I'm preparing to build up my new 1994 7.3 to replace my current engine in my van. My current engine has my C6 plus GVOD, but the new engine has the E4OD flywheel still on it.

I'm planning on moving my C6 flywheel to the 1994 7.3. Is there anything I need to know or parts I need to buy to make sure this swaps over? It looks simple enough, but I just haven't installed one of these flywheels before (all my engine swaps were all C6's).

Also, do I have to worry about any part incompatibility since I'm moving from a 1988 to 1994? Both are van engines (oil cooler, diesel filter head, vac pump, etc) but that shouldn't really matter. Just making sure that my 1988 heads will mount on my 1994 block.

 

as long as you are keeping the C6, there is no problem. but if you plan on using the E4OD, the C6 flywheel will no longer work.

 

My new engine still has the old e4OD flywheel on it, which needs to go so I can put the C6 one on. But I'm more asking about are there any shims or specialty items that need to be bought when I do the swap?

 

nope. take the E4OD wheel off and bolt the C6 wheel on.

 

I am very tired and trying to figure this out. You are talking about "Flex Plates" with the welded ring gear. Why do you need to put the C6 flex plate on the E4OD? Is the C6 flex plate stronger?

It would seem like the two different transmissions would have different torque converters that are not interchangeable. I was thinking that they were very different transmission but I vaguely recall now that the E4OD is just a modification of the C6

I'm curious to know and also too tired to try to figure out why you would need to or want to swap the flex plates.

AHA! The ring gear on the E4OD flex plate is chewed up or the flex plate is warped or cracked! That would be a good reason! Did I figure it out?

 

OK let me guess again. You are using the C6 transmission, not an E4OD transmission. 10-4 I misunderstood and thought you were also installing an E4OD but wanted the C6 Flex Plate.

 

Yep. I'm tired too.

I'm trying to remove a e4od flywheel, to install a c6 flywheel.

 

Yeah, last night I was thinking that the flex plate, (or flywheel) bolted to the torque converter which was part of my confusion. It's been 22 years since I replaced an automatic transmission but only a few years ago that I paid a shop to replace a broken flex plate in a transverse mounted V6 FWD and I could see where it had broken all the way around the bolt circle but I was too tired last night to remember that.

To make this post not entirely useless: The dust cover under the ring gear and front edge of the torque converter is supposed to have a narrow rubber or plastic seal around the edge that mates to the bell housing. Probably an impossible to find part. The seal on mine was broken and missing in some places so I used black RTV to patch it up, which worked but now I have a better idea to make a new seal:

'Liquid (rubber) electrical tape' which is oil and and chemical resistant for use in automotive applications, could be used to make a new rubber edge seal for the torque converter dust cover. Just clean the edge removing any oil/grease or paint - go over it with some steel wool or fine emery-cloth/sand paper to scratch the surface for a better gripping surface and adhesion, then wipe it off with a clean rag or compressed air to make sure there is no sand-paper grit left on it. You wouldn't want that finding it's way to the main seals.

Then just apply some liquid rubber to the edge with the provided brush. You can wipe off or scrape off any excess before it cures. It doesn't have to be as narrow as the original seal, which is less than 1/8 inch wide along the mating surface, I think a 1/8 inch to 1/4 inch wide application is OK. After 5 minutes between layers you can apply more layers to build it up to be as thick as you want but one coat is probably enough. I think it's cured up enough to install the part after 4 hours which would be a good time, while it's still a bit soft but not sticky and will conform well to the mating surface. The full cure takes 24 hours.

Using sealants from a tube like the black RTV that I used doesn't work very well because it is too difficult to get a layer applied that is consistent in thickness - although you could install the part before the sealant is cured to correct that problem.

This 'Liquid Electrical Tape' is an excellent way to duplicate a good moulded wire terminal or cover & insulate a soldered splice or seal cheap after-market crimp connectors which are practically the only kind of crimp connectors you can find stocked in parts stores and hardware stores now days = cheap junk crimp connectors for use with cheap crimping tools that don't have much leverage. Nowhere even close to the quality of original factory wire terminals.

I have a can of liquid rubber, Star Brite brand "Liquid Electrical Tape" which is oil and fuel resistant, used to coat wire terminals, ring terminals etc., instead of using thin heat-shrink tubing and with more coats you can make them as thick as the original moulded terminals, ie, like the ring terminals on the glow plug relay power wires. I had to cut off the moulded rubber from some terminals to make some repairs to harness wiring using high quality ring terminals without plastic insulation so they could be soldered = Soldering assures 100% contact of all of the wire strands in any stranded wire splice or repair and is especially recommended for wires that handle high currents. The liquid rubber electrical tape worked very well.

Permatex makes a good one, you might find it in auto parts stores but it wasn't stocked in this flea-bit town. I used a different brand 'Star Brite Liquid Electrical Tape' that I found at a local hardware chain store. (I know I wrote that already). The product was good but the applicator brush attached to the inside of the lid was terrible - stiff and frayed in all directions making it more difficult to get a nice smooth application.

I plan to use that product over a lot of wire connections in my tuck, also over plastic insulated crimp connectors and splices to prevent moisture entry and corrosion, especially in wiring under the truck where I still have some problems to fix. (splices in wiring from the fuel gauge senders for one example). I think it's considerably better than heat shrink tubing and if you have to remove it later you can cut it off with a utility knife.

I wandered off topic with the electrical wiring/ terminal repairs. I just wanted to put something useful in this post to make up for two useless posts.

Sorry for another long post but honestly, it's the only way I can write and maintain concentration due to side effects of a medicine that I have to take 3 times a day.

Good luck on your project, genscripter!

 

Manual transmissions have a flywheel. Automatic transmissions have a flexpate. There is a big difference between the two.

 

thanks. i thought the terms were interchangeable.

 

I swapped my 89 7.3/e4od to the newer style flexplate, I believe both are interchangeable. One uses a stamped flexplate and spacer, one uses a cast ring gear and thin small diameter flex plate that had issues, which is no longer made.

 

A flywheel is cast iron and weighs about 40 lbs. A flexplate is sheet metal and weighs about 3 lbs.

 

Be aware some (most?) C6 trucks had the earlier design which consisted of a heavy "flywheel" with ring gear but no machined surface for a clutch, and a separate flexplate for the torque converter. I assume since OP mentioned C6 flywheel, he is referring to the heavy cast part.

Note that if using this older style flexplate setup, there is no separate crank spacer between the flexplate and crank. The flywheel acts as the spacer to set correct depth. The E4OD flexplate spacer must be removed from the crank if this is the case.

 

I'll post a pic of my setup. the flexplate (or flywheel) from my c6 is much beefier than the thing on my e4od connected engine. Hence the reason why I started this post.

 

I have the heavy cast flexplate, with chewed up teeth, my ring gear is not welded and I can't find a replacement flexplate. Am I supposed to just change the ring gear like on the flywheel. It is the same size ring gear. 15.68 in. 155 tooth?