I just got done swapping in a C6 (professionally rebuilt) in place of my NP435. When I got all the fluids filled and started it up, there was a terrible grinding sound. It sounds like the flexplate is hitting the starter (New NAPA starter). The C6 & flexplate came out of a 4x4 with a 400 (I pulled it myself), so I know that is correct.

Has anyone else had this kind of problem?


Ryan
'78 F250 Ranger Supercab 4x4
400, 4spd (460 & auto soon)
Dana 44/60 F&R, 4:10's, 33's
Dark Chocolate Brown

 

You sure the notches in the converter dropped all the way into the front pump on the transmission?

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94 E-150 Mark III High Top Conversion Van 4.9/C-6
89 Mustang LX 5.0 - 5 speed - Original owner

 

Yeah, I put the converter in the tranny and then loaded the tranny onto the engine. The tranny slipped up next to the block by just pushing, I didn't have to use the bolts to pull the tranny to the block. I would imagine that if the converter was not in all the way, then it would create a bind.........?

Thanks, though......


Ryan
'78 F250 Ranger Supercab 4x4
400, 4spd (460 & auto soon)
Dana 44/60 F&R, 4:10's, 33's
Dark Chocolate Brown

 

I am not sure about the 351M/400, but on the FE's, there is a steel plate that goes between engine and tranny. If it was missing, the starter may contact the flexplate. Does it grind if you turn the engine by hand? If so, remove starter and see if it still grinds by hand. This will help narrow down the possibilities.

 

Apparently this steel plate was left out when I had my engine rebuilt. The guy put my starter in with 3 washers as spacers. I cut a piece of steel to match the opening and now I use that as a spacer. It is easier to put in than the washers, and it keeps dirt out. Eventually, I'll fix it the right way, but I've put 50k on my engine this way.

Matt

 

Well I found out what it was. I'm kind of embarrassed I didn't think of this first. I used too long of screws to put the small inspection plate on the opening at the bottom of the bellhousing and the ends of the screws were rubbing on the flexplate.

Easy fix. I started it up, and everything works fine........!!


Ryan
'78 F250 Ranger Supercab 4x4
400, 4spd (460 & auto soon)
Dana 44/60 F&R, 4:10's, 33's
Dark Chocolate Brown