Forward cylinder oil line continually gets air bubbles - 97 XP - 787 - Any ideas?

[s14unimog]

So I've often wondered what originally killed the forward piston on the previous engine (with the previous owner). As I've observed this recent rebuild, I've noticed that my forward cylinder oil line keeps going empty or keeps getting air in it form some where; this might have been the culprit. I've only got about 8-10 hrs on this new engine and I was too afraid to leave the premix on my second tank; which is starting to look like a good call. I had been watching it over the weekend, since the lines are new a very clear, and it seems to keep getting air in there from somewhere.

If I get down there and hold the oil valve wide open I can fill the line and remove most of the air bubbles (seems to help if I pinch the oil line momentarily and release). As the day goes on, the air somehow gets back in there and sure enough that oil line will all but empty out. Is this a common symptom that any one has encountered. I have the lines secured over their barbs with two zip-ties on each end; maybe air is getting in at the connection? The rear cylinder line stays full with no bubbles. Any help or lent experience would be appreciated.

1997 Seadoo XP - 787 Rotax (now 796cc)

Thanks in advance for the help!

-Brandon

 

[Dr Honda]

Is your pump passing air, or does air show up after a run? (or do we know for sure?)

Check the bolts on the top cover, and make sure the bleed screw on the front of the pump is snug. DO NOT over tighten the screws. They are small, and can break easy.

On the 800 engine, the check valves are in the manifold. You may want to make sure they are clear and working.


Your Avatar looks familiar. Do you hang out on the RZR forum?

 

[s14unimog]

Is your pump passing air, or does air show up after a run? (or do we know for sure?) Check the bolts on the top cover, and make sure the bleed screw on the front of the pump is snug. DO NOT over tighten the screws. They are small, and can break easy. On the 800 engine, the check valves are in the manifold. You may want to make sure they are clear and working.

Your Avatar looks familiar. Do you hang out on the RZR forum?

I think the pump is passing air. I've noticed tiny little bubbles coming from the pump side barb as I attempt to prime the lines. As I said, it seems to help if I momentarily pinch the line, as to build some pressure, and release. Otherwise, its very difficult to get a solid oil supply from the pump on that line alone. However, with that technique, I have been able to get a solid oil supply, but it seems as time passes, air gets back in there; again, seemingly from the pump side. I was diligent when bleeding the supply line to the pump (made quite a mess) to get all of the air out. I was also very cautious not to over tighten that bleed screw and I'm confident it is not stripped.

Not sure where you've seen my avatar but no I do not own an RZR nor do I frequent that forum. That's my built 240sx that I drift. I usually stay around zilvia.net for my car talk.

 

[Robj]

I had the same problem and changed the oil lines and check valve and that fixed it.

 

[LouDoo]

A couple of other things that you might want to check. When you replaced the injection lines did you use 1/8", I find that while 1/8" will work 3/32" is a much snugger fit. Also did you use small cable ties for clamps.

Lou

 

[s14unimog]

A couple of other things that you might want to check. When you replaced the injection lines did you use 1/8", I find that while 1/8" will work 3/32" is a much snugger fit. Also did you use small cable ties for clamps.

Lou

Yes, when I replaced the lines I used 1/8" ID and I also used cable ties for clamps. You think the bubbles are sneaking in at the barb connection? Have you seen that before or something?

 

[LouDoo]

I don't know, I'm just saying its a possibility, when I did mine I took the pump with me to the hardware store and the 3/32" was a snugger fit, than the 1/8".

Lou

 

[s14unimog]

I don't know, I'm just saying its a possibility, when I did mine I took the pump with me to the hardware store and the 3/32" was a snugger fit, than the 1/8".

Lou

Right on. I was thinking that the cable tie might tighten around 95% the hose but actually scrunch up a small area under the buckle and create a path for air to get in. Although I have two on each end, I have them inline with each other. I'm going to order some Oetiker single pinch ear types and really get it on there. I want to say I could almost see it happening but I was on the lake and it was difficult to really focus on it. Where else could the air come from!?

Robj:

Where is this check valve you speak of?

 

[s14unimog]

Ya know the more I look at the connection at the pump, the more I think it's letting in air at the barb. I've noticed the tiniest bit of oil leaking there so surely the lines aren't tight enough. In hindsight I think a 3/32" line is probably a better fit than the 1/8" and something better than a ziptie is needed.

 

[Thumper3322]

Get the OEM oil line clamps... Air can sneak in there, but if you have 2 on there it shouldn't get completely empty.