Side car/3 wheeler carb problem

[fredvv44]

I have a Morgan replica 3 wheeler with a Cal2 engine, PHF36 carbs. When doing hard cornering I smell gas and the engine stumbles when I accelerate. It seems like the lateral forces are pushing the fuel to the side of the carbs and starving or flooding the engine; not sure which. This happens with both right and left turns.
Any ideas as to how to fix this?
Thanks,
Fred V

[John A]

Float level is probly a little high.

[sidecarnutz]

I agree to check float level. If it's still an issue, slow down some. You're no longer leaning them into corners. So the G forces are sloshing the gas to one side. Make sure the bowls are vented well and drain off under the bike away from the exhaust! I have a lot of time with Guzzi Sidecars under my belt. Very little trike experience. It wasn't an issue on my sidecar rig, so float level is a good bet IMO.

[fredvv44]

Thanks for the replies. I did lower the float level to 17.5mm which is the lowest level recommended.

Is it possible that a syphon gets started and sucks the fuel out? These 3 wheelers can corner like a formula 1 car so the lateral force is much higher than a sidecar.
Fred V

[Antietam Classic Cycle]

Perhaps rotate the top of the carbs inward slightly?

[John A]

Fred tell me more about your Morgan replica, if it corners that well ,I might have to build one!

[jacksonracingcomau]

Thanks for the replies. I did lower the float level to 17.5mm which is the lowest level recommended.

Fred V

By whom?
Actually you'll find way lower on some sheets 22.5  even but 19 works for me
Measured from join of bowl to top of float,
Could simply be needle seat not up to it
I'd fit needles & seats, if still occurring fit clear bowls, film the action, float level marked to see if it rises
Had a bit to do with Trikings once, never heard of this problem.

You can test needle seat with mity vac on pressure if you have one

[fredvv44]

Fred tell me more about your Morgan replica, if it corners that well ,I might have to build one!

It is a JZR brand kit from England. Google "JZR 3 wheel". I also did a blog of my whole build; see:
jzrusa2.blogspot.co m

Really great fun to drive. I've had it up to 85 mph on the interstate but I like curvy back roads the best.
Fred V

[oldbike54]

Perhaps rotate the top of the carbs inward slightly?

 Thinking ... thinking ... hmm , won't that just cause the "inside" carb to overflow ?

  Dusty

[fredvv44]

By whom?
Actually you'll find way lower on some sheets 22.5  even but 19 works for me
Measured from join of bowl to top of float,
Could simply be needle seat not up to it
I'd fit needles & seats, if still occurring fit clear bowls, film the action, float level marked to see if it rises
Had a bit to do with Trikings once, never heard of this problem.

You can test needle seat with mity vac on pressure if you have one

It was in the Delorto manual. Here is a link to a PDF of the page. I used fig. 13 for the 2 float carb.
http://www.dellortoshop.com/drawings/dellorto_float_level_instructions.pdf
I also read that with a fuel pump I should use a smaller diameter needle.
I like the clear bowl idea. That would tell me exactly what is happening. Where can I get those?

BTW, this happens coming out of the curve when I get back on the throttle so I imagine the damage is already done in the curve. The pump catches up and away I go again.
Fred

[fredvv44]

Thinking ... thinking ... hmm , won't that just cause the "inside" carb to overflow ?

  Dusty

I'm not sure about that either but I'll think on it some.
Fred

[Antietam Classic Cycle]

Thinking ... thinking ... hmm , won't that just cause the "inside" carb to overflow ?

  Dusty

 "Inside" carb? All I'm suggesting is rotating the carbs inward from vertical by a few degrees. Looking from the rear - instead of the carb bodies being perfectly vertical I  I , tilt them a bit /  \ . Costs nothing to try, easily reversible if it doesn't work.

One source for Malossi clear float bowls:
https://store.bevelheaven.com/Carb-Fuel-Related-etc/Float-Bowl-Malossi-Clear-Kit-PHF/M/

[oldbike54]

"Inside" carb? All I'm suggesting is rotating the carbs inward from vertical by a few degrees. Looking from the rear - instead of the carb bodies being perfectly vertical I  I , tilt them a bit /  \ . Costs nothing to try, easily reversible if it doesn't work.

One source for Malossi clear float bowls:
https://store.bevelheaven.com/Carb-Fuel-Related-etc/Float-Bowl-Malossi-Clear-Kit-PHF/M/

 The "inside" carb being the one on the inside of the corner . Seems the forces would push the fuel away from the short radius on the inside of the arc , and if the carb is tilted in the fuel would overflow on the side tilted down . Just a theory . Yes , I always tilted my beemer carbs slightly inward , different set of conditions than a vehicle that corners flat .

  Dusty

[fredvv44]

The "inside" carb being the one on the inside of the corner . Seems the forces would push the fuel away from the short radius on the inside of the arc , and if the carb is tilted in the fuel would overflow on the side tilted down . Just a theory . Yes , I always tilted my beemer carbs slightly inward , different set of conditions than a vehicle that corners flat .

  Dusty

It doesn't really corner flat. Being a 3 wheeler there is some body roll which would increase the flow of fuel up the side of the inside carb and out the vent. The outside carb would benefit from the tilting. Hey, how about linkage that would tilt both carbs to toward the inside of the curve!! LOL.

I broke the clutch cable and am waiting for a new one. I'll do a bunch of testing of ideas next week and report back.
Thanks again guys,
Fred
Fred

[oldbike54]

 So the f1 car reference was a bit of an exaggeration ? Still , corners flatter than a motorbike , at least I hope so 

  Dusty

[fredvv44]

I think I have it fixed.  The vent tubes (clear vinyl) had very soft bell mouthed bottom ends which indicate fuel present. Liquid going down a tube will hang on the bottom of the tube thus the condition I found.

I routed the vent tubes into little catch bottles and lowered the pump pressure to 3#. Driving it showed no problems in corners nor at speed on the interstate. YEA! I didn't see any fuel in the bottles and removed them and fixed the tubes to loop up higher above the carbs. I'll try lowering the pressure more too.

I think it might have been a pump pressure problem and vibration of the engine causing the float needles to not seat along with syphoning in the fast corners.

Thanks for all the input guys.
Fred V