Last ride out the base gasket went south, so while I have it apart I found enough rod clearance(0.045 almost,limit is 0.028) to make me want the bottom end done as well.There is no up and down movement of the crank,rod and piston,but there is enough every where else that I'm glad I caught it before something ugly happened.
These two pics show the generous amount of rod clearance.
The piston itself looks pretty decent for what I've put it through.At least it's not cracked.It's an 89mm Vertex.Considering what I see on the bottom end I'm surprised it's not on it's last top end.
I'm thinking that if I find a new crank assembly and get my trusted auto teacher to bore the cylinder that I can do the majority of the work myself.I read some where that you have to go with an 85 crank assembly.No problem.Who has them available?
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"If the rule you followed led you to this of what use was the rule?" Anton Chigurh
What you don't see is the right side of the connecting has been hitting the crank. Am I being to cautious? I don't mind spending money now to rebuild it
To me it's an antique and I'm all about preservation.
I did give the engine a bath in the parts cleaner at work.The only sludge was around the bottom where the base gasket had leaked.
Fins Rule!
Liquids drool.
"If the rule you followed led you to this of what use was the rule?" Anton Chigurh
things look alittle "dry" if you ask me. what oil and ratio was you using ? also the color of the plug looks lighter than i would like to see in mine. im just thinking out loud so feel free to disregard my observation
arleybeer40 wrote:Sorry it did'nt look so bad in the pics. i would rebuild from the bottom up. Did you check the clearences first though? Always looks worse than it is
Thats no prob.The rod side clearance is almost 0.045.Since there was no sign of blow by and no up and down movement of the piston and crank assembly I may just run it.The crank I can replace this winter since I wouldn't bother with the original anyways.
Fins Rule!
Liquids drool.
"If the rule you followed led you to this of what use was the rule?" Anton Chigurh
100hp honda wrote:things look alittle "dry" if you ask me. what oil and ratio was you using ? also the color of the plug looks lighter than i would like to see in mine. im just thinking out loud so feel free to disregard my observation
Shes just dry from the parts cleaner I used at work. To be honest it wasn't all that bad except where the gasket leaked. That is why the plug looks kind of light because she was sucking air. As for oil ratio I stick with 28:1 and use Esso brand semi synthetic.
Fins Rule!
Liquids drool.
"If the rule you followed led you to this of what use was the rule?" Anton Chigurh
Two things:
If the base gasket pushed out the cylinder base is probably warped. Have it checked before assembly. If the base bolts get overtightened the corners will pull down in the area around the base bolt holes causing the warpage. I just put one together that had that problem. The motor came from a 91 500 donor, was rebuilt crank and all and went in a gen III AF.
The thrust washers and bearing can be replaced if you have a good crank guy around. Wiseco has the washers and bearing. The crank has a sheet metal windage casing that the crank rebuilder must protect during disassembly and re-assembly. You save around $100. if the rod is saved VS a new rod. Superior sleeve does the job. Their #503 786 9356
its the thrust washers that wear out and give you the side play.
You could probably get it back in spec just by replacing them, although I guess a new bearing wouldn't hurt.
side play doesn't matter, its axial play that shows signs of wear. you should feel very little axial play, if you can push the rod so you are at BDC and you can touch the crank weights with the rod, its toast.
'09 kx450f 4-Poke
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Thank you All for the helpful replies. I am new to these engines, so getting advice from those who Know and are Willing too Share makes life much nicer.
Considering that there is no up and down movement in my engine I'm going to slap it back together with a quick hone and new rings. I seen a pic some where showing a connecting rod that looked like a popsicle stick it was so thin and yet the piston hadn't hit the head so I feel some what safe.
This winter though I will do a proper rebuild. Right now I just want to hit the trail!
Thanx again for the replies Gents !
Fins Rule!
Liquids drool.
"If the rule you followed led you to this of what use was the rule?" Anton Chigurh
CRMOE500 wrote:What you don't see is the right side of the connecting has been hitting the crank
did everybody overlook this detail . a new crank now will give you another 10years of use
You are right. A new crank would be nice, but for the rest of this season and what riding time is available to me I think it should be ok. Like I said earlier I've seen worse and still ran with out smashing itself. I don't plan on going like a mad man anyways.
BTW the original trans shifts great and seems to never have been touched. Neutral can be a little tricky to find at times but thats it.
Fins Rule!
Liquids drool.
"If the rule you followed led you to this of what use was the rule?" Anton Chigurh
[quote="mega491"]Two things:
If the base gasket pushed out the cylinder base is probably warped. Have it checked before assembly. If the base bolts get overtightened the corners will pull down in the area around the base bolt holes causing the warpage.
Checked it like you said and the base is flat. By next weekend I should have her going.
Fins Rule!
Liquids drool.
"If the rule you followed led you to this of what use was the rule?" Anton Chigurh
!
. a new crank now will give you another 10years of use