Flywheel for motor swap

[wiboater]

I pulled the Bellhousing off of a 1938 Dodge RC 218 engine, 25 inch block. The bellhousing is different on the transmission side They gave more room for the clutch plate. I Took some pictures , will try and post them later. You are probably right about the flywheels though too. The one that I had in the 36 I had replaced a while back. The one that came out of the truck was thicker on the block side . I'll have to measure them tomorrow. Anyway I should be ok now with the 218 bellhousing having more room inside at the top.  

  I did just realize though I would have to use a 37 or 38 transmission though because the 36 has the shifter moved forward. It sits on part of the bellhousing. I'm trying to find a different flywheel now. 

Edited November 17, 2019 by wiboater
Wanted to add something

[wiboater]

anyone know the dimensions on the 230 Ci. flywheel ? Thickness where it bolts on. and from there to the face. Just thinking about maybe taking a 218 flywheel in and having a machine shop take some material off to make it a 230 flywheel. 

[wiboater]

I called the guy I got the engine from and he found a flywheel for a 230 he had. It was thinner and now the clutch fits fine. Transmission is back in etc. Thanks for the info about the clutch differences. 

[wayfarer]

Good to hear that you have it together.

[wiboater]

Anyone know the reason the holes on the flywheel are drilled so it will only fit on in one position? Just curious. I can see if it were balanced on the engine at the factory but if you replaced one it would be different. 

[JBNeal]

one hole is offset probably so the flywheel isn't put on backwards

[wiboater]

wouldn't it still fit backwards though? 

 

[JBNeal]

Not without a blowtorch and a BFH

 

Rather than go into the geometry, as an exercise simply trace and cut out the flywheel holes on paper...then align the paper holes to the crankshaft, then flip the paper over to see the difference...

[kencombs]

On 12/6/2019 at 10:14 AM, wiboater said:

Anyone know the reason the holes on the flywheel are drilled so it will only fit on in one position? Just curious. I can see if it were balanced on the engine at the factory but if you replaced one it would be different. 

My guess:  The parts are balanced separately when new but with a 'dummy' standard flywheel or crank attached.  The hole offset assures the real part is assembled as the dummy was when balanced.

[ggdad1951]

if you put it on backwards the engine will turn the wrong way!  ?

[falconvan]

So this is what I’m going to try on my a Desoto; going to pick up Plymouth running gear this weekend to use the trans on my 237.

[Jobrated_man]

On 12/6/2013 at 2:58 PM, wayfarer said:

You might want to check that engine id code.

The 230 is a 23" engine.

I would be shocked to see a 4-bolt crank pattern on any 25" crank.

The 172 tooth ring gear started in 1957 on the v-8's, and the crank flange projection of the pre-62 v-8 is the same 1.1875" as the L-6.

The bell housing will be different between the 146 and 172 wheel simply due to the wheel diameter and the resulting starter location. 

wonder if this thread is still alive., if so, i have a question.  i have been given a P26 engine to replace the blown one in my 1959 Dodge truck. Now this P26 block for some reason has a 4 bolt crank, and matching flywheel. But the flywheel had the 146 tooth count, so i replaced the ring gear with the 172 version, which was on the 1959 engine.  will there be a problem with this, using the 12 V starter and this 4 bolt crank/flywheel?

[JBNeal]

It's my understanding that the 8-bolt crank was employed to deal with the resisting torque of fluid drive couplings.  I'm guessing that if the 4-bolt and 8-bolt flanges have identical geometry, then additional holes cold be machined...not something I would try with a handheld drill.  I was also under the impression that the 8-hole pattern was not symmetrical, so there's that detail to verify.  I think the flywheels are interchangeable, but there must have been a good reason why Chrysler upgraded to to 8-bolt crank for the flathead torque monsters... ?

[Merle Coggins]

8 hole cranks do not have symmetric holes either. There is one that is slightly off from the rest so that my Fluid Drive would only go on one way. 

[The Oil Soup]

Another thing to consider is that the flange on the 230 crank is 3/16” further back than the flange on the 218 necessitating machining the starter mounting pad that 3/16”.

[anatole]

Hi,

perhaps someone could help me out as I have a 1938 RC with a P26 engine and a 172t flywheel.  I believe that the 3 speed is original to the 38.

 

I bought the truck as above and within less than dozen starts or close to it, the starter that came with it, Chrysler 1689-340, had its Bendix gears destroyed. I bought a replacement, which was a Wilson 1828, and this one also lasted just about the same, except this time, the Bendix got engaged and stuck. 

 

I removed the starter and I could hear lose piece inside and also some rubbing of the Bendix against my flywheel.

 

I measured the Bell Housing to the flywheel and I get 23mm or very close to 1" rather than 1.18 which I believe the 1828 starter would project.

 

Another person from forwardlook.net did point out that the P26 used MDG-6001 which is a Wilson 1826 vs my MDM-6001 which is Wilson 1828. But none of the vendors mention the crank projection.

 

I would like to switch to a Gear Reduction starter to give me more room to work and not fight the oil lines as well as having a higher torque that may be required for 172t flywheel. Something like this: 1956 Dodge Power Wagon Mini 12 Volt Starter – Snap Rebuilders (snap-usa.com) which is a replacement for MDG-6001 but I will have to reach out to them.

