318 timing chain.....and why the engine should come out.

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glhx

glhx

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I decided to change my timing chain just for the heck of it. I like the idea of solid timing that has a mark that stays in one place and doesn’t wander up and down on the balancer when I put a timing light in it. Mine was doing that so I just decided to put a double roller on there. Simple job.

When I took out the timing cover, I saw that the front seal, while not leaking, crumbled in my hand. I cleaned that all up and repainted it. Put a new seal in it and called it a day.

Next few days didn’t sit right. I took my time cleaning and painting the parts with Chrysler corporate blue. Painted the harmonic balancer gloss black and put a bright orange timing mark on it. Why black
I couldn’t see the harmonic balancer anyway because I have a 76 block and cover with a 69 water pump. The water pump covers the mark and you have to remove the power steering to even time the car. I was looking for contrast in the color that I wanted before I started all of this......and timing tape should help as well for total timing so I might do that.

Before any of this was done.......I used a piston stop to check the balancer for slippage.

To fix this I’m going to just put a 69 tab on the timing cover and cut a new mark into the balancer. Paint the new mark orange and the other one black. None of that has anything to do with this thread but I put it in anyway so maybe someone will get something out of that.


The reason I posted to take the engine out.
LOOK AT THAT TIMING GEAR.

I didnt take the engine out for that. I took it out because I thought. If the front seal looks like that. What does the back seal look like. Plus.....why not change the torque converter seal.....it’s probably shot as well.

I already have the whole front end of the engine off and these engines are stupid easy to remove.....took me maybe 2 hours if that. Having a mini starter off a Dakota helps.

I took out the rear main and it was hardened as I suspected .......as well as leaking.
I didn’t want to pull the engine...who would?

Now......I will say to get the rear main out.....
There is a metal wire built into the seal and you use a punch......hit it once and it comes right out.

I hope it seals as the new one slid right in with very little pressure

I didn’t know this wire was in there......until I was staring right at it with the engine upside down. I was trying to push it out because I didn’t research the procedure and didn’t see it .....

Just remember.....use a punch to get the rear main out. If it’s not obvious as to why. Look it up and you will see. I’m saying this so you won’t think otherwise and try another way.

So I got the rear seal in and decided to clean up the oil pan and install a high volume pump with a hardened drive gear. I had this pump sitting around for a few years now so why not?

The bearings are trashed........i should have gotten a picture of them. I did not put new bearings in. I will.....but not this time. I’m going to clean the engine and use the old bearings to do so.....then change them. The high volume pump will keep oil pressure with the added clearance of the worn bearings.....it won’t fix the engine. The oil pressure wasn’t bad anyway. It was 20 psi hot.
I was fine with that. There is sludge (not heavy) all over the engine and cleaning it would be difficult another way. ........I got as much out as I could within reason.
I want to rebuild this engine with Keith 167 anyway and have some machine work done , so it will be fine until then. Most of the sludge was in the pan when removed.
......I’m thinking several rounds of sea foam one at idle change the oil and another set @ 50 mile interval.
.

.............

The main reason for this thread. Was because of what I found in the oil pan. The plastic pieces off the timing gear were in the pan. This was expected. How many of them was not.

there was about 50 small pieces of it in the pick up. Not all of them were caught by the pick up and over time they were so oil hardened and brittle that they crumbled and made dust. I don’t even know how it had oil pressure at all but it did. 65 cold and 20 hot. 318 I guess......not a boat anchor.

The pick up and oil was so trashed with timing gear plastic that it ruined the bearings.
Had I known how bad this was I would have pulled it a long time ago. The 318 is known for being bullet proof so I just figured it would be fine.....maybe it would have been but I doubt it. At least not after 43 years old.

THESE TIMING GEARS........WILL TRASH YOUR ENGINE. Not to mention the 2” of play that the chain had and how can you total time a car with that mess.

So......

clean oil pick up
New timing chain
New front and rear seals
Clean oil pan
All new gaskets
Zinc added with new oil
Easy to see timing mark.......maybe I’ll put timing tape on it.

Should make this easier to time accurately and should increase the life of the engine until it gets rebuilt.
 
I bet you have a lot of valve seals in the oil pickup screen. Maybe that is some of the plastic you seen (50 pcs). But yes, the nylon gear is bad news.
  • Oh yeah, removing/replacing rear main seal, here is a short video I made......
 
now you have me convinced to replace the valve seals. I happen to have a set of them on hand.
 
That chain was ready to slip and bend some push rods and possibly a valve or two. Looks like you actually got lucky.
How many miles on it? Most of the nylon gears would go before 100k back in the day.
 
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Yup yup. This right here is why I always recommend pulling any engine when guys want the easy out to remove the oil pan. You never know what you will find.

To the OP, even though you went back with old bearings, you made smart choices "for now". Good job.
 
I had the timing chain slip in the original 318 that came in my '70 Duster. The entire cam sprocket was sheared; it looked like the first pic except the whole thing looked like the left side, not a single tooth on there. I still have that sprocket sitting around as a memento, that caused me to perform my first engine pull ever.
 
It's "good" to not just change the bearings, because the crank journals will most likely be worn and 'contoured' to the old bearings.
Installing new ones would likely cause the new ones to wear double the speed they would normally do.
A highvolume pump on an old worn engine is usually good insurance to get some more years of service out of it.
But the oilpressure-gauge will usually tell the story here.
 
I would tell you about the exhaust stem seals...
Except they aren’t there.

They are all ground up into dust and went into the pan.
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This is what it looks like after hitting it with compressed air.
There is some sludge in there as well.
 
glhx said:
I would tell you about the exhaust stem seals...
Except they aren’t there.

They are all ground up into dust and went into the pan.
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This is what it looks like after hitting it with compressed air.
There is some sludge in there as well.
Click to expand...

