AR 195 Heat Soak

[dshscarab]

Sounds probable. I took the boat out today. With the Ribbon delete, there is definitely a difference from out of the hole and acceleration. Didn't really do much for my top end. Still only getting 42 on the lie o meter. I think my phone GPS showed 42.8. That was after adjusting my throttle stop. Just about the only thing I did not do when I did my 10 hour service was open my airbox. Now you have me thinking. I also run Rec 90 ethanol-free fuel. I do think the 2019's are a little slower. I am just not so sure it should be running at 41 42. That seems really low. Especially for a 14 hour new boat.

 

[Matts18]

What were your rpms at that top speed?

 

[dshscarab]

I think right around 7200.

 

[DavisAR195]

I think right around 7200.

Yeah that’s a key sign that something is going on as you should be seeing your RPMS between 7650 - 7750 at WOT.

 

[Matts18]

Seems like it should be higher. Do you wet slip the boat? Have you tried gas from more than one station in case the gas isn’t really rec 90?

 

[dshscarab]

No to wet slip. I have tried gas from different stations but always use the ethanol-free. I do have the L 13 cone which if I remember correctly, after install. that is when my rpm's went down. When I removed all spacers, cavitation returned but the rpm's didn't. The last couple outings, I only had the blue spacer on. Had very little cavitation but only had 7150 -7230 rpm. I am going to try to switch to the gold spacer which is thinner then the blue. I also have to check my airbox in case something is in there that shouldn't be. That is the only thing I didn't check / do when I did the 10 service.

 

[DavisAR195]

No to wet slip. I have tried gas from different stations but always use the ethanol-free. I do have the L 13 cone which if I remember correctly, after install. that is when my rpm's went down. When I removed all spacers, cavitation returned but the rpm's didn't. The last couple outings, I only had the blue spacer on. Had very little cavitation but only had 7150 -7230 rpm. I am going to try to switch to the gold spacer which is thinner then the blue. I also have to check my airbox in case something is in there that shouldn't be. That is the only thing I didn't check / do when I did the 10 service.

I have the same motor and pump as the 2019 with a slightly different haul design. I'm running the lucky 13 cone with all 3 spacers installed and seeing RPM's at 7,600 and a top speed of 50.0 GPS with a full tank of gas. Have you ever seen your RPM's higher? I'm almost wondering if somehow you got a high elevation impeller installed on your boat. @SamCF or @swatski any thoughts?

 

[MNPAT]

I think a high elevation impeller would make it spin even higher rpm than what it would normally operating at low elevation.

 

[dshscarab]

Interesting theory. How could I tell? Is there a visible stamp or something on the impeller? Yesterday, It was my wife and I with 70 percent gas. No extra equipment as the cooler was empty and 7 life vest on board. Only got up to 42 mph in the intracoastal with relatively flat conditions. 88 Degrees temp. I just inspected my airbox. Everything looks good / new. I did pull the snorkel off since that seems to be the general consensus.

 

[dshscarab]

I must say other then the lack of top end, the boat does run very good. Smooth. Prior to the L 13 cone, I did have the cavitation at hole shot but probable not any more then what I was reading about on this forum.

 

[Matts18]

Are you saying that this issue only started after you installed the L13? Could something be slightly off with the pump from reassembly?

 

[dshscarab]

I'm not saying it started when I switched cones. I just really didn't notice it until switching cones. If that makes any sense. I don't think I ever ran it full throttle with the factory cone. I noticed the cavitation so I almost immediately bought the L 13 cone. Besides, it's such an easy installation with only four bolts, I don't see how any way it could possibly been messed up on reinstall.

 

[Matts18]

I doubt you messed up the reinstall, and this may have been covered in another thread, but was there sealant between the parts of the pump you took apart? Maybe some is needed?

 

[dshscarab]

There wasn't much sealant between the parts. I did apply a thin coat a sealant using black RTV. Maybe I should have put a thicker coat on but I would think the rpms would still be high. I do appreciate all your suggestions though and trying to help me with this.

 

[dshscarab]

Hey I just checked the connext trip log. Apparently the fastest the boat has seen is 45.6 MPH. Maybe the redesign hull and the L13? As previously stated, I removed the blue washer and replaced with the gold one. I will retest probably not till next Thursday unfortunately.

 

[Gym]

Doesn't the ribbon on your throttle body intake also perform as your flame arrestor? I

 

[dshscarab]

Yes it does. There is countless discussion on the removal and risk.

 

[Chris D]

Something is up as you should be seeing about 7,600 to 7,700 RPMS and about 10 more MPH. I have a 2017 AR195 with a Lucky 13 and run 50 to 51 with the top up and 4 people in the boat. What elevation are you at?

What shims are you using? Thanks

 

[DavisAR195]

What shims are you using? Thanks

I have all 3 spacers installed. I found only a 50-100 RPMs difference between 0 - 3 spacers.

 

[swatski]

I'm not saying it started when I switched cones. I just really didn't notice it until switching cones. If that makes any sense. I don't think I ever ran it full throttle with the factory cone. I noticed the cavitation so I almost immediately bought the L 13 cone. Besides, it's such an easy installation with only four bolts, I don't see how any way it could possibly been messed up on reinstall.

The base of the L13 is angled, this means the narrow side of the cone base sits on the top side of the hub. This way the tip of the cone will point into the center of the venturi nozzle after install. I would check the tip is centered - in the venturi opening.
If yours is possibly reversed (tapered or pointing "down") it could possibly influence the boats attitude pushing the bow down? - kind of like trimming an outboard down, or shimming the pump venturi down - if that makes sense.

Just thinking out loud...

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