Advice on replacing a bad distributor

[Deathcricket]

So I noticed a funny sound, like a loose belt I thought. I popped the hood and a funny noise is coming from my distributor! Never replaced one and hoping to get some advise from the pros here. It's a 1990 6 cyl 3.0 EFI.

So first thing I did is dist pop the cap open, it was rusty and grimey inside and the "spinner" was badly corroded. I felt comfortable enough to replace the cap and "spinner" (prob not technical term) and then just to be safe I replaced the sparkplugs and wiring "while I was there". I noticed this was also pretty gross and the contacts were pretty worn, although when I got to the sparkplugs they were pretty clean with very little corrosion.

I just bought this car to take on some trails with 4wd. So I'm not sure the history or how well it has been maintained. After the little repairs I did the high pitched grinding noise still persists. I'm pretty sure it's coming from the gear section behind the cap. But before I plop down $240 I was hoping to get some advice on best how to troubleshoot this. Keep in mind I'm a car noob. But I'm very willing to get my hands dirty, I just don't to get in over my head and screw my car up worse than it is.

I watched a couple videos, couldn't find a 4runner specific one, but it looks like you pull the old one and pay carefull attention to the allignment of the back and just plop the new one in. Is it really that simple or am I asking for trouble getting into this? I also recorded the noise via video, it's a pretty specific noise and think that might help you pros to help me narrow this down.



Thank you in advance! Always get such good stuff from this forum.

 

[KidVermicious]

Nothing wrong with coming on here and asking questions, but that's something that's covered in the factory service manual or a haynes or chiltons or whatever. If you're planning on getting your hands dirty, you need to DL a factory service manual and get an aftermarket repair manual to supplement it.

Oh, and the spinny thing is called a rotor.

 

[Deathcricket]

Nothing wrong with coming on here and asking questions, but that's something that's covered in the factory service manual or a haynes or chiltons or whatever. If you're planning on getting your hands dirty, you need to DL a factory service manual and get an aftermarket repair manual to supplement it.

Oh, and the spinny thing is called a rotor.

RTFM noob!

Got it.

 

[Clone of the Mean]

If you do replace the distributor reference everything before you remove it!!! Take pictures, draw with a crayon, whatever. Look how the distributor is "clocked", look where the rotor is facing and make sure it goes back exactly the way it came out, and you'll be ok. If not you're going to have to find TDC and start all over again.

I watched my kid take his out for no reason, just did it. I thought his head was going to explode before I helped him out....

 

[Deathcricket]

If you do replace the distributor reference everything before you remove it!!! Take pictures, draw with a crayon, whatever. Look how the distributor is "clocked", look where the rotor is facing and make sure it goes back exactly the way it came out, and you'll be ok. If not you're going to have to find TDC and start all over again.

I watched my kid take his out for no reason, just did it. I thought his head was going to explode before I helped him out....

Thanks man! Gonna give it a try I think, have the new part on the way in a couple days. your advice seems to line up with pretty much everything I read.

In case anyone else is reading this in the future with a similar problem. Best RTFM I found is here. I probably should buy a book, but just too damn cheap. :high5:

Distributors | How to Replace

Disconnect the distributor cap from the distributor. The cap may be held in place with clamps that can be removed by hand, or you may need some basic hand tools. For example, some caps are held in place with screws. Note that many older GM vehicles have a screw fastener that only requires a quarter turn of the screwdriver to release the cap.

Disconnect the Distributor Cap

Make a diagram of where all of the electrical wires are located, and mark the wires using masking tape so that you can replace them in the same location on the new distributor.

Remove all electrical wires that are attached to the distributor.



Before removing the old distributor, you will need to scribe two marks which will help you install the new distributor with the same orientation. One mark should be made to match the distributor housing (outside body) to the engine mounting point. Pick a point on the outside of the distributor housing that is accessible and that you can reproduce (in the same spot) on the new distributor. The second mark should be made on the inside of the distributor housing to indicate the position of the rotor within the distributor. Think of the rotor as the hour hand of a clock. The rotor on the new distributor will need to be in the same position when you install it. This is important, since if you do not mark these points properly, you probably will not be able to start the engine with the new distributor installed.

Mark the Old and New Distributor

Take the new distributor out of the box and mark the outside housing in the same place as on the old distributor. In addition, try to orient the rotor in the same position. In addition, take a good look at the housing and shaft components that will not be visible when the distributor is in place. Note that the distributor shaft is rotated via a gear or slot at the end of the shaft. You will need to install this shaft aligned in the exact same way as the old unit. A little time and patience now will make things much easier when you go to start the engine!

