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V1 Replacing high mileage parts

Metal Mech

Well-Known Member
Metal Mech
Ok so in the next few weeks I will be pulling the engine out of the donor. While I don't plan to do a full rebuild at this point in time I do want to replace the parts that tend to wear at with the higher mileage engines. I am going to list my thoughts on parts that I should replace while I have the engine out. If I am missing anything or if I am planning to replace a part that I really don't need to please let me know.

The biggest one I see all the time is the timing chain and guides. I am planning to get a kit that has the timing chain, balance shaft chain, all the guides, and the balance shaft chain tensioner. I also see a lot of cobalt owners recently changing their timing chain tensioner as well. Its not part of the kit, but I am assuming its probably a good idea to replace that as well?
I am also thinking I may as well change out the water pump, the from main seal, rear main seal and cam seals.
Would swapping out the alternator be a good idea even if it test good? Or just wait till that item is a problem?
I am swapping out the exhaust manifold for a header, but would it be a good idea to removed the intake manifold and change gaskets now?
Clutch will be changed while its apart as well are there any other transmission parts I should look at/change?

Just trying to get a list together as I would like to start purchasing these items so I have them when I am ready.
 
jirwin
All sounds good. Check out ZZP's upgraded chain guide if you so desire: https://zzperformance.com/collectio...etrain/products/zzp-ecotec-timing-chain-guide

My $0.02, leave the alternator unless you're buying a new OEM. Most of the crap you buy at autoparts stores is rebuilt/remanufactured for alternators and starters. For the intake I wouldn't bother (because naturally aspirated), but for the exhaust you might need studs. I got a cheap chineseum header from eBay and it didn't really seat properly until I replaced the studs with stainless ones and put a nice fel-pro gasket. I was getting leaks prior to that on startup. My F23's clutch was finally giving up the ghost at 130k on it only after I installed the supercharger. I would say if it ain't broke don't fix it there too. Worry about it later if when you add forced induction.
 
G
How many miles?
It looks like water pump is about $50.00. I would replace at that cost.
Alternator is $150. I didn't replace mine. It's easy to get to later and doesn't risk breaking anything else if it goes. Depends on your tolerance for getting stranded.
I went ahead and replaced the axles. Fairly cheap and one of mine seemed pretty loose.
 
G
I would at least inspect the clutch and replace if any doubt at all. If the donor was much over 100k, I would probably replace anyway unless it showed signs of being replaced already
 
Rauq
Cloyes 94201S and 94202S are everything you need for the timing set including both tensioners (edit: for non-VVT motors). Add in a Dorman 917-954 timing chain guide bolt if yours hasn't already been replaced. Might as well put a new front main in at the same time since the crank pulley bolt is technically non-reusable. Water pump is up to you, I don't know Ecotec water pumps to be particularly unreliable, but in the same vein as the front main seal, you're already 90% of the way there doing the timing set so it'll never be easier. You'll have to pull the valve cover to do the timing set, so if the valve cover gasket is showing any signs of leaking, that's a good time to do it, although you can also do it later super easy.

Clutch is a good idea before you install the powertrain in the frame, it'll never be easier. Go ahead and put in whatever you envision needing in the future. No point in putting in a stocker if you think you're going to up the power down the road. New slave cylinder will include a new input shaft seal. Might as well throw in a rear main seal while you're in there as well.

Nothing else off the top of my head unless you're seeing issues with donor hardware.
 
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Metal Mech
No the only current issues are the cam and crank sensors which I replaced and possibly the vvt sensors. I know the exhaust manifold is shot so header there.
The water pump was pretty much a “while I’m here I might as well” type of part. Hate to do all that work and it go bad
I apologize for not mentioning the mileage but I am just under 160k
 
Metal Mech
How many miles?
It looks like water pump is about $50.00. I would replace at that cost.
Alternator is $150. I didn't replace mine. It's easy to get to later and doesn't risk breaking anything else if it goes. Depends on your tolerance for getting stranded.
I went ahead and replaced the axles. Fairly cheap and one of mine seemed pretty loose.
Yeah the axles are on my short list but I am not worried about those until I get to stage two. Just trying to get a list of parts before the engine and tans go into the frame.
 
Metal Mech
I would at least inspect the clutch and replace if any doubt at all. If the donor was much over 100k, I would probably replace anyway unless it showed signs of being replaced already
I am still in contact with the previous owner of the donor. I may ask him if the clutch was ever replaced.
 
