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Finally getting around to changing the timing chain on my 69 L46 engine. The motor has about 72K miles on it, and this is the first time I have done a timing chain. The car showed the signs:
timing marks jumping around when trying to time it, occasional backfire, shuddering, etc. The chain looks original and has major slack in it so it's a good thing I did this. I do have a few Q's for
some of the more experienced motor heads in here though. I aligned this to TDC firing on #1 plug, but in retrospect maybe I should have done this on #6 so the cam and crank marks were closer.
As it is, I cannot easily move the crank and am afraid to put the bolt back in and try to get them closer as I didn't want to accidently twist off the bolt in the crank.
1. So is there a proven way to turn the crank at this stage (balancer and pulley off)? If not, does this look aligned to you? Does this look as if the crank and cam dots are aligned properly?
2. Should I swap out the oil pump now as I removed the oil pan? Is swapping out the oil pump essentially a bolt on process?
3. I had to unbolt the idler arm to get the oil pan to clear the steering arm (to take the pan off). Is there a better way for future reference?
If swapping the oil pump, I strongly suggest replacing the pump's drive shaft with one that has a metal coupler, rather than the OE plastic coupler. Melling and Moroso both offer that shaft.
So a better pic here. I slid the balancer on but used the bolts to turn it - did the job. The dots seem to match up but didn't know if the teeth on the cam and crank gear had to align as well.
The dots seem to line up, but the cam and crank sprockets are a tad off....
The position looks OK. Others will chime in. Did you soak the chain in oil for a few hours? Changing the oil pump is a bolt on job. Jerry
I take it you are referring to the replacement chain? No, I did not - but I will now - thanks for the info. I am replacing the original with a DR timing chain.
If swapping the oil pump, I strongly suggest replacing the pump's drive shaft with one that has a metal coupler, rather than the OE plastic coupler. Melling and Moroso both offer that shaft.
Thanks for the info - I will inquire for the metal coupler.
I would leave the oil pump alone unless it was giving you a reason to change it. The pickup will need to be installed (pressed in) and the clearance to the bottom of the pan needs to be set. Best practice is to braze the pickup in place once it has been installed but you need to disassemble the pressure regulating valve before you heat it up to protect the spring so..... maybe just leave the pump alone if it still works?
So a better pic here. I slid the balancer on but used the bolts to turn it - did the job. The dots seem to match up but didn't know if the teeth on the cam and crank gear had to align as well. The dots seem to line up, but the cam and crank sprockets are a tad off....
Yes, the dots appear aligned just fine. Don't worry about the teeth being off a small bit – there isn't any other tooth position that the chain can be installed on and still maintain that level of dot alignment.
Originally Posted by jpatrick62
2. Should I swap out the oil pump now as I removed the oil pan? Is swapping out the oil pump essentially a bolt on process?
3. I had to unbolt the idler arm to get the oil pan to clear the steering arm (to take the pan off). Is there a better way for future reference?
I'd not change the oil pump just because it's exposed. There isn't anything that can really go wrong with them unless something pretty catastrophic has occurred elsewhere. You could settle your mind a bit by pulling off the pump's gear cover and inspecting the teeth and rubbing surface on the inside of the cover where the teeth ride. Unless you see severe cover scoring and damaged teeth, it's fine to use what you have.
Removing the 2 bolts for the idler arm to the frame is pretty simple and quick and requires no pickle forks or joint separators.
If you have the time to wait for parts, I recommend a locking plate for those camshaft bolts. It's around $7 at Summit. By bending little tabs on the plate, it secures the bolt heads from ever back out. Sometimes Loctite blue needs a little help.
If you do order the plate, throw some Comp Cams break-in oil on the chain too.
And if you do remove the oil pump for inspection, by all means upgrade the driveshaft also.
Why do you think you need to replace the oil pump?
Because of age and mileage, maybe, as well as "while I've got the pan off"..... Having said that, I'd tend to keep the pump, but at least replace the driveshaft and coupler, because if the pump still has the plastic coupler, it's possibly over 50 years old, and likely to be brittle. Personally, I wouldn't trust it, and a new shaft/coupler is inexpensive
Why do you think you need to replace the oil pump?
