is my crank pulley bad?

#1 02-05-2006, 09:48 PM

I suspected that my woodruff key and crank pulley have been causing my car troubles lately, so I decided to take them off and inspect. Can you guys look at this picture and tell me if the pulley has been worn and needs to be replaced? I have pictures from other angles, too, if they would help. Thanks!

svxfiles · #2 02-05-2006, 11:02 PM

Yep, it's bad.
Show us a picture of the crankshaft.
I hope it's ONLY the pulley and key.

NikFu S. · #3 02-05-2006, 11:07 PM

Looks like you caught it fairly early, relative to my experience. Get a new pulley and key, and make sure it's torqued down with a torque wrench.
Take pics so that if it happens again you aren't accused of improperly torqueing it.

I doubt your crankshaft is hurt at all. If it is, man are you out of luck.

AppStateSVX · #4 02-05-2006, 11:32 PM

yep, looks like another SVX crank pulley has bit the dust. Contact Dayle for a cheaper replacement, I have one and it works great

svxcuseme · #5 02-06-2006, 06:23 AM

Guys, how can you tell the pulley is bad from the pics?

angmercy,

What were the symtoms that led you toward the pulley?

#6 02-06-2006, 07:06 AM

svxcuse me,

Initially I had no idea what the problem was. My gas mileage decreased dramatically (at least 50% decrease) and the car severely hesitated. When the car was cold it wouldn't go over 20mph, ~1500rpm, but ran fine once it warmed up. We did a little tune up on it since that hadn't been done in a while, and replacing the spark plugs seemed to help for a week or so, and maybe all that wasn't related to the crank issue, I don't know. But what really made me realize the problem was when the car started vibrating a lot. It was almost like getting a massage while driving down the road. The power steering belt broke, and when we went to replace it we realized that the bolt holding on the crank pulley was loose. Then all the pieces started to come together, also from my knowledge of the Miata, because this happens to some of the early ones. I found some old posts on this forum which also helped figure it out. It took a little while and I was about to give up and take it to a mechanic when I finally realized what it might be and took off the pulley. Thanks to everyone here who has posted in past threads about this and replied to me.

dcarrb · #7 02-06-2006, 07:54 AM

Quote:

Originally Posted by angmercy

svxcuse me,

Initially I had no idea what the problem was. My gas mileage decreased dramatically (at least 50% decrease) and the car severely hesitated. When the car was cold it wouldn't go over 20mph, ~1500rpm, but ran fine once it warmed up. We did a little tune up on it since that hadn't been done in a while, and replacing the spark plugs seemed to help for a week or so, and maybe all that wasn't related to the crank issue, I don't know.

All the crank pulley does is drive the accessory belts, so be aware that something else must have been causing your fuel consumption/hesitation troubles.

dcb

oab_au · #8 02-06-2006, 03:36 PM

Quote:

Originally Posted by dcarrb

All the crank pulley does is drive the accessory belts, so be aware that something else must have been causing your fuel consumption/hesitation troubles.

dcb

Not only, but also.

The one key way locates the pulley and the crank sprocket to the crankshaft. The pulley bolt clamps the two to the crank. If the bolt is loose the pulley and sprocket can move on the crank to develop backlash. On the back of the crank sprocket is the crank sensor, so when there is enough backlash, the cam timing, the ignition timing and the injector timing, are all retarded.

Harvey.

dcarrb · #9 02-07-2006, 08:11 AM

Harvey,

I continue to be impressed by your know-how. Would crank sensor-induced troubles improve as the car warmed-up, as angmercy posted?

dcb

SomethingElse · #10 02-07-2006, 08:41 AM

When my crank pulley went bad it chewed up the middle cover for the timing belt. This cuased small plastic chunks to get in beetween my gears/ belt and jump time. I highly suggest pulling your covers off and check all of your timing marks..

want-a-fast-svx · #11 02-07-2006, 08:56 AM

so would crank walk be causing my horrible low end power delivery and idle problems along with my bypass air solenoid code? SOrry to get slightly off track but i need to figure this out and dont want to by solenoid for no reason. If anyone knows where the main relay is that would be greatly appreciated info...

SomethingElse · #12 02-07-2006, 09:33 AM

can you post a picture of your crank?check your base timing,look in the how to documnets section, I think there are more details there. I would do the free stuff first b4 I start throwing parts at it.

svxcuseme · #13 02-07-2006, 09:37 AM

I took my intake off a couple days ago. Forgot to tighten the ground wire on backside intake and got this code as well as horrible running condition. Check your ground.

Also, when you put the ECU in D-Check mode, one blue wire inserted into connector pin 1, you can here the bypass air solenoid cycle on and off, clicking sound. If you open the hood and can't here it, passenger side, back corner of intake, and your ground is good, you may have a bad solenoid.

want-a-fast-svx · #14 02-07-2006, 10:54 AM

alrighty i just checked the pin in dcheck mode and i can definitely hear two different clicks going on and the ground definitley looks good. I;ll pull it off and sand the contacts down along with the back of the manifold but it def. looks to be a good ground. So if its got a good ground and its clicking what direction does that put me in? More than likely a wire problem or the solenoid? I definitely appreciate the help i;ve been battling this for quite some time. I could check the wiring i just dont know where the main relay is to check the resistance voltage at that the manual keeps referring to. Connetor b52 i believe dont have the manual in the house with me.

svxcuseme · #15 02-07-2006, 12:52 PM

yes sounds like the ground is good and solenoid is working, at least it's getting a signal from the ECU. I'd look for possible vacuum leaks, around this valve or otherwise. I scanned in the troubleshooting chart from the 92 corrections manual for the bypass solenoid and put it in my locker, in case you don't have the voltage specs. Hopefully this will help.

The large wire connector the instructions reference is one of the yellow plugs going into the ECU under the dash. Count the number of wires to make sure you have the right connector.