Topic: Worn Cam... replace or too late
in Forum: C3 Engines
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I had replaced the heads late last year and the car was running great. Lately it has been making a lot of valve train noise. I pulled the valve covers and found a rocker that I can no longer adjust, nut is tightened all the way. Pulled the intake and that lifter is sunk into the lifter bore a good 1/16 inch, So I need Cam and lifters. I have two choices, replace the Cam with the motor in the car. Or pull the motor and open the can of worms.
|UPDATED|3/22/2016 3:31:35 PM (AZT)|/UPDATED|
My preference is to replace the cam. My concern is that all the metal that is ground off the cam lobe and lifter has contaminated the oil. I know I can swap the cam with the engine in the car by removing the radiator and hood, just wondering what others might have done. Can't really afford to deal with a rebuild right now.
Its had a lot of recent oil changes and I have always used zinc additive. Just drained the oil and it is pretty clean, thinking of dropping the pan to see whats inside.
tia,
Pat
|UPDATED|3/22/2016 3:31:35 PM (AZT)|/UPDATED|
Daytona Yellow '75 350 Muncie 4 spd
'73 454 on the engine stand.
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if it were me I would drop the pan, pull the oil pump cover and inspect for wear. The oil filter will trap a lot of your metal from the worn cam lobes but the pumpvis up steam of the filter. If the pump looks to be ok then I would drop #1 rod and main cap to inspect tge bearings for signs of wear.
I pulled the lifter out and it is a full 1/16th inch shorter than the others and it has a concave bottom from the cam lobe wearing it out. So there is some metal inside. Today I am going to get the front of the motor apart, pull the hood off and get the cam out and drop the pan.
Found an Edelbrock cam and lifter package for $180.00 and I could easily replace the oil pump since I am down to a short block w/o a pan. Not sure I want to disturb the rod bearings at this point. If the rod/main bearings are shot the motor is coming out.
This short block is stock and I want to rebuild it, but I can't really do it correctly until the summer when I have more time and money. I really just want to get it back on the road. Hopefully the bottom end is in decent shape.
Thanks for the replies.
Pat
Daytona Yellow '75 350 Muncie 4 spd
'73 454 on the engine stand.
Lifetime MemberModerator
Duncanville, TX - USA
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Back in the late '70s/early '80s, Chevy had a HUGE problem with the cams on small blocks. In the end, it was determines the cam lobes were never hardened properly from the supplier. I can't even begin to remember how many cams I swapped on '78-'79 cars back then, some with as few as 20,000 miles.
Going from memory, GM's recommendation(for the dealers) was to change the cam/lifters, flush the oil, change oil & filter. Run engine to break in cam, then change oil/filter again. Run engine another 30 minutes or so, then another oil/filter change. I doubt you have any other related damage to the engine, but you can make a decision on if you want to go any deeper once you get the oil pan off.
Be SURE when you do change the cam that it comes with a bottle of break-in lube. It should, but if it does not, GET SOME! Follow the manufacturer's break-in procedure to the letter. If the engine doesn't start right up after the cam change, don't keep cranking it...find out WHY it won't start.
Going from memory, GM's recommendation(for the dealers) was to change the cam/lifters, flush the oil, change oil & filter. Run engine to break in cam, then change oil/filter again. Run engine another 30 minutes or so, then another oil/filter change. I doubt you have any other related damage to the engine, but you can make a decision on if you want to go any deeper once you get the oil pan off.
Be SURE when you do change the cam that it comes with a bottle of break-in lube. It should, but if it does not, GET SOME! Follow the manufacturer's break-in procedure to the letter. If the engine doesn't start right up after the cam change, don't keep cranking it...find out WHY it won't start.
