Robbin EH29C broken rod - Do I need a full Rebuild kit?

[JPonLKN]

First place I stopped was Tractor Supply...no fine thread bolts that I could find. I did find a old timey fastener shop about 40 mins from me, took a not so quick ride on the bike up there and got what I needed. What ever happened to old mom and pop hardware stores...This place had a line out the door, and reasonable prices, $1.88 for the bolt. I will use the hydraulic method...fill the annular space with oil, then use thread tape and run the bolt down with an impact...Shouldn't mushroom against fluid...will strip threads before it does that...It will pop off. Gotta finish some real work first to pay the bills, then see what happens.

[JPonLKN]

Clutch "popped" off without a problem...now the bigger issue.
Anyone ever have a head bolt get stuck on the way out? My dewalt 20v impact won't turn it out, without a breaker bar, a 1/2 drive socket wrench isn't moving it. I can put an impact on it, but geesh....this is on the way out, not tightening it. Hat to mess up the threads in the aluminum block. Thoughts?

[cart around]

Aluminum expands twice as fast as steel does with heat. I would heat the head.

[JPonLKN]

Originally Posted by cart around

Aluminum expands twice as fast as steel does with heat. I would heat the head.

Thanks Cart...was thinking the same thing after posting, I put some WD-40 on it and put some heat to the block. Took it easy, turn both ways, a little more each time and it came out. Bolt is actually intact, not sure about the threads in the block. It was weird...came out a couple turns, then bound up. Need to get a tap in that hole to clean up the threads, but the heat definitely opened up the bolt hole enough to loosen the grip on the bolt.

[JPonLKN]

Anyone have any success polishing a crankshaft journal and having it last without destroying the rod bearing surface? One Crankshaft journal has some scoring in the direction of rotation...planning on getting some emory cloth, 400 and 600, using a shoe lace around the emory cloth and journal, using some oil, and work it till the ridges smooth out where I can't feel them with a fingernail. I'm afraid I may end up taking too much material and end up with play at the crank journal. More room for oil?

[CP241]

My thoughts, is that the more room for oil creates oil pressure issues.

[JPonLKN]

Originally Posted by CP241

My thoughts, is that the more room for oil creates oil pressure issues.

Not sure I follow where you are going with this?

I'm just talking about the tolerance between the rod and journal on the crank. I mean, this thing ran until one of the rod bolts came out completely...meaning it was loose for some time and worked it's way out of the rod entirely at which point the thing let loose and broke the rod. I put a 6" caliper on it, but wasn't getting consistent measurements...put another caliper on it from the same mfg. and got different inconsistent measurements. Ultimately, I can't tell if I am within tolerance or not now, and suspect that I won't be in tolerance after I polish the journal. I was just curious if anyone has repaired a journal like this and had long term success?

[trig123]

I think what CP was saying is if the shaft is worn it will lose oil pressure as the engine gets hot because of the space that is there because of it being worn.

These crankshafts are pretty tough. I have been able to save them. Just be careful on how much you remove with emery cloth.

See if you can clean it up the best you can and have someone check the crankshaft with micrometer. Here are you specs

[JPonLKN]

Update: Lower is back together...crank cleaned up very well. Broke a valve guide pulling a seal off. $46 for one at DIY golf Cart, and $34 @ performance plus carts....seems steep. Any better source? Also, any concerns with removal, replacement? I have the manual, says press it out. Does it matter which direction?

[JPonLKN]

Got the valve guide out and ordered a new guide...sounds like I need to re-cut the valve seat when the new guide goes in...doesn't seem like that should be necessary. Will I need to ream the new guide? Possible to just do an extensive lap job on it to get the new valve to seat? Maybe use the old valve to do the initial "cut", and the new valve to seat it? Any thoughts? Any "do it yourself" tricks to install the new guide and cut the valve seat?