Lugging at speed/No power at WOT

[ratdude747]

Of course I'm replacing the valve seals.... they were toast. And come in the gasket set. The valves didn't have much of any play in the guides. Still nice and tight (but smooth, not dragging).

Didn't know that hot tanking would effect plain babbit bearings... Didn't think hot tanks got that hot.  Edit- I'm an idiot. Looked it up, I see. It's the caustic cleaner, not the temperature that causes the issue. I'll have him put in a set of stock sized bearings. Or bring in the cam and have him verify the tolerances.

[Gary Lewis]

Yes, you beat me to it.  The solution eats the bearings up.

And yes, it costs money to rebuild an engine.  

Anyway, glad the guides are good and that you have the seals.

[ratdude747]

*Will have the seals. Had to return the gasket kit as it was part of the re-ring kit I bought and had to return (contained rings and main/rod bearings). Rockauto obviously doesn't allow for partial returns for store credit, so I had to return the whole set. Once I have sizes, I'll re-order.

[ArdWrknTrk]

I didn't realize a machine shop would bore to X.

All the guys I use will clean up, get parts in hand, and then machine to final tolerance.
Even if I told Mike "I'm going .060 over" or "-010 on the crank" he'd want those parts in his hands before making chips.
(And with good reason!)

[ratdude747]

It's a chicken and egg sort of problem. We don't know how much it will take to clean up (I'm thinking 0.030" will get it), so I can't order parts until I have a confirmed measurement. Same for the crank- he's going to clean it up, and report back if it's in spec (and if not, how much re-grind will be needed).

He'll be getting the pistons to swap the rods over, so piston size will be verified.

[ArdWrknTrk]

Yup, this is why quality machine work (and especially engine building) is expensive.
Check, and recheck...

Crack check
Clean up the bores
Square deck to crank
Sonic check the cylinder walls
Install cam bearings
Recondition rods
Order pistions/rings/bearings
Confirm sizes
Cut/grind/hone to spec.
Gap rings
Assemble rotating assembly
Build up short block: crank, cam, timing set
Crack check and deck heads
Install guides and ream
Porting... if desired
Clean the head... again
Cut seats
Install valves and lap
Check installed height of springs
Cut or shim to height/pressure
Install heads
Check pushrod length
Order pushrods
Install valve train
Double check piston to valve clearance and squish
Install pumps and tin
Install manifolds

NOW you're close to installing it into something, adding front dress and fuel, wiring it up and priming it for break-in.

[ratdude747]

Heard from the machinist the other day and ordered parts. Needed bored 0.030" over, crank was in spec (no regrind and/or undersize bearings needed).

Parts should be here Friday, so with any luck I'll have her on the road within the next two weeks. Maybe.

[Frank Wyatt]

Good to hear it's coming along. The 300 is a great engine in a truck and I love mine in my truck.

[ratdude747]

 A minor setback may be coming... work is re-mobilizing me next week... at least it's a fixed 8.5-9 hours, so I'll have some time.

Anyway...

[ratdude747]

Having issues with installing the new timing cover crank seal.

Old one was in TIGHT... had to partially cut it with a hack saw to allow it to crush and hammer out.

The new one I ordered as an NOS is older than expected... while the baggie has a new-ish dealer sticker, the bag itself is very old with a copyright of 1966 . The part is more of a muesem piece than something I want to use.

Luckily, the gasket kit, despite the notes saying it had no crank or valve seals, came with all of the above. However, the timing seal in question is too big... cannot get it to start straight in the hole with a seal driver. Maybe 5-10 thousanths oversized relative to my timing cover bore. Is this normal (and I'm doing something wrong), or do I need to get another seal?  

Yes, I did lightly heat the cover with a torch... but not much since I don't want to warp or melt the aluminum.

[Gary Lewis]

I wish I knew the answer to your question.  But at least you have the seal.

Hopefully someone will come along that knows the answer.

[ratdude747]

Bought a new seal at autozone. Fit in no problem (still a very tight press fit though!). Seems the one in the kit is out of spec... :(

[Gary Lewis]

Good!  It is bad to have a bad seal 'cause it makes you question everything, but at least you got the problem solved and can move on.

[ratdude747]

Got the goods back from the machinist... $325 later, and we're on to paint and assembly.

Paint is complete. I'll post pics later.

Run into an assembly issue: I'm an idiot and bought the wrong plastigauge. Was going to post about my bearings being too tight, but I misread the spec and goofed. Will get the right stuff tomorrow. DOH!!!

[Gary Lewis]

I love it when a plan comes together!  And it is still progress when you take two steps forward and one back.  

[ratdude747]

At least on #1 (all 7 mains had the same result with the "wrong" plastigauge), it looks like I'm at between 0.0020 and 0.0030 (more towards 0.0020). Out of the desired range (0.0008-0.0015), but within the allowable  range (0.0010-0.0028)

Not enough to warrant going down a bearing size, but OK to run? Or do I need to get a re-grind?

[ArdWrknTrk]

You're rebuilding your engine now.
Do you really want to start with your clearance at more than double the desirable  starting clearance?
You may have another 8/10, but that's less than half the allowable wear.

Replacing the mains is another engine out operation.

[Gary Lewis]

Man, that's a good question.

Remind me, this is a re-bored engine with new pistons, rings, etc?

And what was done to the crank?

I want to have the info in one place before trying to suggest what to do.  And I'm sure it'll help the others to reply as well.

[ratdude747]

Rebored/honed block. Crank was polished and I was told by the machinist that it was "in spec" and to use standard sized bearings. The bearings are NOS ACL's (1994 MFD).

....

Spoke with a buddy who does Z-car restorations as a part time job... he says it should be OK, since it's the mains and not the rods (and it's within the acceptable range).

[Frank Wyatt]

I would believe that it would be OK. However, I would get an experts opinion and go however they suggested. You do only want to do this once and right the first time around.