Novak Adapter - clutch disasters

Dear Jeepers,

I am nearing the end of my rope. Here's the long sad story:

The vehicle: 1972 CJ5 - 304/3speed/Dana 20

The project: Tranny swap - install rebuilt SM420.

Background: I horsetraded with my brother for a rebuilt (Herm) SM420 with a D18 adapter (advance). New in the box. It was my brother's, but has been sitting unopened in my garage for 3-4 years. I knew it was set up for a small hole D18, so I called Herm and he set me up with the large hole/D20 part for the adapter.

Then I called Novak and ordered their SM420 to AMC engine "Master Kit." The principal components of the kit are a new front bearing retainer for the SM420, a new cast bellhousing, a clutch release arm, pilot bearing, and various small parts.

WEEKEND 1 (May 22):

The day came when all the parts were together. Novak's instructions said I needed a clutch disk and throwout bearing for an '81-'86 CJ (V8 or I6). Both of these were purchased locally. We got everything torn apart and started assembling the new package.

The tranny to transfer case went smoothly. The advance adapters parts all fit perfectly and it was about a 20-30 minute job to assemble the tranny/adapter/transfer case combo.

Then the problems started . . .

The beautifully machined, painfully pretty front bearing retainer from Novak would not bolt to the front of the SM420. The holes would line up well enough to start the bolts but were off just enough that you couldn't tighten everything down. All of the work is weekend work, so we couldn't contact Novak until Monday.

Monday I called Eric at Novak. I dealt with him 10 or so years ago when I was installing one of their NP435-D300 adapters and it was frankly his helpfulness and great service then that convinced me to use Novak for this project. Eric was mystified at my problem, but said he would grab the part off the shelf and go try it on some SM420's they had in the shop and call me back. Two hours later Eric called me back and said that they were able to get the retainer he had on all the trannies they tried, but that there was considerable variation in the spacing of the bolt holes. He told me they would open up their pattern on the next production run, but that would be a few weeks out. He suggested drilling out the holes a little larger and seeing if we could get it to go all the way down that way.

WEEKEND 2 (May 29):

We spent 2 hours drilling holes and using a dremel and an angle grinder to open up the countersunk holes on the input bearing retainer and finally got in to go onto the tranny. Thinking that all was well, we put the bellhousing on and tried to assemble the clutch parts. The new disk went in as it should, as did the pilot bushing. The first problem came when we tried to assemble the clutch release arm onto the pivot. There was no where to attach the spring. The arm seemed to have the holes, but the ledge that the 72 used was not present in the conversion bellhousing. We scratched out heads for quite a while and finally tried drilling a hole in the pivot post to anchor the other end of the spring. It was jury rigged and I didn't like how it looked, but its what we had so we went with it.
We put everything back in the Jeep and the clutch would not disengage. The new clutch release arm was bottoming out on the bellhousing before the throwout bearing was making contact with the clutch fingers. I checked the part number on the throwout bearing and it looked to be an AMC part but not a Jeep part. (Timken #614038 instead of #614115) I was suspicious of the bearing and out of time. One more weekend gone. THis was Memorial day weekend, so I couldn't call Eric until Tuesday after Memorial Day.

Tuesday June 1, I called Eric again and he suggested a longer throwout bearing. He gave me a part number, but I had bad luck finding the right parts here in Atlanta, so I asked if he could send me one. Eric offered to send it. The challenge was getting it from Utah to Georgia before the weekend. Eric and I discussed shipping options at length, and settled on shipping that would cost me a little extra but would make it as long as his courier arrived with the throwout bearing before 2:00. I went ahead and ordered a twin stick shifter for my transfer case while I was at it, and Eric threw in a shifter knob for the SM420.

While on the phone with Eric I asked him about anchoring the spring. He said there should be a groove cut in the hole where the bearing retainer comes through the back of the bellhousing. I knew that we hadn't seen the groove, but he sent me a picture of it. It would be easier to fix it with a grinder than it would be to mess with shipping the bellhousing and much faster, so I decided we would just fix it on site.

Two days later I got a call from Ken at Novak with a question about the twin stick kit. They were out of stock on the twin stick kit and had held the order. I told Ken how disappointed I was that they had held the order, cancelled the twin stick, and asked him to please go a ahead and ship the parts. One more week gone.

WEEKEND 3 (June 5): No parts = no work. But I still got charged for the expedited shipping.

