Should I tear down engine?(496) [Archive] - Chevelle Tech

: Should I tear down engine?(496)


big454blockchevy
Mar 18th, 07, 6:59 AM
I am wondering after finding the distributor gear worn . Should I tear down the engine and flush everything , add new bearings? My cam which is billet roller did not have the bronze gear . It has it now but don't know if it's to late . My cold oil pressure is at 60 psi with a 1500 idle. This dist. gear wearing had been happening since the engine was first started , so the shaving off it would have been present on my first 2 oil changes , right? I checked my oil filters after changing oil and everything looked fine . Nothing found on my oil filters. Also I would the cam gear be badly worn , I've probably put in less than 800 miles on the engine and about 10 1/4 passes. I will go with what I learn here as far as what steps to take. I tested out my car and went up to 6700 rpms and the car kind of cut out again, It's got the bronze gear in it now, new cap and rotor. I will check them again tomorrow to see if the rotor stayed in place. My starter is starting to not engage the flexplate at times. It will engage it then you can just hear it spinning without grabbing the flexplates teeth. Kind of feel it's related.

GRN69CHV
Mar 18th, 07, 8:04 AM
The GM melonized gear works well with a steel core cam, this is what GM uses for all the ZZ & HO big block motors. Flywheel not engaging has nothing to do with cutting out. I think you have a fuel issue. Your '86 Camaro was fuel injected, right? Even if not, it had a closed loop system, did you make changes to the fuel venting system?

big454blockchevy
Mar 18th, 07, 11:11 AM
My camaro came with a 305 cc qjet . It had a return line which now has been left open. The thing about the flywheel , what I meant was that the timing moving around due to the worn dist. gear might have caused the problem with the flexplate as I was starting the engine . Maybe some broken teeth? I'm no expert but I know the starter should be disengaged when the motor is running. :D :D j/k

69-CHVL
Mar 18th, 07, 11:36 AM
I dont know if you can pull the pan in a Camaro or not, but maybe pull the pan and take off some main and rod caps and see what's going on.

jbird
Mar 18th, 07, 12:27 PM
The GM melonized gear works well with a steel core cam, this is what GM uses for all the ZZ & HO big block motors. Flywheel not engaging has nothing to do with cutting out. I think you have a fuel issue. Your '86 Camaro was fuel injected, right? Even if not, it had a closed loop system, did you make changes to the fuel venting system?


I didn't think you could use the melonized gear with a billet cam?

big454blockchevy
Mar 18th, 07, 12:59 PM
I opened up my oil filter and didn't find any big particles in there. I did find some shavings in the filter though, I wouldn't say alot but the filter element had some glitter looking particles. My oil pressure hasn't changed much from when I first started the engine(don't really know if that helps much). Should I check the wear on the bronze dist. gear and give the cam gear a visual inspection as best as I can from the distributor hole? I should have done that the first time I took off the distributor. Wish I still had my digital cam to show what I am seeing. With the oil coming out of the filter as I was cutting it , I did see some greyish looking oil. The oil in the drain pan doesn't look bad at all.

big454blockchevy
Mar 18th, 07, 1:11 PM
I didn't think you could use the melonized gear with a billet cam?
I almost sure I need a bronze gear for a billet cam. A melonized gear is for factor y roller cams

Wolfplace
Mar 18th, 07, 1:43 PM
The GM melonized gear works well with a steel core cam, this is what GM uses for all the ZZ & HO big block motors. Flywheel not engaging has nothing to do with cutting out. I think you have a fuel issue. Your '86 Camaro was fuel injected, right? Even if not, it had a closed loop system, did you make changes to the fuel venting system?
=
No, No, No,,, :noway:
You absolutely do not want to use the GM Melonized gear with aftermarket billet core cams.
The GM steel core is not a billet.

The GM gear is the one of choice for any cast core cam, billet with the cast gear option but not a full billet.
You need either the bronze or the Comp Polymer which I have had mixed results with.
Crane also claims to have a new steel gear that is compatible but I will leave that to someone else to "test" ;)

Wolfplace
Mar 18th, 07, 1:52 PM
I opened up my oil filter and didn't find any big particles in there. I did find some shavings in the filter though, I wouldn't say alot but the filter element had some glitter looking particles. My oil pressure hasn't changed much from when I first started the engine(don't really know if that helps much). Should I check the wear on the bronze dist. gear and give the cam gear a visual inspection as best as I can from the distributor hole? I should have done that the first time I took off the distributor. Wish I still had my digital cam to show what I am seeing. With the oil coming out of the filter as I was cutting it , I did see some greyish looking oil. The oil in the drain pan doesn't look bad at all.

