.toyota.com.... -Chap snark aside, the diagram shown above is a complete and correct one for Gen 1, 2001 to 2003. Japanese-to-English translation being an inexact science, Toyota has at times used "cooler" and "air conditioner" interchangeably.
No; electric water pump came with Gen 3—the first generation to have no serpentine belt at all. If parts.toyota.com has the wrong drawing up for Gen 2, it could be possible they've mislisted the part number also. Buying a Gen 1 belt by mistake for a Gen 2 would make it too long, and it would not be possible to tension it properly. Gen 1 owners can buy a Gen 2 belt, if the cooler compressor pulley seizes and they need to get around without it. -Chap
"Cooler" (クラー ) and "air con" (エアコン ) both refer to "air conditioner". In my experience, most Japanese people say "cooler". But my family's Panasonic Inverter unit says "air con". So, bad terminology on Toyota's catalog should be duly noted. Posted via the PriusChat mobile app.
Hi Chap and everyone who posted to this afterward. You're right, I'm such a non-mechanic that I didn't know that the main pulley at the bottom is the crank, which makes sense - something has to drive the other pulley. And I'm not even sure that my Prius is a generation 2, but I thought so. So now after everybody's help, I now know that the only thing the belt drives is the water pump. It turned out that although the old belt was too loose, it still spun the water pump pulley so that I could drive it to an auto repair facility, where I'm having them install the new belt. Part of the problem was that we are planning a road trip in the Prius on Wednesday and my next couple of days were pretty busy, so I figured it was worth the $100 to get the problem fixed by professionals.
Thanks so much, Elektroingeniur! That helped me to realize that I didn't lose any parts in the engine when everything came apart! See my reply to ChapmanF above.
Good advice, Jerry. I think that locally the Toyota Dealers charge about $27.00, but it would have been worth it to have the right one. See my reply to ChapmanF above. So it was getting the belt on the crank that I was having so much difficulty with. Your pictures didn't match the look of what's on my vehicle. I don't have super fat arms, but mine sure don't fit down there in between everythig else.
Thanks for your efforts, Prodigyplace. This diagram doesn't match my vehicle. The "CC" pulley isn't there.
If you do, indeed have a 2005, then you have the exact same belt arrangement as my wife's 2007 that I photographed. And it is a Gen 2. If it's older than 2004, then it's a Gen 1 and uses the different pulley setup mentioned above. If it's newer than 2009, then it's Gen 3 and doesn't have a serpentine belt. You are correct that the diagram that Prodigy place found is incorrect. Here are two inks to videos for changing the belt. The first one is the way you do it if you can't get your arm down in there. The second is more like I do it. IIRC, the guy in the 1st video had the directions backwards for turning the tensioner screw. Video #2 is much more professionally done. And a picture from video #2 showing the correct route, which is pretty simple.
Sorry, I was trusting Toyota here. V-BELT. For 2005 Toyota Prius HYBRID | Toyota What good is a free parts lookup if it is wrong?? It was @Elektroingenieur that mentioned parts.toyota.com .
Indeed. As I understand it, parts.toyota.com is built by SimplePart by converting Toyota’s own Electronic Parts Catalog data. Perhaps Toyota noticed how many third-party sites do this and decided to get in on the action. I think the error may be only in the illustration, not in the part number for the belt (90916-02570), which is the same as the one listed for the second-generation Prius (NHW20) in the 2010 edition of Toyota’s Fast Moving Parts Catalog book.
I did investigate that area on my 2005, in 2005 and concluded that everything was fine. I seem to remember taking the tension off the belt and then noticing that one of the pulleys was actually 2 half pulleys and thought maybe I should return everything back to normal. So I did. Water seepage from that Gen 2 water pump was considered normal at that time. I had a bit of seepage than concerned me, but could not tighten the nuts any tighter and decided not to use a cheater bar, that can be disastrous. My belt, about a year old was fine. Never had any troubles in that area. I worked totally from above but did jack up the right front corner to see if access could be improved, but access was worse from underneath. Sorry I couldn’t help with your present problem, but you see that others have also struggled in that area. From one Diy to another Diy.