Breathing new life into the 318 in the Scamp!

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Got the heads pulled. I still don't know what's up with them, until I check them. I'll likely have them milled, which is going in the tighter direction. It's already at 9.75:1 static. I may ditch the .028's and go with something bigger, depending on how much needs trimmed.

I guess I'll be waiting until I get them back, check CC again and buy gaskets after I know my numbers. Don charges $60 for milling on both heads. Not too bad, if that's the route I go. I have no idea on gaskets just yet. 3rd time's a charm on those.

4:30pm -

Scamp%20Engine%20before%20teardown.jpeg


6pm -

Scamp%20Engine%20after%20teardown.jpeg


Frowny face.
 
It was leaking at the water passage, at the gasket itself. It should have more than sealed. I did use black silicone sealant on the intake bolts, as well as the timing cover and water pump. I used teflon on the exhaust bolt that replaced the rear stud on the left side.

Everywhere else, except for the left head gasket sealed at 12psi when I hit it with a leakdown check on the radiator fill neck. It was dribbling from a few places toward the middle of the head under pressure and one spot with zero pressure.

These are mystery heads. I thought I checked them for squareness, but I may have only done one of the heads, twice by mistake. My machinist will be able to tell me what's going on with them, tomorrow.

This should be a quick fix, though. All of the other fitting and fabrication work is done. It should just go back together how it came apart.
 
Don had a look at the gaskets. Said they could be reused. I'm reluctant. The heads had a bit of a rough spot near one of the water jacket ports on the head that was leaking. He's convinced that the surface was inadequate for a good seal with the Mr. Gasket .028's.

He's gonna shave .005" from them and see if that takes it all out.

These gaskets have been compressed and marked per side. They aren't damaged, as far as I can tell. I can mic them to see crush, but I'm wondering if I should buy new ones or just put these back on... Decisions...
 
Don't second guess yourself, buy new ones.
I always spray mine with copper gasket sealant. Something to think about.
 
The gaskets had some kind of an elastomeric coating on them, from the get go. The sheet that came with them suggested three tightening sequences, rather than two and to install them without any coating, so that's what I did.

Got the heads back. They look sharp. Don did go .010" on them. He said that the one that I saw leaking had some nonsense by one of the water passages that required a little more than.007 to trim out, but that it was flat and the other had a slight twist in it that required a touch more than .008" so he rounded up.

He said that between the two heads, if the conditions of both at their best were combined, I'd have one good cylinder head. One had a good surface, but was tweaked and the other was straight, but had a crummy seal surface.

I think I'm going to order a new set. The old ones look like they are ok, with a few small specks here and there that were lost in the process, nowhere important, but after having such a hard time with these sealing, I'm with you on this one, Shawn. I'm not going to risk it and have to pull the deal apart again.

The .010" cut makes me wonder if I should blend the flat side to the chamber, a bit. I'm going to cc one of the chambers again and see what these are at, now. Hopefully it didn't lose too much. If it drops a full 1cc, it will bump the static from 9.75:1 up to 9.89:1.

Dynamic is still way lower at this altitude with this cam, so I think I can run mid-grade without any trouble on about 32 total advance WOT as a starting point. I'm going to recurve the dist. after it's broken in to get total timing in at around 3k and watch how it progresses up to that point.

I think I'll pressure check the engine again, before I fire it to be sure everything is sound.

I think I should also straightedge the block again.
 
Dave,
The fel-pro gaskets, just spray the new ones.

I was taught this trick by my buddy 20 years ago, he still is a mechainic for chrysler.
2.2 dodge motors with heads leaking coolent, he would lift the head, not tacking them all the way off, slide out the old gasket, slide a new gasket coated with permatex copper in.
He worked flat rate and he said only 1 out of 10 would come back that actually had a crack.
 
I think if it doesn't seal this go round, I may give the copper spray a whirl.

I think I'll go 85#, no dice/ leaking, copper spray and use the same gasket w/ 95# so I will still have crush.

I want to keep using these Mr.Gasket 1121G gaskets, because with the piston combo, it puts quench right at .039" They have a very different surface texture than the typical Fel-Pro blue sets. They feel like silicone and have a waffle texture that I'm guessing has something to do with how they bite, under temp and tension.

