timing chain cover saga, revisited...

Rosco

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Well, I'm in the process of replacing my timing chain and after removing the cover I realized I had a little hole in the surface behind where the water pump lives. I had that hole repaired but the Hack welder who did the repair for me took it upon himself to grind the excess weld off the mating surface with a hand grinder!!
Phase two. I had the water pump surfaced at a legitimate machine shop and am very happy with the work. However, looking at the back side of the cover (the face that mounts onto the engine block) I notice the surface is not true/flat. It seems significantly not-flat to me- I am no machinist but I do believe those guys work in the realm of .0001 of an inch and what I'm seeing is like a sixteenth gap on both ends- if you were to rock a straight-edge from end to end there is what looks like an eighth of a gap!
One of the guys at the shop thought that being aluminum I shouldn't worry about it and he thought the bolts would pull it flat. Again, not an engine rebuilder-that advice sounds pretty hokie to me. '
The crazy thing is the one surface that hasn't been messed with is the one that is looking warped.
Has anybody noticed this before with their timing chain cover? And, any thoughts about going for it and hoping the gasket and RTV will take care of the gaps?
I am aware that I can obtain a new cover but my situation is that I need to throw this thing on now. My car lives in a remote place from me (Mexico) and I'm running out of time. I don't have time to order one (which I should have done in the first place- who would've thought the whole world was going to shut down after I started messing with my motor??) and have it shipped down here. I'm trying to close down shop for the season and right now I'd like to remount all the parts that came off with the timing chain cover.
 
There is a shop which resurfaces cylinder heads that I've been told could flatten my cover with some sort of giant sanding machine. But, this just adds one more trip to town and one more potential problem. I think I'm becoming paranoid.
I should've ordered a new one after the first [bad]repair. It's like two steps forward three steps back. I feel like I'm chasing my tail...I could've been driving it by now. funny how slow a restoration can take when travel is shut down and you're in Mexico and your spanish is equal to a Mexican two year old.
 
Well, I'm in the process of replacing my timing chain and after removing the cover I realized I had a little hole in the surface behind where the water pump lives. I had that hole repaired but the Hack welder who did the repair for me took it upon himself to grind the excess weld off the mating surface with a hand grinder!!
Phase two. I had the water pump surfaced at a legitimate machine shop and am very happy with the work. However, looking at the back side of the cover (the face that mounts onto the engine block) I notice the surface is not true/flat. It seems significantly not-flat to me- I am no machinist but I do believe those guys work in the realm of .0001 of an inch and what I'm seeing is like a sixteenth gap on both ends- if you were to rock a straight-edge from end to end there is what looks like an eighth of a gap!
One of the guys at the shop thought that being aluminum I shouldn't worry about it and he thought the bolts would pull it flat. Again, not an engine rebuilder-that advice sounds pretty hokie to me. '
The crazy thing is the one surface that hasn't been messed with is the one that is looking warped.
Has anybody noticed this before with their timing chain cover? And, any thoughts about going for it and hoping the gasket and RTV will take care of the gaps?
I am aware that I can obtain a new cover but my situation is that I need to throw this thing on now. My car lives in a remote place from me (Mexico) and I'm running out of time. I don't have time to order one (which I should have done in the first place- who would've thought the whole world was going to shut down after I started messing with my motor??) and have it shipped down here. I'm trying to close down shop for the season and right now I'd like to remount all the parts that came off with the timing chain cover.
just to clarify:
I had the water pump mating surface of the timing chain cover resurfaced.
 
Set it down on a known flat surface and look at the cover. That will tell you if it's warped or not. A decent machine shop should have a surface plate to examine it. If not, a counter top should be relatively close as the timing cover isn't as an "critical" part like say a cylinder head and its mating surface.
 
Set it down on a known flat surface and look at the cover. That will tell you if it's warped or not. A decent machine shop should have a surface plate to examine it. If not, a counter top should be relatively close as the timing cover isn't as an "critical" part like say a cylinder head and its mating surface.
Thanks for your response. I used a straight edge as well as a flat surfacer to see that the face of the timing chain cover is indeed warped.
When you say it "isn't as critical as a cylinder head" do you think there is a chance it would not leak as is? We'd be putting a lot of value/merit in the tightening of the bolts and the gasket/gasket sealer making up the difference.
 
Thanks for your response. I used a straight edge as well as a flat surfacer to see that the face of the timing chain cover is indeed warped.
When you say it "isn't as critical as a cylinder head" do you think there is a chance it would not leak as is? We'd be putting a lot of value/merit in the tightening of the bolts and the gasket/gasket sealer making up the difference.
but you know that's what I want to hear!!ie "it'll work just fine"!! Moving forward!
 
Warping that much eventually show up as leaks. As a retired professional engine builder .030 would be my maximum limit. Leaks can occur at the coolant passages. JMO
 
Timing chain covers are light steel with a flange. A 2x4 , a hammer and a hard flat surface should help true it up.

Find your high spot and work it down from there.

Or are the small block ones cast? I haven’t messed with a 318 since high school.
 
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Timing chain covers are light steel with a flange. A 2x4 , a hammer and a hard flat surface should help true it up.

Find your high spot and work it down from there.

Or are the small block ones cast? I haven’t messed with a 318 since high school.
Cast aluminum
 
Carry on.
A big hammer fixes a lot of things, but cast aluminum is not one of those.
 
Being 1/8" out & trying to torque it down flat will yield bad results. Cast Al does not bend, it will break, either immediately or later. Machine the hell out of it & you'll have pulley alignment issues. Just get a good replacement and wait to do the job properly later.
 
