Mating the engine case together

[45 lt80]

I having a hard time getting the cases together. I've try for only 15 mins. before had get tried for work. I can get if down to about one inch. Its hanging up in the trans. gears part of cases. Is where a secret to putting the cases together. I don't remember it being so hard in the past. :mad: :mad: :mad:



Thank you
45lt80

[hang1p]

i had a problem like that once my shifting fork was not in right pushing my gear shaft over slightly so it would not come together

[Rich250RRacer]

Originally posted by 45 lt80
I having a hard time getting the cases together. I've try for only 15 mins. before had get tried for work. I can get if down to about one inch. Its hanging up in the trans. gears part of cases. Is where a secret to putting the cases together. I don't remember it being so hard in the past. :mad: :mad: :mad:



Thank you
45lt80

What have you replaced here? The left bearing is a press fit on the crank, which can be done be heating the bearing and freezing the crank. I prefer to do it as the Honda manual states, with the special tool from Honda. The tool is kinda expensive, but I do enough motors, so it's paid for itself many times over. The only way the cases will go together by hand is if you have a worn left hand crank journal.

[45 lt80]

Rich250rracer

The cases was leaking real bad at bottom. The motor has ran with the new bearing in place. I took it apart to see if the cases was cracked or see if the mating surface had something wrong with it.

45lt80

[beerock]

Originally posted by Rich250RRacer
What have you replaced here? The left bearing is a press fit on the crank, which can be done be heating the bearing and freezing the crank. I prefer to do it as the Honda manual states, with the special tool from Honda. The tool is kinda expensive, but I do enough motors, so it's paid for itself many times over. The only way the cases will go together by hand is if you have a worn left hand crank journal.

im not following you completely here rich? the right hand case will go into place with no forcing? so thereofr the cases can be put together for final assembly without being pressed?

unlee your talking about JUST the left case?

[atvmxr]

i definately had to freeze my crank and heat both case halves to get the whole assembly together. Wasnt too big a deal, just put the left side case in the oven at 200 for about and hour. Thats what is sounds like to me if you are coming up an inch short.

[Rich250RRacer]

Originally posted by beerock
im not following you completely here rich? the right hand case will go into place with no forcing? so thereofr the cases can be put together for final assembly without being pressed?

unlee your talking about JUST the left case?

Yeah, the crank has to be pulled into the left bearing (when everything is at spec). I have had one or two where the right side was a little tight (brand new cases, bearings, crank) and I've had to use the tool on that side too, not as tight as the left side but just tight enough. The cranks must not have as good a finish as we think.

[krazykarl]

i've donr my bottom end like 4 or five times, and i've definetly got hung up on the output shaft, its just ral important to go down on it perfectly straight. i've never had problems with the crank bearin. its a tight fit but it goes on and off, alsomake sure your shifter shaft is out, i've seen lazy guys who didn't want to take apart there clutc htryin to put the cases back together with it in. didn't workout so well. espesily if your shaft is a little bent, from a popped chain. well thats my 2 cents. good luck

[Rich250RRacer]

Originally posted by krazykarl
i've donr my bottom end like 4 or five times, and i've definetly got hung up on the output shaft, its just ral important to go down on it perfectly straight. i've never had problems with the crank bearin. its a tight fit but it goes on and off, alsomake sure your shifter shaft is out, i've seen lazy guys who didn't want to take apart there clutc htryin to put the cases back together with it in. didn't workout so well. espesily if your shaft is a little bent, from a popped chain. well thats my 2 cents. good luck

You must be refering to the right side because the only way a crank will go in the left side without heating or the tool is with a worn crank journal.

[250r4life]

well i just redid my bottom end... i bought a brand new OEM crank assembly, and new main bearings and seals and etc...

i heated up the cases to get the main bearings out, and froze the new ones to get them back in, but i didnt have any problem getting the cases back together over the new crank assembly... it took some tapping and what not, and was a tight fit, but...

where exactly are you guys saying there should be a "hang up?"

[Rich250RRacer]

Originally posted by 250r4life
well i just redid my bottom end... i bought a brand new OEM crank assembly, and new main bearings and seals and etc...

i heated up the cases to get the main bearings out, and froze the new ones to get them back in, but i didnt have any problem getting the cases back together over the new crank assembly... it took some tapping and what not, and was a tight fit, but...

where exactly are you guys saying there should be a "hang up?"

