Archived 97 auto to g56 conversion gone awry

[Rick Harper]

Help me please!



Two weeks ago I took the auto out of my 97 turbo diesel and installed a 2006 G56. I installed a CON-O flywheel and clutch for the same model G56 from Southbend. I got the clutch assembly from Genos. The truck started and ran fine for about a week, then suddenly the starter bendix will not engage the flywheel. The shop I took the truck to has tried two more starters, and none will work. (He tried another '06, and an '08)



I got the transmission from Certified Auto recyclers out of Ardmore, Al. They origianlly sent me just the transmission. A few weeks after I got it, I was told by South bend that I would need the adapter that went with that transmission instead of the one that was on the truck. Certified sent me an adapter and starter that went with it.



It all seemed to go together very well and it worked fine for a week, but it is dead now. Anyone have a suggestion? Could Certified have sent me the wrong adapter? Could South Bend have sent me the wroing flywheel? Could aliens be altering mechanical physics because I am about to go on vacation??



Thanks for any ideas.

 

[GAmes]

The flywheel that came with my Southbend kit was different than a normal flywheel because the G56 is designed for use with a duel mass flywheel. I used my original starter that is used for a NV4500 configuration. I do no know if the starter for an automatic would be different. I didn't use or need any adapters. I have put nearly 45k miles on the G56 with no issues. In your case I would call Peter at Southbend for advice. I am sure he will want to know exactly which part numbers you used.

 

[Rick Harper]

Thanks GAmes, I took my 97 starter to the shop but it measured the same as the 06 and 08 we tried. He called to have a 97 for a manual sent over, and it is the same as the one from the auto truck.



He says it was slightly different, so he is going to put it in and try it, but even if it works, I fear it will be engaging the flywheel just enough to wear the edge down over time.



Any other ideas out there? Could I have the wrong clutch? I know the one I got from Southbend was real thick. Calling them now.



Good grief.

 

[ewcmr2]

The engine, SBC flywheel/clutch, and starter are all the same... Could the auto vs. manual engine adapter plate be different?



Like GAmes, my nv4500 to G56 swap didn't require and starter adapters.

 

[GAmes]

Could I have the wrong clutch?

Did you mean flywheel? That is what I am thinking.

 

[Rick Harper]

Yes, I meant flywheel.



The latest, South bend is telling me I need a starter from a 6. 7 truck, it has a 1/2" longer throw. The local dodge dealerships do not stock them, and do not have a picture, and will not order one without a VIN and money up front. Of course, my VIN will not help, and I want to see this thing before I buy it.



Also, the salvage yard is shipping me another adapter, that they are sure is out of the same model year truck as my G56, so I guess I will have to wait to get it and see if there is a difference.



Either way, I am screwed. I doubt I will have the part till at least next week when my wife and I were planning to tow our Cobra to the mountains for some great driving in the fall colors.

 

[ewcmr2]

Both dowel pins in place?

 

[GAmes]

The adapter must be wrong. You don't need a starter from a 6. 7 and I'm surprised anyone at SB would tell you that. You should be able to look at the adapter of any 5. 9 Cummins that has a 5 or 6 speed manual transmission bolted to it to see the difference with the one you have now. I'll be home in a few days. If you don't have the problem resolved by then I'll drop my starter and take some measurements.

 

[Rick Harper]

Thanks again guys.



Yes, both of the dowels are in place. There were no fitment issues at all.



Right now, I am in a holding pattern, waiting for the new adapter to arrive and praying that is the issue, even though it is going to cost a lot to have it intstalled.



Ricky

 

[Joseph Donnelly]

You need to do some measuring to see what you need. Here are some background facts:

1. All block plates (“adapters”) are the same up to 2002, and all space the 1994-02 starter correctly for the five speed flywheel's ring gear. To use the HO flywheel, you need a spacer that is about 0. 56” thick to space the starter toward the front of the truck and engage the teeth of the HO flywheel which are that much farther to the front.

2. 2003-2005 HO flywheels interchange with the earlier HO wheel. The block plate, however, was made thicker by . 56” at the starter mounting pad on HO stick shift engines, so no separate spacer is used. Automatic 2003-up block plates are thinner at the starter pocket.

