Author Topic: blowing oil out a lot (Read 18280 times)

ariensracer · « **on:** July 20, 2006, 02:42:50 pm »

Hi well i had my first race last weekend and I went out for hot laps everything ok then went out for the first heat and i made it around three times and then the motor started to sieze up i pulled off and looked into my catch can and it was half full with oil ( I used a 20 oz bottle) So I put more oil in and tied on of my oil lines off ( I am assuming everyone else has two oil ports) and went out for the second heat and I blew the crank seal out! :shock: I am not sure what i need to do to my motor to keep if from blowing so much oil out. I have just put the motor together and followed everything to a T Also I have been told that maybe i need to run the mowtor a little longer at low rpm to get the new rings seated in before turing 5500 or 6000 anyways just curious on what anyone had to offer for ideas thanks!

So i took the motor apart the other day and it turns out my oil blowing had melted the rod to the crank a touch :shock: i had to get a new rod and burn off the aluminum on the crank so i need to get this problem fixed!

Oh I forgot to say that we were racing on a go kart track and after I blew my oil seal and pretty much turned the track into slick mode the flag guy came up to me and said "Twenty years I have been racing at this track, never seen oil like that on the track before "

I was a little

pushing my mower back to the pits but i think i gave everyone a good laugh

Thanks for the help with my mowchine!

kyle

matt25001149 · « **Reply #1 on:** July 20, 2006, 03:30:03 pm »

id say u blew out the crank seal cause u shut the line to the catch can off forcing the crankase to have enormous pressure and thus blew out ur crank seal

ariensracer · « **Reply #2 on:** July 20, 2006, 03:49:27 pm »

alright I thought that is probably why I blew the crank seal out cause I pinched the lines off but my question is why is it initially blowing so much oil out in the first place I was wondering if anyone else has had this problem. I am not sure if i need a different catch can or what to do to stop too much oil coming out :?

Thanks for the info though

kyle

hoserrb · « **Reply #3 on:** July 20, 2006, 03:56:49 pm »

blowing oil out the crankcase is because there is too much pressure getting to the crankcase. it comes by going past the rings or sometimes from worn/bad valve guides.
in the case of the rings, as the piston goes up on compression, the pressure goes into the case past the rings, then as the piston comes down, out it goes thru the breather and into the catch can with some oil.
if it's a valve guide issue, when the piston goes up pushing out exhaust, (ex valve open)some pressure goes through the guide and back into the case. then when piston comes down, pushes it out the breather.

even unseated rings probably won't blow that much oil.
check for a broken ring, egg shaped bore (common in older engines), large ring gap, or valve guide has come out or is worn bad.

matt25001149 · « **Reply #4 on:** July 20, 2006, 04:12:57 pm »

too much oil maybe??

wut u got for the the lil crankcase breather maybe try this

thx to squidd for pics well off of samis machine so thx to her too

see here for explination

ariensracer · « **Reply #5 on:** July 20, 2006, 04:20:05 pm »

That picture is exactly what i have on my motor thanks for the help guys i apprecite it! I will pull my piston out tonight and check ring gap and stuff i know my bore is round cause i honed the baby out before putting everything together i just wonder if i need to break it in a little longer before turning a lot of rpm not sure what is going on? What do you guys use for a catch can? Maybe my 20 oz bottle is the wrong thing to use :?

Thanks again for the help

Kyle

cycloneracer · « **Reply #6 on:** July 20, 2006, 04:21:57 pm »

Kyle,
That sure made turn 3 REAL INTERESTING!!!!
I didn't get a chance to look at your mower. But yea, the tying off of the breather lines made the seal blow out. As for the puking oil. I assume you are not running a breather and have 2 ports like in the pic posted. Did you drill the drain back hole in the valve spring area? If no, that is your problem. The oil can't drain back fast enough from the valves through the stock tiny hole. I think I drilled mine out to 3/16.
On that rod make sure your not over tighting it. That may be why it siezed.
Hope this helps

