How do you replace the alternator in a 1986 Honda Prelude 2.0 si?

Answer 1

Tools needed: beer, patience, 14mm socket, 12mm box end wrench (ratcheting preferred); 12mm socket and ratchet; 10mm box end and socket; white paint marker pen; pb blaster (or wd40); nose pliers for hose clamps, courage.

1. Disconnect the battery negative terminal and move it out of the way so there is no possibility of it reconnecting inadvertently and showering you with spark!

2. Mark each of the vacuum hoses connected to the air cleaner housing and to the intake manifold - doing this will help immensely with getting everything back together correctly when memory fails! A white marker paint pen works wonders. Alternatively, the ubiquitous cell phone, to take digital pictures as a record of where everything fits, is a marvelous tool...different strokes..!

3. Carefully disconnect the two or three vacuum hoses going to the air cleaner housing (2), and about 4 connected to the driver side of the air intake manifold and move them out of the way; The idea is to get enough space to work on the alternator mounting bolts;

4. Undo the five quick release clamps (1 on top) from the air filter housing cover and remove the air-cleaner/filter and cover from near the firewall; there should be two clamps on the driver side and two on the passenger side. The inclination to "horse" things off means something is still connected.

5. Once the air filter and housing cover are removed, move to the passenger side fender and look down into the maw of the beast. At bottom right of the air filter housing base, there should be a quick release circular clamp securing an air intake hose (about 2.5 inches) to the air intake housing. Undo the clamp;

6. Next, to remove the air cleaner housing base -- remove the two stainless/chrome bolts and washers (the washers cover rubber grommets and can fall into the abyss and be lost forever, so be careful!) at the top of the housing -- there should be a ground wire connected from the firewall to the driver side housing bolt. Again, be sure to undo the quick release clamp from the bottom air pipe before trying to remove the air cleaner housing base - it is not obvious! Once the top two bolts are removed gently wiggle the air cleaner base off the back of the intake manifold; there are two rubber grommets in two plastic holders that keep the air housing base rattle-free and secure; wiggling it gently up and back toward the firewall will get it off...whew!!!

7. Locate the alternator mounting bracket - it is sort of triangular and is right above the water pump near the driver side fender; loosen the alternator tensioner nut (12mm) - it is on the longish bolt facing the firewall and is right near the water pump belt near the driver side firewall; using a 12mm box end wrench loosen the bolt that holds the alternator to the mounting bracket in front (engine side) of the tensioner bolt. This is a POS (read that piece of s***) bolt and takes forever to loosen because of the lack of space and inability to get a socket wrench in. If you have a 12mm ratcheting box end wrench, use it; will make it quicker, easier, and less of a b****!

8. After loosening the alternator mounting bolt and tensioner bolt, push the alternator toward the engine (toward the front of the engine bay) and slip off the drive belt from the pulley. If the alternator does not move forward, the lower mounting bolt is tight and will need to be loosened.

9. Fit a shallow 14mm socket onto a wrench, and feel around under the alternator mount for the second mounting bolt nut; place it on the nut and loosen the nut (counterclockwise direction). Loose now? Good! Don't remove the lower mounting bolt yet!

10. Using a 10mm socket, undo the bolt holding the two thick covered cable bunches attached to the intake manifold and put in a safe place; one of these wrapped cables comes from the driver side fender and the other from the top of the intake manifold; a bracket holds these two in place at the driver's side of the intake manifold. They only need to be moved a little bit, so don't' horse them around in any way -- bad karma!

11. Next, pivot the alternator back toward the firewall -- the loosened cables should now allow room to move the alternator out to where it is accessible! Using a 10mm socket undo the nut holding the wire at the top of the alternator and disconnect the wire. Now, reach under the alternator and pull out the long 2nd mounting bolt -- it has a large square head.

12. Now for the hardest part -- the main connector was a PITA, and only because I am filled with grace was I able to disconnect it without breaking it (or using very descriptive and highly colorful and imaginary language). This is the largish green plug with about four wires coming out of it. If the bottom mounting bolt is removed, the alternator can be twisted up so the back is clearly visible. The green plug has a thin plastic release bar that needs to be pressed down while pulling the plug out at the same time.