3. The G56 wheel is spaced away from the crank, toward the rear of the truck, about ½” (I haven't measured it) compared to the earlier HO flywheel. See photos in TDR Issue 68, p. 88-89. That tells me the input shaft of the transmission is shorter than the older transmissions by that amount, since its “nose” meets a pilot bearing that is that same ½” or so distance farther back. This would be the reason you can't use an early HO flywheel with the G56 transmission. You cant use a 5 speed flywheel without getting it modified for the better 13” clutch bolt pattern.

4. Spacing the ring gear back that much means that you need either a different starter with more pinion gear travel to the rear of the truck, or a block plate mounting surface that is closer to the rear. It might be that not using the early HO 9/16” spacer with your 1997 block plate and starter will work out. The ring gear placement on the G56 conversion flywheel from South Bend seems to be the same as the early HO wheel when measured from the clutch mounting surface. That means the ring gear is mounted toward the rear of the truck that ½” or whatever amount the conversion flywheel's step is in thickness. You have to do some measuring. . .

 

[GAmes]

If I am following Joe correctly, and based on my install it seems that what you need is the block plate for a '97 manual trans (assuming the auto is different). I have a set of Larry B contacts to install in my starter, so I might as well do that and take some measurements while I'm in there.

 

[GAmes]

Because of the angle it looks longer on the ruler, but from the mounting face of the starter to the inside edge of the flywheel it is 1 15/16 inch. The block plate is 2 3/8 inch from the front of the transmission to the mounting face. As you can see, there is very little protrusion of the face from the block plate, maybe 1/16 inch.

 

[Joseph Donnelly]

GAmes, please reread #1 of my post above. All block plates up to 2002 are the same. that means stick and auto are the same. When the HO setup came out with the 13" clutch, Dodge used a . 56" thick spacer but continued with the same block plate. In 2003, Dodge went with two block plates. 2003 up plates have a different bolt pattern at the block with an o ring to seal the camshaft hole. Automatic plates have the traditional starter spacing, but HO stick plates have a thicker starter pad to take the place of the thin pad plus spacer that was used previously.

 

[GAmes]

Joe, I read it several times. Since you referenced the 5 speed I took it to mean that only the manual trans were the same. If the OP originally used the block plate from his '97 auto the only other thing that I could imagine is the flywheel he has is the wrong one.

 

[Joseph Donnelly]

OK. the auto and 5 speed flywheel have the same positioning of the ring gear and take the same block plate up to 2002. The HO flywheel used in 2000-2002 has a repositioned ring gear so a 13" clutch pattern can be drilled and tapped easily. That is why those HO engines use a . 56" spacer; the ring gear is that much farther to the front of the truck.

 

[Gene Heck]

Ring gear

Rick,



Did you check to see if the ring gear on the flywheel is loose? I have seen this happen before. When the ring gear is heated and dropped on the flywheel if it does not have a tight enough interference fit it will start slipping on the flywheel eventually. The flywheel has a shoulder that the ring gear mounts up against so that it can't move towards the trans and will stay relatively straight and in the right location on the flywheel but it will spin (slip) non the less. Since it worked for you for about a week and a couple of different starters didn't help I would suggest looking at that. See if you can get a long screwdriver or something that will engage the flywheel teeth and turn it and see what happens.



Gene

 

[Rick Harper]

Thank you everyone for all the ideas.



I am on vacation (borrowed a truck to get my car to the mountains) and will get a chance on Monday or Tuesday of next week to check all of the above. I will post the findings.



Thank you again, this is a good forum powered by great people.



God bless



Ricky

 

[Rick Harper]

For anyone following this. I am still waiting. The new adapter came last week, but the garage I have the truck at has not had time to put it on the rack and check it out.

 

[Rick Harper]

Update! auto to g56 swap in a 97

Just heard from the shop that has my truck. The second adapter appears to be thinner, and as such should solve this problem. That is great news! Clearly there are some differences in the adapters.



Now, do you think I will have any success getting the vendor that sent me the wrong adapter covering the bill I will be getting in a few days?



Thank you for all the help, and God bless,



Ricky

 

[GAmes]

The second adapter appears to be thinner... ... .

Did you use the measurements I gave you, or pass them on to the mechanic?