STARTING WOES - HELP!

[bldn10]

We've exhausted ourselves over on the Mazda forum so I'm throwing this out here. I don't think it is really a Mazda-specific issue.

2nd gen. ITS RX-7, new battery + 300 amp booster, new rebuilt starter, new plug wires, 2 events on engine rebuild

This car has always turned over slowly but now it won't turn fast enough to even fire up. To eliminate any issues w/ kill switch, ignition, cables, etc., I unhooked the battery cables and ran a new battery cable from the + post to the + lug on the starter. I jumped a ground from the battery neg. to the starter case and applied 12v to the solenoid terminal. It still turned over too slow to start. I pulled a plug from each rotor and it was a little quicker but still not fast enough. Thinking the clutch might be stuck, I jacked the rear off the ground, put in 5th, put the clutch in, and cranked it - wheels not turning. Just to be sure I took the starter off this morning and checked it and it spins fine. Any ideas? I am at my wit's end. :wacko:

[Conover]

Have you tried a different starter just in case? the windings could be shorted and it could be pulling too many amps. Got an inductive ammeter? you can see how many amps the starter is pulling, more than a few hundred and it's probably the starter. Otherwise I'd say it's got to be a wacked out apex seal.

[88YB1]

Sounds like a dragging starter. As the bearings in a starter wear they allow the armiture to go off center. This interupts the magnetic field location causing it to effect two sets of windings at once. Without going into all the terchnical jargon just get a new starter or have this one rebuilt.

Chuck
ITA pontiac Fiero

[ddewhurst]

Bill, I went back & read all the posts in the other thread. Following are some items/questions worth addressing. (I ain't getting into FI because I run a carb.)

A. HISTORY: I bought this car for the 2004 season. From the outset it turned slowly. From time to time it has been better and worse. In 4/05 I actually had the reverse problem - the pinion did not extend far enough! Bought a rebuilt starter at AutoZone and installed it but it did same thing. I widened the mounting hole a bit and it then worked. (Not using same tranny now.) The other day I replaced the AutoZone starter w/ one from my '89 parts car. So, 1 starter is a year and a half old and the other very old but w/ around 75,000 miles on it.

Key words, I widened the mounting hole a bit and it then worked. (Not using same tranny now.)

Is this part of the slow starter cause? Is the current bell housing the cause ? Do you have the original bell housing ?

B. When you connected the wires direct from the battery to the starter DID YOU MEASURE THE AMPERAGE DRAW? It don't matter if the starter motor & the car motor turned slow or fast you need to know what the amperage draw during an attempted start is. As you had previously said the friken starter/sol. gets HOT in a few seconds. If the starter/sol. gets hot in a few seconds with NORMAL starter amperage draw then the issue would seem to be electrical. If the starter amperage draw is not normal then the issue/issues could wellbe Item A., item C. or item D.

C. John W. questioned if the front pulley had been off with the motor in it's normal position by someone before you or have you had the pulley off ? The front e-shaft thrust needle bearing can slip forward & down screwing up the end play witrh the eccentric shaft thereby wedging the e-shaft making the starter do much more work than normal. You never answered the question John asked.

C. You talked about when trying to start the car it had no impact on rotational speed if the shift lever was in netural, if the clutch pedal was in or out. Do you have another bell housing around without the transmission input shaft ? If you do install the empty bell housing that will eliminate the connection of the input shaft to the e-shaft needle bearing/motor. I understand it's a different bell housing but it may narrow potential causes out. Or take your bell housing off the normal transmission & use it.

Bill, factual answers are required to item A., B., C. & D.

David is trying to support your effort. ;)

[bldn10]

I have tried 3 starters, one of which is a brand new rebuilt one.

A. I am not using the tranny/bellhousing referred to earlier. I originally was concerned that the starter pinion remained meshed w/ the flywheel but it was explained that it will do that until the flywheel turns on its own (engine has started). Indeed, all it takes is a slight manual turn of the flywheel w/ a screwdriver to release it. I do not think that is the issue.

B. David, how do I check the amp draw? What should it be? I have a multi-tester. What would excess draw indicate - a bad starter? I've tried 3.

C. The engine-builder has assured me that end play, etc, was done to spec. The engine has 2 events on it.

D. No, all I have is complete trannies - it is one piece. The engine turns easy enough manually that it is unlikely that the drivetrain is engaged.

A GT1 buddy just left and we tried everything we could think of, including jumping from his car w/ heavy duty cables. He got to his wit's end too.

