Author Topic: Engine Trouble, Need Help! (Read 6149 times)

bholzgen · « **on:** September 05, 2013, 12:00:56 AM »

2 Winters ago I rebuilt this motor. Complete top and bottom end. New crank, bearings, seals, and piston. Hotrods longrod crank, Wiseco piston, and all OEM Honda bearings, seals, etc. The motor has roughly 30 hours on it since rebuilt.

While installing a CR ignition, I noticed some play in the crank. Please note, when rebuilding the motor the main bearings were not press fit. I was told to use a strong bearing retainer on the main bearings. Well, it appears that has broke loose and the bearings are moving. There is about a 1/16 of an inch of side to side play. There is absolutely no up and down play.

I really have no idea what to do at this point. I know over time the main bearings begin to spin in the case, causing them to wear slightly.. And with the cases being as old as they are this cannot be that uncommon. Do I split the cases? The bottom end is fresh, and I am thinking about investing in a new top end. Most likely a 310.

Here is a photo of what I am talking about:

Pumashine · « **Reply #1 on:** September 05, 2013, 12:58:27 AM »

Like if you had a 1/32 shim on each side of the crank it would hold it in the middle? I will make you a couple if you want.

Tbone07 · « **Reply #2 on:** September 05, 2013, 08:36:53 AM »

I'd be interested to hear a response from a builder on this. My cases are getting close to doing this. I can see spin marks in them

What about ESR cases? Have they been proven to be good, working units yet?

Pumashine · « **Reply #3 on:** September 05, 2013, 08:57:56 AM »

My builder has me get a new case half if the bearing just falls in. The OP said there was no play top to bottom. Only side to side which seems strange. I am sure Niel will know

rsss396 · « **Reply #4 on:** September 05, 2013, 09:54:57 AM »

I would think there is a small amount of up and down movement as the cases warm up, and as time goes on will only get worse.

I think the fuel breaks down the loctite allowing them to spin again, I have hillbilly'd them before and used Green retaining loctite and put a little sealer on the face of the outer race of the bearing toward the case, then after dropping it in the case applied a little 3bond sealer again to the other side of the bearing between the race and case. This was done only to keep fuel from breaking down the loctite. It seamed to work in this case but obviously not a real fix for the problem, but sometimes customers just do not have the money to do it right so this was the cheapest fix I could come up with until new cases could be located.

bholzgen · « **Reply #5 on:** September 05, 2013, 11:06:33 AM »

I for sure will not be getting new cases. I purchased these cases from RB Racing in Michigan when I rebuilt the motor. Had them powder coated as well. I have too much money into them to just get different ones...

rsss396 · « **Reply #6 on:** September 05, 2013, 11:36:22 AM »

is the crank sliding inside the inner race of the bearing or is the outer race of the bearing slipping inside the cases? or where did you apply the loctite last time you had it apart?

bholzgen · « **Reply #7 on:** September 05, 2013, 12:11:38 PM »

Outer race of bearing is slipping inside the cases. I applied the loctite bearing retainer to the outer race of the bearing, and then installed it into the cases. It sat for a week or more and had plenty of time to cure.

rsss396 · « **Reply #8 on:** September 05, 2013, 12:24:19 PM »

OK well you could try my hillbilly technique or send them out and have them repaired with bushings

bholzgen · « **Reply #9 on:** September 05, 2013, 12:40:19 PM »

Who repairs them other than BDT?

rsss396 · « **Reply #10 on:** September 05, 2013, 01:05:09 PM »

I had saved a link to a shop that said they did case repair's, if I find it I will post it up. Other wise I would maybe see if Pete Schemberger can do it I believe he does it on the LT500's I think his number is 360-281-2274

bholzgen · « **Reply #11 on:** September 05, 2013, 01:07:18 PM »

Thanks, Any idea how much that would cost?

Also it would be interesting to see what an engine builder has to say about this.

I will have to give Pete a call.

rsss396 · « **Reply #12 on:** September 05, 2013, 01:25:22 PM »

no, i have no idea of a price

chrisr · « **Reply #13 on:** September 05, 2013, 08:05:27 PM »

Try Jerry Hall at HPR out in Arizona. He does top notch work and most everybody with quadracers sends their cases to him for new bearing inserts.

Pumashine · « **Reply #14 on:** September 05, 2013, 09:04:55 PM »

http://www.ebay.com/itm/INNER-MATCHING-CRANK-CASES-ENGINE-MOTOR-OEM-HONDA-ATC250R-250R-1985-1986-TRX-/390652975338?pt=Motorcycles_Parts_Accessories&hash=item5af4bb58ea $250 for a set of cases. Hurry before Carlos buys it.