WEEKEND 4 (June 12): Parts in hand, we pulled the transmission out of the Jeep. The throwout bearing Eric sent me would not fit in the clutch release arm Eric sent me. I didn't know which part was wrong, but these two parts were obviously not made to go together. Not having anything better to do, we ground the arm to make it fit, ground the groove for the spring into the bellhousing, and installed it anyway. We still couldn't get it to work. It was a much longer bearing, and appeared to be making contact, but without driveshafts in, we couldn't get tension off the yokes by depressing the clutch pedal. Thinking that we were stumped again, we folded our tents and waited to call Eric on Monday.

WEEKEND 5 (June 19): Called Eric again on Monday June 14. Sent him pictures of the bellhousing, and release arm/bearing. Eric said that his parts supplier had given him the wrong bearing. He offered to send me another one. He would have to order it and he wasn't sure on the time frame.
I talked to him again later that week. He still hadn't received the bearing. He had given me the part number and my local guy didn't have it either. So I talked theory with him. IF the bellhousing was supposed to emulate an '81-'86 CJ then shouldn't any complete set (disk/pressure plate/bearing) for an 81-86 CJ work? He said that it should, and we theorized that maybe I had a mismatch between my pressure plate and the bearings we were trying. So I told him to hold off on the bearing and just ordered a complete clutch kit locally. (this was getting expensive).

Weekend five (June 19) we put in the complete clutch kit. Now everything between the flywheel and the transmission is either a kit for an '81-86 CJ or a Novak part. We couldn't help but notice that the new bearing, pressure plate, and disk looked exactly like the ones that did not work on Weekend number 2. We installed the tranny anyway and got the predictable results. The bearing was not reaching the fingers on the pressure plate. (By this point we are getting pretty fast at removing and replacing the tranny - about a 45 minute job without driveshafts and cover plates). Since we had nothing better to do, we tried the old bearing (that Eric said was the wrong part number) again. We actually got a Jeep that would move under its own power. With the tension of the driveshafts on the tranny, we were able to get the Jeep in and out of gear. The problem ended up being the other extreme. The longer bearing was too long and the clutch was partially disengaged all the time. It slipped badly in third gear. I figured if this one was close, but too long, then maybe the part Eric tried to send me would do the trick. So I called around some more and found that NAPA could get me the part number Eric had given me for the bearing that should have been sent on Week 3.

WEEKEND 6 (today June 26)

I went to NAPA and picked up the bearing. It was incorrect. The bearing they gave me was a "groove type" throwout bearing instead of a "plate type" throwout bearing and would not function with the release arm from Novak. I don't know if Eric gave me a bad part number(Timken #RB-01658-C), or if NAPA's interchange messed it up. Either way, this bearing is not going to work. The bearing NAPA had for me was not a Timken it was a different brand (PN N1701), but NAPA's computer showed it as interchangeable.

To date Novak has sent me an SM420 input bearing retainer that would not fit an SM420, a bellhousing that was cast incorrectly, a throwout bearing that would not fit their release arm, and given me a part number for another throwout bearing that also won't fit their clutch release arm. I have bought a clutch disk ($80), a three throwout bearings ($26, $80, and about $40), a complete clutch kit ($162), and invested six weekends on what should have been a one day job. Eric tells me that they have sold "thousands" of these, and never had this kind of problem.

Advance Adapters sells a similar kit that their instructions mention will only work with "thin" flywheels (less than 1" thick), Novak doesn't mention this. My flywheel seems to be thicker than that (about 1.5") , but logically, that would only make the bearing make contact sooner. My kit won't make contact at all. AA also specifies a diaphram type clutch with their kit, all of the ones I have been dealing with are Borg & Beck type. I was concerned about that, but figured that a complete kit would eliminate this as an issue.

Any Suggestions?

 

Almost sounds like you should have gone with the one for thinner clutch plates.:?

 

I have been using the clutch disk that came with the clutch kit. It is identical to the first one I bought (same part number stamped on it). Its so thin already I don't see how it could make a difference. My confusion is how they could have sold "thousands" of these and never had a problem. If that is true, then either I am doing something terribly wrong, or this one bellhousing is the wrong depth. I don't know. . . I am calling Novak again today.

 

man, sorry to hear about this. i had a terrible problem with mixing and matching clutch parts for my 225v6, ford t18a, and dana 18. The novak slave cylinder wouldn't work with the manifolds, the mounting bracket didn't clear the alignment dowel pins, etc. None of the TO bearings would work, and actually, I had the same problem with the TO bearing not fitting the fork. It was a pita.


I battled for weeks and I still don't think it was ever right. This is why I tore the whole thing apart and started my build.

Good luck and let us know some good P/Ns if you figure it out.

 

Dang, I have similar Novak parts in my garage waiting to get installed. I'm losing interest fast after reading this thread.

 

Wow!:?
I can't even think of anything you missed or messed up.
What a freakin bummer.
Prehaps take a HUGE step back and pull it out, (yet again).
Put all the parts on the floor, maybe either take a pic of them with dim. and send it to Novak.
Or, take to them and send ALL of it back and let them match part for part.
Maybe whilist it's out, kinda assemble it all up and this way You can lookie see, what's what.
Flywheel flush with bellhousing with the clutch/pressure plate on, trans/bell housing on with throwout bearing, get a measurement, see how it all works.
Sounds like your bell housing is too long??, you throw out bearing too far away in the "rest" position to reach your clutch pressure plate.
Input shaft of the trans too long-naaa, then the trans wouldn't bolt to the bell housing.
Gotta be in the bell housing-something.....
Wow! I dunno.
Joe
Makes you think, "What was I thinking"!

 

Talked to Ken Olsen today at Novak. He is sending me another throwout bearing. It sounds like the one NAPA gave me was the wrong part. I'll post more when the UPS guy gets here.

 

Holy s_ _t. This is so far above my pay grade I don't think I'll ever yank out my T90 for a 4 speed.

 

Update:

1. The Jeep is up and running.

2. The Throwout bearing that Ken sent me was the same incorrect bearing that Eric had sent me earlier. Once again Novak=No-go.

3. After seven weeks of wrong parts/part numbers/and willing but completely ineffective assistance from Novak, we decided to fabricate a throwout bearing from two of the four that I have bought during this ordeal.

4. We added a spacer and a second plate to one of the plate style bearings I had already bought and effectively lengthened it to about half way between the two bearings that Novak recommended/sent. A couple hours of grinding, welding, and measuring and we had a bearing that worked.

5. Jeep now drives like it should. I'll post pictures and measurements for the fabricated bearing when I figure out how to post pictures.

6. Bottom line: Don't attempt this conversion with the Novak kit unless you are OK with fixing all the bad parts they send you and then making your own throwout bearing.

Jon

 

Man sorry to here this, I have used many Novak parts and have had nothing but great luck. I do have to say that I do a ton of research before I order anything so I know what I am supposed to be getting.
SO I am just wondering? The bell housing you got. is a T176 housing and a adapter from the housing to the tranny?

 

I'm SOOOO glad to hear you got it straighten out!
It's sweeter when it finally DOES work!
I gotta give you two thumbs up for clamping onto the project and not giving up.
A mere mortal man would have toss in the wrench and gone back to stock!
My greasey hat is off to ya!
Joe
It's jeep, your foot is SUPPOSED to be wet when it rains!

 

always sad to read about stuff like this
you would think the manufacturer would have all the engineering done before production
or at least have a mock set-up to try it all before manufacturing
shrug::::
I always hate to hear the line about "selling thousands and have never had a problem".
I know Novak has had their problems and lost a few customers due to quality control issues...long time 30 year customers
anyway, gald you got it figured out and it's all working now.

 

It sounds like the problem could have orriginated from the pivot point. I have seen pivot balls that were screw in type that were several different lengths making the proper length throw-out bearing very difficult to find.

 

I don't think it was the pivot point unless it was cast incorrectly. The pivot in these bellhousings is a cast pedestal with a ball in a socket at the top.

My brother thinks it was the clutch release arm supplied by Novak. They insist that it is a stock Jeep part, but it absolutely will not fit around the "jeep" throwout bearings that Novak sent me.

The most frustrating part of the process was that Novak kept insisting that their kit exactly emulated an '81-'86 CJ, but couldn't explain why '81-'86 CJ clutch components were not working. Advance Adapters says there are two possible flywheel thicknesses. That would cause the problems I was seeing, and explain why Jeep has a long and a short bearing. But we tried both and neither bearing worked. If Novak has truly sold "thousands" of these things, then you would think they could have come up with a solution in seven weeks of trying.

 

it's true that 1981 and later CJs, 304 or 258, use the same throw out fork and throw out bearing; there is only one application for those years for both the fork and the bearing.
I'll give you the factory numbers, might save someone a headache in the future.
these are Jeep part numbers:
T/O Fork: J5361620
T/O Bearing: J5361610
4 cyls use different components.
Keep in mind some of their stuff might be coming from Crown or another supplier.
Wouldn't be the first time parts have been wrong.....
I have no knowledge of Novaks supplier, so I'm not bashing Novak here.