Hodakaguy M38 Misc Thread

[RonD2]

[HodakaguyTom]

[wesk]

The gasket was not normally available by itself. But it did come with the tranny seal kit. Ron F's kit stocks that gasket still. Oddly enough the TM 9-1804B parts illustration is incorrectly labeled. B is actually the spring seat washer WO# 635863 and D is the gasket WO# 801733 (ORD# 7374976). The illustration fig. 07-2 on page 185 in the ORD 9 SNL G-740 is the correct illustration.
_________________
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[HodakaguyTom]

[RonD2]

Closest I can find for the copper washers (gaskets) are metric --- 8x12x1mm. Will keep looking.

I think Wes had a typo with "D is the gasket WO# 801763 (ORD# 7374976)".
The September 1955 ORD9 says WO-801733.

Tom, I sent you a PM. Thanks!
_________________
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari

[wesk]

3/32 ds is a bit thick for a standard copper solid washers. I would gues they are copper crush washers. EitherAN900- or MS29513- series. These are 3/32" thick. Since they are being used with a 5/16" dia. screw then the full parts number is AN900-5 or MS29513-5. Also do take note they are only used after engine serial MC74419 which is the switch to full fording kit engine. This was initially a test run during M38 porduction for jeeps MC51887 thru MC51988 Jan 1952 and full prodeuction with this new waterproof engine setup started with MC53262 Feb 52. If you have a 50 or 51 M38 it did not come with the copper gaskets.
_________________
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[HodakaguyTom]

[HodakaguyTom]

Let the fun begin....reassembly time!

With NOS shift forks in hand it's time to assemble the Shift Tower. I had disassembled it again since my previous post so I could prep/paint the tower while I waited for the NOS shift fork to arrive.




A little wear on the old fork.




Getting ready to install the shift rails & forks.




Inserting the indent spring, there is one spring/ball per shift rail.




Then the indent ball goes in on top of the spring.






I used a small punch to compress the indent ball/spring while also pushing inward on the end of the shift rail, you need to compress the ball far enough to allow the shift rail to pass through into the shift tower.




Positioning the shafts so that the shift rail interlock will fall down and allow the 2nd shift rail to slide all the way into the tower.








Both shift rails, shift forks and retaining roll pins installed.




Starting to assemble the main shaft....NOS goodness.




Low/Reverse sliding gear, 2nd gear and synchronizer blocking ring on the main shaft. A liberal coat of assembly lube on the 2nd gear bushing and the blocking ring. You just want to place the blocking ring on lightly so it doesn't bind onto 2nd gear, it should spin freely.






Synchronizer assembly slid onto the shaft.




Installing the snap ring that holds the synchronizer assy onto the main shaft.








Assembled. Check that the blocking ring still spins freely.




Bagged to keep it clean until it's ready to go into the case.




Next up is assembling the needle bearings into the cluster gear.




I'm using a dummy/installation shaft made out of Delrin to assemble the needle bearings and spacers onto. I was going to build an installation shaft/tool myself but Sal at vintage Jeeper has these units already sized correctly and ready to go, so I just added to cart...bam . The bearings are assembled onto the installation shaft then the entire assembly is inserted into the cluster gear. The cluster gear is installed in the transmission case then later the actual shaft will be driven into the case and through the cluster gear, pushing the installation shaft out of the case in the process and keeping the bearings nicely in place on the actual shaft.

The original bearing spacer is placed on the installation shaft/tool along with a washer on either side.






Here I'm using some O-rings to hold the needle bearings in place as I assemble them onto the shaft. After the first row of needle bearings are all in place another washer is installed then another set of bearings and another washer. Two sets of bearings and three washers on each end.














Applying assembly lube on the needle bearings.






Sliding the shaft/bearing assembly into the cluster gear. Once the shaft/bearings are slid into the cluster gear up to the O-ring you cut/remove the O-ring and continued to slide the assembly into the gear, cutting and removing the O-rings as you get to them.










And assembled.








Last up for tonight was loosely installing the NOS reverse idler gear & shaft.




A quick trip through the ultrasonic cleaner to remove the oil/preservative






Out of the ultrasonic cleaner....like new again.




Applying some assembly lube




And in place with the shaft loosely pushed in.








All covered up for the night.




More to come...

Hodakaguy

[4x4M38]

Neat trick with the orings. I made my assembly dowels from wood. Pretty easy, if you can’t find the nylon jobbies.

This whole post needs to be a Sticky. It’s as good or better than Novak’s or the other tranny/transfer tear down and rebuild books. Fantastic detail and photos!
_________________
Brian
1950 M38
MC11481
http://www.willysmjeeps.com/v2/modules.php?set_albumName=album372&op=modload&name=gallery&file=index&include=view_album.php

[HodakaguyTom]

[HodakaguyTom]

One step back and several forward.

