1977 400 original bore

[Boise68]

I picked up this 400 last weekend, with the option of another if the block is not salvageable. It was stored inside for the last 20 years and still had oil on the cam and lifters beneath all the dust.


First surprise came when I tried to loosen the crank bolt to remove the damper. The fella I bought the short block from thought it was froze. Not. :hello2::hello2:
The crank turned easily, the bore checked out to stock bore too. There's a ridge at the top of bore but without a bore dial indicator I am not sure of the actual wear. Any recommends on a bore dial guage?


The second surprise was the double timing chain set. Did all 400's come with double timing chains? I've read that some police and hp 400's came with this option? I am going to remove the rotating assembly this evening and get the first look inside. Any watch-outs or suggestions? Thanks ahead all, :nike:

 

[WP29440SE]

not bad for 40 bucks lol , I would lube/clean up the cylinder walls before you start taking the pistons and rods out. other than that, tear into it

 

[tallhair]

Looks like a great buy and best wishes on it turning out well

 

[Meep-Meep]

I've seen a motorhome engine that came with a double roller but not sure about 400's. The era seems right so I guess it's possible as a HD application.

Yep, mix up a batch of acetone and ATF (50/50) and pour it around the rings to loosen them up. You can use a snap gauge to check bore wear but some finesse will be required to get accurate readings. I have successfully honed and re-ringed up to .005" taper. Small witness marks are OK but it all depends on what you are trying to get out of it.

 

[bm02tj]

that has an after market cam gear so not stock

 

[Boise68]

Thanks Meep, I am heading out to mix up the ATF and tone. My interest in bore measurements is to really see where the block is, not sure what direction for the build. I would think if someone took the trouble to put in an aftermarket timing chain they were probably interested in 'pushing the engine'. Let the adventure begin.

I've seen a motorhome engine that came with a double roller but not sure about 400's. The era seems right so I guess it's possible as a HD application.

Yep, mix up a batch of acetone and ATF (50/50) and pour it around the rings to loosen them up. You can use a snap gauge to check bore wear but some finesse will be required to get accurate readings. I have successfully honed and re-ringed up to .005" taper. Small witness marks are OK but it all depends on what you are trying to get out of it.

- - - Updated - - -

Thanks bm, From what I can find, it is probably a Cloyes, given the S380 numbers, etc. Not sure how to identify the cam, doesn't seem to have any identifying marks, numbers.

 

[Boise68]

400 block disassembly goes well

There were no broken rods or scored cranks and the block initially cleaned up well. It is currently being magnufluxed and then sonic checked.
Just a few pics, I know the 8T400 indicates the block was assembled in 1978, but what is the the significance of the '6s'?





If the block checks out good, I'll hit you guys up for some build advice. Plan A is a stock 400 build: "Hemi power for half the price".

 

[Meep-Meep]

Looks good from here. How did the ATF / acetone work out?

Just be thankful you don't have three six's.

 

[Boise68]

Thanks Meep, boy never thought about the 3 sixes. Yikes!

The ATF solution penetrated great, nothing was 'froze' and everything came apart easily. I am gonna drop by the machinists today. ;)

 

[Meep-Meep]

Cool!

We're here to help when you start planning the build.