WARNING on LADA Ignition Switches

[RRoller123]

Yes, or could be the white block connector just downstream of the ignition switch, maybe 10 inches or so. I think it is C34. I removed the housing and directly connected all the leads. Can also be the Brown and Red wires that are connected by a bullet connector each, right behind the Alternator. Also can be the connection to the solenoid on top of the starter, it is typically just a Faston. A weak battery will do the same thing too. Very frustrating, this entire system. Worst part of the car, by far.

[SteinOnkel]

Thanks for the information. I also have a LADA ignition switch installed few month ago. The car worked fine since then but i noticed these last days that sometimes when i turn the key from "RUN" to "START" nothing happen. I need to do it 2 or 3 times to have an ignition.

Is it the beginning of the ignition switch failure ?

Yes.

Do you have relays installed to take the load off of the ignition switch? If not, the Lada units will not handle the load for long and you will run into the issue described.

Also check the wire going to the starter solenoid. Mine was in piss poor condition, with no less than 6 home depot style crimp connections.

[SteinOnkel]

Pete, thanks for the heads-up on this issue. I've had a few instances where the starter didn't disengage once the engine fired, and I would describe it more of a "whhrrrrr" sound. Not good of course, but my sense is that it's not likely to do too much damage as long as the condition is momentary. When the starter does this, the solenoid is engaged longer than it was meant to be, which runs the risk of eventually burning out the windings. Or the contacts in your ignition switch due to the current flow.

The other issue is that, when the starter stays engaged while the engine is running, the starter motor itself is spinning much faster than it was designed to do, as it's being carried along for the ride. I sense that the cranking speed with just the starter motor is 100 to at most 200 rpm, so even when the engine is just idling and the starter motor is still engaged, the starter motor is spinning at least 4 or 5 times faster than it was designed to do. Not good for bearings and the like. And that "rushing" sound you heard (or "whhhrrrr" as I described it)? That's likely the sound of your starter motor shaft and armature spinning way faster than they should. Kind of a much larger version of those little D size battery-operated DC motors you might have played with as a kid.

Anyway, sounds like you have a path to a solution, and so my above input is just my thoughts rather than specific suggestions.

-Bryan

Just something by the by. When you install programmable ECUs, a required step is to tell the computer what your cranking speed is. This is easy to measure as you need a digital tachometer signal anyways.

I have been surprised almost ever time by just how fast the cranking speed is. On my 1.6 VW, it is 550rpm. On my brothers 914, it's about 500. Our Miata racecar is 600. And my buddy's e30 turbo is 450.

Cheers
Steiny

[18Fiatsandcounting]

Thanks, Steiny, although those cranking speeds seem awfully fast to me. I had always assumed that for a gas engine, a cranking speed of 100 to 200 rpm is fine, and somewhat more for a diesel (200 to 300 rpm). I suppose I could go out to my Fiat, crank the engine, and watch how many times the cam pulleys rotate in 5 seconds or so. The crankshaft would be double that speed, but it's hard to see the crank pulley when reaching through the window to turn the key to start. Let's just say my pulleys rotated 10 times in 5 seconds, which would mean the crank rotated 20 times. In one minute, that would be 240 rpm.

I also believe the gear reduction setup between the starter motor and the flywheel is around 20:1. In other words, if your starter motor cranks over at 4,000 rpm, your engine would turn over at 200 rpm. However, if your starter didn't disengage, and you revved that bad boy up to 4,000 rpm, your starter motor would be spinning at 80,000 rpm. Ouch...

-Bryan

[SteinOnkel]

The only way for you to accurately measure it is to install a vr or hall effect trigger wheel and sensor And then you're already halfway to a programmable efi

Diesels I'm not sure they crank faster. The only Diesel I own is a 7.3 and its cranking speed spec is 150 rpm minimum. You're not going to spin that 1000lb hunk of pig iron any faster.

[18Fiatsandcounting]

I think you just buy better batteries than I do!

[Rant/On]
Seems like it wasn't that long ago that a decent battery was $60 or $70 for a group size 24. Nowadays, they cost you $110 to $120 minimum for the El Cheapo style. And of course, me being the grandson of El Cheapo himself, I buy cheap batteries (read: not very strong).
[Rant/Off]

Hey, how about this for a poor man's Hall effect sensor for measuring cranking speed: Hook up your timing light to one of the plug wires. Crank the engine for 10 seconds, and count how many times it flashes. It should flash every 2 crankshaft revolutions, so if you see 20 flashes, that means 40 crankshaft rotations every 10 seconds. Or 240 rpm.

OK, I think I have derailed this thread enough already. Sorry....

-Bryan

[SteinOnkel]

Our school bus needs 5 new batteries. 2 are dedicated just for the starter, 3 for the fridge, lights, music. So I'm right there with you...

The cheapo hall won't be very accurate for two reasons. Firstly, it won't flash the moment you hit the starter, whereas a trigger wheel will start counting teeth immediately. Secondly, most (if not all) of my timing lights have been almost useless in diagnosing no-starts, because they take a good solid 5-6 seconds of cranking before they light up.

Yeah, what were we talking about again?