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Help with a 351w swap

2K views 14 replies 9 participants last post by  malarson 
#1 ·
Hello everyone, this is my first post so forgive me. But after months of stress and frustration, Ive broken down and come to a forum. I’m limited on my knowledge of engines and especially transmissions. Recently I swapped an 84 351w into my 68 coupe. It’s backed up to a c4 tranny. We bolted up the bell housing and trying to turn over the engine with a ratchet in order to bolt the flywheel to the torque converter, it won’t budge. It seems like I have tried everything to move it. I’ve had it in drive, neutral, and park. Still no luck. What am I doing wrong?

Thanks in advance
 
#3 ·
Many have difficulty in getting the torque converter to seat on the input shaft, it drops down turns and drops again I think. Some also have found they have the flex plate clocked incorrectly or flipped backwards. Sometimes best to take a step back, do something else for a a day or so, then look at it again, maybe with a friend.
 
#4 ·
The flex plate should be on the right way, since it would only fit one way on both the engine and TC. I have all the bell housing bolts in and have tried tightening, and un tightening the bolts, trying to turn the crank or TC. Is there any way to move the torque converter or flywheel and get it to seat?
 
#5 ·
What tranny did the 351W have behind it? If it was a manual- did you remember to pull out the pilot bearing in the end of the crankshaft? It sounds like you may have it bound up due to pressure on the torque converter.
 
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#6 ·
Most likely your gonna have to pull the engine back out so you can check the end of the crank to see if it has a bushing in it an verify the torque converter is seated in the pump. If it ends up being the torque converter I would pull the torque converter seal an look closely at the pump for any damage/cracks. If it was me I would pull the pump completely apart just to verify it wasn't broke or cracked.
 
#12 ·
Just to add a bit to this: When you spin the torque converter on the transmission, it has more than one "clunk" as different things engage. The shaft has to engage with the stator, and the stand-up ring thing on the torque converter itself has to engage with the pump. Just gently turn it as you push it back onto the transmission. I would also check it (and the face of the transmission) to make sure that nothing cracked, if the bolts for them both got tightened up while it wasn't properly seated. That will often break things.
 
#13 ·
Hi, as you assumed the motor was from an automatic car did you check the back of the crankshaft to see it it had a clutch pilot bearing installed. Was it hard to bolt the convertor onto the flex plate as the pilot bearing would prevent the convertor from sitting as far forward as it should and maybe push the convertor back onto the bell housing causing it to bind up.
good luck
 
#14 ·
Different Flex Plates

I am not sure if this applies but might help. When I replaced my C4 with an AOD from 1984 donor I had to purchase a new flex plate with 28 oz. weight for my 289. I had a similar problem as I drew the bell housing in with the bolts the converter to flex plate clearance disappeared and began to tighten where there was no “wiggle” in the converter to flex plate holes. I stopped and removed the trans and verified the converter seating to the pump more than once. I got the same results. I used a straight edge and a caliper to measure the depth of the flex plate and compared that with the depth the converter to the bell housing face. Parts man at Advance offered to order both flex plates available. I made the same measurement on the counter and got the correct flex plate. Ford made different depth or offset plates for different transmissions. It’s a little foggy now but I believe he said it was for a C6. Even the “Pro” at Dorman couldn’t tell me this and the plates from Advance were from Dorman.
Also I don’t think it matters if the pilot bearing is there or not.
Hope that helps.
 
#15 ·
Also make sure the drain plug on the converter is lined up with the hole in the flywheel, otherwise it will bind.
 
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