Toyota Will Drive Me Nuts! Ac Idler Pulley And Belt

[zero]

I posted earlier about my AC belt being too loose. Toyota adjuster gives very little adjustment. I've tried all the betls listed for a Toyota 22RE with AC, idler and NO air-pump. Another person posted about having success by getting a special sized belt at O'Rielly's. I have not has the same success - yet. No O'Rielly's here but they just sell Gates belts anyway.

Problem # 1 is the belt idler pulley. Bearing starting to dry up so I ordered a new bearing (from a Toyota dealer). Totally wrong. Not even close. So I then decided to just use the bearing ID # and buy generic. The OEM pulley has a NTN bearing, # 6203LU. I went to Autozone and ended up buying a complete new pulley (instead of just the bearing) since their pulley had a bearing in it with the exact same number. Got home and no-good. Same number; different bore size. So now I either have to search the planet for a bearing somewhere that was like the original Toyota used in my 1988 22RE, or maybe get a new mounting bolt to match the new, "wrong-bore" pulley. Note - I checked Gates total catalog for idler pulleys and they do not sell one like the original. In fact, Gates sells no pulleys with an 18mm mounting bore.

The OEM pulley is 3 1/4" diameter, 1/2" single V-groove, and has a 18.3 bore mounting hole. The Gates (or NAPA, or Autozone, or Advance) will come up with a pulley that is 3 1/4" diameter, 1/2" singe V-groove, and a 12 mm mounting hole.

The stepped mounting bolt that Toyota uses has a raised 18 mm diamter mounting area, but the threads are 10 mm X 1.5. So maybe I can find a new standard 10 mm bolt and slop on a new idler (10 mm is kind of sloppy in a 12 mm hole).

Or I can search the world for a new bearing like Toyota originally used. It needs to be 17 mm X 40 mm X 18.3 mm. I DID find one over in some third-world country labeled as a "203FF" instead of a 6203.

Back to the belts. The Gates 9370 (1/2" belt by 36 degrees) might of fit at one time and stretched a little. The new size is given as 37.1" and when I measure it on my belt gauge, it shows as 37.25". The next size smaller is a Gates 9365 with is 36.5" (Orielly's calls it 36 7/8". I was able to get the belt on with the idler pulley off, but it's too small to get the pulley back on. Very little lee-way here. I then tried a 36 7/8" belt that was thinner (15/32") and it was too sloppy.

I don't think I've ever had such a hard time getting parts for a vehicle that was sold in the USA. And - I'm an 80 mile round-trip to the nearest auto-parts stores.

[jjrbus]

I am not having any luck with a simple little thing like lug nuts and I am just a couple minutes from several chain auto parts stores. Would you like fries with that part sir?

A long time ago in a land far away (NY) I would have shopped around for a bushing for the 10mm bolt or even had one made. Now because nobody makes anything or stocks anything I have to turn to the internet. There is a big selection online, that might be of use.

Then of course the sane thing to do would be to sell the Toy and buy a set of club's, but I do not really like golf.

Jim

[Back East Don]

For bearings I avoid autopart stores and just take the bearing directly to a shop that specializes in bearings. I've owned some pretty strange stuff over the years. 1959 Cat D6, 70's John Deere skid steer and a few odd ball tractors with all sorts of attachments. So I've needed all sorts of oddball stuff that equipment dealers no longer offer or are just too expensive not to source somewhere else.

A quick question/comment regarding the adjuster range. When I got my 87, I went through the belts and hoses and such. When I went to replace the belts, when I went to loosen the adjuster, the long bolt broke at the end. I pulled it all apart and was able to use some heat and a pair of vice grips to back it out the other way. I filed the bolt and reused it even though it was short till I was able to replace it. I don't know what the V6 looks like the the 22RE seems to have a decent amount of travel (at least with a long bolt). Just an idea as I figure you'd be on top of this more than I.

As to odd ball stuff, that is why I keep my shop stuff even though I am totally out of room. Still I'd rather buy than fabricate.

[fred heath]

Could you drill and tap the receiving hole for 12 x 1.5 ? Then use a straight 12mm bolt.?

[Maineah]

A 6203 bearing is about as common as it gets for a small bearing any thing from idler pulleys to drive end bearings for alternators they all should be 17X40X12 MM only difference I know of is the seals. I'm pretty sure I have one in the tool box I'll measure it.

[zero]

Yes, drilling and tapping for a straight bolt ought to work. Ends

Up the original threads are 11mm x 1.25. That is an off ball. If I drilled and tapped to 12mm, seems it would work. As to bearings and auto parts stores, their bearing number spec charts show the same as mine. I been in the business of scrounging parts for years work cat all is cjaets john forgot you need for all etc. By the way , i, on an android mini and not my computer, so please excuse all the typos. What perplexes me the most is having two bearings with the exact same numbers bit with different sizes. Ends up after I did a search for bearings with 18mm bores, I found the national 203ff to be the correct bearing and advance auto had it in stock for seven bucks

So ... The 203ff is the replacement for the original 6203ru bearing

is

[Maineah]

Yep found one 17X40X12. They do make some roller type 6203's but they are the same size and even some with snap ring groves.

[Maineah]

The early AC were all aftermarket so I guess who every made any particular one could have used a different bearing.

[zero]

About the threaded adjuster range. There is none for the ac. Only the power steering has a threaded adjuster. adjustment

Ac just has an idler on a swing arm with a small range

[fred heath]

The thread pitch on my engine seems to be 1.25 for all the bolts I've had to replace. Mostly 10mm and 8mm.

If its an arm type of hookup, maybe drill straight through and use a nut and lock washer.

[fred heath]

Second thought. Not sure what your setup is, but can you extend the adjuster slot to compensate for the larger belt.?