[eprodrx7]

So Bill humor me and check the end play. Mistakes are made and this is an easy one to make. Short of that why not take the car to a competant Rotary mechanic?

[Daryl DeArman]

Followed the other thread for awhile. New thoughts....

Pull start the car. You've tried 3 starters w/o luck. None of them disengage because the flywheel doesn't turn faster than the start drive gear...it will if it starts. So, eliminate the starter from the list of probable causes and confirm the car will run.

If it runs, go back to the starter issues. If it won't run, the starter is probably fine and you've been chasing the wrong problem.

If that isn't possible--install one of the "suspect" starters in another rx7 and see if it starts.

[bldn10]

"So Bill humor me and check the end play. Mistakes are made and this is an easy one to make."

Sorry but I’m not pulling the transmission to humor anyone! :-) Especially when the guy who built the engine swears that end play was set at spec. And is that really likely to be the cause of slow cranking?

"Short of that why not take the car to a competant Rotary mechanic?"

Like I said, I don’t think this is really a [rotary]-specific problem. I’ve already spoken to several competent mechanics and they don’t know either. Everything has pretty much been done except an in-vehicle load test. How do I do that?

"Pull start the car. You've tried 3 starters w/o luck. None of them disengage because the flywheel doesn't turn faster than the start drive gear...it will if it starts. So, eliminate the starter from the list of probable causes and confirm the car will run. If it runs, go back to the starter issues. If it won't run, the starter is probably fine and you've been chasing the wrong problem."

Let’s solve one problem at a time. At the moment I’m not concerned whether the engine will start -
only that it will spin fast enough to start.

"If that isn't possible--install one of the "suspect" starters in another rx7 and see if it starts."

You know, I seem to have misplaced all my spare cars somewhere. :-) But I will try that next week on a buddy’s car when he gets back from the event I am missing as we speak. And I’ll see if his starter works in my car!

Just to be sure I re-charged the new battery. I did a voltage test and it only drops from 17 to 15 at the battery while (slow) cranking. Per Haynes that indicates a bad starter but I just cannot believe that.

Thanks for your help, guys.

[dj10]

Bill, have you checked your main ground?

[Daryl DeArman]

"Let’s solve one problem at a time. At the moment I’m not concerned whether the engine will start -
only that it will spin fast enough to start. [/b]

Bill, I understand the length of time that you've been dealing with this issue and the fact that you are missing an event as we speak is only adding to your frustration. I did see your smilies :)


I will try that next week on a buddy’s car when he gets back from the event I am missing as we speak. And I’ll see if his starter works in my car! [/b]

Chances are that you didn't get 3 bad starters in a row and that there is another problem. Verifying that the car will start puts you back into the starter circuit mode. If it doesn't start there may be a problem elsewhere that you will never solve looking to the starter circuit for an answer.

By installing your buddy's starter in your car you have one of two possible outcomes.

1) it starts and you are on the search for another starter that is the same as your buddy's

or

2) it doesn't start....you've learned nothing. You still don't know whether your starter is good. If your motor will run at all...or if you have another issue in the starter circuit. If you put your starter in your buddy's car and it starts right up you can at least eliminate one component as being suspect.

[bldn10]

"Bill, have you checked your main ground?"

"... I jumped a ground from the battery neg. to the starter case ..." That eliminates any possible issue w/ grounding. But, yes, I've checked it.

"By installing your buddy's starter in your car you have one of two possible outcomes.
1) it starts and you are on the search for another starter that is the same as your buddy's
or
2) it doesn't start....you've learned nothing. You still don't know whether your starter is good. If your motor will run at all...or if you have another issue in the starter circuit. If you put your starter in your buddy's car and it starts right up you can at least eliminate one component as being suspect."

Daryl, the test will not be to see if the car will start - only to see if it will spin the motor at sufficient speed to start. If I put his starter (which is known to work on his car) in mine and it spins it (and mine won't spin his), then I've learned that I have a problem w/ my starter whether or not the engine fires up. If mine works in his but his doesn't in mine then I know I have a mechanical problem and I will focus on that.

The fear I have is w/ my luck mine won't work in his and his won't work in mine!

Does anyone know how to do an in-vehicle load/amp draw test?

[Daryl DeArman]

You need an inductive ammeter with suffiecient capacity.

Something like this:

http://us.fluke.com/usen/products/LH1060+L...(FlukeProducts) (http://us.fluke.com/usen/products/LH1060+LH1050.htm?catalog_name=FlukeUnitedStates&Category=CLMP(FlukeProducts))