pulley replacement

[Bubba]

1991

Inner belt pulley on engine has detached from main engine shaft. (The inner lining of pulley is destroyed and the pulley is dangling on the shaft). The belt for this pulley drives the alternator and air cond. How do I remove and replace this pulley.

[spiffyguido]

Can you clarify: "detached from main engine shaft". Do you mean that the pulley surface broke free from the shaft, or it spins freely on the shaft? I've never heard of this happening.

At any rate, swapping in a new one isn't hard. The main pulley bolt will be your biggest challenge. Start by loosening the tension off the belts. With that done, remove the driver's side wheel and pop the pulley bolt access port cover out of the fender guard. Behind it you'll see the pulley bolt.

The pulley bolt will likely be seized. 90% of the time these are hard to remove if they haven't been done recently. You can try with a standard ratchet first, but my experience shows that an impact wrench is almost always needed. A few shots of an impact wrench should spin the bolt right out. At that point, the pulley will come off without issue. Be sure not to lose the woodruff key that aligns the pulley.

[Bubba]

I have never seen this happen before. The pulley has broken free from the shaft with the inner lining or inner portion of the pulley destroyed. The outer portion of the pulley is free to rotate on the shaft. This portion is about one inch thick with an overall outer diameter of approx 8 inches. So I basically have a 6 inch hole in the pulley.

To remove the pulley, I must first remove the drivers side tire, then using an impact wrench with a 19mm socket, I should be able to remove the pulley. Since there are two pulleys on the shaft, I assume they both will come off once the pulley bolt is removed.

[spiffyguido]

The two pulleys are one piece, at least on the OEM setup. Do you have an aftermarket pulley setup?

I'd love to see pictures of this.

[Bubba]

I'll try to get some pictures.

Re: aftermarket pulley setup. Not sure what you mean but assume I will need to buy a replacement pulley. I intend to go to a Honda dealer and order the part. Will I need a special pulley puller to remove what's left of the pulley on the shaft? Also, when I have tried to remove the pulley bolt (assume normal threads CCW removal), it appears that the engine turns. I have a standard shift. How do I lock the engine from turning? BTW when the pulley broke the belts came lose and I have removed them.

[spiffyguido]

You can have a friend jam a screwdriver against the cogs on the flywheel to lock up the engine. This (sometimes) will generate sufficient resistance to break the bolt free. This is another place where the impact wrench is useful because they don't put sustain loads on bolts (just quick violent taps) so the engine won't spin.

You don't need a puller to remove the pulley. Honda uses a woodruff key setup to keep their pulleys in place. It should come right off. At least that's been my experience.

What I was asking about your pulley setup is whether it wasn't a pulley set from the factory but an aftermarket setup that somebody had installed since the car was new. I've never heard of the main pulley being two pieces, always one with two belt tracks.

[Bubba]

I have tried removing the bolt with an impact wrench but have not been successful. Just to be sure - which way loosens the bolt: clockwise (left hand threads) or counterclockwise (right hand threads)?

WRT pulley setup: I have owned the car since 1992 so I'm pretty sure the pulley is original equipment. Any suggestions on where to order a replacement pulley other than a Honda dealer?

Thanks

[spiffyguido]

http://www.hondaautomotiveparts.com" rel="nofollow" target="_blank is a good place to get a replacement.

The pulley bolt isn't a special bolt. You loosen it turning it counterclockwise.

Is your Prelude from the US market?

If your impact wrench hasn't worked, you can try to help the situation a bit by putting some heat on the bolt to try and break the seize. A propane torch can help because it is hot enough to cause expansion but not hot enough to melt the main engine seal really quickly. Try putting a little heat on it, and give it an overnight treatment if WD-40.

You can also try using a breaker bar, but this can be difficult as well. It's important not to load up the bolt too much and cause it to sheer off. Plus, with the breaker bar it gets harder to keep the engine from turning. Honda does make a hex socket that can be put into the hex pattern on the pulley itself (in some cases, not all pulleys have this) to clock the pulley in place.