[WME]

A 6203 is a standard bearing 40mm OD x 12mm W x 17mm ID. $5-6 ea.

[Bob C]

When I was working on mine, I found that 36 7/8" belt that worked. I was in the process of locating someone to make me a longer adjustment arm when I got that belt to work.

[donttreadonme]

Was looking through my Winnebago manual (huge 3 ring binder with data sheets for equipment) and see that my cab ac is some type of aftermarket one. Either my compressor is going bad or the belt is too loose. Squeals sometimes when under load.

1992 camper. Has anyone replaced the compressor? Is it normal to have a different sized belt other than what would have been on a regular Toyota 1-ton truck with ac? I see all of the posts above and it concerns me.

[zero]

A 6203 is a standard bearing 40mm OD x 12mm W x 17mm ID. $5-6 ea.

As I said previously, the 6203 bearing in my Toyota AC idler pulley has an 18.3 mm bore. Yes, 6203 is a common bearing number you can buy near anywhere. Problem is - it does NOT fit and has the wrong dimensions. I suspect what has happened is this (just a guess). Companies likes Gates that make and sell new pulleys spec them out by bearing ID# . For most bearings other then those with numbers that end in "03" that works and matching numbers insures matchings sizes. Bearings that end in '03" however, are exempt from that rule. That's what is says in my bearing interchange book. As I showed in the photos, the bearing in my original pulley, and the bearing in the new pulley have exact matching bearing numbers but have different bore sizes.

Here is the bearing that DOES fit. A National 203FF is the exact match for the original 6203RU in my Toyota. A new 6203RU bearing will NOT fit.

It almost seems Toyota was out to screw the common mechanic or parts seeker with this AC belt-tension setup. #1 - the bolt is 11 mm. Not 10 mm and not 12 mm. NOT very common. 11mm X 1.25 thread pitch. Also, the hex head of the bolt to tigthen the tensioner and lock it in place takes a 16 mm off-set wrench. Another odd-ball. When I was a kid back in the 50s and bought my first metric and also my first Whitworth wrench sets - that metric set not only came with all the sequential whole sizes, it also came with many half-sizes. I.e., 10 mm. 10.5 mm. 11 mm. 12 mm. 12. 5 mm. etc. Now adays? Many metric wrench sets no longer come with half sizes and also skip many whole sizes. Last set I looked at on the shelf had - 10 mm. 12 mm, 13 mm, 14 mm. 15 mm. 17 mm. 19 mm. and 21 mm. The 11 mm, 17 mm, 18 mm. and 20 mm sizes were left out.

The AC adjuster is just a short pivoting arm. No slot, no adjuster bolt. No way to get more range out of it unless someone built a longer arm. I tried five different belts last night and the only belt that worked was what was on there before. A Gates XL9370, or Autozone Duralast 17370. 37.1" long and 12" wide. The old 9370 was the one that was too loose and measures 37.25" on my belt gauge. The new one measures 37.1" and with the adjuster nearly at the end of adjustment - the belt tightens up fine. The next belt size smaller is called "36 7/8" and is too small to get on.

[Totem]

Just curious but what started this quest? was your existing bearing trashed? I ask this because my rig makes this random squeal and I have already replaced/tensioned the alternator belt to spec. The squeal sounds like belt squeal but doesn't seem to be coming from the alternator belt. That leaves only the compressor. Also the squeal is only at high (for a motorhome) speeds/rpms like 55 +. So now I am thinking my idler bearing is bad too... I have 87,000 miles on the odo.

[zero]

My AC was squealing whenever I turned it on. Also had some intermittent squeals with AC turned off. #1 squeal was from a loose belt and the adjuster was out as far as it would go. #2 "intermittent" squeals were from dried-out bearings on the AC idler/tensioner pulley and the power-steering tensioner pulley. On the latter (power steering) - none of the local auto parts stores even show a replacement bearing . Just the entire assembly for over $100. So I'm glad I did this at home with time on my hands. I took the PS idler off and it has a 6204 bearing; I bought one for $7 and installed it no problem. With the AC idler - as already discussed - the 6203 bearing was a problem since the new 6203 bearings are a different size.

As I assume many here already know, if the water-pump bearing is allowed to dry out, it can send the fan right through the radiator and wind up with a trashed radiator, blown head-gasket, etc. REALLY good thing to check - or just renew if suspect. A new water-pump is dirt cheap compared to what happens if allowed to go bad.

As a rule-of-thumb for me with any vehicle . . I check all the "non-system-lubed" bearings that will always dry out at a certain point and seize if not changed. On the engine - that includes the alternator, all belt idlers, air-conditioning pump clutch bearing, and water-pump. Usually easy to diagnose by just taking off the belts and spinning all by hand so see how smooth and tight they feel. Besides the engine on the Toyota RV, there is also the drive-shaft support bearing that ought to be checked and changed if needed before it dies out on the road somewhere. And also - for anyone with a 5 lug wheel, semi-floater rear axle - those wheel bearings are also "one time lubed" and need to be swapped now and then. Those are all the suspect "non system lubed" bearings I can think of.

I just had a intermittent squeal issue on our Dodge Grand Caravan with a 3.3 V6. I took off the serpentine belt and checked the idlers, etc. Felt dry and read to go. So I replaced all the idlers, plus the bearing in the AC clutch. Put it all together and it still made the squeal. Ends up it is a bearing in the alternator. Does it one and off. I was going to buy new bearings ($30, pretty high) and then spend a lot of time taking that Denso 150 amp alternator apart (NOT easy). Then I said the "heck with it." Got a brand new 150 amp Denso clone from China fo $95.

[WME]

A 6203 is not a 6203,weird. I seem to remember that I had a belt problem too. I seem to remember moving the idler "overcenter" to the other side and then found a belt that fit.

Of course my rememberer could be wrong