My 2009 assault just went down for the third time, but this time the connecting rod bearing seized up. When I was tearing it down I noticed an air pocket in the oil line just after the filter so I took off the line and filter and no oil would drip out. Then I opened the cap and it poured out. This doesn't seem rite to me. Is this normal or is my cap vent not working
oil cap?
- Thread starter mormud
- Start date
I have read posts reading poorly venting caps. Based on what you experienced I would get a new cap for sure.
some people have drilled a small hole in their cap to prevent this from happening. you will have to deal with oil leaking when you roll it.
it seems like the cap only works as a vent in a short window of angle, downhill being less likely to work. maybe you could take your cap off and test it to see if it is even working at all?
it seems like the cap only works as a vent in a short window of angle, downhill being less likely to work. maybe you could take your cap off and test it to see if it is even working at all?
R
rmk addict
New member
Ive taken mine off and tried blowing through it each way. Couldn't really get any air to go through there.
Anyone have a line on where to get a decent oil cap or something comparable?
Anyone have a line on where to get a decent oil cap or something comparable?
i drilled a small 1/16 hole on the inside of the cap on both of my sleds. my 08 dragon had air bubbles every ride and now i havnt had one since. i do get a little oil residue on the top of the cap ocassionally but really a non issue. my oil consumtion went up too.
so this is fairly common but could it be the cause for engine failure? i am about to put a different motor in it and want to try and fix what went wrong
no oil is a very bad thing for an engine. temps go up and you can seize your engine.
I'd say that as soon as you loosened the oil cap, you had your answer. No oil is gonna be a direct cause of a rod bearing failure.
You don't think the oil pump will pull the oil when motor is running
No. It's a gravity fed type of system. Otherwise priming the oil pump wouldn't ever be necessay and air bubbles in lines would never occur.
I started a thread about this a couple of years ago. I found the same thing as the O.P of this thread. After finding an air bubble in my main feed line for a 2nd time in less than 150 miles, I decided to spend some time tinkering. To my astonishment, when I removed the Main Oil feed line from the oil pump to insert a bolt so oil didn't leak, no oil would come out. WTF???
At first I thought the little filter might have been plugged however, when I unscrewed the oil cap, out came full flow of oil.
What I also found was air bubble's in 2 of the oil lines going to the mag side. Is it a coincidence that I found the mag cylinder skirt cracked and delaminated nicasil at 600 miles ??
Since then, I have found and tested (11 out of 12) 2007-2010 IQ's that have closed cap vents as the sled sits on level ground. The problem with this is the cap vent is closed at level attitudes because the cap sits at approximately 30 degrees.
Many disagreed with me at the time feeling the cap only needed to vent occasionaly. OK but what about trail rider's and flat landers? Some of our best riding areas around here require a 10-15 mile trail ride in.
The easiest thing to do is to drill a tiny hole wherever you prefer and deal with a little mess on rollovers. I have been testing some different cap vents that I have fab'd from some transmission cases that were being scrapped. When i get what I feel to be the perfect vent, I'll let you guys know.
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here is the question i have...okay i have changed oil filters on 2 of these sleds recently. when i pulled the oil line loose oil was flowing just fine which tells me that the oil caps were working properly.
My question is are certain caps defective or do they all start out working fine and then random ones end up failing and not venting? Right now my sled is so clean that you could eat off of it, but if drilling a tiny hole in the oil cap will ensure dependability, then i guess i can deal with a little mess... or since i know my cap is working properly, do i just have a good cap and dont need to worry about it?
Could someone post a picture of where they drilled the hole. I don't want to drill in the wrong place!
Thanks,
Idaho Bill
Thanks,
Idaho Bill
trying to post a pic from my phone but this new iphone is kicking my butt
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I had same problem on 08 700, Mag side went down twice found that oil tank would hold 10" vac. replaced all seals and water pump and oil pump shaft seal and oil tank cap. Drilled and tapped oil tank with fitting from 96 ultra and ran the lines up on the handle bars for a vent. seems to work no piston problem yet but days still early to.
