Inspection plate touches the flex plate?

[kairo1]

When I drive I hear a rattle thought it was an exhaust leak. Further inspection I noticed one of the bolts on the lower side of the inspection plate was backed off. With the motor running I pushed the inspection plate to tighten the bolt. However, when doing this the inspection plate touches the flex plate. How is the possible? )Recall my previous post about the 401 was rebuilt by the dealer that could not fix the rear main seal!)

[mwood65]

Could the flex plate be on backwards? I am sure it is offset one way or the other and maybe it's on wrong???

[68glad]

Are they the original bolts? The flexplate bolts have a thin head. A regular size bolt head will hit if i remember correct.

[kairo1]

Rear Main SealUpdate 1991 Grand Wagoneer w/401

Okay. Been a while since I posted the status of my rear main seal. So, the 401 ran flawless, no leaks, oil pressure above 55lbs while driving; 40lbs at idle.
I attached my 3,660 lbs 1969 Airstream to the GW last week. Accelerating I heard the inspection plate noise as it touched the crankshaft. Only on accelerating was the noise audible. If I let off the gas, the noise disappeared. Arrive at my destination. Looked under the GW no oil leaks. Hmmm. I unhooked the AS, drove back to Vermont 149 miles. Oil pressure dropped below 40 lbs driving; nearly 10lbs at idle. Arrived home. Looked under the GW. Oil was literally running out of the engine...Rear main seal failure. The top of the inspection plate has crankshaft groves, burn marks from where it rubbed the crankshaft and bit of rubber on the edge. HMMM!

Recall until I attached the Airstream the GW operated perfect. Prior to last weeks trip, I drove the GW without the Airstream to Bangor, Maine like a wild man to find any issues. NONE! So, the 401 will removed on Tuesday. I'll take the long block to RPM Performance Racing Engines in Georgia, Vermont. Finally I'll know what the cause of the rear main seal failure.

My thought is torque converter is not freely moving on the shaft, pulling the crankshaft back toward the inspection plate with the load of the Airstream?

[Ristow]

Thrust bearing and surface of the crank is gone. Get the crank welded and reground and replace the torque converter.

[kairo1]

Rear Main SealUpdate 1991 Grand Wagoneer w/401

Ristow,

Which torque converter do you recommend for the 401 to 727?

[Ristow]

transtar reman. i run the factory hi stall unit,about 400 rpm over the lo stall jeep used oem. cr54h is the number....but call and verify that.

[SOLSAKS]

kairo1

a wagoneer wit an airstream ?

man I bet that gets some looks from other motorists !

you prob already have before

but please post a photo of the wagoneer with airstream for us to enjoy !

dave in NC

[kairo1]

Rear Main SealUpdate 1991 Grand Wagoneer w/401

Ristow,

My plan is:

1. Take the 401 long block with flexplate and harmonic balancer to RPM Racing engines to do whatever it takes to fix my recurring rear main seal issue; External balance as well.

2. Install the original 727 which functions properly. I'll remove the new large oil pan from the 727 currently installed place it on the original 727. I had the replacement 727 rebuilt by some racing guy in Massachusetts. Maybe he messed up. I did not like the "hard shifting" in between gears when I stomped the gas pedal anyway. LOL. So, back to the original 727. Other than replace the two seals and install a new torque converter, what tasks should the transmission company perform on my original 727? The original 727 functions normally has 72,000 miles on it.

[Gadzooks2]

There is a chance the flex plate itself is cracked. If so it may not show up unless under heavy load like towing, then it may move enough to rub..