I got the cart ahead of the horse in my last post by assembling the cluster shaft needle bearings before I dry fit the cluster gear into the case to check for thrust clearance. It's a good idea to check for clearance before assembly, if the thrust washers have worn into the case and the clearance is excessive then the cluster gear can move back and forth which can contribute to 2nd gear jumping out. Now's the time to check to make sure the case is actually usable (actually that time would have been before paint lol) so I unloaded the bearings from the cluster gear, removed all the grease and dry fit the cluster gear into the case with the counter shaft.










I measured the thrust with both a dial indicator and a feeler gauge, ended up being about .010", slightly on the snug side but plenty usable....I'm good with that clearance.






Played with taking the thrust reading between the thrust plates and between the gear & thrust washer.




Loading the bearings back up on the installation shaft and inserting them back into the cluster gear using o-rings like last time.










Assembly lube on the steel thrust washer.




And stuck in position in the case.




The small brass plated thrust washer goes on the end of the cluster gear, the two tabs on the back go into the notches on the end of the cluster gear.






The large thrust washer had a slight conical bend to it out of the package, when placed up against the case the edges of the washer were slightly elevated. This would cause uneven contact/wear on the bearing so I used a seal driver and a socket to lightly tap the washer flat and take out the bend. Test fit in the case and it's now sitting nice and square.








Cluster gear and thrust bearings sitting in the bottom of the case. This assembly will stay there until the final steps of assembly when the counter shaft will be installed.




Reverse gear installed.




Time to build up the input shaft.




The oil slinger will go onto the shaft first, the raised portion goes towards the bearing. This raised lip provides clearance for oil to reach the bearings if you are running a open face bearing. I'll be installing a sealed bearing.








Bearing pressed onto the shaft and snap ring installed.








Next up I'm plugging the oil return hole in the case. The original design uses an open face bearing on the input shaft, oil would flow through the bearing and into the bearing retainer where it would then drain back into the case through the oil return hole. Oil was stopped from traveling out along the input shaft by a single felt seal that didn't work very well so you would end up with leaks dripping out of the bell housing. By running a sealed bearing you won't have oil entering the bearing retainer so you don't need the oil return hole, plugging this keeps any oil in the case where it belongs. I'll be keeping both seals in place on the bearing to minimize oil leaks. Sealed bearings will run a Loooooong time and the bearing grease will remain uncontaminated from any debris circulating in the transmission.

A silicone plug with a coating of shellac will keep it in place. Install the plug from the outside and press it in tight, then use a razor blade to cut the plug off flush. A light coat of shellac on the inside will seal it up nicely.














Installing the input shaft/bearing into the case. I coated the outer circumference of the bearing with a light coat of Aviation Permatex to keep any oil from seeping around the bearing and into the bearing retainer.






After installation I went to test fit the bearing retainer and found that the snap ring was to large, it was interfering with the bolt holes as well as preventing the bearing retainer from sitting flush onto the case. There is a recessed area on the back side of the bearing retainer where the snap ring fits into, this snap ring was to large to fit into the recess by .029". I used a high speed rotary file to carefully remove some material from the inner diameter of the snap ring until the snap ring fit fully into the groove and provided the necessary clearance.




I'm also installing bolts with copper washers to eliminate the oil collector. With the sealed bearing the collector is no longer necessary, the input shaft needle bearings will get plenty of lubrication from oil carried up by the gears themselves. I applied a good amount of Anaerobic sealant to the bolts and washers to seal up the holes in the case where the oil collector was mounted.










Installing the needle bearings with a healthy dose of assembly lube into the input shaft.






Prepping the main shaft. Applying assembly lube on the needle bearing surface as well as the forward blocking ring.








And into the case.




Installing the rear bearing adapter, this is a snug fit and is tapped into place.






Sliding the bearing spacer onto the shaft.






Bearing installed on the shaft.




At this point the transmission is turned upside down and the cluster gear will fall into position, allowing the counter shaft to be pushed in, pushing the installation shaft out in the process and keeping all the needle bearings where they should be in the cluster gear.










Before fully seating the counter shafts I test fit the locking tab on the case. The tab was to wide and would have caused issues when mating the transmission up to the transfer case. I trimmed down the lock tab for proper clearance, test fit one last time using the gasket as a template and then fully seated the counter shafts/lock tab into position.










I picked up a NOS made in the USA bearing retainer but upon assembly noticed I could feel bind as I rotated the input shaft. I believe the small snap ring on the input shaft is contacting the retainer. Comparing the NOS unit with my old one I noticed the old one has a deeper machined recess than the NOS unit, allowing more clearance. I test fit the old unit and the binding is gone. Hmmm...I'll have to address this.








Assembled. Holding the rear bearing in position and spinning the input shaft resulted in smooth operation in all gears. Getting closer!









More to come....

Hodakaguy