Pilot Bearing

Hi,
I am having trouble finding the correct pilot bearing for the V6 Dauntless engine with the T86A transmission. The bearing listed at O'Reilly and Dorman are the same part number, but the inside diameter is too small. That is to say, the T86 transmission shaft won't fit inside. I tried finding the part searching for the '67 CJ5 with the 3.7L, and I tried finding it using the Buick 225 odd-fire. Same part number came up for both searches.

Has anyone else had this same problem and if so, how did you solve it?

I thought about drilling it out and attempting to polish the inside of the bearing with my Dremel, but I would rather just find and use the correct part.

What say you?

 

Are you sure you have a T86?

 

I get a Jeep 3174730 for a T-86. This - https://www.summitracing.com/parts/cwa-j3174730

Is this what they are giving you?

 

I went thru this awhile ago, I had to resize the ID of the bushing to make it work.

 

Several forum members have hit this issue in the last couple of years. Many got as far as putting the transmission in (and pulling it into place with the bellhousing bolts) the only to have the "clutch not release" because the pilot bushing was fusing the crankshaft and transmission input shaft together.

It seems the only solution is reaming the new bushing to the proper ID like Jackdog did.

You definitely get used to modifying bad parts when working on these old Jeeps.

 

Maybe some advice about this from those with experience or knowledge would be useful? I recall the target clearance between bushing and pilot should be 0.005"?

Ideally I would expect to use a reamer, though a twist drill might be ok. These bushings are oilite, which is a bronze powder sintered together so they are porous. They are impregnated with oil. Usually there is a felt or foam disk (wick) behind the bearing in the pocket, that is saturated with oil. You could put the bearing in oil for a while, but I suspect not much will happen unless you evacuate the container.

Note some suppliers are replacing bronze with some kind of iron alloy? I expect it's ok, but it does not look like the older bearings.

Another option would be to measure your existing bearing and check for wear.

 

Use GM # 3752487
No need to team it.

 

Ken,

I was hoping you would join the conversation. Isn't this the same pilot bearing I bought on Ebay for you? If so, I found another one out there for $35.

 

Yes old pappy.
I wanted the OEM bushing because it’s the original non magnetic oilite bronze.
All oilite bushings currently being made contain iron and I don’t like that.

 

Sorry for the late reply. Yes, T86AA.

 

The wall of the bearing in the photo looks thin, but photos can be inaccurate. I don't see the OD or ID measurement on Summit's page. I am going to post below and share what I have learned. Thanks!

 

Interesting and good to know. Thank you!

 

Thanks. I looked up the GM part number and they don't provide the OD and ID measurements.

Edit addition: I found the measurements for GM part #3752487. They are 19/32" I.D. x 1 3/32" O.D. x 3/4".

Converting to decimals I get: 0.64 ID and 1.09375 OD. The outside diameter is too small for the opening in the crankshaft I have which is 1.195.

 

Oilite bushing/bearings. I always set the bushing in the palm of my hand and fill with oil. Place thumb over top and squeeze down very hard. You can see the oil ooze out through the pores. You know it's full.

 

Hi and thanks for your replies. I failed to remember that when I cracked my 225 odd fire open, I found that the crankshaft casting number was from a 1977 Buick 231. That may be why I am not finding the correct bearing/bushing via parts houses.

The T86 shaft is 0.63 in diameter. So I am looking for a bearing ID a bit larger than that. The OD of the bushing I removed (showed wear) is 1.195. I cannot measure the pilot bearing housing in the crankshaft because it's inset too far for my calipers to reach so I need to go by the bearing measurement. I am looking for something a few thousandths smaller than 1.195 because fit of the bearing OD was a tiny bit too tight. I couldn't pound it in far enough even after I froze it. So, "That boy ain't right."

The problem seems to be that a Buick even-fire 231 V6 was never mated with the T86 transmission, so I need to find a bearing by the dimensions that will work. It's frustrating to me because I rebuilt the transmission and the transfer case, which are ready to be installed. I also replaced the main and rod bearings as well as the rear main seal in the 225 so everything is ready to be monkeyed back into my little '67 CJ5, but I am dead in the water because of the elusive pilot bearing. DRAT! Double-DRAT!

 

.630 does not seem right I would expect it to be .625
Let me suggest the following AA part numbers.
Sorry I have no specs on the T86AA maindrive.
716170 = .590 I.D. X 1.090 O.D. for T90
716171 = .625 I.D. X 1.090 O.D. for T14
716158 = .670 I.D. X 1.090 O.D. for T18
716168 = .750 I.D. X 1.090 O.D. for T15

 

The J-series parts book calls for the same bushing for both the T-86 and T-14. This implies they are the same diameter pilot tip.

 

Right my cj parts books also indicate the same bushing as T14 with no change from 1966 through 1971.

 

The 77 crank could be an odd-fire crank. It was a mid-year change. I have an early '77 231 in my '69 that's an odd fire. If they swapped in an even fire crank, they would also have to swap the damper, flywheel, camshaft and distributor to make it run right. It's easy to tell an even fire crank because they have offset journals like this one from Scott's Jeep:


If the journals for the adjacent rods are shared like this one then it's an odd-fire:


All that said, I'm pretty sure both cranks take the same pilot bushing. Getting an OEM GM part like oldtime suggests might be a good option. Otherwise you'll need to resize the one you have to a few thousandths bigger than the input shaft.

Here's a bunch of previous threads where the pilot bushing was binding and need to be resized:

• Help Me Get My T18 Clutch Released!Did I Install My Clutch Disk Backwards?
• A Full Restoration Of My 1969 Cj5 With The Dauntless
• Never Doing Another Project !!
• New Clutch Not Releasing 1957 Fc150
• Clutch Pilot Bushing
• Cj5 V6 225 Clutch/pilot Bushing Headach,

 

I just double checked; the GM # 3752487 has a .590 I.D.
I find no other OEM GM pilot bearings for this crankshaft.
This implies that other transmissions than standard like a T18 or T15 will require aftermarket bushings such as McLeod .
In my case I like to bore the ID out of a used original bushing to fit the larger maindrives.