Metal Mech
So after all the replys what bolts need to be replaced when I do the timing? I see the timing guide bolt listed. Do I need to replace the bolts that hold the cam and crank sprockets on? If so best place to get those?
Also I was already planning to take off the valve cover to paint it up a bit, looks like I have to for timing and I always replace the gasket when I remove the cover.
 
S
Replace all torque to yeild bolts. Cam phasers, crank pully, flywheel, head bolts, and I'm probably missing some. Note only need to replace if you remove them. Depending on the bolt zzp, standard parts store, or gm dealer may have a better price.
 
G
How many miles?
It looks like water pump is about $50.00. I would replace at that cost.
Alternator is $150. I didn't replace mine. It's easy to get to later and doesn't risk breaking anything else if it goes. Depends on your tolerance for getting stranded.
I went ahead and replaced the axles. Fairly cheap and one of mine seemed pretty loose.
You might consider dismantling the alternator and checking the condition of the bearings, brushes and commutator. Mine had one bad bearing, one bad brush and the commutator was questionable (122,000 miles on car). Because of the high cost of replacement, I bought a kit off Ebay and rebuilt it myself. The commutator replacement was a tough, but the rest was easy parts replacement.
 
Rauq
So after all the replys what bolts need to be replaced when I do the timing? I see the timing guide bolt listed. Do I need to replace the bolts that hold the cam and crank sprockets on? If so best place to get those?
Also I was already planning to take off the valve cover to paint it up a bit, looks like I have to for timing and I always replace the gasket when I remove the cover.
You will need a new crank pulley bolt (TTY GM p/n 11589123) and the Dorman timing chain guide bolt (improved design over OE). The Cloyes timing chain kit can be ordered with new camshaft sprocket bolts (edit: if ordered with the correct camshaft sprockets).
 
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Metal Mech
You might consider dismantling the alternator and checking the condition of the bearings, brushes and commutator. Mine had one bad bearing, one bad brush and the commutator was questionable (122,000 miles on car). Because of the high cost of replacement, I bought a kit off Ebay and rebuilt it myself. The commutator replacement was a tough, but the rest was easy parts replacement.
It’s been decades since I rebuilt a alternator but might be fun.
 
Metal Mech
All sounds good. Check out ZZP's upgraded chain guide if you so desire: https://zzperformance.com/collectio...etrain/products/zzp-ecotec-timing-chain-guide

My $0.02, leave the alternator unless you're buying a new OEM. Most of the crap you buy at autoparts stores is rebuilt/remanufactured for alternators and starters. For the intake I wouldn't bother (because naturally aspirated), but for the exhaust you might need studs. I got a cheap chineseum header from eBay and it didn't really seat properly until I replaced the studs with stainless ones and put a nice fel-pro gasket. I was getting leaks prior to that on startup. My F23's clutch was finally giving up the ghost at 130k on it only after I installed the supercharger. I would say if it ain't broke don't fix it there too. Worry about it later if when you add forced induction.
I am guessing for the 2.4 a cheap eBay header is good enough. Will grab a FelPro gasket. Is it worth spending the money on the Titanium bolts from ZZP or just sticking stainless?
 
jirwin
Up to you. I just got stainless because I wanted something less rust prone than the stock ones that were already rusty. I was mostly concerned with even torque values. Stainless would be a good upgrade if your stock ones are rusted. Titanium even better, but costs most. Myself I'd probably just go stainless.
 
Metal Mech
So I got my parts in today. The Cloyes timing chain and balance chain kits did not come with the cam bolts.
Anyone know the part number? Thought I found it on Rock Auto but I think those were for the VVT sprockets not the cams.
 
S
So I got my parts in today. The Cloyes timing chain and balance chain kits did not come with the cam bolts.
Anyone know the part number? Thought I found it on Rock Auto but I think those were for the VVT sprockets not the cams.
These are the ones I used from Rock Auto. I couldn't find the GM part number anywhere, but the Rock Auto bolts did the job.
 
Metal Mech
The OEM number is listed on the Rock Auto page.
Yep just came here to say that. When I clicked the link the parts he posted has the OEM number on it. Which was nice as I was able to verify they were correct since the Rock Auto description says head bolt. Its under Engine: Camshaft Bolt but for some reason every time I search for that specifically it would take me to something else.
 
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