Joel Adams
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I just ordered a cam from Edelbrock that matches the performer intake I have, Cam number 2117. It'll be here in 5 days or so. Meanwhile I just moved the car outside and degreased the underside of the engine, tranny and the front. Its much cleaner now and will be easier to work with. I am getting a new pan since the old one is beat up and I am going to go with a new oil pump.
|UPDATED|3/24/2016 7:06:31 AM (AZT)|/UPDATED|
I thought about dropping and cleaning the pan, remounting it w/o a gasket. draining new oil into the galley and down into the pan and then use the oil pump/distributor drive to run oil through the engine and through a new filter. Maybe do that twice to make sure most of the debris is out before installing the cam and buttoning it up.
Right now Its back in the heated garage drying off, I am going to get into the front of the motor and pan tomorrow after it is dried. We'll see what the pan looks like, I am going to look at the inside of the filter that just came off too. That oil was fairly new and I am hoping to see the filter holding most of the gunk..
@F4Gary, I considered a roller cam, but for this application a roller cam would be similar to putting lip stick on a pig and it would be another $200 that goes into this engine on top of what i already have in it. BTW, the F4 Phantom has and always will be my favorite military aircraft.
Thanks,
Pat
|UPDATED|3/24/2016 7:06:31 AM (AZT)|/UPDATED|
Daytona Yellow '75 350 Muncie 4 spd
'73 454 on the engine stand.
apesa63 said:
I just ordered a cam from Edelbrock that matches the performer intake I have, Cam number 2117. It'll be here in 5 days or so. Meanwhile I just moved the car outside and degreased the underside of the engine, tranny and the front. Its much cleaner now and will be easier to work with. I am getting a new pan since the old one is beat up and I am going to go with a new oil pump.
I thought about dropping and cleaning the pan, remounting it w/o a gasket. draining new oil into the galley and down into the pan and then use the oil pump/distributor drive to run oil through the engine and through a new filter. Maybe do that twice to make sure most of the debris is out before installing the cam and buttoning it up.
Right now Its back in the heated garage drying off, I am going to get into the front of the motor and pan tomorrow after it is dried. We'll see what the pan looks like, I am going to look at the inside of the filter that just came off too. That oil was fairly new and I am hoping to see the filter holding most of the gunk..
@F4Gary, I considered a roller cam, but for this application a roller cam would be similar to putting lip stick on a pig and it would be another $200 that goes into this engine on top of what i already have in it. BTW, the F4 Phantom has and always will be my favorite military aircraft.
Thanks,
Pat
Mine too!
apesa63 said:
I just ordered a cam from Edelbrock that matches the performer intake I have, Cam number 2117. It'll be here in 5 days or so. Meanwhile I just moved the car outside and degreased the underside of the engine, tranny and the front. Its much cleaner now and will be easier to work with. I am getting a new pan since the old one is beat up and I am going to go with a new oil pump.
I thought about dropping and cleaning the pan, remounting it w/o a gasket. draining new oil into the galley and down into the pan and then use the oil pump/distributor drive to run oil through the engine and through a new filter. Maybe do that twice to make sure most of the debris is out before installing the cam and buttoning it up.
Right now Its back in the heated garage drying off, I am going to get into the front of the motor and pan tomorrow after it is dried. We'll see what the pan looks like, I am going to look at the inside of the filter that just came off too. That oil was fairly new and I am hoping to see the filter holding most of the gunk..
@F4Gary, I considered a roller cam, but for this application a roller cam would be similar to putting lip stick on a pig and it would be another $200 that goes into this engine on top of what i already have in it. BTW, the F4 Phantom has and always will be my favorite military aircraft.
Thanks,
Pat
+ on the F4 Phantom
So I finally got the cam, took a couple days. This is a stock type hydraulic with more lift and duration than factory. I am going to replace the timing chain and was considering whether to go with a timing chain setup or a gear drive setup. I'm fine with the gear noise and I know they're noisier.. in a good way than a timing chain.
Was wondering if anyone had replaced the stock chain with a gear drive and if they liked it..
tia,
pat
Daytona Yellow '75 350 Muncie 4 spd
'73 454 on the engine stand.
in Forum: C3 Engines
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