 

Q: does anyone know of any GR starters, not DD, that has a 1" crank projection and would work for 172t flywheel?

 

Thanks!

[QEC]

Hhhmmmm.... The P26 is a 1955 230". All 230's have a crank extension dimension of 1.185" from face of block to face of flange. This is the same dimension for all of the L6 and L8 EXCEPT FOR the little Plymouth 201-208-218 engines that have a 1.0" extension.

These Plymouth flywheels are identified by only having 4-bolts.  In addition to the usual 8-bolt arrangements there was also a 6-bolt crank/flywheel used in/around 1959-60 in trucks. It is the same bolt circle as the 4 and 8 bolt designs.

Whew...Now, if you use a 4-bolt Ply flywheel on a 230, the flywheel will sit 0.185" farther aft and there is a good chance that the starters will do what you have described. So, before jumping into some fancy starter you really need to verify which flywheel is installed.

Just curious, is yours a 12 volt conversion?

[anatole]

Hi,

I'm a newbie when it comes to Mopar engines or any American brand. I have read about 4, 6 and 8 bolt flywheels.

Yes, this is a 12v conversion.

You are correct that the 230" and I took some pictures today as well as some measurements.

It is a 6 bolt with 2 additional holes that I see but they don't go thru.

Here are some measurements:

flywheel thickness: 3/8

housing thickness: 5/8

from outside of the housing, where the starter mounts, to the flywheel: 1.5 inch and to the end of the flywheel: 1" 7/8  (1.5 + 3/8)

172t flywheel.

 

I don't think the Wilson 1826 will work as the gear OD is 1"1/8 while the 2 that i ruined have a 1" OD.  All are 9 teeth.

 

The eaten gold gear was the Chrysler starter that came with the truck when I bought it. You can see the teeth are destroyed.

The other Bendix is the Wilson 1828. It should have been the correct replacement for Chrysler 1689-340 starter but as you can see, the teeth are OK but the face has been griding against the flywheel as if the Bendix projection  was too much. The other two pix show the 6 bold and the flywheel where someone counted the teeth.

 

I will also need to source the inspection cover, but that the least of my problems for now.

 

Thanks!

[QEC]

Just a couple of random thoughts...

The flywheel nuts/bolts do not generally use a split lock washer. From your photo it shows a decided lack of threads past the nut where one or two should be seen. The oem used a thin external tooth washer. Make sure that your nuts are tight. 

Yes, you have a 6-bolt flywheel...but, is it an oem 6-bolt? or something else? It is certainly possible to drill additional holes in a flywheel, even on a shop drill press, since the holes do not have to be precise. You will only be able to verify which condition upon removal and visual inspection.

 

The dimensions you offer can only be compared to another known entity, i.e. a verified stock assembly. Hopefully someone can jump in and offer their help.

[anatole]

Good observation on the split lock washers. I did find a picture of another flywheel with the external star washer.   

 

I believe that the bolts are tight but if I decide to swap the washers, I'm guessing that because I can't get my torque wrench in there, that it's not advisable to swap 1 bolt at a time without a TW. 🤔

 

Unfortunately, I don't have enough info on my truck and given everything that I've wrong with it while restoring the body, I doubt if the PO used a 4 bolt and drilled for 6. I read that the 8 are mostly common in the larger Hemi engines, most/all of the Power Wagons and later V8 civilian cars.

 

I will try and reach out to few starter vendors and ask for their projection measurements. The only one that I have asked was RobbMc but their starter had threads on the starter housing that were the same as my bell housing (7/16 14) which sounded strange unless the bolts would go thru the bell housing, without a thread, into the started (the opposite of every Mopar truck/civvy prior to 56, that I can see

[QEC]

I am of the opinion that MaMopar attached the flywheel/fluid coupler/torque converter to the crank prior to laying the crank in the block so they would have had some means to torque the nuts. If you are worried about the amount of torque you can apply then set up a test assembly on the bench that you can tighten with a long 5/8 box wrench (what you will need to get to the nuts in your assembly). Check the torque with a TW. ...lather-rinse-repeat... until you develop a 'feel' for the proper number.

You could also experiment with a TW attached to the box end wrench to be able to get a number. I suspect that you will end up using a smaller inch-lb wrench due to the length of the lever arm, but at least you will have a number.

Me? I just give 'em a healthy grunt or two and call it good. Nah, no science involved.

 

As to the number of bolts, keep in mind that everything (L6, L8, A, B and RB) used the same bolt circle design (exc for the early L8). A 1960 truck with a B or RB engine (like a 413) will have a 6 or 8 bolt wheel that interchanges with a '55 Dodge 230.

Also keep in mind that the 172 tooth wheel is the same OD as the 146. The starter pinion changed to accommodate the different pitch.

 

Yes, the early Chrysler stuff can look like a bag of snakes at times.

[anatole]

I'm 5'6". 150lb and have to use extension bars when it comes to very tight bolts like the head cylinders for ALFAs or SAABs where after you torque to 70lb initially, you still have to turn another 140 or 90 degrees, depending on the make and model. For this job, my concern would be if I don't have them as tight, but given these old cars and trucks, they withstand lots of torque and I'm not dealing with a gasket or afraid to damage the heads.