454 starter confusion and some clarity.

[Eyez Open]

Like most here I have had to replace a starter in an 83 454. To say finding a new starter was interesting would have been an understatement. I did however finally settle on one that has worked quite well until I reset my timing my new found compression twisted the starter. Needless to say, I found there is much more to finding a starter than just the unit itself. It is quite a process to marry all the correct parts to the engine in your RV.

Have a read below one article goes into it and another does seem to resolve the issue.

https://www.hotrodders.com/threads/454-starter-problems.457586/

http://rmcavoy.freeshell.org/starters.html#shim

I am about to attempt the below solution for my own personal dilemma...

As mentioned in the various drive end descriptions, starters that bolt to the block requires special bolts with a knurled shank to ensure a snug fit in the holes and prevent the starter from moving. The traditional size for these bolts is ⅜"-16 thread with a corresponding ⅜" diameter shank.

Many newer GM starters use bolts with a slightly larger 10mm shank that will be a sloppy fit if used with ⅜" bolts. This can be an issue with some remanufactured starters that have been fitted with an incorrect (newer style) nose cone with the larger 10mm holes. Or when installing a newer style PMGR (Permanent Magnet Gear Reduction) starter onto an older engine. I believe GM offers some special bolts just for this purpose. GM # 12338064 bolts have a 10mm shank combined with ⅜" threads and are 4.330" long. And GM # 14037733 have a 10mm shank with ⅜ threads and are 1.66" long.

[Oz]

Thanks for the detailed info!  Let us know how it turns out.

[Eyez Open]

Thanks for the detailed info!  Let us know how it turns out.

To better understand just what is out there i will do a cut&paste from another forum..
https://www.hotrodders.com/threads/starter-bolts.428866/

YES they did.. blocks cast up to the end of 1981... were SAE... blocks cast 1982 up

there is a cut off date... i am not sure of the exact date of the change..


3/8 is .375"
10MM is .392 give or take..

3510 starters with the bigger longer solenoid have starter noses drilled for the 3/8 bolts and knurl diameter..

3510M starters have a shorter solenoid and have starter noses drilled for the 10MM starter bolts and knurl diameters..

stick the bolts thru your starter in a normal direction.. where the thread and knurls stick out.. there should be NO WOBBLE to them in the holes..

hand thread your bolts in the block.. the knurls should fit snugly in the counter bored holes..

to tell if the starter is mounted with the proper bolts... loosen them 1/2 to 3/4 turn.. and see if the starter wiggles..

the starter gear distance to the flywheel is held in alignment by the knurled section not the torque of the bolts in the holes.. if the holes are big enough to run a 10mm bolt thru.. its too loose to mount with 3/8 bolts.

there are a few ways to fix this.. that may or may not work as good as a proper fitting starter nose.. some alternator shops may have the stainless shims that were used to mount a 10mm alternator with a 3/8 bolt. this will tighten the clearance around the knurled section if the shim pieces are long enough to not slip upward.. this is not really a long term fix.. i have never measured the shim thickness .. probably .008 or .009 thick.. there are thin wall K line valve guide liners available in .375" that have a 0.15 wall thickness there are other variations. also.. i use these with a letter Y, .404" drill to rebush GM tbi throttle shaft bores.


How this ended for now.

Dorman AutoGrade 3/8-16 Inch Thread Hex Starter Bolt
Part # 678-107 Line: That bolt does have a 9.9 millimeter shaft and sae 3/8th threads. But it is 1/2" to short. Sad actually if fit quite well into the starter, no slop. But it was a no go.
https://www.oreillyauto.com/detail/c/dorman-autograde/dorman-autograde-3-8-16-inch-thread-hex-starter-bolt/dag0/678107/v/a/3603/automotive-van-1983-chevrolet-p30


Dorman HELP! 3/8-16 Inch Thread Hex Starter Bolt
Part # 45658 Line:https://www.oreillyauto.com/detail/c/dorman-help/dorman-help-3-8-16-inch-thread-hex-starter-bolt/mtm0/45658/v/a/3603/automotive-van-1983-chevrolet-p30
Now this bolt is an OEM replacement that some find successful. But it is sloppy in the starter nose cone, I've installed the starter using these bolts but I will continue to keep an eye out for a bolt with a 10mm shaft and SAE THREADS

Still having issue's, there seems to be some confusion on actual type of bolt. SAE vs Metric...

https://www.hotrodders.com/threads/starter-bolt-probems.404161/

[Eyez Open]

Well I finally found a working combination, it turned out to be a nose cone issue and the proper bolts. I went thru 4 different starters trying to find one that would work, all these starters were spec, all had the bolt holes drilled in such a manner that allowed a lot of slop. That slop allowed the starter to twist, which allowed the drive to be misaligned enough to bind/grind..Hot starts were not going to happen.

By sheer chance I ran into a parts lady who had a long history with GM. She saw the problem, ordered in a starter for a 81 454, I took the bolts and placed them in the stater...and one locked into the nose cone, a solid mechanical lock. It turns out the knurling on the bolts locks into the starter nose cone and not the block. The original starter bolts do not lock in nor did the after doorman bolts. The key here was the bolt locking into the nose cone and not the block casting. The right bolt and the right starter will allow the bolt to enter the bottom bore hole of the starter   
but the bore hole in the top of the starter is necked down securing the bolt firmly in the starter preventing the starter from walking around on the block.

Below are some photos, one can see the correct bolt and starter, notice the bolt will not fit into to top of the starter, that is where the mechanical lock comes into place.

Well the pics are to large to post...update here i have resized one. The below pic has the right starter cone and the right bolt, notice the bolt will not enter the bore hole from the top...from the bottom up no problems.

https://www.oreillyauto.com/detail/c/ultima/alternators---starters/starter/dad3c6651e74/ultima-starter-remanufactured/ost0/r713217a/v/a/3603/automotive-van-1983-chevrolet-p30

The above starter states NOT for a 1983....it was the only starter that fit the RV correctly. Note: This HR is a 83 model yr, mfg date is late 82.

https://www.summitracing.com/parts/nal-12338064#overview
This bolt is designed to work with NAL-9000852 and NAL-12606096 starters.

[Oz]

Glad you finally got the right one!

[Eyez Open]

Indeed, 1983 model yr build date in late 82 with an engine build date 1981. 

Below is a somewhat detailed summary of what I experienced, a commentary made by summit racing customer

https://www.summitracing.com/parts/nal-12338064#overview

The Delco PG-series of starter motor had the aluminum nose-cone machined for larger bolts than the old-style 10-MT starter motors. As a result, THESE SPECIAL BOLTS are REQUIRED. Ordinary knurled starter bolts are NOT CORRECT for the new Permanent-magnet "mini-starters" from GM. The old starters, and the engine blocks they bolted to, use a 3/8 knurl. The new PG-series starters use a 10 mm knurl. These starter bolts have a STEPPED KNURL. The large part of the knurl fits the 10 mm starter housing, while the smaller, 3/8 knurl, and 3/8-16 threads fits the engine block. Using "ordinary" knurled starter bolts (even some advertised for "Mini Starters") will still allow the starter to move under load, as the knurl isn't big enough in the starter housing.
By: SCHURKEY from ND