D100Guy

Are they the same flywheel? I ask because i am looking for an OEM flywheel to replace the one on my 74 Dodge D100. The original is not serviceable even after having it turned for resurfacing. the original is about 14 1/2 (approx) inches across in diameter. I bought one online from a company who claimed it was the correct one but after measuring it.... its too small and they do not have the correct size one. So before i order again i need to know if they made any differences in the automatic flywheels...i.e...(no holes drilled for pressureplate attachment.) Any info would be greatly appreciated.

Oh yeah and what year flywheels are interchangeable?

fivepoint

Automatic and manual flywheels DO NOT interchange.

D100Guy

Thank you soooo much for that info...now i have to find a manual flywheel for it. I will post a pic of the original one that got turned....that thing is still pretty ugly in my opinion....the surface feels smooth but you can still see the results of hot spots.

D100Guy

The OEM one on the left that had the surfaces turned. and the incorrect (too small) replacement on the right

measuring OEM

measuring wrong replacement

fivepoint

Its a Dorman part#04626. New one will cost about 120.
14.5 OD 143 tooth ring gear?

D100Guy

yes it is

1966sportfury

the automatic has a flex plate the ring gear is on the torque converter

D100Guy

yes that would make sense....looking and pricing the flywheel at this moment. Fivepoint was right....about $117 at Rock auto is what i have found so far. Let me correct that...about $109 w free shipping through Amazon.com...when in the hell did they get away from just books?

scotts74birds

Some real helpful folks here! I found frugalmechanic.com is good for comparison shopping. But you HAVE to have the right part # first. I have found the Amazon site to be really good at prices. No taxes and free shipping over $25 purchase. I live in a small town and have been trying to support my local NAPA guy. But everything I have bought from him in a NAPA box, has failed again within 2 years. Sad

D100Guy

Yeah i hear you dude...for a min everyone was saying for awhile go to NAPA and you will get a better quality parts...seems that didnt last long. I did see one on Amazon as i mentioned but i actually found one at my local Advance...actually went to the website first then took the part number into the store and ordered it....wont get it til Friday but at least i can continue putting things back together when i do.


i wonder what that smaller wheel i have would go to...its a 130 tooth and you can see the approx measurement in the photo.

Cranky

Do you have a granny gear in your transmission and is the truck a 4wd? Some years back, I had a 79 D300 with a 360 and a granny low 4 speed with that big flywheel. Just can't see that flywheel being in a 100 unless someone ordered it with the heavy duty trans.....the smaller wheel came in cars most of the time and light duty trucks.

D100Guy

Well thats the flywheel in the picture that i took out of it. No granny gear unless you are considering the High ratio first gear. Got the replacement flywheel however the pressure plate bolt holes are machined smaller than the original ones so now i have to go and get some smaller bolts to use tomorrow since nobody works on the Holidays in this town....and its a 2WD 3sp

challenger

if your still needing one let me no as i have one , sorry i was late at getting to this thread

D100Guy

Hey Np the parts store ordered another in case there was a fluke with the one i got i dont believe so but thats what they are doing and i will bring the pressure plate bolts with me and see if the holes in the ordered flywheel will fit the bolt(s). I really believe they machined smaller holes on the replacements. I am also going to find out what size holes those are in case it wasnt a fluke sitution,

Also Challenger will that one you have need resurfacing?

challenger

it will need refacing , its been sitting since 94 and was out side for a bit but it was refaced when i put it in my 78 but if i remember it was the first time for it so it has plenty meat on it left and the bolt holes should be at .448 +/- .002 and the center hole should be at 2.158 +/- .002
let me no if the new one comes in if its right

challenger

also i can clean it up to see if it actually needs to be refaced as i need to anyways

D100Guy

See the truck i am working on...that flywheel sat on that thing for about a year outside and when they tried to resurface it....they could not..it kept getting really really hot on the machine plus it had alot of hot spots in it. I think it was just toast from use. Well you can see in the pics above how it looked after the attempt to resurface it.....but will let you know if i can get it sorted out with the parts store or if i go and find some bolts that fit.

D100Guy

update.....unless i find an original flywheel...it seems all the aftermarket ones come with 8 mm holes for the pressure plate mounting. Would not have know til i went to get some bolts for the flywheel today. I wanted to see if i can find some with the correct non threaded shank size just before the threads start. Some guy who rebuilds old hot rods was looking at what i had and chimed in to relay the info about how they switched to smaller metric bolt holes.
The thing that kills me is this....none of the suppliers of flywheels new this. And even when they had someone who deals with manufacturer on the line who had all the tech specs in front of them (supposedly) no one knew the bolt hole size had been changed for the re-manufactured stuff. So if the person is looking at the original mfg. specs i guess they would say "yes" it has the 3/8 inch mount holes for the pressure plate.
I will add that here in the days of computer screens showing this and that...no one likes to get up off their duff to actually look at the product in their warehouses. So what happens....the send out the flywheel with the new size bolt holes and have no idea that they have been changed. But anyway i got my flywheel at the machine shop getting the holes drilled to original mfg size to accept the original pressure plate mount bolts.

D100Guy

ok update...after all this flywheel hunting i wound up with 2 that i can use. A new one with the correct size machined holes and a used one off of a 88 dodge truck...so i used the new one and mothballed the used one....now I grew up on Chevys so a few of the things i see on this 318 causes me to ask questions......the main question

Can anyone tell me what this hole is near the back of the block near where the starter mounts? there is one in the front of the block but its closed off but this one is open...what is this port for?

This is the one in the front of the block on the driver side (none on the passenger sides at all) this one was not machined all the way through.


this is the one in the rear...the hole is open...can see right up into the underside of pistons wtf is this hole for?

closer shot



any info would be greatly appreciated.

studruss

just looked on my 318 block and the front one is not all the way the rear one does not go into the crankcase. it must be a drain for behind the flywheel

D100Guy

i will look again....i may have just freaked when i saw that open hole there....i did not notice it when had the engine out and working in the pan area. I could have sworn i saw the bottom of a piston..but....i will look again.

D100Guy

nevermind.....feel like a bonehead after deciding to put my pinky finger in there once i realized it wouldnt get stuck...lol. Its the area in front of the flywheel. Yeah its just a machined hole that allows you i guess to inspect for leaks or whatever.

Studruss it was as you said.

I had such a hurdle dealing with this flywheel every thing i come across as of late puts me in "worry wart" mode.

D100Guy

Latest update......the D100 is back together for the most part. Got it started today.....only thing left to do is reposition the y pipe i have it angled down too far and i have to find out the problem in the gas line as to why no fuel is being pulled to the fuel pump from the tank...pump is new and work as i put some fuel in a glass jar and checked to see if the pump was pulling fuel out of it ..and it was. So believe there may be an issue with the rubber hose on top of the tank connected to the fuel supply line.