OC 46 knock in fresh rebuilt engine?

bvk · January 15, 2012, 09:35:28 PM

I have a oc 46 with a GO130H engine. I have gone through the whole thing,new pistons,reground crank, main and rod bearings, cam bearings, valves,valvesprings, but I have A knock in the front of the engine. I have had this engine apart 3 times and can not figure out whats wrong. Main bearing clearance is .003, rod bearing .0025, crankshaft end play .008, cam end play .002. It sounds like it is up front by the Governor. I have listened to it with a stethoscope. I have asked Landis and his mechanic. I hope there is someone out there with the idea.

Thanks,

Frustrated

hotratz · January 16, 2012, 02:28:19 PM

Wow, pretty tough without being there and hearing it myself but maybe somebody else has run into this.

bluegrallis · January 16, 2012, 05:40:32 PM

Is there a set screw in the front pulley? I have heard of people finding a loose pulley that sounded like a bottom end knock.

Money Pit · January 17, 2012, 12:33:23 AM

If your useing the manual fuel fuel pump ,I have had problems with pecking sound coming from that on other engines Before. The way to check is totake the two bolts out and lay to the side, there should be enough gas in the carb to iddle for a few mi.

bvk · January 17, 2012, 02:49:21 AM

There is not a set screw on the front pulley, it is a tight fit on the crank with a key and a large nut with a lock washer. So I don't think I am getting any knock from it.
Thank for the idea anyways.

bvk · January 17, 2012, 02:53:01 AM

Thanks for the fuel pump idea, I am going out to the shop and try your idea, I will let you know

bvk · January 19, 2012, 12:53:55 AM

No, the fuel pump wasn't the problem. But thanks for the idea.

BVK

bvk · January 19, 2012, 01:20:09 AM

I might have figured out the problem. There were three different crank pulleys for that engine. One for the diesel and two for the gas engine. The one I have has a casting no. of 261293-C. Landis said that one is heavier than the other(for balance). I got a reground crank and bearings from Zimmermans and maybe that pulley doesn't go with the new crank. I have to call Landis back tomorrow with engine serial #. The only problem seems to be is the parts book shows two crank pulley #s 175 499-A and 175 617-A but only one crankshaft #612 962-AS. So I'm not sure why there are two different pulleys. Maybe I will have to get the other pulley and try it. Does anyone knows why there would be two different pulleys for the same crank?

BVK

oliverchris · January 22, 2012, 05:54:11 PM

Loader vs. dozer or agricultural model, perhaps?

bvk · January 24, 2012, 03:45:19 AM

No the different pulley didn't help, now I have a vibration and a knock. I guess I will put the old pulley back on. Still at a loss as what is making the knock. I need some more ideas.
BVK

Blake Malkamaki · January 24, 2012, 03:51:10 AM

Could it be in the coupling to the hydraulic pump?

hotratz · January 24, 2012, 07:19:02 PM

Quote from: Blake Malkamaki on January 24, 2012, 03:51:10 AM
Could it be in the coupling to the hydraulic pump?

Good guess

bvk · January 24, 2012, 11:01:46 PM

No I don't have the pump on yet. I wanted to make sure the engine was all ok ,no oil or coolant leaks etc, before I put the loader on. I have had the pan and front cover off three times now.
Thanks for the idea anyways.

BVK

lettereat · May 06, 2012, 01:31:46 PM

I have the same machine your referring to. The motor was stuck when I got it. As it worked out, I ended up having the motor 100% rebuilt at an engine/farm repair shop. They did the install and noticed the same noise I think your referring to but couldn't find a cause. We run it, pulled the oil pan, all looked good. We decided to use it and see. That was a year ago, the noise hasn't changed. I've probably put 50 or more hours on it with no problems.

bvk · May 13, 2012, 02:11:35 PM

Hey thanks for the news about your OC-46. But there must be a reason for the knock but I am tired of taking it apart. The only other thing I was thinking is I replaced the crank and gear. Maybe the old cam gear and the new crank gear don't quite match. But I did check for clearance between the teeth. IT has been just setting in the back shed since early winter because I had to get on with other projects. Maybe I will get it out and finish it up and just run it.

Thanks again,
BVK