No real reason other than I have the oil pan off anyway and have access. However if it's more than a bolt on operation, then I'll probably back down on that. I was assuming I could just order a new pump and use the old pickup, didn't know it was brazen on.
Because of age and mileage, maybe, as well as "while I've got the pan off"..... Having said that, I'd tend to keep the pump, but at least replace the driveshaft and coupler, because if the pump still has the plastic coupler, it's possibly over 50 years old, and likely to be brittle. Personally, I wouldn't trust it, and a new shaft/coupler is inexpensive
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you have to pull the oil pump and again, another unnecessary project....next they will have you putting in a LS. Never heard of one coming apart.
But If you are thinking of it you may as well do it, no better chance than the present. just measure the pickup off the other pump and get it close, bolt it together and then tape a loose ball of aluminum foil on the pickup and push the oil pan into place. Pull it apart and see how much gap you have. Adjust it as necessary and just put 2 tack weld on it, no need to get fancy. When you pull it apart that drive rod will come out. Once you get everything correct swap the new pump drive in. Its not difficult.
Last edited by Rescue Rogers; Jan 2, 2024 at 05:22 PM.
you have to pull the oil pump and again, another unnecessary project....next they will have you putting in a LS
ls is way too much $$ for me. i just want to get a reliable driver that starts and runs well. I will send out the original balancer to DamperDoctor but other than a DR timing chain and new water pump, everything else is stock. Oh, and I will paint all the parts and use a one piece oil pan gasket.
You won't be replacing the plastic / nylon coupler. An upgraded pump shaft will have a steel coupler "built in". The shafts are less than $25.
The oil pump has only one mounting bolt. Once removed, the pump & old shaft will drop down & out.
If you are not into welding a pickup screen on a new pump, Jegs sells a bracket that clamps onto the pickup tube. The bracket bolts onto the pump cover / housing.
Very simple, no welding, super strong and the pickup tube angle is still adjustable should you change your mind later. Once you weld a pickup in place, you are committed to the angle you chose.
Some people would say: "only a fool would not swap the pump & shaft while the pan is off".
Others would add; only a fool would not change the rear main seal while the . . . . . .
So, as you can see, you can go on & on & on with this project.
Only you know the mileage, the history of the car and the condition of the pump, the size of your wallet.
Fortunately, all these parts are fairly cheap.
I would like to add, if funds are available: only a fool would ever reinstall oil pan bolts.
After being introduced to an Oil Pan Stud Kit, it's the only way to go. (especially when laying on your back on concrete with a One-Piece gasket)
Last edited by HeadsU.P.; Jan 2, 2024 at 06:03 PM.
You won't be replacing the plastic / nylon coupler. An upgraded pump shaft will have a steel coupler "built in". The shafts are less than $25.
The oil pump has only one mounting bolt. Once removed, the pump & old shaft will drop down & out.
I would like to add, if funds are available: only a fool would ever reinstall oil pan bolts.
After being introduced to an Oil Pan Stud Kit, it's the only way to go. (especially when laying on your back on concrete with a One-Piece gasket)
I did purchase the Fel-Pro one piece oil pan gasket, and it comes with new (longer) bolts - I assume because of the gasket thickness. The old pan had some RTV sealer in spots and there was evidence
of some oil seepage.
I take it that to replace the oil pump shaft I should remove the distributor first, correct? Not an issue as I've replaced distributors before - I was assuming that getting that shaft key in the exact location (relative to the distro shaft key) it was before hand would be almost impossible. I would just mark the location of the rotor (pointing at #6 now that I moved the cam and crank marks on top of each other) and then replace the distributor to the same location.
Timing Chain Replacement
i just want to get a reliable driver that starts and runs well. I will send out the original balancer to DamperDoctor but other than a DR timing chain and new water pump, everything else is stock. Oh, and I will paint all the parts and use a one piece oil pan gasket.