Re: High Idle knock

Sat Aug 10, 2013 11:07 pm

I would go ahead and pull the pan and check all journals and bearings. If a bearing is bad you may ruin the crank trying to figure it out.

Re: High Idle knock

Sun Aug 11, 2013 8:01 am

My '55 Cub developed a knock a couple years ago just before the Cub Tug. We dropped the oil pan, and several experienced folks took a look and wiggle and confirmed what they had suspected...#1 rod bearing was loose. I did not run it again until I had it worked on, which was fortunate, because it turned out I was able to avoid a total engine rebuild. I was able to polish the crank and only replace the bearing on #1.

I suggest you follow the above recommendations of dropping the pan, look for metal in the bottom and closely check for any play in the rods. Right now you may still be lucky.

Good luck.

Re: High Idle knock

Sun Aug 11, 2013 9:39 am

Youre getting some great advice....I love to see this forum work to solve a members problem.... :{_}:

Re: High Idle knock

Sun Aug 11, 2013 9:43 am

pickerandsinger wrote:Youre getting some great advice....I love to see this forum work to solve a members problem.... :{_}:


Agreed! thanks again guys. It's a beautiful morning, so i'm going to pull the pan and have a "look and a wiggle" :wink:

Hopefully I'll be the only one wiggling (with delight at not finding anything loose!) 8)

Re: High Idle knock

Sun Aug 11, 2013 12:04 pm

Ok, pulled the pan, I found one big hunk of metal.. doesn't look like a bearing to me, and none of the rods seem to have much play. what does it look like to you guys? No, there wasn't a dime in my engine, that's just for size comparison. :wink:
Image
All of the rod bearings wiggle just a little side to side. Does that mean they all need to be replaced? or is that normal?
Last edited by Eoghan on Sun Aug 11, 2013 12:15 pm, edited 2 times in total.

Re: High Idle knock

Sun Aug 11, 2013 12:10 pm

Looks like a washer of some type, maybe..Must have come from somewhere.....Did you check the mains by any chance...

Re: High Idle knock

Sun Aug 11, 2013 12:12 pm

Lock washer from hydraulic pump.

Re: High Idle knock

Sun Aug 11, 2013 12:14 pm

Should be a nut in there too :D pull the hydraulic pump and see if the nut and washer is missing, it may have been lost and repaired before. And this may be your knock.
Boss

Re: High Idle knock

Sun Aug 11, 2013 12:22 pm

There is a slight side to side movement on connecting rods at the crankshaft.

While you have the pan off, suggest purchasing plastigage from auto parts store and gauging the rod and main bearings. Guessing plastiqage will cost about $7- for two sticks, one stick measuring .001" - .003" and the 2nd stick measuring .003" - .006".

Re: High Idle knock

Sun Aug 11, 2013 12:24 pm

Nice catch guys
Eugene wrote:Lock washer from hydraulic pump.
Boss Hog wrote:Should be a nut in there too :D pull the hydraulic pump and see if the nut and washer is missing, it may have been lost and repaired before. And this may be your knock.
Boss

Re: High Idle knock

Sun Aug 11, 2013 12:40 pm

Boss Hog wrote:Should be a nut in there too :D pull the hydraulic pump and see if the nut and washer is missing, it may have been lost and repaired before. And this may be your knock.
Boss


:shock: where would this nut have ended up??

How should I go about pulling the hydraulic pump? do I need to drain fluid in the system? the manual isn't too clear.
Last edited by Eoghan on Sun Aug 11, 2013 12:51 pm, edited 1 time in total.

Re: High Idle knock

Sun Aug 11, 2013 12:50 pm

Now that I look at it, I think it's been replaced recently. No paint on it!

Image

Re: High Idle knock

Sun Aug 11, 2013 1:22 pm

As a side note, I noticed some metal shavings in the bell housing... throwout bearing? I bet that's what all the noise is when it's in neutral.. do you need to split the tractor to get to that one?

Re: High Idle knock

Sun Aug 11, 2013 2:59 pm

Eoghan wrote:How should I go about pulling the hydraulic pump? do I need to drain fluid in the system? the manual isn't too clear.
Unbolt the hydraulic lines at the touch control block and hydraulic pump. Bucket on floor under each connection works well. You should replace the fluid any way.

Unbolt hydraulic pump. Check inside the front engine cover for a missing nut.

Eoghan wrote:I noticed some metal shavings in the bell housing... throwout bearing? I bet that's what all the noise is when it's in neutral.. do you need to split the tractor to get to that one?
The metal shavings are probably off the pressure plate fingers or throwout bearing bracket. Noise would show up when clutch depressed, not in neutral

To repair you will need to split the tractor.

Re: High Idle knock

Sun Aug 11, 2013 3:17 pm

Soooo... Guess what I found when I cleaned out the sludge in the oil pan? This little guy was hiding under a lot of gunk:

Image

Turns out you guys are pretty good at identifying random torn up pieces of steel!

I didn't pull off the pump yet, and I don't have a torque wrench handy, so I didn't check the bearing clearances. hopefully i'll get to both those things soon.

I couldn't help myself, so i fired her up and the knock is still there. I can only hear it at full throttle, and only with the clutch engaged (When i let up the clutch there's some nasty noise coming from somewhere). that means I can't get off the seat and track down where it's coming from...

Tell me if i'm wrong, but i'm guessing I should probably replace the rod bearings in any case since the knock is still there and they do have some play.

I'm learning so much today, this forum and more importantly YOU GUYS rock!