Paul
#150 SP
Easy Parcheesy Racing

hoserrb · « **Reply #7 on:** July 20, 2006, 05:47:27 pm »

i think it siezed because most of the oil left the motor and made it to the catch can.
your catch can type and size had nothing to do with blowing 10 oz of oil in 3 laps
a good working engine should lose very little oil at high rpm even without the hole drilled out.
the obvious things are rings and guides. look there first.

ariensracer · « **Reply #8 on:** July 20, 2006, 05:50:36 pm »

Paul, thanks for the info and yes i did drill out the drain hole 3/16 and i do not have a breather i think i will make one any ideas what to use to make a breather? I just used a 20 oz bottle before and i taped the hoses inside the bottle i saw some others that had filters on top of them just curious if you have any pics or what on how to build these thank you for the help hopefully i can make it to the austin race!!

Thanks again

Kyle

Squidd · « **Reply #9 on:** July 20, 2006, 07:13:30 pm »

How much did you hone it out to make it round...??

Check ring end gap....(bare ring in cylinder)...and taper ...(check couple spots...)

ariensracer · « **Reply #10 on:** July 20, 2006, 09:12:33 pm »

I honed out the cylender enough till i felt no more pressure against the hone as in i took the taper out of the cylender. I initially had ten thousands piston to wall but I could not find .10 over rings so i went with .20 over rings and filed the ends to match well and i did it at the top middle and as far as I could go to the bottom it looks good to me. I have torn the piston and rings out everything looks good as far as I can tell not sure what the problem is but I will try again I guess. :?

thanks for all the help everyone

Kyle

kart88 · « **Reply #11 on:** July 20, 2006, 09:32:25 pm »

If a cylinder is already out of round honing alone will NOT make it straight unless you have a LOT of time on your hands and by the time you were through you'd be only a few thousandths away from being the next size over IF you weren't already there. The only true way to fix an out of round bore is to have it align bored to the next size over. I'm not famialar with the rules you guys run under so i don't know the rules on how far you guys can bore or if you're even allowed to.

Red Horse Racing · « **Reply #12 on:** July 20, 2006, 10:40:50 pm »

That's what I was thinking too, you can hone all day, but it'll take pretty much the same off all the way around the cylinder. Boring is needed to round things correctly.

What I did notice was you just taped the hoses into the catch can? How is it vented to the atmosphere? If it's not open to atmosphere through that filter you've seen on others, you don't have a breather, you've just slightly increased the capacity of closed crankcase. Therefore, pressure has no where to escape, therefore, blowby.

Dale

mowdak1 · « **Reply #13 on:** July 20, 2006, 10:47:25 pm »

Quote from: "ariensracer"

... I just used a 20 oz bottle before and i taped the hoses inside the bottle i saw some others that had filters on top of them just curious if you have any pics or what on how to build these thank you for the help hopefully i can make it to the austin race!!

Thanks again

Kyle

If you go back to the thread Matt linked above Kyle, there is a picture of one built out of PVC... Total cost of that one will run about $8 - $9. All you need is a short length of 2" PVC Pipe 4 - 6 inches in length, 2 PVC caps, then you'll need 2 fittings for your oil lines, one fitting with valve for your drain line. The breather can be/is a standard off the shelf Walmart chrome plated valve cover breather... Cost maybe $3.

Drill one of the PVC Caps, before you glue it on the pipe preferably, it's a little easier to manage that way and you don't have to try and clean all the plastic out of your catch can afterwards, then use the die grinder, moto-tool, hand drill or drill press with a small sanding drum to hog it out to fit the tube on the bottom of the breather. Just remember you need room for your grommet, and it needs a little room to expand to get the breather in there.

The fittings for the oil lines are simply drilled and tapped to fit whatever size fitting you choose.

Fast Eddie and I whipped out a half dozen of them in the G-Team shop this spring in less than an hour total, for stock on the trip to the Minnesota Build Clinic. That's from scratch... sack of parts and a piece of pipe. Less than 10 minutes each.

matt25001149 · « **Reply #14 on:** July 20, 2006, 10:54:24 pm »

now will putting a t in the line that goes from the motor to catch can to operate a fuel pipe or not ??

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Author Topic: blowing oil out a lot (Read 18280 times)