ftransam1

Started the car yesterday and the oil guage went down to 0 and the car starting ticking really loudly. Opened up the valve covers and saw all the rockers were loose and the lifters were all collapsed. Do you think I broke the oil pump drive shaft. I have the 306 cam in there and the motor is new and has 10,000 miles on it. Or do you think the lifters were crappy to begin with (they were cheapo), could they collapse on their own? anyways, thanks

Ryan

shoebox

All collapsed lifters? Doesn't sound plausible. However, it does sound like you are going to have to open up the engine to see what happened.

ftransam1

yeah I broke the oil pump drive shaft (gear). Is there a company that makes a stronger one that doesn't knife edge and break?

Lonnie Pavtis

An aftermarket shaft is generally under $20, so there is no reason to not have one.

But, unless you have a very high pressure or high volume pump, the shaft usually fails due to a foreign object stuck in the pump causing it to lock-up.... then the shaft breaks. A piece of dirt, casting flash or a small metal shaving will lock it right up. Cleanliness is very important for this reason. When you pull it apart, disassemble the pump to verify it is clean & undamaged.

EviLZ28

Not to Hi-jack the thread but My oil drive also Knife edged and broke as well. The motor has 9000 miles on it and has the Hotcam installed.The drive was installed new when the motor was rebuilt. The Oil pump still turns fine. I am also running a high volume. Could this be the problem. I dont want to install another new oil pump drive and have it wear out the same way as I am driving. Any suggestions???? I am sitting hear with my Intake off waiting for any suggestions.

ftransam1

supposedly gm makes a new drive gear that is made of a slightly different material that is supposed to hold up to the hv oil pump and billet cams. GM part # 10456413. However the gear is the right size but the hole in the middle of the shaft is a little larger. I put it on there anyways with a new roll pin and centered it so it spins true. Haven't had a problem yet.

EviLZ28

I found a part number for a Hardened gear from Gm for use with a .425 diameter shaft drive. #19052845 It says it is for Roller cams and is Hardened. I found it on this web sight:
http://www.sallee-chevrolet.com/Distributors_And_Parts/
I might order this one.

tireburnin

Crower also makes a brass version if those don't work. Double check the inside diameter, as there are a couple of different sizes. I had the same problem and went the brass gear route. I got the hardened GM part that I found from seaching the forums, but it was the wrong internal diameter. Double check before you order.

EviLZ28

I just got the engine back together after installing the new gear # 19052845
The gear was an exact size as the original LT1 gear but it is alot harder. I tested it against the old gear and the old gear was super soft compared to the new gear. I started it up today and the motor has great oil pressure and is extremely quiet. I am glad as I was scared I might have hurt the bearings in the motor. I would recommend anyone who is running a high volume oil pump to put this gear in. The gear costed me 38.00 bucks

MaxLean

How did the cam gear look? If you munched the oil pump drive gear, the cam gear probably suffered damage as well and likely wont last long. BTW, I had the same thing happen to me. In my case, the cam gear appeared ok, so I installed a new oil pump drive assy. Inspected it at 500 miles by pulling the intake, and it seemed ok. That was 1500 miles ago. I'm still very leary...

EviLZ28

The cam gear was great. I ran a camera down into the block to check it. It was fine. The Cam must be made of a harder metal then the oil pump drive gear. I was talking to a engine shop and he told me that GM has switched vendors who produce their camshafts and he thought he read somewhere that they changed the camshaft materials. Anyone know what metal they are using? He told me what he thought it was but I dont remember. I want to say 8640, does this sound right?

ftransam1

Just broke that hardened gm gear today after 1000 miles. Don't know what's going on but I'm really tired of this problem. If I take out the high volume pump and put a stocker back in will it fix the problem? Or where can I find a gear that will hold up!!! Help

tireburnin

You can try brass (which doesn't last as long as a comparable steel one = 20-30k miles) like I am using, or swaping the pump will likely solve the problem by releaving the stress on the gear.

MaxLean

Your cam gear is probably now damaged and is excessivly wearing the new oil pump gear. Unfortunately you'll probably need to replace the cam.