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View Full Version : VERY Loud Starter???



Shoeless
02-07-2021, 09:23 PM
Evening fellas,

As I'm inching closer and closer to the first fire of GTM 501, I'm checking things off my list, car wise, harness wise, and ECU wise. Fluids topped off, harness continuity check complete/harness installed, and initial configuration of the ECU in the works. Starts off simple enough with what type of injectors, tuning preferences (VE Tuning instead of MAF), Cam/Crank configuration, and then I go into the diagnostics step. This step consists of cranking the engine while the ECU tells the laptop the % chance of firing up and the sync state of cam/crank.

So I pull the spark plugs, warn the wifey I'm about to make some noise, but not fire the engine. I hit the start button and what seems to be a VERY noisy starter motor turns the engine over. I immediately stop and survey the scene as it seemed like a LOUD screeching sound. I crawling all over and see no issues. I grab a ratchet and give a couple manual turns on the motor, turns over just fine, no binding, no grinding no nothing.

I decide to give it a couple more cranks to continue to try and trouble shoot, while also paying attention to the laptop to see if the engine achieves sync state, see if % chance of firing hits 100%, and watching for oil pressure. On a GREAT note, sync state is achieved, 100% chance of firing pops up on the lap top screen, and oil pressure pops up to about 50 psi. All great signs that the ECU is receiving what it needs to actually fire up and run the engine.

I have the wife come out to the garage as I want to be underneath while she is cranking it so I can get a closer look. Sure enough it's the starter making this horribly loud sound.

Am I missing some alignment wise with the starter, has anyone ran it this, or is it possible I just got a garbage starter from Mendeola when I got my Stage 2 setup?

crash
02-08-2021, 11:07 AM
Sounds like a bearing in the starter?

Shoeless
02-08-2021, 12:18 PM
Sounds like a bearing in the starter?

Might be. Looks like I should pull this starter out and bench test it to see what it sounds like out of the car.

VRaptor SpeedWorks, LLC
02-08-2021, 03:17 PM
I'm not a GM starter expert, but doesn't GM sometimes have you install shims between the starter and engine block to set the clearance between the ring gear and starter pinion gear?

Shoeless
02-08-2021, 03:23 PM
I'm not a GM starter expert, but doesn't GM sometimes have you install shims between the starter and engine block to set the clearance between the ring gear and starter pinion gear?

I'm not sure, I definitely need to research this more.

Shoeless
02-08-2021, 03:25 PM
I just pulled and bench tested the starter and it spun just fine no noises.

I took a close look at the engagement area. Does anyone know if this is normal? Looks like a loose washer and a bearing?

https://i.imgur.com/78IUglP.jpeg

Shoeless
02-08-2021, 04:17 PM
OK a couple searching are revealing that I will need to shim this starter. With everything installed this is kind of a PITA, but I was able to get the starter teeth engaged, held in place, and carefully install the starter to see if I can get a paperclip between the starter teeth and the flywheel. The 0.025 paperclip would not fit between the teeth so shims are needed.

Shoeless
02-09-2021, 04:55 PM
I got in a pack of shims today, knocked off work after a 4 hours design review and went to work. I jury rigged the starter once again with a couple different shim sizes and landed at going with a 1/32" shim. Put everything back together and wouldn't you believe it, it sounds normal now. Wow one little shim, but understanding the engagement between the starter gear and the flywheel I can completely understand it now.

One step closer to first fire and that's all the matters right now :cool:

VRaptor SpeedWorks, LLC
02-10-2021, 09:22 AM
Woo-hoo!!

Erik W. Treves
02-11-2021, 02:01 PM
nice!