The only down side to cutting .010 is overall volume loss for a street motor, but I don't think it will be that big of a difference. I still haven't measured CC yet. I will tonight.

I know that it's on a really random curve, but a CC comparison from a stock 302, to something trimmed .010" might be useful for someone else, so I'll post the results.

If I do decide to blend the chamber, I'll cc before, given the number, if I don't like it, I'll go ahead and check cc again after and post results.

Looking at the gasket on the leaking side, there is some kind of damage on the gasket, where the coating was torn off, near one of the water ports in the center on the outside, which is where it was weeping. I may have had some kind of problem, there, that I didn't catch. The side with the warped head sealed, surprisingly.

I doubt it will leak this time, but I'm going to pressure check to be sure.

Time to dump the oil and check for coolant. I haven't run the pump yet, so if there is any water, it should come out separated. I may be able to filter it out, if there is any.
 
Sorry to hear,Dave.The copper works,have used it. Curious,to see this run.
 
Dont forget to check the deck for straightness......
What a nightmare... Keep Chip-in away at it...you will win...
 
The reason I don't think the block is screwed up is because I was running the 170K+ metal shim gaskets with the original heads, up until it was parked where it's being worked on. It never lost a drop of coolant, with the new radiator, never overheated, even with the old one.

In fact, I had a hard time getting this thing up to a reasonable running temp. Dropped the 180° thermostat and ended up going 195°.

When I looked at the head that was leaking, Don caught something that I didn't, near one of the center, outer water passages, which is where it was leaking, so I think it was a surface thing, rather than straightness, since the tweaked one actually sealed, but didn't have any odd areas on it's surface.

I still haven't touched it. I've been busy, working on an album cover that needs done by the end of the month. I think I will be in luck, this weekend, though. The nice thing about this fix is that I have a spare intake gasket set and it's a no-brainer put back together deal with no re-engineering/ moving parts around. It's all done, down to the air cleaner wingnut and nylon washer that sits under it.

I just hope the 7 1/4" holds up long enough for me to get the 833 trans and 8 3/4" built by the end of the summer. I think it's time to buy a Jeep for the winter, or something.
 
Lost .5cc in the decking. Gained it back after chamfering the edges of the chamber. It's right back to where it was after I checked them all after the work.

I think I'm just going to bolt this thing together, now. The edges, especially by the valve opennings are a lot smoother, now with the modification I made. Should help with flame and a little with everything else.

I finally found a better dynamic calculator that allows me to put altitude numbers in. It's right at 8.9 or so, static. Dynamic comes in right at 8.4, static at sea level is somewhere at 9.7:1, so I don't think I need any more volume from these ports to get it into mid-grade. The chamfering was more to get rid of the nasty edges by the valves cleaned up.

Got the oil prime shaft ready for tomorrow. Stoked.
 
Dave,
Good luck
Post the dynamic caculator link with altitude.
I but the motor fires up with no issues.
 
Got it fired.

Total timing coming in at around 2800-3000 @ 36° total.

Broke in the cam between 1500-3000 bursts, ran smooth.

Shut it off, cranked back, so I trimmed it back 2°, tried the starter again, no problem, initial set, but I think vacuum needs work. It's a replacement distributor on warranty. I think it could due to have a little more vacuum advance. I'll work on that later.

Got idle adjusted at 800 RPM, throttle response from primary to secondary needs adjusting.

Took it around the block, carb hit some dead spots in throttle position. I pulled up into the driveway and right before I pulled into the garage, heard a distinct rod knock.

I'm not sure what let go downstairs, but it could have been a rod bolt or spun bearing. It was not pinging when I drove it around the block. I think coming up my steep driveway did something in that was a loose end.

I shut it off right away. Oil looks good. I don't think I hurt anything else, so hopefully I can just get this apart, get it corrected and get it back together.

I'm gonna buy stock in gasket company shares so this **** starts paying for itself.

I'll be fine once I get it.
I'll be good.
[ame="http://www.youtube.com/watch?v=3Z_Ys3BO_4M"]Pursuit Of Happiness[/ame]
 
Check the converter bolts, I have had them come loose before.
 
Good idea. Converter bolts do sound ugly when they get loose.

It just happened all of a sudden. It wasn't like a quiet noise that progressively got worse. The car was idling and it just started making it.