When installing the crank in the left half. This is a press fit into the bearing. You should NEVER tap or try to drive the crank in, unless you prefer a crank that's not true. In most cases theright side will slide right on, but like I said before, I've run into a few that haven't. Honda actually recommends using the tool on the right side also.

[250r4life]

i didnt tap the crank in... if i recall it slid... when i had the two case halves, if i recalli had to tap them the last half inch or so together...

it was a brand new crank assembly and brand new bearings, so what is there that could have been wrong that it slid together?

[Rich250RRacer]

Originally posted by Rich250RRacer
When installing the crank in the left half. This is a press fit into the bearing. You should NEVER tap or try to drive the crank in, unless you prefer a crank that's not true. In most cases theright side will slide right on, but like I said before, I've run into a few that haven't. Honda actually recommends using the tool on the right side also.

How did you get the crank in the LEFT case and bearing? IT WILL NOT JUST SLIDE IN (UNLESS THE CRANK IS WORN OUT), I've been saying this in four posts. Installing the crank in the left side should be the first step when reassembling a bottom end. As I've said before, the right side will usually slide on and over the crank.

[zedicus00]

rubber mallet, and if yur carefull you can get it almost all the way in the left and as you bolt the halves together itls suck in the rest of the way.... just b VERY carfull titening the bolts so the case goes on straight and doesnt bind a bearing up. i heated the bearing a bit before sticking the case on too... dont melt the seals or anything.

[beerock]

Originally posted by zedicus00
rubber mallet, and if yur carefull you can get it almost all the way in the left and as you bolt the halves together itls suck in the rest of the way.... just b VERY carfull titening the bolts so the case goes on straight and doesnt bind a bearing up. i heated the bearing a bit before sticking the case on too... dont melt the seals or anything.

NOOOOOOOOOOOOOOOOOOOOOOOO

you should not hit the crank into the left side case with anything!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[250r4life]

well, sure enough i got in there adn figured i understood it and didnt need to read every little thing... i apped it back in...

so... whata you think? is my crank gunna be messed up, and what are my options? its a brand new OEM Crank assembly...

[Rich250RRacer]

Originally posted by 250r4life
well, sure enough i got in there adn figured i understood it and didnt need to read every little thing... i apped it back in...

so... whata you think? is my crank gunna be messed up, and what are my options? its a brand new OEM Crank assembly...

If you're lucky, you didn't knock it out of true. The only way to tell would be to take it apart again.

[250r4life]

what exaclty would be knocked out of true... is it untrue if the bearing isnt on all the way because its supposed to be pressed on, or does the actual rod get untrue... or...? what exactly would i look for... my top end isnt on yet, so it'd be easy to check out..

[beerock]

well, just to correct my anal post.....

you can tap the crank into the left case but the crank halves are only together because of the offset crank pin, so in essence when you hit the crank your actually bending the crank halves into each other. this is being extreme. as it does not hurt it to much and i know alot of people(even myself that put the crank in this way. but the best way to put the crank in without hurting it(untrueing it) is by pulling it in from the stator outer part of the case like rich said...

[Aceman]

Don't worry about being a little anal Bee, I'd rather learn the correct way than the "just git-r-done way." I like to do it right the first time.

[250r4life]

Originally posted by Aceman
Don't worry about being a little anal Bee, I'd rather learn the correct way than the "just git-r-done way." I like to do it right the first time.

yah... im with him... i learned a long time ago not to go cheap and take the shortcuts or anything, cuz it just costs you more money in the long run... obviously i was gentle wiht it and i dont just go banging on things...

but yah, i am anal about my bike...

so anything in particular i should inspect?

[45 lt80]

I just want to say thank you for helping me out. I have learned what is wrong. I have one more question. How long does it take for the Anerobic gasket maker to set up? I'm will apply a small amount on both sides of gasket on the bottom of the engine. To help seal the engine.

Like I said before Thank you!!!!

45lt80

[beerock]

dude dont ya know your suppose to tell us what was wrong??? lol tel tel tell!!!

[45 lt80]

Dude The problem was oil was leaking from the between the cases. So I'm trying to replace the gasket between cases. That is my problem....:devil: :devil:

[atvmxr]

just find an aluminum welder and have him weld the halves together. that should stop the leak

[45 lt80]

I did think of that!!!!!!!:D :D :D