Starter Dragging
 

So I've developed a new problem since installing a Sniper EFI -- the starter drags when the engine is hot. This never happened with the QJ. What could have changed? Extra current draw somewhere.

I've tried the usual fixes --heat shield on the headers by the starter, checked the starter cable and battery connections etc etc.

Thoughts?

Are you controlling the timing with the Sniper? If so can you retard it at cranking speed?

No, HEI.

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What do you mean by "drags"?

Doesn't disengage from the flywheel--grinds when you release the key?
Cranks slowly?
Something else?

What kind of starter? 10MT, non-GM mini-starter, GM PMGR?

How is it wired? OEM wiring? Solenoid-on-the-fender?

Barely turns, or not at all. Stock rebuilt starter and new stock engine harness for HEI.

Again, never did this with the carb. Something new with the EFI. System relay is wired to ignition at fuse panel under dash, and the main power lead is run directly to the battery.

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How is the the starter wired?


Battery cable to starter?
Ignition Start switch wire to the starter solenoid?


:confused:

Yes

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First Guess: It's a starter problem, not a FI problem.

Diagnose it like any other starter/battery/charging problem.

yes it sounds like a starter prob but i would try disconnecting the HEI next time you have this prob and just see if it cranks better

Maybe ignition switch...check the wires coming out to make sure your getting 12v...out...to starter..before replacing the starter

As stated above, when you check for 12 volts on the solenoid wire , check when you turn the key with the wire loose and hooked up to the solenoid. I have 12 volts when the wire is not hooked up and 5.7 volts attached to the solenoid when I turn the key. When I bring 12 volts to the solenoid from a different wire ( not the factory wire ) the starter works fine.

Check with a known good battery too

Low voltage/high resistance on the wire to the "S" terminal can cause "No cranking". It won't cause "Slow cranking".

Use to have problem on my 421 back in late 60s,starter bushings wearing egged.Bought necessary tools and bushings,replace them now.

All good suggestions. Remember that the condition is only when the engine is HOT and then been standing a couple of minutes. If I cool it off for 15-20 minutes away she goes.. Sounds like standard starter heat soak. My starter guy (who sold it to me rebuilt, that's his Business) says the starter itself tests out 100%.

So, must be the heat. Millions of guys have headers next to their starter and make out fine, so why is this one acting up ... ONLY since installing EFI? Makes no sense.

I'm thinking of changing to RARE manifolds anyways for ground clearance, but I ran across a set of Tribal Tubes locally and was considering them. LOVE the sound of headers! However, don't want to bite that bullet only to find that header-caused heat soak is the issue.

Sure. Sounds like standard heat soak to me, too. Did he "test out" the starter at elevated temperature? I bet "no". I would put a starting/charging system analyzer on that vehicle when cold, measure the starter amperage draw along with battery voltage while cranking. Then drive the thing so that it's fully-warm and would tend to act heat-soaked and slow-cranking. Connect the gauge, measure the amperage and voltage hot. Compare the two readings.

More-precise control of fueling (and ignition timing???) makes for better combustion, less misfire or excess fuel that might cool the combustion.. Better combustion makes for hotter exhaust? Hotter exhaust brings out heat-soak problems in the starter?

You're better off to treat it as a starting-system problem and not a fuel-injection problem. Don't get carried away, or blinded to what is actually happening. Diagnose this as a starting issue, solve it, and move on. Even if the FI has something to do with the heat soak--and I'm not saying it does--the starter must have been right on the edge of heat soak before the FI.

So even if you "fix" the heat-soak problem by, let's say, advancing the timing five degrees or adding additional fuel to the FI programming which might cool the exhaust a little, you still need to do something with the starter to shield it from the heat, so that the fuel and ignition can return to their optimum values. (assumes that the fuel and ignition are at or near optimum values now)

Is your electric fans coming on when trying to start? If so you could be losing voltage if they are running while it is cranking. Especially if dual fans running on just 1 relay. The fix is to close the relay in run mode but not start mode.

Does the engine run hotter with the EFI than it did with the Q-Jet, if yes that would explain why it is harder to start now than with the Carb as higher temps require more cranking power. If there were no changes to ignition timing then it sounds like it may be running a tad hotter with your EFI. If this is the case there are a few things that can be done to improve the starter system. You can install larger size battery cables, install a ford style starter solenoid, and/or a gear reduction mini starter. Make sure your ground wire is large enough and has a good connection. I run one ground from the battery to the frame and another from the frame to the engine using size 01 welding cable. I also use 01 welding cable on the positive battery cable to the ford style solenoid then wire from the solenoid to the starter and jump the start wire on the starter solenoid to the main cable.

Doesn't run any hotter, same T-stat and electric fan with turn-on at 195. I'll have a look at those wire sizes.

Hm. Good one, I'll have to check that.

OK so Spring has sprung and (self) checked all suggestions above and still no start when hot. Headers are changed and wrapped and heat shielded and the starter is cool enough to touch when no-start condition exists. So, it does not appear to be starter heat soak -- something else gets too hot. Open to more suggestions.

You mean disconnect the vac advance?

He meant unplug power to the distributor. Then see if it turns over with ignition disabled.

If it does turn over...Would still need to do the cold and hot amp draw test to see what's really going on.

This thing not turn over at all or barely turn and grunt to a stop?

Grunt to a stop: could be too much initial timing OR starter just not strong enough to do the job for some reason.

Bought a rebuilt high torque starter many years ago. It wouldn't turn the engine over when hot. Tested perfect at the parts store. New battery, new cables, same problem. Opened the starter up and found a small armature in a high torque case. Needless to say, it was weaker than the weakest starter ever made for Pontiac engines.

Clay

No change with HEI wiring disconnected. Couple of clicks and a whining sound from the starter, maybe moves a little but not even part of a turn.

Doesn't matter whether timing is at 0, 12, or 22 degrees initial.

Doesn't matter whether the starter itself is hot or not. Engine doesn't even have to be blazing hot, just running for 5-10 minutes will do it.

The solenoid just engages the drive and closes the starter circuit, correct? Drive engages and starter turns a little so I think the solenoid is doing its job.

I guess it's off to a shop to do load tests etc.

Solenoids will/can kick the drive gear out and still be bad. The copper lugs or disc can be worn out and not send power to the starter motor. Or send very little power to the motor. Those can free rev/bench test fine but not make enough power to turn the engine over.

Same thing can happen with poor brush contact. From brushes worn out, broke tension spring, wires screwed to brushes came loose, etc..

Clay

Yup. I fully expect that the starter amperage draw will not meet specs--assuming the wire on the "S" terminal has proper voltage during cranking.

Just to ask the question...can you turn the engine over when warm by pulling on the accessory belts, or putting a socket-and-ratchet on the damper bolt? This isn't a matter of a seized engine--right? Torque converter clutch not stuck "engaged"?