Can someone decode the following numbers on my 401 Buick Nailhead rear engine bellhousing: 1849046 4 I'm having starter issues with the gear messing with the flywheel teeth once I bolt the flywheel in place. I have a custom flywheel made by Bendtsens Speed Gem II. This adapter allows the use of a GM 4sp Muncie trans to be installed. I've been working with them and they suggested ordering a Powermaster 9501XS hi torque starter which I just got and it's not fitting into the opening on the block. Anyway I need to comfirm what engine I actually have as there are numbers stamped on the front of the valley plate was not readable so at least I can narrow down engine block by decoding the build date, etc Thanks in advance for responding to my question!
That number doesn't appear in any of my references. Look for the STAMPED number on the front of the block on the lip where the valley cover seals. You will need to clean if off to read it. Then, you can look up that number here. https://www.teambuick.com/reference/index.php#nailhead There were 2 different crankshaft for 401's. One was for Dynaflow and one was for the ST400 transmission. I am sure they used different flex plates and ring gears. You may have the wrong kit. Good luck! @Bangingoldtin may be of more help.
I gather that you don't know what year build your engine is? For the 63 to 66 engines you need the starter for that year as there is a 1/2" difference in the throw in length. For my 62 401 I bought all the parts for the conversion to a manual trans from Bendtsens i.e. flywheel, starter and spigot bush and it all works OK and I have lent my starter to mates who were having the same problems as you. @rockable types quicker than me but his info is spot-on and bangingold tin has been very helpful with Nailhead info .
Look at the second digit closely. Could the casting number be 1349046 4? That casting code is a for a 62-66 401. 62 and 63 engines used the crankshaft with the larger center hole for the DynaFlow transmission. 64-66 engines used a crankshaft with the smaller pilot hole for the ST400 transmission. The flex plates/flywheels differ, as does the starter. Sounds like there is a starter and flex plate/flywheel mismatch. Another possibility is the flywheel is wrong.
Do you have a web site address for the conversion to manual parts? I'm looking to do this for my 401, what gear box did you use? Thanks, Doc.
^^^^ Speed Gems (transmissionadapters.com) has the kits to do this conversion. They will need to know the year of the block and crankshaft to supply the correct kit. As far as manual transmissions, stay away from close ratio 4 speeds because of the engine torque curve. If you can find one, a Dearborn 3 speed is the ticket.
I've bought parts from Bendtsen's to do a ST400 swap onto my 62 401 and also to do a T-5 swap. ST 400 would not fit in my X-membered ch***is so I had to go to a T-5. I realise that the World Cl***T-5 is not strong enough to take what the 401 can put out but at 82 years of age I'm not looking to burn rubber and with the torque of that 401 and my 3.88 rear axle ratio I don't think I need the first 3 gears LOL. The link for Bendtsen's is as posted by @Bangingoldtin above and I've found them great to deal with and their parts fit and work.
I think we scared the OP off. @swifty, what length tail housing do you have on your ST400? - they made 3 (4",7", and 11"). I am using the 4" one because of my x-member.
The Jalopy Journal