If you really can't get it, try taking it to a local garage that has a professional quality impact wrench and ask them to quickly break the seize for you. These bolts are really tight, reportedly up to 180 ft/lbs from the factory, so if you have a low-grade impact wrench it won't have the power to break the seize.


Be patient. A quick search of this forum will show you that many people have had this problem. I had the same problem when I removed my pulley bolt to do my timing belt. I didn't have luck with a breaker bar (was basically lifting the car and no result). It wasn't until I borrowed a friend's air-powered MAC Tools impact wrench (a professional grade unit) that I got it off.

[Bubba]

Car originally sold in Biloxi, MS.

Appreciate all comments: Will try again this morning to remove bolt. If not successful, will get a professional grade impact wrench.

BTW I had the timing belt and water pump replaced in Jan 06 (103K mi). I now have 131K mi. Should I replace the timing belt?

[spiffyguido]

Since you're going to have the pulley off anyway, it wouldn't hurt. The mileage alone would suggest that you've got about another 20K miles of life in the belt, but when you compound it with the time (Jan 06 until now), the belt would probably benefit from a change. Water pump should be fine. If you didn't do the timing belt tensioner last time, I'd do it for sure.

[Bubba]

Looked all over the honda parts web site you suggested and couldn't find the pulley replacement. Any help in finding the part is appreciated.

[spiffyguido]

#13 on the illustration:

http://www.hondaautomotiveparts.com/aut ... CRANKSHAFT

[Bubba]

Thanks so much. Looked there but didn't recognize the part. I'm old and slow.

[Bubba]

Finally got the crankshaft bolt removed - very difficult. Now I need to replace the timing belt and tensioner. I need some guidance to do this. The diagram says not to remove the adjust bolt but I see no way to replace the tensioner without removing the bolt. Also, I know the alignment of the crankshaft and camshaft must be exact. So I intend to remove the tensioner spring first and then remove the adjust bolt and tensioner. The belt should slide off then and install the new belt and then install the new tensioner, spring, and then torque bolt to 31 ft-lbs. Please advise if this will work and any other comments.

Thanks, Bubba

[spiffyguido]

The directions in the service manual make the assumption that you won't be replacing the tensioner, that's why it only directs you to loosen it. Since you are replacing the tensioner (which is a really good idea) I think you have the right idea. Take everything off, and yes, you will have to completely remove the adjust bolt to get the tensioner off.

Assembly is where you have to be careful. For the sake of getting the belt all lined up well, I would actually suggest putting the tensioner back on before you replace the belt. This will help you get the teeth lined up. Just follow the markings on the cam pulleys and make sure your engine is rotated to TDC (mark on the flywheel). It's actually easier than it sounds to get it right. Just check, and then check again. Once the belt is on, then you can proceed with the 'Tension Adjustment' steps found on page 5-23 of the 1988 service manual. Basically you just have to check the torque on the tensioner a few times and manually rotate the engine a few revolutions to see that everything is playing nicely together. You'll know at this point if you got it right. If you rotate the engine a few times and find that your TDC mark isn't lined up at the same time as your cam pulleys have their tick marks equal to the head deck, you've misaligned the belt and need to start over.

Be ABSOLUTELY certain that you torque the tensioner correctly. Too tight and YOU WILL shred your belt. I've seen this happen, and it can happen quickly. Use a torque wrench, set it to 31 lb-ft and dial it right in. The torque on the adjust bolt doesn't just hold the tensioner on, it also controls the ability of the tensioner to function. Too tight, and the tensioner will seize and shred the belt. Make sure you put the spring back on. Gently check the tensioner adjust bolt torque both before and after you've rotated the engine a few times. The service manual also suggests making sure that the pulley bolt doesn't come loose in the process.

Does the tensioner come with a new spring? I'd think it a good idea to replace those as well.