Another thing that occurred to me is that I tac welded a splash shield into the oil pan. I suppose if something changed shape in the heat, it could be hitting a balancer.

Before I tear the engine down, if I end up going as far as pulling it, I'm going to take the pan off, if I can't see anything in the valvetrain.

It's a little too low pitched to sound like a valvetrain issue, but I did catch it at the right time to keep it from getting any worse than whatever is hitting, be it a crank journal or whatever it is.

The thing that spooks me about it, though, and one reason why I don't have high hopes for this crank, is that I had no temp on the gauge. The sending unit that was on my 2bbl never made it's way on to the 4bbl intake. there was one that I had, but I got no reading off of it at the gauge. I need to check the connector again and if I get signal on full ground, I'm going to replace the sending unit.

If the connecting rod took a shot, it's probably from heat.
 
Popped the inspection window on the dust shield and checked all four. Nothing loose. The frequency, pitch and volume against the idle sound like a rod knock. It's consecutive to the RPM of the engine and I'm sure if I didn't care about parts and started pulling plug wires, I'd find it, but I don't want to risk hurting anything else.

I think I'm just going to gear up a forged crank that I have access to and it's matching rods to do a swap with new bearings and a fresh turn and polish.

I think that will be the least expensive and quickest way for me to get this back up and going.

If I don't run the engine anymore, I think I can keep track of the lifters, piston assemblies and get it all stuffed back under the hood as soon as I have another crank and rod set ready.
 
Dude that suuucks I just got the 383 back together and running in the Polara and thankfully it runs better than it did when I pulled it which was already pretty good. I can give you back your engine hoist and stand btw and let me know if you want a hand getting that pesky 318 sorted out.
 
Been there, caught it. At least all 8 bores/rings/pistons,are intact.
 
Is it a deep thump thump thump?
What is the oil pressure?
I know you used a micrometer on the crank and plastigauge, and had the rods reconditoned, but did you check the conecintricity (sp?) on the big end of the rods with the caps torqued on the bench?
Did you use the factory rod bolts?
 
Reused the factory rod bolts on the rods they came off of.

I'm starting to debate a rod bolt issue and I think I may have had a heat vs bearing issue.

It broke in just fine. No issues at all. Minimal smoke on start up, burning all of the assembly oil in the chambers. Timing was fine. It ran really smooth. No vibrations or misfiring, even after I broke in the cam for 20 min and set idle. I was able to trim 30rpm on the idle speed. It is a very responsive engine.

The one thing that surprised me, though was that I didn't get any reading on the temp gauge.

I checked the lead and it works when grounded out, so the temp sending unit that was on the intake was locked open.

I didn't think anything of it, but the engine did get hot as I suspected it would, during break in, but I have no idea how hot. I'm thinking now that was the culprit, coupled with the bearings I chose.

I used a set of King Si Aluminum bi-metal, because the elasticity is supposed to be more forgiving on the shape of the rod/ cap, like you are talking about, Mr. Ireland.

What I didn't know, until now, after some further research, is that the embedding tolerances of bi-meta constructionl bearings are far less than the tri-metal ones that Clevite, Federal Mogul and other companies use with copper/tin/lead construction.

Newer cars all use bi-metal bearings, because they are supposed to have better reactionary properties, but they are less forgiving. I suppose with the newer iron and CNC RMS inspection surfaces, they can get away with it, but I don't think I'm going back that route.

I think that another crank and maybe even just one replacement rod could do the job with fresh rod bearings. I have access to two cast cranks that haven't been cut, one set of cast connecting rods and one forged crank, balancer and it's matching rods that haven't been cut.

I'm going to pop the caps on the mains anyway, at which point, I'll inspect those bearings and mic those journals against the new crank and see if they need replacing, too, although I doubt it, as long as the new crank is the same, according to the mic.

It was running for less than 10 seconds before I shut it off.

I'll be sure to check the new rods or replacement single (if I go that route) and use a tri-metal bearing, this round.

The good news is that the cam doesn't need broken in.
 
A redundant question. Did you use,new C.R nuts? Often,budget rebuilders,flip the older nuts. This wears the thread's cut,to a dull edge on both sides of the thread. Just a long shot.See it happen,more than once.
 
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