Oil drained into crank on 99 summit 670

Redneckhotrod · Dec 15, 2011

Oil has drained into crack over summer.
Who else has had this problem?
Thinking check valves in the banjo fittings.
Any other ideas?

Sent from my ADR6300 using Tapatalk

highmark00700 · Dec 16, 2011

Are you still running the oil injection? I have heard that when the oil pump gets good and worn it will leak into the crankcase while sitting.

Redneckhotrod · Dec 16, 2011

We are tuning it up for the season.
It did it last year too, once we cleaned it up, and replaced the banjo fittings(with used ones) was never really a problem. But we rode all the time last year, never really got a chance to sit too long.
Is it the banjo fittings/check valves, or can oil get into the crankcase through the pump?

highmark00700 · Dec 16, 2011

From what my dealer told me it's in the pump itself. I think its leaking past the seals. He told me the way to check it was to start the sled and clean it out, then top off the oil injection bottle. Put a marker line on the bottle where you filled it to then let it sit for a week or two and see if the level goes down in the bottle. I would imagine if you ride a lot it wouldn't have time to fill the case much.

Devilmanak · Dec 16, 2011

Unless I am remembering wrong, the pump and rotary valve shaft is in an oil filled cavity that is sealed on both sides with crank seals. Probably leaking past the seals into the lower end. If it runs fine I personally wouldn't worry about it.

Redneckhotrod · Dec 16, 2011

Also, we took his carburetors apart and found 2 different jets.
340 & 350
What are stock jet sizes for this sled?

Sent from my ADR6300 using Tapatalk

bullelkklr · Dec 18, 2011

jets and oil

the mag side runs hotter than the PTO side. The jets should be different.

I thought that the crank on these were filled??? There is a line from the oil tank directly to the crank case and a return line also....

Any one know if this should be wet/full of oil?

Redneckhotrod · Dec 18, 2011

It is a 2-stroke ... should not be full of oil!!

Line runs from oil tank to oil pump.

Sent from my ADR6300 using Tapatalk

bullelkklr · Dec 19, 2011

yep

I looked at a 1996 670 case that I had apart. Only the pump is encased in oil - the rest of the crank is sealed off from the pump via the crank seals.

vinpie1 · Oct 14, 2012

I have seen this many times. There is an inner and outer oil pump seal on the rotory shaft/oil pump shaft. If the outer seal goes, the sled leaks oil all over the place (soaked my trailer deck). If the inner seal goes out, the crankcase fiills with oil. It makes it hard to start for the first time of the year, but I know 2 that have gone for years this way. Its automatic summerization! The outer seal can be changed easily with the motor in, but the inner will require the cases to be split.

sledsrock · Oct 14, 2012

Redneckhotrod said:
It is a 2-stroke ... should not be full of oil!!

Line runs from oil tank to oil pump.

Sent from my ADR6300 using Tapatalk

You also have 2 big lines running to the inner cavity behind the oil pump, this cavity is full of oil at all times (or at least should be). If the inner crank seals are leaking it will allow this oil to seep into the crankcase (rod/piston area). The oil level will drop in the reservoir when this happens. If this is the case it will require the cases to be split and the crank seperated to replace these seals.

Search

Oil drained into crank on 99 summit 670

Redneckhotrod

New member

highmark00700

Free Member

Redneckhotrod

New member

highmark00700

Free Member

Devilmanak

Well-known member

Redneckhotrod

New member

bullelkklr

Free Member

Redneckhotrod

New member

bullelkklr

Free Member

vinpie1

Member

sledsrock

Well-known member

Similar threads