Now, you don't know that for sure. Did you see any remains of exhaust valve stem seals? Some engines did not even have them. They really aren't needed. Earlier engines never had them. If you can see no evidence whatsoever, it probably didn't come with them.
 
Back many years ago when all the timing gears were aluminum with plastic coated gears, I use to do many timing gear/chain jobs. 60-80K was about the mileage they called for a change. Supposedly they were made like that for quieter running.
 
RustyRatRod said:
Now, you don't know that for sure. Did you see any remains of exhaust valve stem seals? Some engines did not even have them. They really aren't needed. Earlier engines never had them. If you can see no evidence whatsoever, it probably didn't come with them.
Click to expand...
Glad you brought this up. I put a bunch of valve seals on engines while still in the car and I was taught by my mentor that you only need them on the intake valves. So this is the way I've done them for 48 years! Tho most people doubt me.
 
This engine was sitting at 126....and looked like it wasn’t taken care of....the Gear was original.

I don’t for sure if it had them....s. It doesn’t look like it came with them because they are all gone and show no signs of whatever would be left and no wear pattern.,,,,the intake side is intact.

Maybe it was just the plastic teeth in the oil pick up.
I can tell you this oil was new and might have a couple of hundred miles on it. It’s black and thinned out

But some of that is gas from where it ran rich trying to tune the carburetor and set the timing.

I’m wondering if I should pull the heads and lap the valves just to get them to seat better.
Then throw some cheap bearings in there and clean out all the crap....maybe get another 50-100k out of it...
Which is fine for how much it’s driven and what it’s worth.

The reason I think that it because...while it has compression. I tried to keep the valves up with compressed air....wouldn’t do it. Had to use some rope.

I did one set of valve seals and then questioned if I should just pull the head off and apart and patch it. If it needs it.

I have some felpro head gaskets sitting around.
 
I would. Chances are the exhaust valve seats are not hardened. You will know right off as the ex valves will be sunk in the heads. You tell with the heads on by looking at the valve stems and see if the ex valves are sitting higher than the intake valves.
 
No 76 should have hardened seats. Most engines after 73-74 came with hardened exhaust seats. For unleaded gas.
 
I think you should do as much to it as you can afford. Especially if you want that much more in mileage out of it.
 
How many miles you think I would get out of this at this point?
126k isn’t too bad...

But the fact it was a hard 126k. No telling...
I’m basically just refreshing this until I get the other 318 done.

I’ll post some pictures of the bearings
 
Hard to tell how many miles you will get but, I can tell you that years ago before it was the norm to buy new crate engines or rotating assemblies, back when we didn't have so many options or parts or money available to us. We use to roll new rod and main bearings, maybe clean the pistons and reinstall with a new set of rings and oil pump. Maybe a valve job on the heads,timing chain/gears. They would run just fine for many miles.
 
glhx said:
I can tell you this oil was new and might have a couple of hundred miles on it. It’s black and thinned out

But some of that is gas from where it ran rich trying to tune the carburetor and set the timing.
Click to expand...
I suspect more than just rich from carb tuning..... the deposits you see look to be from a regular diet of gasoline in the oil. Does not look to have been going on too awfully long. But I would be looking at the fuel pump for gas leaks, and the carb for leaks down the throat(s) after it is shut off.

Gas leaking down from the carbs often leads to a rapidly worn cylinder. So pulling the heads and looking at the ridge on the bores and checking the diameter is not a bad idea. If I found a lot of ridge in a bore(s), I would not change bearings or rings without removing that ridge.
 
I guess I’m pulling the heads and doing the valves.

I ream it with a ridge reamer from autozone while I’m in there and see if there are any score marks on the cylinder walls.

It probably did get a healthy diet of gas in that oil.
When I got it....the carb was toast and had no choke set up on it.

I also had to pump it a lot to get the timing set up. I ended up having a bad distributor. I put another new one on it and that was bad. Then the carb ssytem I had on it in that picture ran rich as well.

I had my hand in the gas in the oil for sure. I’ve since learned a lot more about how to tune and prevent that sort of thing.
In the near future I’ll start tuning it by wide band with an adjustable metering block on that 600 Holley.
 
If it were mine, i would just change the timing set, front and rear seals, the oil pump, clean the inside of the engine best i can, and replace the valve seals.
I would also replace the core plugs in the engine while it's out, it's cheap insurance and easy to do with the engine out.
If you go farther than this, it will snowball to a complete engine rebuild faster than you think, and if it isn't in your budget right now to do this, then just do the minimum to get the car back on the road.
You were planning to rebuild another engine, put your major money into that.............
 
glhx said:
I guess I’m pulling the heads and doing the valves.

I ream it with a ridge reamer from autozone while I’m in there and see if there are any score marks on the cylinder walls.

It probably did get a healthy diet of gas in that oil.
When I got it....the carb was toast and had no choke set up on it.

I also had to pump it a lot to get the timing set up. I ended up having a bad distributor. I put another new one on it and that was bad. Then the carb ssytem I had on it in that picture ran rich as well.

I had my hand in the gas in the oil for sure. I’ve since learned a lot more about how to tune and prevent that sort of thing.
In the near future I’ll start tuning it by wide band with an adjustable metering block on that 600 Holley.
Click to expand...
Don't ridge ream it just to do that... only do it if you change rings and/or bearings. If you are not changing them, leave the ridge alone for now. BTW, gas in the cylinders can wear them without leaving any notable score marks. Hence my comment to measure them..... I had a /6 that needed to be bored .040" due to a leaky carb (for years with the PO; he just did not know any better) that did not look all that bad just from the general appearance of the cylinder walls.

I can see what DN says.....sometimes ignorance is bliss! LOL
 
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