Remove the bolts or screws that hold the distributor housing to the engine. Now gently pull the distributor housing out of the engine. Look carefully at the rotor, since its position may rotate as you pull the distributor out. This is normal. If the rotor arm rotates slightly while you are pulling out the old distributor, note the final position of the rotor, and use it as your starting point when you install the new distributor. In other words, the installed distributor must place the rotor in the same location as you marked in Step 4. Be as precise as possible with this.


Rotor of New Distributor Must Match Placement of the One That's Removed

Transfer your marks from the old unit to the new replacement distributor. Install the new distributor on the engine making sure that the distributor rotor and housing are in the same location as the old unit.

Re-install the fasteners that hold the distributor to the engine. Do not fully tighten these yet, but rather snug them down until you cannot rotate the distributor, and then loosen them just enough so you can rotate the distributor by hand with a little bit of effort. Again, make sure that all the marks are re-aligned (or if specific instructions are supplied with the new distributor, follow them).



Re-connect all of the electrical wires as noted in your diagram, and replace the distributor cap and spark plug wires.

Reconnect the Wires

Now comes the proof of the pudding! Double-check all the connections and start the engine. If the engine will not start, but sounds like it wants to, rotate the distributor away from your mark a small amount (just the width of your mark), and try to start the engine again. If it seems to have a harder time starting, rotate the distributor in the opposite direction, again slightly past the original mark. If the engine sounds like it wants to start but still will not catch, continue slight rotations of the distributor until the engine starts and runs.

Once the engine is running, let it warm up enough that it will idle smoothly. Then stop the engine and put a timing light on the No. 1 spark plug. Restart the engine.

Use the timing light, and following the instructions that are specific to your vehicle, set the timing. You adjust the timing mark by rotating the distributor housing by very small amounts. When you have adjusted the timing to the correct mark, tighten the distributor clamp fasteners.

Take the vehicle out for a test drive. Make note of the vehicle's response under acceleration and varying engine loads. You may be pleasantly surprised at the improvement.

 

[Clone of the Mean]

It really isnt hard to do but if it isnt lined up just right you're timing is shot and you have to find TDC all over again. Just put the new in exactly the way the old one came out. And mark your plug wires 1-6 and put them back exactly as well. Good Luck, keep us updated...

 

[Deathcricket]

It really isnt hard to do but if it isnt lined up just right you're timing is shot and you have to find TDC all over again. Just put the new in exactly the way the old one came out. And mark your plug wires 1-6 and put them back exactly as well. Good Luck, keep us updated...

Thanks man!

Got the new one in the mail today, whole proc took less than half hour, LOL. Like you said, I just marked all the plugs with a sharpee, marked where the rotor was aand made absolutely sure the gears lined up in the same spot while putting the new one in. Piece of cake, and really appreciate the advice. Can't believe I was going to pay a mechanic $500 and was so nervous about it. Whew!

 

[Clone of the Mean]

Glad it worked out!

 

[SV_Dude]

So is the noise gone?

Check out the old distributor and see if you can find exactly where the noise was coming from. Bad bearing inside the distributor housing?

I wouldn't have guessed that the noise was coming from the distributor. I would have guessed some external engine component like a pulley bearing or something.

 

[Deathcricket]

Yeah exactly! The old one is really hard to manually crank and it just grinds. Noise comes from under that big threaded gear you see under the rotor. My guess would be the seal on the bearings failed and they are dry and pulverized?

Just glad it was such an easy fix.

 

[RiFF RaFF]

Yeah exactly! The old one is really hard to manually crank and it just grinds. Noise comes from under that big threaded gear you see under the rotor. My guess would be the seal on the bearings failed and they are dry and pulverized?

Just glad it was such an easy fix.

Getting ready to do the same thing in a few minutes. Glad this has been written up. Gives me the confidence to go forward. Honestly I've never had to replace a distributor before. I'll take and post before and after pictures in my build thread.

Wish me luck ya'll.

:scared:

 

[dbd6604]

Wish me luck ya'll.

Luck ya'll!

 

[RiFF RaFF]

The operation is complete, and a success!

As soon as the pictures upload I'll post some pictures on my build thread.

Thanks for the mojo guys.

hoto: