Lately, my 2000 F150, 5.4L has exhibited a grinding noise upon attempting to start the truck. It almost appears as if the starter is not engaging. Sometimes, it won't start until the third or fourth attempt.

How do I diagnose the starter to see if it is the problem?



Jeff

 

Okay Jeff,

It sounds like the starter is milling against the flywheel. Basically, the pinion of the starter is not engaging but is still spinning and making the terrible noise.

This is generally a starter problem, but can be linked to a few other things as well. Quick checks are the battery and the two starter connections. A poor connection will not produce enough energy in the solenoid to engage the flywheel. This is a low possibility but easy to check.

The pinion of the starter is suppose to engage the flywheel before the armature/pinion begin to spin/crank. Issues that prevent this are pretty hard to determine from outside of the truck other than experiencing milling. Most likely issues are a milled down pinion that no longer has a chamfer to make engagement easier. There could be some corrosion issues around the plunger inside of the solenoid that actuates the lever to engage the pinion into the flywheel. You could also have some corrosion on the output shaft of the drive assembly. Most of these are not necessarily easy to fix.

Taking the starter off the truck is not too bad assuming you have the proper length extension for the ratchet. With the starter removed, you will be able to see the output shaft and the condition of the pinion as well as the ring gear. If the starter needs replaced, you are half way done with the problem. Looking externally and do not notice anything, you can energize the starter with a battery. Connecting only to the small terminal will make the pinion engage; connection only to the M terminal (the one with the strap) will make the pinion spin. By connection both the B+ terminal and the small one, it will engage and spin.

You can try to partially dissemble the starter which isn't very hard to do and put back together. There isn't any springs or other issues when taking it apart. Once apart you may notice some corrosion or something that you might be able to clean up. More than likely however, you will need to replace it.

This is something you do not want to let go for very long because it may end up running your ring gear if not already, which means alot more money. The starter does not randomly engage into the flywheel, there are predetermined locations. The flywheel always stops at or very near TDC of one of the cylinders. You could be trying to engage into a bad section, when it finally engages. Does it happen all the time, once in awhile or is this your first time?

My first starter did this once in awhile, but not 4 times in a row. It had a lot of corrosion issues and had to be replaced. Have anymore questions, let me know. Good luck.

 

Stormsearch:

Thanks for the reply. I bought the truck new in 2000. The grinding happened once at about 10,000 miles. Since then, it was grinding maybe twice a year. The truck has 90,000 miles on the engine now, and I notice the grinding happening more frequently; probably once a week. It may go several days without exhibiting any noise on start up.

I'll take your advice and check for corrosion. The battery was replaced at 85,000 miles (original battery). Then I will pull the starter and check. I'll check the teeth on the flywheel once the starter is pulled. Where is the ring gear?

Thanks,

Jeff

 

I would agree with you that 1/week is getting to be too much. A couple times a year can be expected. The ring gear is part of the flywheel assembly. You will only be able to see a small portion of it through the transmission bell housing.

Just thought that another possibility is a loose bolt on the starter motor. There is 3 of them for F150 so unlikely but possible. Good luck.

 

Stormsearch:

I removed the starter. No sign of corrosion. I had the starter tested at AutoZone. The pinion would not engage at all. The boys at AutoZone indicated that the voltage was weak.

With this being said, I bought a starter at NAPA which comes with a 3 year warranty for $145 with tax. I will see this week if the starter replacement was successful.

Thanks for your valued information.

Jeff

 

Starter replacement was successful! No more grinding when starting. Thanks to all. This is a great forum.

Jeff

 

Hey OE812, Just curious if replacing your starter has fixed your starter/flywheel grinding? I am experiencing the same thing in my 2000 f150 w/5.4 and it has started to happen a little more frequently now. I was thinking of dropping the starter this weekend and looking at the starter gears and other things mentioned. Please let me know if this resolved this problem.
Thank You! Tom

 

Starter is grinding again. About every 4th attempt to start. I'll have to pull the starter this weekend and check to see if the pinion is engaging. My OEM starter was tested and the pinion was "weak"; would not engage.

Life is great!

Jeff

 

did you ecver figure out what teh problem was? I am having this problem too now.

Brett

 

Brett:

I replaced the OEM starter with a 2 year NAPA starter and it has been grinding about every 4th start since March. I kept putting off pulling the starter to have it tested. But this weekend, the starter will be pulled and tested.

I will also inspect the flywheel to make certain I didn't damage it with all of the grinding going on (no pun intended). Follow Stormsearch's suggestions to diagnose the problem. Break the issues down by component. I have never had an electrical problem with a NAPA replacement component in my 26 years of being a backyard mechanic, but I hope the starter is defective. They stand behind their products.

I'll let you know how the diagnosis goes this weekend.

Good luck with your problem solving.

jeff

 

Pulled the Napa replacement starter today due to more and more starter grinding noise when trying to start the engine. After removing the shroud at the bellhousing and turning the flywheel, I determined the noise to be coming from the damaged teeth on the flywheel.

My speculation is the OEM starter chewed up the teeth on the flywheel but only along an 8" section. It is bad enough to create the noise.

I've already gotten mechanic estimates of 6 hours of labor, $65 for the flywheel, plus cost of the rear main engine seal and tail shaft seal. Total cost around $500.

Has anyone ever changed the flywheel and if so, how difficult is it and which tools are needed?

Thanks,

jeff

 

I have the 4.2v6 w/4r70w tranny

You're going to have to slide tranny back. That means drive shaft removal and possibly tranny cross member. Undo the bolts (2) after removing the four flywheel/converter nuts (and marking it for location on reassembly - a new ring gear...make a mark on the new ring gear with the same orientation as the old to avoid vibration problems). You are going to need a ft-lbs torque wrench/with socket to unbolt the flywheel so the tranny has to slide back around 4"(Do not pull on wiring harnesses!!!Remove if neccessay). Support the tranny with jack and piece of wood to spread the load on the pan. Support the motor likewise. Tranny will not like comming off motor easily (guide pins from Ford were not specially coated from factory, so they will seize. You can access the torque convertor bolts from the bottom left side through the inspection cover(it pry's out) and remove the starter). Match the new ring gear exactly to the old(the back of the old ring gear leaves the impression on the crankshaft with the locating mark. Use red locktite and torque the bolts half the max value the first round, and then go over them to the final value the second (gear/crankshaft). Match new mark to covertor mark (not sure if this is neccessay with new ring gear) and torque the 4 convertor nuts on with locktite as well (don't want these comming off).

Make sure convertor nose (into crank) has a little anti-seize, as well as the tranny/motor guide pins, and tranny/oil pan bolts. email for torque values if you don't have the Haynes manual. I'll look up any torque value you need. I would leave a whole Saturday for this job. Goodluck, you'll need a helper/gopher on this one. PS. If your rear main seal isn't leaking, don't worry about it if you'r trying to save money. But if the motor had alot of miles on it, now would be the time (money well spent in most cases and not more than 1/2 hours work while already changing ring gear).

 

menmytruck:

Thanks for the very detailed instructions. This is more than I bargained for. I sent my truck to a mechanic shop for this. He has all the mechanics tools and hydraulic lift to do this job. The thought of working on my back on this all-day project is too much.

Total cost will be around $550 with the rear main seal change. Maybe a few dollars more for the tailshaft seal if it is leaking. Bummer, but I don't have a choice but to crack the wallet.

Thanks again.

jeff

 

The reason it's only along an eight inch section might be because it's cracked. Sometimes the flexpates flex so much that they develop cracks between the holes in them, this causes misalignment.



Here's a pic of a cracked bolt pattern.



You might want to inspect the one that the mechanic removes. Either way, good luck with it.

 

I have 2000 that the starter went out in, and since we have put 3 starters in and it just keeps burning them right up. We just changed our ignition switch and put another starter on it and it again burned up the starter. the minute you start it the solenoid will not shut off and it ends up with a terrible grind (flywheel) and there goes the starter. Can anyone tell me what is wrong here?