FOUND my 400sbc

Status
Not open for further replies.

Jbug.jbone

Apprentice
Jan 6, 2020
63
32
18
Just picked up this chevy 400sbc. Previous owner said it came out of a RV with 70k on it. .020 decked head, double coil valve springs, weiand intake, came a few extra parts. Motors been sitting sometime. What do you all recommend I do to get her back on the road? How would I go about cleaning the heads? Previous owner said I should clean those with diesel, he said to pour a little trans oil into each each cylinder before cranking her over. I might drop the oil pain to check out how the bottom looks.
 

Attachments

  • D01DA5B5-2C6D-461B-9A15-EC137F8B5F23.jpeg
    D01DA5B5-2C6D-461B-9A15-EC137F8B5F23.jpeg
    188.8 KB · Views: 96
  • 955E5419-26DB-4A9C-B789-92191521F2CC.jpeg
    955E5419-26DB-4A9C-B789-92191521F2CC.jpeg
    212.8 KB · Views: 101
  • 4B94B965-C360-41CF-9583-E4BE2242802E.jpeg
    4B94B965-C360-41CF-9583-E4BE2242802E.jpeg
    179.2 KB · Views: 100

Streetbu

Know it all, that doesn't
Supporting Member
May 22, 2011
3,729
11,562
113
Central NY
I would at least borescope the cylinders at a minimum, if not pull the heads.
 
  • Like
Reactions: 4 users

64nailhead

Goat Herder
Dec 1, 2014
5,691
1
12,145
113
Upstate NY
Agreed. Head gaskets and intake gaskets are cheap.

Is it safe to assume that it turns over by hand?
 
  • Like
Reactions: 4 users

ELCAM

Royal Smart Person
Jun 19, 2021
1,120
1,263
113
70K miles in a motor home might be way more wear than 70K miles in a passenger car.

I would pull the heads disassemble them and clean everything with a wire brush put everything back where it came from do not move the parts around. Drivers side head has a broken exhaust manifold bolt. Check valve guide to stem clearances and install new seals and reassemble after soaking everything in oil.

Make sure the block is covered and far away from the wire brushing. Remove the balancer and clean and inspect the rubber in it. Pull the pan and inspect all bearing clearances lubricate on reassembly, replace front and rear seal and oil pump. Replace timing set and replace all gaskets. Pull and inspect the lifters if ok then submerge in oil and pump them up with a pushrod. Don't move the parts around everything back where it came from.

Chase all threads exposed to the weather, ex manifold, bellhousing and accessory mounting holes etc. (anywhere the bolt was missing when in storage) use lots of oil.
 
  • Like
  • Agree
  • Friendly
Reactions: 11 users

DRIVEN

Geezer
Apr 25, 2009
8,072
14,520
113
*CENSORED*
Looks like a mostly complete core. Did the seller say why the rockers and pushrods were removed?
 
  • Agree
Reactions: 1 user

scoti

Royal Smart Person
Sep 5, 2019
1,970
3,382
113
Texas
That also looks like an old single plane aluminum intake on top of those heads..... Definitely something a 'motor-home/RV' would not have. I would take the path of everything is an unknown since an RV based 400 would of had a cast iron dual plane intake.

What casting number is on the heads (both/each)?
 
  • Like
  • Agree
Reactions: 4 users

Jbug.jbone

Apprentice
Jan 6, 2020
63
32
18
Agreed. Head gaskets and intake gaskets are cheap.

Is it safe to assume that it turns over by hand?
Alrighty so say I take the heads off do they have to go to the machine shop? I wanted to stay away from the machine shops since they’re backed up for months in my area.
But yessir turns over by hand.

Looks like a mostly complete core. Did the seller say why the rockers and pushrods were removed?

He did not mention why they were pulled out actually I’ll have to ask him.

I would at least borescope the cylinders at a minimum, if not pull the heads.

Gotcha! I’m thinking about pulling the heads to change the gaskets. But I think I’ve heard that soon as you pull the heads they have to go to the machine shop correct? I wanted to try to stay away from that since in my area they’re backed up for months.


That also looks like an old single plane aluminum intake on top of those heads..... Definitely something a 'motor-home/RV' would not have. I would take the path of everything is an unknown since an RV based 400 would of had a cast iron dual plane intake.

What casting number is on the heads (both/each)?

Correct the motor came with a weiand brand, “X-celerator” single plane aftermarket intake manifold. Casting number on the heads are
462624. From what I’ve read they’re basically boat anchors.
 

Attachments

  • F432833C-0729-4681-B31A-EDAA3D5D8AE6.jpeg
    F432833C-0729-4681-B31A-EDAA3D5D8AE6.jpeg
    248.1 KB · Views: 85
  • 8B09F095-8E39-4D4F-A547-824C01619200.jpeg
    8B09F095-8E39-4D4F-A547-824C01619200.jpeg
    198.2 KB · Views: 76
  • Like
Reactions: 1 user

Jbug.jbone

Apprentice
Jan 6, 2020
63
32
18
Still trynna get the hang of this website, still trynna get used to replying to everyone on one message. “Quoting” the messages seems to help out l, instead of hitting the reply button for everyone
 
  • Like
Reactions: 1 user

Streetbu

Know it all, that doesn't
Supporting Member
May 22, 2011
3,729
11,562
113
Central NY
Alrighty so say I take the heads off do they have to go to the machine shop? I wanted to stay away from the machine shops since they’re backed up for months in my area.
But yessir turns over by hand.



He did not mention why they were pulled out actually I’ll have to ask him.



Gotcha! I’m thinking about pulling the heads to change the gaskets. But I think I’ve heard that soon as you pull the heads they have to go to the machine shop correct? I wanted to try to stay away from that since in my area they’re backed up for months.




Correct the motor came with a weiand brand, “X-celerator” single plane aftermarket intake manifold. Casting number on the heads are
462624. From what I’ve read they’re basically boat anchors.
No, heads don't have to go to the machine shop if you merely remove them. Unless of course you find something wrong while they are off.
 
  • Agree
Reactions: 1 users

Jbug.jbone

Apprentice
Jan 6, 2020
63
32
18
No, heads don't have to go to the machine shop if you merely remove them. Unless of course you find something wrong while they are off.
Gotcha! I just did a quick Google search of the casting numbers 462624, from what I’ve read they’re basically boat anchors
 
  • Like
Reactions: 1 user
Status
Not open for further replies.

GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.

Please support GBodyForum Sponsors

Classic Truck Consoles Dixie Restoration Depot UMI Performance

Contact [email protected] for info on becoming a sponsor