Just Replaced LS400 Starter, Strange Noise Upon Startup

[RenaissanceReddy]

Hey guys! I'm new on this forum. This is my first post, but hopefully it's an interesting one. I have a 99 LS400 with 152k miles on it. A few weeks ago, it started taking more and more turns of the key to start it, until one day, when all I got was the infamous single click. So I figured it's time to replace the starter and ordered a Denso Remanufactured one. It came in late yesterday, and my friends and I got started. We finished today and got the car all put back together. When I went to start it, it started right up! However, right after it turned over, there was a very high pitched whining/whirring noise ( like something spinning very quickly) which lasted a second or two. I've tried starting it about 12-13 times since then, and it does it almost every time, although the noise has gotten a bit quieter.

My friends and I immediately suspected that the noise was coming from the starter not disengaging and pulling back out of the flex plate after starting it. After doing some quick searching on this forum, I figured we were probably right about that theory. Is this because we possibly didn't seat the starter properly? Maybe it might've been at a slight angle?  But the two 14mm bolts went right in and we tightened them properly. The starter seemed like it was very stable and properly fitted. Or is this just an issue with the starter itself?

In any case, my main concern is... Will this cause any long term problems to the flex plate or something? Will the new starter go out quickly? Basically, what should I do at this point? 

Thanks in advance guys!
Karthik 

 

PS. I have to take the LS400 on a 900 mile road trip from Chicago to NY tomorrow . That's why I'm kinda anxious and worried about this noise haha. At least we got the starter replacement done fairly quickly and on time. I have to say, although it was an annoying job, it really wasn't as bad as I was expecting! 

 

[sha4000]

Is your check engine light on? It does sound like the starter was not disengaging but that's just a guess. You could have also gotten a bad starter. These things do happen. Hopefully nothing was damaged with that noise. All I can suggest is that you guys tear everything back down and bench test the starter.

[landar]

Welcome Karthik.

I think you are right on with the starter not disengaging immediately and being spun by the motor for a moment. Could be that the starter is partially defective, maybe a weak spring to retract the gear. I always bench test my starters and then once installed, I try them again before the engine is all back together. On the LS, I jumper the starter solenoid to the battery to get it to crank before reinstalling the manifold. Just FYI for future starter changes.

You know, I don't think I would do anything at the moment except keep an eye...er, ear on it. If it is a defective return spring there is nothing you can do about it but tear it all down again. I doubt that it will damage your flex plate although the starter does get a bit more wear and tear. You might take a peak at the teeth on the bottom of the flex plate thru the cover and see if there is any excessive wear. 

Let us know what you decide to do. 

[Exhaustgases]

Its not a competition or a race to do something like a starter replacement. Its better to spend 2 days or more and do it right than goof things up trying to rush it. Even the so called professional mechanics mess up (actually allot) from trying to speed through a job.  It could be that the gears are meshing too tight, the bendix clutch is not working right. So does it make gear noise when cranking the engine? It may just clear up with use too. And meeee toooo always test a starter before installing especially a very difficult install like the LS. I also did my LS like Landar did, do the double test, one on the floor, the other right after its bolted on.

"Not as bad as expecting"   ??? It must be different on that year. Its a very nasty job on a Generation 1, the crispy electrical connectors are what makes it just bad. And the rear coolant cross over manifold and the wire loom. And the next to zero clearance between the engine and firewall, it would probably be less trouble to take the engine out to do it.

[M.Yasir]

It is indeed a nasty job, almost whole of your engine is ripped apart...

[sha4000]

Lol, it's easier if you have 2 ppl to lift that heavy intake.

[RenaissanceReddy]

UPDATE - 

First of all, thank you all for getting back to me! I really appreciate it. I read all of your responses and decide to just wait and see what happens before I do anything. And I guess it paid off! I got to New York just fine. And after a few days of making the noise while I was here, it completely went away!  It hasn't made the noise at all in over 10 days. And the startup feels and sounds just fine every time. I'm still not exactly sure what it was. Maybe it was just an issue with the starter itself that for whatever reason fixed itself haha. The starter definitely seemed like the likely culprit because our installation went pretty smoothly. In any case, I'm happy and worry free :) 

 

On 5/19/2016 at 9:11 PM, sha4000 said:

Is your check engine light on? It does sound like the starter was not disengaging but that's just a guess. You could have also gotten a bad starter. These things do happen. Hopefully nothing was damaged with that noise. All I can suggest is that you guys tear everything back down and bench test the starter.

There wasn't a check engine light at all. But I am glad I waited before I ripped everything back down haha. And yep, lifting the intake manifold out without a second person would've been insane.

On 5/19/2016 at 2:55 PM, landar said:

Welcome Karthik.

I think you are right on with the starter not disengaging immediately and being spun by the motor for a moment. Could be that the starter is partially defective, maybe a weak spring to retract the gear. I always bench test my starters and then once installed, I try them again before the engine is all back together. On the LS, I jumper the starter solenoid to the battery to get it to crank before reinstalling the manifold. Just FYI for future starter changes.

You know, I don't think I would do anything at the moment except keep an eye...er, ear on it. If it is a defective return spring there is nothing you can do about it but tear it all down again. I doubt that it will damage your flex plate although the starter does get a bit more wear and tear. You might take a peak at the teeth on the bottom of the flex plate thru the cover and see if there is any excessive wear. 

Let us know what you decide to do. 

Landar, I actually wrote this post in hopes that you would comment haha. I saw how helpful you had been for others with their issues, specifically regarding starters. So it made my day to see your post on my thread :) Thanks for your advice on waiting to see what happens; it definitely paid off. And I will definitely test starters in the ways you described before installing them moving forward. Great advice. 

 

On 5/21/2016 at 2:30 AM, Exhaustgases said:

Its not a competition or a race to do something like a starter replacement. Its better to spend 2 days or more and do it right than goof things up trying to rush it. Even the so called professional mechanics mess up (actually allot) from trying to speed through a job.  It could be that the gears are meshing too tight, the bendix clutch is not working right. So does it make gear noise when cranking the engine? It may just clear up with use too. And meeee toooo always test a starter before installing especially a very difficult install like the LS. I also did my LS like Landar did, do the double test, one on the floor, the other right after its bolted on.

"Not as bad as expecting"   ??? It must be different on that year. Its a very nasty job on a Generation 1, the crispy electrical connectors are what makes it just bad. And the rear coolant cross over manifold and the wire loom. And the next to zero clearance between the engine and firewall, it would probably be less trouble to take the engine out to do it.

I only meant it wasn't that bad in the sense that I had read up so much about it and saw hundreds and hundreds of people complaining about it. I still consider myself a beginner  (at best) at wrenching, so I went in expecting the worst. However, I do like to think I'm more patient than most people. I don't stress or get frustrated easily. And patience is definitely required for a job like this haha. Even though it wasn't as bad as I was expecting, it was definitely still an annoying job overall. I guess it just was a little more straightforward than I had imagined it in my head, that's all.  I was also lucky because my two friends who helped me are much more experienced at wrenching than I am. Couldn't have done it without them. 

 

All in all, great first experience posting on this forum. Thanks again to everyone who responded! 

[RenaissanceReddy]

On 5/21/2016 at 8:57 AM, sha4000 said:

 

Sorry, I have no idea how or why this got made into another post. Mods please delete this post

[sha4000]

Glad it's working out for you. Just keep a good ear out for any future issues with it and have your plan of attack ready.