=
I seriously doubt you did any damage to your engine, most of the crap will end in the filter
As for the cam gear, best you can do is visually inspect & watch the distributor gear wear.
If it tears it up in short order you probably have an issue.
Do not expect the bronze gear to last a zillion miles, inspect it regularly for wear.
It is a "sacrificial" part ;)

I would change the oil a few times after warm up to try & remove any left over crap from the cast gear as it is not real good for piston skirts or walls, anything that is "splash oiled"
The bearings will be protected by the filter especially if you have the bypass blocked.

big454blockchevy
Mar 18th, 07, 2:14 PM
Hmmm, I was lying on top of my engine try to look into dist. hole to do a visual on the cam gear and I can't see it. The bronze gear is still ok, with less than 10 milies on the engine since swapped in but don't like the wear on it. It seems yoiu can really see where the cam gear is making contact with the bronze gear. I dont feel this bronze is gonna last long. I think I just contradicted myself!

big454blockchevy
Mar 18th, 07, 2:26 PM
OK, located the cam gear. :D They(the teeth) look to be fine.

Ray Finkle
Mar 19th, 07, 6:48 AM
I am wondering after finding the distributor gear worn . Should I tear down the engine and flush everything , add new bearings? My cam which is billet roller did not have the bronze gear . It has it now but don't know if it's to late . My cold oil pressure is at 60 psi with a 1500 idle. This dist. gear wearing had been happening since the engine was first started , so the shaving off it would have been present on my first 2 oil changes , right? I checked my oil filters after changing oil and everything looked fine . Nothing found on my oil filters. Also I would the cam gear be badly worn , I've probably put in less than 800 miles on the engine and about 10 1/4 passes. I will go with what I learn here as far as what steps to take. I tested out my car and went up to 6700 rpms and the car kind of cut out again, It's got the bronze gear in it now, new cap and rotor. I will check them again tomorrow to see if the rotor stayed in place. My starter is starting to not engage the flexplate at times. It will engage it then you can just hear it spinning without grabbing the flexplates teeth. Kind of feel it's related.


I hope everything works out well for you, it sounds like your engine will be fine. I do have a question about your max rpms. What rpm are you able to get out of that 496? My 496 is done at 6400-6500 rpm and my thought was it was because the 781s could not flow any more to support the engine. Basicaly maxed out the flow of the heads. Any thoughts?

Pete

kjett
Mar 19th, 07, 8:02 AM
How much end play does the camshaft have? What type of distributor are you using? Make sure the distributor gear and cam gear have some clearance. I've had really good success using the bronze gears (look new after several hundred passes). Even when I used to street drive my car a lot I didn't have trouble with the bronze gears wearing out. One of my friends was having troubles with hise engine eating distributors gears. Turned out the camshaft had zero endplay. Fixed that issue and the distributor wear problems went away.

GRN69CHV
Mar 19th, 07, 8:24 AM
Stand corrected. Thought the melonized gear was good for any steel core cam. Guess not.

Tom Mobley
Mar 19th, 07, 9:24 AM
where is the old gear melonized gear you took out? the wear on it is what tells the story here.

the bronze gears do show a more visible wear pattern when you look at them. do you have an HV/HP oil pump?

big454blockchevy
Mar 19th, 07, 10:40 AM
where is the old gear melonized gear you took out? the wear on it is what tells the story here.

the bronze gears do show a more visible wear pattern when you look at them. do you have an HV/HP oil pump?
I should have a standard oil pump , recall we had a conversation about it and we decided to go with a standard oil pump. My old dist. gear should be a steel gear and I've got it here, only no way to post a pic of it.

big454blockchevy
Mar 19th, 07, 10:47 AM
I hope everything works out well for you, it sounds like your engine will be fine. I do have a question about your max rpms. What rpm are you able to get out of that 496? My 496 is done at 6400-6500 rpm and my thought was it was because the 781s could not flow any more to support the engine. Basicaly maxed out the flow of the heads. Any thoughts?

Pete
That's about where my 496s' power ends to , I just have been having trouble getting my governor weights calibrated to where I want the shift at , which I want at exactly 6500rpms but since 6700 is where it shifted I left it there. I know that when it shifts into second gear after going up to 6700 I hit a real good spot in my power band because my car feels like a small shot of nitrous was just injected. I more than likely am revving out of my power band by letting it go as high as 6700rpms. Tried shifting it manually(700r4) and the shifts will lag and shift at close to 7k rpms!

Schurkey
Mar 19th, 07, 12:44 PM
My starter is starting to not engage the flexplate at times. It will engage it then you can just hear it spinning without grabbing the flexplates teeth. Kind of feel it's related.
Is this a stock-type starter? If so, the motor cannot turn unless the solenoid plunger has been pulled in, therefore the starter drive has been pushed out into the ring gear teeth.

First guess: Defective starter drive. Replace it with one that has 5 rollers in the clutch instead of the usual 4 rollers.

Second guess: Shift fork wiped out in the starter. Still available new, or you can flip it around the other direction so the unused part of the fork is pushing out the drive. You could also repair the flat spots by welding new metal onto them, and then grind down nice 'n' smooth.

big454blockchevy
Mar 19th, 07, 12:49 PM
Schurkey thanks for the help. I will check the starter as soon as I can take it off. A thirdgen with a big block and medusa headers is going to be a pain in the arse to take out the starter. I was pulling a little on the electrical connection (have a remote solenoid) and it turned over and started with alot of noise, it sounded awful .