Well, I'm in the process of replacing my timing chain and after removing the cover I realized I had a little hole in the surface behind where the water pump lives. I had that hole repaired but the Hack welder who did the repair for me took it upon himself to grind the excess weld off the mating surface with a hand grinder!!
Phase two. I had the water pump surfaced at a legitimate machine shop and am very happy with the work. However, looking at the back side of the cover (the face that mounts onto the engine block) I notice the surface is not true/flat. It seems significantly not-flat to me- I am no machinist but I do believe those guys work in the realm of .0001 of an inch and what I'm seeing is like a sixteenth gap on both ends- if you were to rock a straight-edge from end to end there is what looks like an eighth of a gap!
One of the guys at the shop thought that being aluminum I shouldn't worry about it and he thought the bolts would pull it flat. Again, not an engine rebuilder-that advice sounds pretty hokie to me. '
The crazy thing is the one surface that hasn't been messed with is the one that is looking warped.
Has anybody noticed this before with their timing chain cover? And, any thoughts about going for it and hoping the gasket and RTV will take care of the gaps?
I am aware that I can obtain a new cover but my situation is that I need to throw this thing on now. My car lives in a remote place from me (Mexico) and I'm running out of time. I don't have time to order one (which I should have done in the first place- who would've thought the whole world was going to shut down after I started messing with my motor??) and have it shipped down here. I'm trying to close down shop for the season and right now I'd like to remount all the parts that came off with the timing chain cover.
Putting my old and dusty Toolmaker hat on.... I'll tell you exactly what those guys did... They bent it when they clamped it down. Classic rookie machinist screw up... and I'll guarantee it was the low man on the totem pole that got the job assigned to him.

I think it's time to put a bullet in this timing cover so it and you are out of misery.

Someone here should have a used one that they can ship you.
 
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I think you’re onto it Big John, here’s a photo of the cover at the shop clamped down. What else would explain the bent face???
That said, wouldn’t it be possible to bend it back? I agree that a new one would be best but I may be out of here before I could get one shipped down
Also, a possibly game changing revelation with the engine stamp. I followed up with Dave Lux’s advice and looked at the stamp on the driver’s side just below the head. There were two groups of numbers. The first one is “1283” with what looks like a colon after that. The next set of numbers is “2536030-G18-2BN”.
Could this mean I have an 1983 engine?? Unbelievable.
 
All 318 and 360 engines from 1970 thru 1989 use the same front cover. You should be able to find a good used one in Mexico.
 
View attachment 373742 I think you’re onto it Big John, here’s a photo of the cover at the shop clamped down. What else would explain the bent face???
That said, wouldn’t it be possible to bend it back? I agree that a new one would be best but I may be out of here before I could get one shipped down
Also, a possibly game changing revelation with the engine stamp. I followed up with Dave Lux’s advice and looked at the stamp on the driver’s side just below the head. There were two groups of numbers. The first one is “1283” with what looks like a colon after that. The next set of numbers is “2536030-G18-2BN”.
Could this mean I have an 1983 engine?? Unbelievable.
If you bend it back, then the face that was machined won't be straight.

If you are coming back state side, then maybe the option of a lot of RTV might work. I shudder to even suggest it though.

I tried to find the differences between the timing covers and it looks like the big difference is the location of the timing marks and the width of the rubber seal to oil pan.

I also found a pic of a newer cover being used on an older engine. Looks like they just bolted the timing tab on and that took care of everything. They also changed the harmonic balancer so they had to do some other heroics, but it still worked.


67 Dodge Coronet 318cui new camshaft

Someone please correct me, but I think that if those are the only two differences, you can use a newer cover.

The blocks aren't any different, so it should work. AGAIN, THAT'S JUST MY OPINION. SOMEONE THAT KNOWS 318 ENGINE BETTER THAN I MIGHT KNOW THIS
 
I can post a photo of my timing cover. There’s a part number cast onto it as well.
It’d be nice to get to the bottom of the engine year which would help identify the cover.
 
All 318 and 360 engines from 1970 thru 1989 use the same front cover. You should be able to find a good used one in Mexico.
You know I am discovering that they are familiar with the 318 after all down here. I may indeed be able to find a used one and can look into it.
Too, I’m trying to pin down exactly which year motor I have which will help me identify the proper cover for my engine.
 
I can post a photo of my timing cover. There’s a part number cast onto it as well.
It’d be nice to get to the bottom of the engine year which would help identify the cover.
There ya go... We can probably work with that.
 
If you bend it back, then the face that was machined won't be straight.

If you are coming back state side, then maybe the option of a lot of RTV might work. I shudder to even suggest it though.

I tried to find the differences between the timing covers and it looks like the big difference is the location of the timing marks and the width of the rubber seal to oil pan.

I also found a pic of a newer cover being used on an older engine. Looks like they just bolted the timing tab on and that took care of everything. They also changed the harmonic balancer so they had to do some other heroics, but it still worked.


67 Dodge Coronet 318cui new camshaft

Someone please correct me, but I think that if those are the only two differences, you can use a newer cover.

The blocks aren't any different, so it should work. AGAIN, THAT'S JUST MY OPINION. SOMEONE THAT KNOWS 318 ENGINE BETTER THAN I MIGHT KNOW THIS
Personally I wouldn't attempt to use RTV. Cast aluminum doesn't take kindly to bending although heat will warp it.
I summarized the different small block timing covers in the other post but I'm pretty sure he has the 68-69 version with the cast-in marks on passenger side. He could use the later version but would have to confirm TDC, re-mark the damper, and fab up some sort of pointing system. Figured that would be more work than he'd want to do.
 
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